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1.  Infectious diseases in healthcare workers – an analysis of the standardised data set of a German compensation board 
Healthcare workers (HCW) are exposed to infectious agents. Disease surveillance is therefore needed in order to foster prevention.
The data of the compensation board that covers HCWs of non-governmental healthcare providers in Germany was analysed for a five-year period. For hepatitis B virus (HBV) and hepatitis C virus (HCV) infections, the period analysed was extended to the last 15 years. The annual rate of occupational infectious diseases (OIDs) per 100,000 employees was calculated. For needlestick injuries (NSI) a rate per 1,000 employees was calculated.
Within the five years from 2005 to 2009 a total of 384 HCV infections were recognised as OIDs (1.5/100,000 employees). Active TB was the second most frequent cause of an OID. While the numbers of HBV and HCV infections decreased, the numbers for active TB did not follow a clear pattern. Needlestick injuries (NSIs) were reported especially often at hospitals (29.9/1,000 versus 7.4/1,000 employees for all other HCWs).
Although they are declining, HCV infections remain frequent in HCWs, as do NSIs. Whether the reinforcement of the recommendations for the use of safety devices in Germany will prevent NSIs and therefore HCV infections should be closely observed.
PMCID: PMC3474162  PMID: 22553942
Healthcare workers; Infections; Tuberculosis; Needlestick injuries; Blood-borne virus infections
2.  The Effects of Influenza Vaccination of Health Care Workers in Nursing Homes: Insights from a Mathematical Model 
PLoS Medicine  2008;5(10):e200.
Annual influenza vaccination of institutional health care workers (HCWs) is advised in most Western countries, but adherence to this recommendation is generally low. Although protective effects of this intervention for nursing home patients have been demonstrated in some clinical trials, the exact relationship between increased vaccine uptake among HCWs and protection of patients remains unknown owing to variations between study designs, settings, intensity of influenza seasons, and failure to control all effect modifiers. Therefore, we use a mathematical model to estimate the effects of HCW vaccination in different scenarios and to identify a herd immunity threshold in a nursing home department.
Methods and Findings
We use a stochastic individual-based model with discrete time intervals to simulate influenza virus transmission in a 30-bed long-term care nursing home department. We simulate different levels of HCW vaccine uptake and study the effect on influenza virus attack rates among patients for different institutional and seasonal scenarios. Our model reveals a robust linear relationship between the number of HCWs vaccinated and the expected number of influenza virus infections among patients. In a realistic scenario, approximately 60% of influenza virus infections among patients can be prevented when the HCW vaccination rate increases from 0 to 1. A threshold for herd immunity is not detected. Due to stochastic variations, the differences in patient attack rates between departments are high and large outbreaks can occur for every level of HCW vaccine uptake.
The absence of herd immunity in nursing homes implies that vaccination of every additional HCW protects an additional fraction of patients. Because of large stochastic variations, results of small-sized clinical trials on the effects of HCW vaccination should be interpreted with great care. Moreover, the large variations in attack rates should be taken into account when designing future studies.
Using a mathematical model to simulate influenza transmission in nursing homes, Carline van den Dool and colleagues find that each additional staff member vaccinated further reduces the risk to patients.
Editors' Summary
Every winter, millions of people catch influenza, a contagious viral disease of the nose, throat, and airways. Most people recover completely from influenza within a week or two but some develop life-threatening complications such as bacterial pneumonia. As a result, influenza outbreaks kill about half a million people—mainly infants, elderly people, and chronically ill individuals—each year. To minimize influenza-related deaths, the World Health Organization recommends that vulnerable people be vaccinated against influenza every autumn. Annual vaccination is necessary because flu viruses continually make small changes to the viral proteins (antigens) that the immune system recognizes. This means that an immune response produced one year provides only partial protection against influenza the next year. To provide maximum protection against influenza, each year's vaccine contains disabled versions of the major circulating strains of influenza viruses.
Why Was This Study Done?
Most Western countries also recommend annual flu vaccination for health care workers (HCWs) in hospitals and other institutions to reduce the transmission of influenza to vulnerable patients. However, many HCWs don't get a regular flu shot, so should efforts be made to increase their rate of vaccine uptake? To answer this question, public-health experts need to know more about the relationship between vaccine uptake among HCWs and patient protection. In particular, they need to know whether a high rate of vaccine uptake by HCWs will provide “herd immunity.” Herd immunity occurs because, when a sufficient fraction of a population is immune to a disease that passes from person to person, infected people rarely come into contact with susceptible people, which means that both vaccinated and unvaccinated people are protected from the disease. In this study, the researchers develop a mathematical model to investigate the relationship between vaccine uptake among HCWs and patient protection in a nursing home department.
What Did the Researchers Do and Find?
To predict influenza virus attack rates (the number of patient infections divided by the number of patients in a nursing home department during an influenza season) at different levels of HCW vaccine uptake, the researchers develop a stochastic transmission model to simulate epidemics on a computer. This model predicts that as the HCW vaccination rate increases from 0 (no HCWs vaccinated) to 1 (all the HCWs vaccinated), the expected average influenza virus attack rate decreases at a constant rate. In the researchers' baseline scenario—a nursing home department with 30 beds where patients come into contact with other patients, HCWs, and visitors—the model predicts that about 60% of the patients who would have been infected if no HCWs had been vaccinated are protected when all the HCWs are vaccinated, and that seven HCWs would have to be vaccinated to protect one patient. This last figure does not change with increasing vaccine uptake, which indicates that there is no level of HCW vaccination that completely stops the spread of influenza among the patients; that is, there is no herd immunity. Finally, the researchers show that large influenza outbreaks can happen by chance at every level of HCW vaccine uptake.
What Do These Findings Mean?
As with all mathematical models, the accuracy of these predictions may depend on the specific assumptions built into the model. Therefore the researchers verified that their findings hold for a wide range of plausible assumptions. These findings have two important practical implications. First, the direct relationship between HCW vaccination and patient protection and the lack of any herd immunity suggest that any increase in HCW vaccine uptake will be beneficial to patients in nursing homes. That is, increasing the HCW vaccination rate from 80% to 90% is likely to be as important as increasing it from 10% to 20%. Second, even 100% HCW vaccination cannot guarantee that influenza outbreaks will not occasionally occur in nursing homes. Because of the large variation in attack rates, the results of small clinical trials on the effects of HCW vaccination may be inaccurate and future studies will need to be very large if they are to provide reliable estimates of the amount of protection that HCW vaccination provides to vulnerable patients.
Additional Information.
Please access these Web sites via the online version of this summary at
Read the related PLoSMedicine Perspective by Cécile Viboud and Mark Miller
A related PLoSMedicine Research Article by Jeffrey Kwong and colleagues is also available
The World Health Organization provides information on influenza and on influenza vaccines (in several languages)
The US Centers for Disease Control and Prevention provide information for patients and professionals on all aspects of influenza (in English and Spanish)
The UK Health Protection Agency also provides information on influenza
MedlinePlus provides a list of links to other information about influenza (in English and Spanish)
The UK National Health Service provides information about herd immunity, including a simple explanatory animation
The European Centre for Disease Prevention and Control provides an overview on the types of influenza
PMCID: PMC2573905  PMID: 18959470
3.  Is Universal HBV Vaccination of Healthcare Workers a Relevant Strategy in Developing Endemic Countries? The Case of a University Hospital in Niger 
PLoS ONE  2012;7(9):e44442.
Exposure to hepatitis B virus (HBV) remains a serious risk to healthcare workers (HCWs) in endemic developing countries owing to the strong prevalence of HBV in the general and hospital populations, and to the high rate of occupational blood exposure. Routine HBV vaccination programs targeted to high-risk groups and especially to HCWs are generally considered as a key element of prevention strategies. However, the high rate of natural immunization among adults in such countries where most infections occur perinatally or during early childhood must be taken into account.
Methodology/Principal Findings
We conducted a cross sectional study in 207 personnel of 4 occupational groups (medical, paramedical, cleaning staff, and administrative) in Niamey’s National Hospital, Niger, in order to assess the prevalence of HBV markers, to evaluate susceptibility to HBV infection, and to identify personnel who might benefit from vaccination. The proportion of those who declared a history of occupational blood exposure ranged from 18.9% in the administrative staff to 46.9% in paramedical staff. Only 7.2% had a history of vaccination against HBV with at least 3 injections. Ninety two percent were anti-HBc positive. When we focused on170 HCWs, only 12 (7.1%) showed no biological HBV contact. Twenty six were HBsAg positive (15,3%; 95% confidence interval: 9.9%–20.7%) of whom 8 (32%) had a viral load >2000 IU/ml.
The very small proportion of HCWs susceptible to HBV infection in our study and other studies suggests that in a global approach to prevent occupational infection by bloodborne pathogens, a universal hepatitis B vaccination of HCWs is not priority in these settings. The greatest impact on the risk will most likely be achieved by focusing efforts on primary prevention strategies to reduce occupational blood exposure. HBV screening in HCWs and treatment of those with chronic HBV infection should be however considered.
PMCID: PMC3436880  PMID: 22970218
4.  High Incidence of Hospital Admissions with Multidrug Resistant and Extensively Drug Resistant Tuberculosis among South African Health Care Workers 
Annals of internal medicine  2010;153(8):516-522.
Nosocomial transmission has been described in extensively drug resistant tuberculosis (XDR-TB) and HIV co-infected patients in South Africa. However, little is known about rates of drug-resistant TB among healthcare workers (HCWs) in TB and HIV endemic settings.
To estimate rates of multi-drug resistant tuberculosis (MDR-TB) and XDR-TB hospitalizations among HCWs in KwaZulu-Natal (KZN), South Africa.
Retrospective study of drug-resistant TB patients admitted for the initiation of drug-resistant TB therapy between 2003 and 2008.
A public TB referral hospital in KZN, South Africa.
HCWs admitted with MDR-TB (N=203) or XDR-TB (N=28) were compared with non-HCWs admitted with MDR-TB (N=3807) or XDR-TB (N=344).
Hospital admission rates, hospital admission incidence rate ratios.
Estimated incidence of MDR-TB hospitalization was 64.8/100,000 for HCWs versus 11.9/100,000 for non-HCWs (I.R.R. 5.56 95% C.I. 4.87–6.35). Estimated incidence of XDR-TB hospitalizations was 7.2/100,000 among HCWs versus 1.1/100,000 in non-HCWs (I.R.R. 6.69 95% C.I. 4.38–10.20). A higher percentage of HCWs than non-HCWs with MDR-TB or XDR-TB were female (78% vs. 47%, p<0.001) and fewer HCWs reported previous TB treatment (41% vs. 92%, p<0.001). Prevalence of HIV infection did not differ between HCW and non-HCW (55% vs. 57%, p=0.71), but a higher percentage of HIV infected HCWs were on antiretroviral medications (63% vs. 47%, p<0.001).
HCWs in this HIV-endemic area were substantially more likely to be hospitalized with either MDR-TB or XDR-TB compared to non-HCWs. The increased risk may be explained by occupational exposure and not by other risk factors, underlining the urgent need for TB infection control programs.
Primary Funding Source
No funding was received for this study
PMCID: PMC3074259  PMID: 20956708
5.  Influenza and hepatitis B vaccination coverage among healthcare workers in Croatian hospitals: a series of cross-sectional surveys, 2006–2011 
BMC Infectious Diseases  2013;13:520.
Healthcare workers (HCWs) are at an increased risk of exposure to and transmission of infectious diseases. Vaccination lowers morbidity and mortality of HCWs and their patients. To assess vaccination coverage for influenza and hepatitis B virus (HBV) among HCWs in Croatian hospitals, we conducted yearly nationwide surveys.
From 2006 to 2011, all 66 Croatian public hospitals, representing 43–60% of all the HCWs in Croatia, were included. Statistical analysis was performed using the Kruskal–Wallis analysis of variance, Dunn’s multiple comparison analysis and the chi-square test, as appropriate.
The median seasonal influenza vaccination coverage rates in pre-pandemic (2006–2008) seasons were 36%, 25% and 29%, respectively. By occupation, influenza vaccination rates among physicians were 33 ± 21%, 33 ± 22% among graduate nurses, 30±34% among other HCWs, 26 ± 21% among housekeeping and the lowest, 23 ± 17%, among practical nurses (p < 0.01). In 2009–2010 season, seasonal influenza vaccination coverage was 30%, while overall vaccination coverage against pandemic influenza was fewer than 5%. Median vaccination coverage in the post-pandemic seasons of 2010–2011 and 2011–2012 decreased to 15% and 14%, respectively (reduction of 24% and 35%, respectively, p < 0.0001). Meanwhile, the median mandatory HBV vaccination coverage was 98%, albeit with considerable differences according to work setting (range 19–100%) and occupation (range 4–100%).
We found substantial year-on-year variations in seasonal influenza vaccination rates, with reduction in post pandemic influenza seasons. HBV vaccination is satisfactory compared to seasonal influenza vaccination coverage, although substantial variations by occupation and work setting were observed. These findings highlight the need for national strategies that optimize vaccination coverage among HCWs in Croatian hospitals. Further studies are needed to establish the potential role of mandatory vaccination for seasonal influenza.
PMCID: PMC3840606  PMID: 24192278
Influenza; Hepatitis B; Healthcare workers; Vaccination
6.  Incidence of occupational exposures in a tertiary health care center 
Occupational exposure to Hepatitis B virus (HBV), human immunodeficiency virus (HIV) and Hepatitis C virus (HCV) infection is a cause of concern to all health care workers (HCWs), especially those, in hospitals. Among the HCWs, nurses, interns, technicians, resident doctors and housekeeping staff have the highest incidence of occupational exposure.
To analyze the cases of needle stick injuries and other exposures to patient's blood or body fluids among health care workers.
Materials and Methods:
A detailed account of the exposure is documented which includes incidence of needle stick injuries (NSI) and implementation of post-exposure prophylaxis (PEP) as per the hospital guidelines. We report a two-year continuing surveillance study where 255 health care workers (HCWs) were included. PEP was given to HCWs sustaining NSI or exposures to blood and body fluids when the source is known sero-positive or even unknown where the risk of transmission is high. Follow-up of these HCW's was done after three and six months of exposure.
Of the 255 HCWs, 59 sustained needle stick injuries and two were exposed to splashes. 31 of the NSI were from known sources and 28 from unknown sources. From known sources, thirteen were seropositive; seven for HIV, three for HCV and three for HBV. Nineteen of them sustained needle stick during needle re-capping, six of them during clean up, six of them while discarding into the container, 17 during administration of injection, eight of them during suturing, two occurred in restless patient, 17 during needle disposal.
So far, no case of sero-conversion as a result of needle stick injuries was reported at our center.
PMCID: PMC3505302  PMID: 23188932
Human immunodeficiency virus; hepatitis B and C virus; Occupational exposure; post-exposure prophylaxis
7.  Occupational exposure to body fluids among health care workers in Georgia 
Health care workers (HCWs) are at increased risk of being infected with blood-borne pathogens.
To evaluate risk of occupational exposure to blood-borne viruses and determine the prevalence of human immunodeficiency virus (HIV), hepatitis B virus (HBV) and hepatitis C virus (HCV) among HCWs in Georgia.
The sample included HCWs from seven medical institutions in five cities in Georgia. A self-administered questionnaire was used to collect information on demographic, occupational and personal risk factors for blood-borne viruses. After obtaining informed consent, blood was drawn from the study participants for a seroprevalence study of HBV, HCV and HIV infections.
There were 1386 participating HCWs from a number of departments, including surgery (29%), internal medicine (19%) and intensive care (19%). Nosocomial risk events were reported by the majority of HCWs, including accidental needlestick injury (45%), cuts with contaminated instruments (38%) and blood splashes (46%). The most frequent risk for receiving a cut was related to a false move during a procedure, reassembling devices and handing devices to a colleague. The highest proportion of needlestick injuries among physicians (22%) and nurses (39%) was related to recapping of used needles. No HIV-infected HCW was identified. Prevalence of HCV infection was 5%, anti-HBc was present among 29% with 2% being HBsAg carriers.
Data from this study can be utilized in educational programs and implementation of universal safety precautions for HCWs in Georgia to help achieve similar reductions in blood-borne infection transmission to those achieved in developed countries.
PMCID: PMC3612004  PMID: 22869786
Blood-borne virus; contamination injury; developing country; needlestick
8.  Long-Term Persistence of Seroprotection by Hepatitis B Vaccination in Healthcare Workers of Southern Italy 
Hepatitis Monthly  2012;12(9):e6025.
The impact of hepatitis B virus (HBV) vaccination campaigns on HBV epidemiology needs to be evaluated, in order to assess the long-term immunity offered by vaccines against HBV.
To evaluate the current status of anti-HBV vaccine coverage among healthcare workers (HCWs) in Southern Italy, and to determine the long-term persistence of antibodies to hepatitis B surface antigens (anti-HBs) in such a cohort of subjects.
Patients and Methods
A longitudinal, retrospective seroepidemiological survey was conducted among 451 HCWs, who were working at or visiting, the Occupational Health Department of a city hospital, in Catania, Italy, between January 1976 and December 2010.
At the 30-year follow-up (mean follow-up 10.15 ± 5.96 years, range 0.74-30), 261 HCWs had detectable anti-HBs titers indicating a persistence of seroprotection of 89.4% (out of 292 anti-HBs positive results, three months after vaccination). An inadequate vaccination schedule was the strongest predictor of antibody loss during follow-up (OR = 8.37 95% CI: 5.41-12.95, P < 0.001). A Kaplan-Maier survival curve revealed that the persistence of anti-HBs 30 years after vaccination, was 92.2% for high responders, while it was only 27.3% for low responders (P = 0.001).
A good level of seroprotection persisted in 57.9% of the subjects after 30 years. Factors related to this immunization status confirmed the importance of vaccinating HCWs early in their careers and ensuring an adequate vaccination schedule. However, with particular reference to the low rate of hepatitis B vaccine coverage among HCWs in Southern Italy, the implementation of a new educational intervention as part of an active vaccination program is needed.
PMCID: PMC3475028  PMID: 23087756
Hepatitis B Virus; Vaccines; Health Personnel; Vaccination
9.  Occupational Exposure to Blood and Body Fluids among Health Care Workers in Teaching Hospitals in Tehran, Iran 
Health care workers (HCWs) are vulnerable populations for infection with blood borne pathogens. This study was conducted to determine occupational exposure to blood and body fluids among HCWs in teaching hospitals in Tehran, Iran.
A self-structures questionnaire was used to study 650 HCWs during 2006 -2007 in some teaching hospitals in Tehran, Iran.
occupational exposure to blood and body fluids to blood and body fluids of patients was noticed in 53.4%. Recapping was the most common cause of niddle stick injuries (26.5%) and 19.9% of HCWs with a history of needlestick or mucosal exposure had sought medical advice from a specialist, 79.4% of these visited a doctor in the first 24 hours after exposure. Twenty percent of people with a history of needlestick or mucosal exposure to human immune deficiency virus positive (HIV+) patients received post-exposure prophylaxis and 46.7% tested themselves for seroconversion. 25.8% of HCWs with a history of needlestick or mucosal exposure with HBsAg+ patients received hepatitis B immunoglobuline (HBIG), all of these had received it in the first 72 hours after exposure. History of vaccination, and reassurance about the effective serum antibody titer was the most frequent reason mentioned in case the individuals did not receive HBIG (56.5%).
There is a need for further research to investigate why many HCWs do not take prophylactic and essential actions after needle stick or mucosal exposure to body fluids of infected patients.
PMCID: PMC3438432  PMID: 22997555
Needlestick injuries; Health care workers; Blood borne pathogens
10.  Prevalence of measles antibodies among health care workers in Catalonia (Spain) in the elimination era 
BMC Infectious Diseases  2013;13:391.
Interruption of measles transmission was achieved in Catalonia (Spain) in 2000. Six years later, a measles outbreak occurred between August 2006 and June 2007 with 381 cases, 11 of whom were health care workers (HCW).
The objective was to estimate susceptibility to measles in HCW and related demographic and occupational characteristics.
A measles seroprevalence study was carried out in 639 HCW from six public tertiary hospitals and five primary healthcare areas. Antibodies were tested using the Vircell Measles ELISA IgG Kit. Data were analyzed according to age, sex, type of HCW, type of centre and vaccination history.
The odds ratios (OR) and their 95% CI were calculated to determine the variables associated with antibody prevalence. OR were adjusted using logistic regression.
Positive predictive values (PPV) and the 95% confidence intervals (CI) of having two documented doses of a measles containing vaccine (MCV) for the presence of measles antibodies and of reporting a history of measles infection were calculated.
The prevalence of measles antibodies in HCW was 98% (95% CI 96.6-98.9), and was lower in HCW born in 1981 or later, after the introduction of systematic paediatric vaccination (94.4%; 95% CI 86.4-98.5) and higher in HCW born between 1965 and 1980 (99.0%; 95% CI 97.0-99.8). Significant differences were found for HCW born in 1965–1980 with respect to those born in 1981 and after (adjusted OR of 5.67; 95% CI: 1.24-25.91).
A total of 187 HCW reported being vaccinated: the proportion of vaccinated HCW decreased with age. Of HCW who reported being vaccinated, vaccination was confirmed by the vaccination card in 49%. Vaccination with 2 doses was documented in only 50 HCW, of whom 48 had measles antibodies. 311 HCW reported a history of measles.
The PPV of having received two documented doses of MCV was 96% (95% CI 86.3-99.5) and the PPV of reporting a history of measles was 98.7% (95% CI 96.7-99.6).
Screening to detect HCW who lack presumptive evidence of immunity and vaccination with two doses of vaccine should be reinforced, especially in young workers, to minimize the risk of contracting measles and infecting the susceptible patients they care for.
PMCID: PMC3765384  PMID: 23978316
Measles; Seroprevalence; Health care workers; MCV vaccination
11.  Did the pandemic have an impact on influenza vaccination attitude? a survey among health care workers 
Health care workers' (HCWs) influenza vaccination attitude is known to be negative. The H1N1 epidemic had started in mid 2009 and made a peak in October-November in Turkey. A national vaccination campaign began on November 2nd, 2009. Despite the diligent efforts of the Ministry of Health and NGOs, the attitudes of the media and politicians were mostly negative. The aim of this study was to evaluate whether HCWs' vaccination attitudes improved during the pandemic and to assess the related factors.
This cross-sectional survey was carried out at the largest university hospital of the Aegean Region-Turkey. A self-administered questionnaire with 12 structured questions was applied to 807 HCWs (sample coverage 91.3%) before the onset of the vaccination programme. Their final vaccination status was tracked one week afterwards, using immunization records. Factors influencing vaccination rates were analyzed using ANOVA, t-test, chi-square test and logistic regression.
Among 807 participants, 363 (45.3%) were doctors and 293 (36.6%) nurses. A total of 153 (19.0%) had been vaccinated against seasonal influenza in the 2008-2009 season. Regarding H1N1 vaccination, 143 (17.7%) were willing to be vaccinated vs. 357 (44.2%) unwilling. The number of indecisive HCWs was 307 (38.0%) one week prior to vaccination. Only 53 (11.1%) stated that they would vaccinate their children. Possible side effects (78%, n = 519) and lack of comprehensive field evaluation before marketing (77%, n = 508) were the most common reasons underlying unwillingness or hesitation.
Among the 749 staff whose vaccination status could be tracked, 228 (30.4%) actually received the H1N1 vaccine. Some of the 'decided' staff members had changed their mind one week later. Only 82 (60%) of those willing, 108 (37%) of those indecisive and 38 (12%) of those unwilling were vaccinated.
Indecisive HCWs were significantly younger (p = 0.017). Females, nurses, and HCWs working in surgical departments were more likely to reject vaccination (p < 0.05). Doctors, HCWs working in medical departments, and HCWs previously vaccinated against seasonal influenza were more likely to accept vaccination (p < 0.05). Being younger than 50 and having been vaccinated in the previous season were important predictors of attitude towards pandemic influenza vaccination.
Vaccination rates increased substantially in comparison to the previous influenza season. However, vaccination rates could have been even higher since hesitation to be vaccinated increased dramatically within one week (only 60% of those willing and the minority of those indecisive were finally vaccinated). We speculate that this may be connected with negative media at the time.
PMCID: PMC3084177  PMID: 21473763
12.  Seroprevalence of hepatitis B and C virus infections among health students and health care workers in the Najran region, southwestern Saudi Arabia: The need for national guidelines for health students 
BMC Public Health  2014;14:577.
The objectives of the study were to study the seroprevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections among health college students (HS) and health care workers (HCWs) in the Najran Region of south-western Saudi Arabia and to study the students’ knowledge of occupational exposure to blood-borne viral infections.
A cross-sectional study of a representative sample of 300 HS and 300 HCWs was conducted.
An overall seroprevalence of HBV of 1.7% and 8.7% was found among HS and HCWs, respectively. Two-thirds of HS (66.7%, 200) and 23.3% (70) of HCWs lack anti-HBs and are susceptible to HBV infection. An overall seroprevalence of HCV of 0% and 0.3% was found among the HS and HCWs, respectively. The present study indicates poor knowledge among HS and moderate knowledge among HCWs regarding occupationally transmitted blood-borne diseases, safe injection practices, and standard precautions to prevent occupationally transmitted blood-borne infections.
It is mandatory to develop a structured program to raise awareness among HS, and current health colleges’ curricula should be upgraded to address these issues early. The HS should be considered new recruits to health services in terms of their initial screening for blood-borne infections and vaccination against HBV. The development of a novel continuing medical education and pre-employment awareness program for HCWs is recommended to address the following: blood-borne diseases transmitted occupationally, standard precautions to prevent occupationally transmitted blood borne infections, and safe injection practices.
PMCID: PMC4059075  PMID: 24912684
HBV; HCV; HCW; Health Students; Saudi Arabia
13.  Self-reported occupational exposure to HIV and factors influencing its management practice: a study of healthcare workers in Tumbi and Dodoma Hospitals, Tanzania 
Blood borne infectious agents such as hepatitis B virus (HBV), hepatitis C virus (HCV) and human immune deficiency virus (HIV) constitute a major occupational hazard for healthcare workers (HCWs). To some degree it is inevitable that HCWs sustain injuries from sharp objects such as needles, scalpels and splintered bone during execution of their duties. However, in Tanzania, there is little or no information on factors that influence the practice of managing occupational exposure to HIV by HCWs. This study was conducted to determine the prevalence of self-reported occupational exposure to HIV among HCWs and explore factors that influence the practice of managing occupational exposure to HIV by HCWs in Tanzania.
Self-administered questionnaire was designed to gather information of healthcare workers’ occupational exposures in the past 12 months and circumstances in which these injuries occurred. Practice of managing occupational exposure was assessed by the following questions:
Nearly half of the HCWs had experienced at least one occupational injury in the past 12 months. Though most of the occupational exposures to HIV were experienced by female nurses, non-medical hospital staff received PEP more frequently than nurses and doctors. Doctors and nurses frequently encountered occupational injuries in surgery room and labor room respectively. HCWs with knowledge on the possibility of HIV transmission and those who knew whom to contact in event of occupational exposure to HIV were less likely to have poor practice of managing occupational exposure.
Needle stick injuries and splashes are common among HCWs at Tumbi and Dodoma hospitals. Knowledge of the risk of HIV transmission due to occupational exposure and knowing whom to contact in event of exposure predicted practice of managing the exposure. Thus provision of health education on occupational exposure may strengthen healthcare workers’ practices to manage occupational exposure.
PMCID: PMC3718638  PMID: 23866940
HIV; Occupational exposure; Healthcare workers
14.  A Surveillance System to Reduce Transmission of Pandemic H1N1 (2009) Influenza in a 2600-Bed Medical Center 
PLoS ONE  2012;7(3):e32731.
Concerns have been raised about how the transmission of emerging infectious diseases from patients to healthcare workers (HCWs) and vice versa could be recognized and prevented in a timely manner. An effective strategy to block transmission of pandemic H1N1 (2009) influenza in HCWs is important.
Methodology/Principal Findings
An infection control program was implemented to survey and prevent nosocomial outbreaks of H1N1 (2009) influenza at a 2,600-bed, tertiary-care academic hospital. In total, 4,963 employees at Kaohsiung Chang Gung Memorial Hospital recorded their temperature and received online education on control practices for influenza infections. Administration records provided vaccination records and occupational characteristics of all HCWs. Early recognition of a pandemic H1N1 (2009) influenza case was followed by a semi-structured questionnaire to analyze possible routes of patient contact, household contact, or unspecified contact. Surveillance spanned August 1, 2009 to January 31, 2010; 51 HCWs were confirmed to have novel H1N1 (2009) influenza by quantitative real-time reverse transcription polymerase chain reaction. Prevalence of patient contact, household contact, or unspecified contact infection was 13.7% (7/51), 13.7% (7/51), and 72.5% (37/51), respectively. The prevalence of the novel H1N1 infection was significantly lower among vaccinated HCWs than among unvaccinated HCWs (p<0.001). Higher viral loads in throat swabs were found in HCWs with patient and household contact infection than in those with unspecified contact infection (4.15 vs. 3.53 copies/mL, log10, p = 0.035).
A surveillance system with daily temperature recordings and online education for HCWs is important for a low attack rate of H1N1 (2009) influenza transmission before H1N1 (2009) influenza vaccination is available, and the attack rate is further decreased after mass vaccination. Unspecified contact infection rates were significantly higher than that of patient contact and household contact infection, highlighting the need for public education of influenza transmission in addition to hospital infection control.
PMCID: PMC3302803  PMID: 22427871
15.  Protecting patients, protecting healthcare workers: a review of the role of influenza vaccination 
International Nursing Review  2011;59(2):161-167.
MUSIC T. (2012) A review of the role the role of influenza vaccination in protecting patients, protecting healthcare workers the role of influenza vaccination. International Nursing Review59, 161–167
Many health authorities recommend routine influenza vaccination for healthcare workers (HCWs), and during the 2009 A (H1N1) pandemic, the World Health Organization (WHO) recommended immunization of all HCWs worldwide. As this remains an important area of policy debate, this paper examines the case for vaccination, the role of local guidelines, barriers to immunization and initiatives to increase uptake.
Seasonal influenza is a major threat to public health, causing up to 1 million deaths annually. Extensive evidence supports the vaccination of priority groups, including HCWs. Immunization protects HCWs themselves, and their vulnerable patients from nosocomial influenza infections. In addition, influenza can disrupt health services and impact healthcare organizations financially. Immunization can reduce staff absences, offer cost savings and provide economic benefits.
This paper reviews official immunization recommendations and HCW vaccination studies, including a recent International Federation of Pharmaceutical Manufacturers and Associations (IFPMA) survey of 26 countries from each region of the world.
HCW immunization is widely recommended and supported by the WHO. In the IFPMA study, 88% of countries recommended HCW vaccination, and 61% supported this financially (with no correlation to country development status). Overall, coverage can be improved, and research shows that uptake may be impacted by lack of conveniently available vaccines and misconceptions regarding vaccine safety/efficacy and influenza risk.
Many countries recommend HCW vaccination against influenza. In recent years, there has been an increased uptake rate among HCWs in some countries, but not in others. Several initiatives can increase coverage, including education, easy access to free vaccines and the use of formal declination forms. The case for HCW vaccination is clear, and in an effort to further accelerate uptake as a patient safety measure, an increasing number of healthcare organizations, particularly in the USA, are implementing mandatory immunization policies, similar to other obligatory hygiene measures. However, it would be desirable if similar high vaccination uptake rates could be achieved through voluntary procedures.
PMCID: PMC3418836  PMID: 22591085
Coverage; Education; Guideline; Influenza; Policy; Recommendation; Reimbursement; Seasonal; Vaccine
16.  Evaluation of immune response to Hepatitis B vaccine in health care workers at a tertiary care hospital in Pakistan: an observational prospective study 
Seroconversion rates reported after Hepatitis B virus (HBV) vaccination globally ranges from 85–90%. Health care workers (HCWs) are at high risk of acquiring HBV and non responders' rates after HBV vaccination were not reported previously in Pakistani HCWs. Therefore we evaluated immune response to HBV vaccine in HCWs at a tertiary care hospital in Karachi, Pakistan.
Descriptive observational study conducted at Aga Khan University from April 2003 to July 2004. Newly HBV vaccinated HCWs were evaluated for immune response by measuring serum Hepatitis B surface antibody (HBsAb) levels, 6 weeks post vaccination.
Initially 666 employees were included in the study. 14 participants were excluded due to incomplete records. 271 (41%) participants were females and 381(59%) were males. Majority of the participants were young (<25–39 years old), regardless of gender. Out of 652 HCWs, 90 (14%) remained seronegative after six weeks of post vaccination. The percentage of non responders increased gradually from 9% in participants of <25, 13% in 25–34, 26% in 35–49, and 63% in >50 years of age. Male non responders were more frequent (18%) than female (8%).
Seroconversion rate after HBV vaccination in Pakistani HCWs was similar to that reported in western and neighboring population. HCWs with reduced immune response to HBV vaccine in a high disease prevalent population are at great risk. Therefore, it is crucial to check post vaccination HBsAb in all HCWs. This strategy will ensure safety at work by reducing nosocomial transmission and will have a cost effective impact at an individual as well as at national level, which is very much desired in a resource limited country.
PMCID: PMC2228304  PMID: 17961205
17.  Frequent Transient Hepatitis C viremia without Seroconversion among Healthcare Workers in Cairo, Egypt 
PLoS ONE  2013;8(2):e57835.
With 10% of the general population aged 15–59 years chronically infected with hepatitis C virus (HCV), Egypt is the country with the highest HCV prevalence worldwide. Healthcare workers (HCWs) are therefore at particularly high risk of HCV infection. Our aim was to study HCV infection risk after occupational blood exposure among HCWs in Cairo.
Methodology/Principal Findings
The study was conducted in 2008–2010 at Ain Shams University Hospital, Cairo. HCWs reporting an occupational blood exposure at screening, having neither anti-HCV antibodies (anti-HCV) nor HCV RNA, and exposed to a HCV RNA positive patient, were enrolled in a 6-month prospective cohort with follow-up visits at weeks 2, 4, 8, 12 and 24. During follow-up, anti-HCV, HCV RNA and ALT were tested. Among 597 HCWs who reported a blood exposure, anti-HCV prevalence at screening was 7.2%, not different from that of the general population of Cairo after age-standardization (11.6% and 10.4% respectively, p = 0.62). The proportion of HCV viremia among index patients was 37%. Of 73 HCWs exposed to HCV RNA from index patients, nine (12.3%; 95%CI, 5.8–22.1%) presented transient viremia, the majority of which occurred within the first two weeks after exposure. None of the workers presented seroconversion or elevation of ALT.
HCWs of a general University hospital in Cairo were exposed to a highly viremic patient population. They experienced frequent occupational blood exposures, particularly in early stages of training. These exposures resulted in transient viremic episodes without established infection. These findings call for further investigation of potential immune protection against HCV persistence in this high risk group.
PMCID: PMC3585182  PMID: 23469082
18.  Prevalence of HBV and HBV vaccination coverage in health care workers of tertiary hospitals of Peshawar, Pakistan 
Virology Journal  2011;8:275.
Hepatitis B Virus (HBV) may progress to serious consequences and increase dramatically beyond endemic dimensions that transmits to or from health care workers (HCWs) during routine investigation in their work places. Basic aim of this study was to canvass the safety of HCWs and determine the prevalence of HBV and its possible association with occupational and non-occupational risk factors. Hepatitis B vaccination coverage level and main barriers to vaccination were also taken in account.
A total of 824 health care workers were randomly selected from three major hospitals of Peshawar, Khyber Pakhtunkhwa. Blood samples were analyzed in Department of Zoology, Kohat University of Science and Technology Kohat, and relevant information was obtained by means of preset questionnaire. HCWs in the studied hospitals showed 2.18% prevalence of positive HBV. Nurses and technicians were more prone to occupational exposure and to HBV infection. There was significant difference between vaccinated and non-vaccinated HCWs as well as between the doctors and all other categories. Barriers to complete vaccination, in spite of good knowledge of subjects in this regard were work pressure (39.8%), negligence (38.8%) un-affordability (20.9%), and unavailability (0.5%).
Special preventive measures (universal precaution and vaccination), which are fundamental way to protect HCW against HBV infection should be adopted.
PMCID: PMC3121707  PMID: 21645287
19.  Knowledge, Attitudes and Practice of Iranian Medical Specialists regarding Hepatitis B and C 
Hepatitis Monthly  2010;10(3):176-182.
Background and Aims
Health care workers (HCWs) are at risk of contracting and spreading hepatitis B virus (HBV) and hepatitis C virus (HCV) to others. The aim of this study was to evaluate knowledge, attitudes and behavior of physicians concerning HBV and HCV.
A 29-item questionnaire (reliability coefficient = 0.7) was distributed at two national/regional congresses and two university hospitals in Iran. Five medical groups (dentists, general practitioners, paraclinicians, surgeons and internists) received 450 questionnaires in 2009, of which 369 questionnaires (82%) were filled out.
Knowledge about routes of transmission of HBV and HCV, prevalence rate and seroconversion rates secondary to a needlestick injury was moderate to low. Concern about being infected with HBV and HCV was 69.4±2.1 and 76.3±2 (out of 100), respectively. Complete HBV vaccination was done on 88.1% of the participants. Sixty percent had checked their hepatitis B surface antibody (anti-HBs), and 83.8% were positive. Only 24% of the surgeons often used double gloves and 28% had reported a needlestick. There was no significant correlation between the different specialties and: concern about HBV and HCV; the underreporting of needlestick injuries; and correct knowledge of post-needlestick HBV infection.
Although our participants were afraid of acquiring HBV and HCV, knowledge about routes of transmission, prevalence, protection and post-exposure seroconversion rates was unsatisfactory. By making physicians aware of possible post-exposure prophylaxis, the underreporting of needlestick injuries could be eliminated. Continuous training about HBV and HCV transmission routes, seroconversion rates, protection, as well as hepatitis B vaccination and checking the anti-HBs level, is a matter of necessity.
PMCID: PMC3269081  PMID: 22308136
Hepatitis B; Hepatitis C; Health Knowledge; Attitudes; Practices; Iran
20.  Predictive factors associated with the acceptance of pandemic and seasonal influenza vaccination in health care workers and students in Tuscany, Central Italy 
Human Vaccines & Immunotherapeutics  2013;9(12):2603-2612.
Assessing the beliefs and attitudes of Health Care Workers (HCW) to influenza and influenza vaccination can be useful in overcoming low compliance rates. The purpose of our study is to evaluate the opinion of HCW and students regarding influenza, influenza vaccine and the factors associated with vaccination compliance. A survey was conducted between October 2010 and April 2011 in the Florence metropolitan area. A questionnaire was administered to HCW in three local healthcare units and at Careggi University Teaching Hospital. Students matriculating in health degree programs at Florence University were also surveyed.
The coverage with vaccination against seasonal and pandemic influenza is generally low, and it is lower in students than in HCW (12.5% vs 15% for the seasonal vaccination, 8.5% vs 18% for the pandemic vaccination). Individuals comply with vaccination offer mainly to protect themselves and their contacts. Individuals not receiving vaccination did not consider themselves at risk, had never been vaccinated before or believed that pandemic influenza was not a public health concern. Physicians had the highest compliance to vaccination and women were less frequently vaccinated than men. HCW do not appear to perceive their possible influenza infections as a risk for patients: HCW receive vaccination mainly as a form of personal protection.
Low compliance to vaccination is determined by various factors and therefore requires a multi-faceted strategy of response. This should include short-term actions to overcome organizational barriers, in addition to long-term interventions to raise HCW’s level of knowledge about influenza and influenza vaccination.
PMCID: PMC4162047  PMID: 23954990
attitudes towards vaccine; vaccine policy; health care workers; influenza; H1N1; pandemic
21.  Stigmatization of people living with HIV/AIDS by healthcare workers at a tertiary hospital in KwaZulu-Natal, South Africa: a cross-sectional descriptive study 
BMC Medical Ethics  2013;14(Suppl 1):S6.
The issue of stigma is very important in the battle against HIV/AIDS in Africa since it may affect patient attendance at healthcare centres for obtaining antiretroviral (ARV) medications and regular medical check-ups. Stigmatization creates an unnecessary culture of secrecy and silence based on ignorance and fear of victimization. This study was designed to determine if there is external stigmatization of people living with HIV and AIDS (PLWHA) by health care workers (HCWs) at a tertiary hospital in KwaZulu-Natal (KZN) province, South Africa. The study investigated the impact of knowledge of HIV/AIDS by HCWs on treatment of patients, as well as the comfort level and attitude of HCWs when rendering care to PLWHA.
A descriptive cross sectional study was designed to collect data using an anonymous self-administered structured questionnaire from 334 HCWs. The study was conducted in clinical departments of a large multidisciplinary 922-bed tertiary care teaching hospital in Durban, KZN.
Overall HCWs had an above average knowledge about HIV/AIDS although some gaps in knowledge were identified. Tests of statistical significance showed that there was association between level of education and knowledge of HIV/AIDs (p ≤ 0.001); occupation and knowledge of HIV/AIDS (p ≤ 0.001); and gender and knowledge of HIV/AIDS (p = 0.004). Test for comfort level was only significant for gender, with males showing more comfort and empathy when dealing with PLWHA (p = 0.003). The study also revealed that patients were sometimes tested for HIV without informed consent before surgery, due to fear of being infected, and there was some gossiping about patients' HIV status by HCWs, thereby compromising patient confidentiality. The majority of HCWs showed a willingness to report incidents of stigmatization and discrimination to higher authorities, for better monitoring and control.
Although knowledge, attitude and comfort level of HCWs taking care of PLWHA was above average, enforcement of existing antidiscrimination laws and continuing education in medical ethics and healthcare law, would greatly improve the performance of HCWs taking care of PLWHAs. More psychological support and counselling should be provided to HCWs, to further reduce the impact of stigmatization and discrimination against PLWHA.
PMCID: PMC3878339  PMID: 24564982
HIV/AIDS; Africa; Attitude; Comfort; Discrimination; Healthcare workers; PLWHA; Stigmatization
22.  Infection Control and Practice of Standard Precautions Among Healthcare Workers in Northern Nigeria 
Healthcare-associated infections (HAIs) have been reported to be a serious problem in the healthcare services as they are common causes of illness and mortality among hospitalized patients including healthcare workers (HCWs). Compliance with these standard precautions has been shown to reduce the risk of exposure to blood and body fluids.
This study therefore assesses the level of knowledge and compliance with standard precautions by the various cadre of HCWs and the factors influencing compliance in hospital environment in Nasarawa State, Northern Nigeria.
Settings and Design:
Nasarawa State has a current human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) prevalence rate of 10.0%, which was higher than most states in Nigeria with a high level of illiteracy and ignorance. Majority of the people reside in the rural areas while a few are found in the towns, informal settlements with no direct access to healthcare facilities are common.
Materials and Methods:
This study is an analytical, cross-sectional study. Proportional sampling technique was used to obtain a representative sample and a structured self-administered questionnaire was used to collect relevant information from the healthcare providers working in Nasarawa State from January to February 2009.
Statistical analysis used:
To describe patient characteristics, we calculated proportions and medians. For categorical variables, we compared proportions using chi-square tests. A logistic regression model was produced with infection control as outcome variable to identify associated factors.
A total of 421 HCWs were interviewed, Majority (77.9%) correctly describe universal precaution and infection control with 19.2, 19.2, and 28.0%, respectively unable to recognize vaccination, postexposure prophylaxis, and surveillance for emerging diseases as standard precaution for infection control. About 70.1% usually wear gloves before handling patients or patients’ care products, 12.6% reported wash their hand before wearing the gloves, 10.7% washed hands after removal of gloves, and 72.4% changed gloves after each patient. Only 3.3% had a sharp disposal system in their various workplaces. Majority (98.6%) of the respondents reported that the major reason for noncompliance to universal precautions is the nonavailability of the equipments. There was a statistically significant difference in the practice of standard precaution among those that were exposed to blood products and body fluid compared to those that had not been exposed in the last 6 months (χ2 = 3.96, P = 0.03), public healthcare providers when compared to private health workers (χ2 = 22.32, P = 0.001), among those working in secondary and tertiary facilities compared to primary healthcare centers (χ2 = 14.64, P = 0.001) and urban areas when compared to rural areas (χ2 = 4.06, P = 0.02). The only predictor of practice of standard precaution was exposure to blood and body fluid in the last 6 months odds ratio (OR) = 4.56 (confidence interval (CI) = 1.00-21.28).
This study implies that inadequate workers’ knowledge and environment related problems, including the lack of protective materials and other equipments and utilities required to ensure safety of HCWs is a crucial issue that need urgent attention. Institution of a surveillance system for hospital acquired infection to improve consistent use of standard precautions among health workers is recommended in Nigeria and other low income countries in Africa.
PMCID: PMC3958986  PMID: 24672178
Health workers; Infection control; Northern Nigeria; Standard precaution practice
23.  Effects of Training Course on Occupational Exposure to Bloodborne Pathogens: A Controlled Interventional Study 
One of the serious occupational concerns in health care workers (HCWs) is exposure to blood/body fluids that can transmit blood borne pathogens such as human immunodeficiency virus and hepatitis B and C viruses. We are reporting the effects of training course and surveillance on the rate of needle stick injuries (NSIs) among HCWs at an educational hospital in Iran.
To evaluate the effects of training course on the rate of NSIs and its reporting.
We selected two hospitals (A&B) based on their similarities in wards and facilities then asked the managers of these two hospitals to participate in our study. We established a new occupational health center and conducted a training course at hospital A on 2010 and compared it with control group (hospital B). The data from 2009 to 2011 was collected, analyzed to compare pre and post intervention rates.
During study period nurses sustained the highest number of injuries (hospital A: n=80; 66.1% and hospital B: n=64; 35.4%). The incidence rate of NSIs in hospital A was 7.16 NSI/100FTE/YEAR before the intervention which was increased to 12.06 after the intervention. In hospital B this rate was 6.05 during three years.
The study revealed remarkable increase in the incidence rate of NSIs after the intervention. This is being achieved by meticulous surveillance, training course and improving awareness
PMCID: PMC3883246  PMID: 24404356
Bloodborne pathogens; health care workers; needle stick injuries
24.  Healthcare workers and health care-associated infections: knowledge, attitudes, and behavior in emergency departments in Italy 
This survey assessed knowledge, attitudes, and compliance regarding standard precautions about health care-associated infections (HAIs) and the associated determinants among healthcare workers (HCWs) in emergency departments in Italy.
An anonymous questionnaire, self-administered by all HCWs in eight randomly selected non-academic acute general public hospitals, comprised questions on demographic and occupational characteristics; knowledge about the risks of acquiring and/or transmitting HAIs from/to a patient and standard precautions; attitudes toward guidelines and risk perceived of acquiring a HAI; practice of standard precautions; and sources of information.
HCWs who know the risk of acquiring Hepatitis C (HCV) and Human Immunodeficiency Virus (HIV) from a patient were in practice from less years, worked fewer hours per week, knew that a HCW can transmit HCV and HIV to a patient, knew that HCV and HIV infections can be serious, and have received information from educational courses and scientific journals. Those who know that gloves, mask, protective eyewear, and hands hygiene after removing gloves are control measures were nurses, provided care to fewer patients, knew that HCWs' hands are vehicle for transmission of nosocomial pathogens, did not know that a HCW can transmit HCV and HIV to a patient, and have received information from educational courses and scientific journals. Being a nurse, knowing that HCWs' hands are vehicle for transmission of nosocomial pathogens, obtaining information from educational courses and scientific journals, and needing information were associated with a higher perceived risk of acquiring a HAI. HCWs who often or always used gloves and performed hands hygiene measures after removing gloves were nurses, provided care to fewer patients, and knew that hands hygiene after removing gloves was a control measure.
HCWs have high knowledge, positive attitudes, but low compliance concerning standard precautions. Nurses had higher knowledge, perceived risk, and appropriate HAIs' control measures than physicians and HCWs answered correctly and used appropriately control measures if have received information from educational courses and scientific journals.
PMCID: PMC2848042  PMID: 20178573
25.  Seroprevalence of Hepatitis B Virus among Health Care Workers in Korea 
We studied the seroprevalence of HBsAg, anti-HBs and anti-HBc and the vaccination histories among health care workers (HCWs) at a large suburban referral hospital in Korea. The purpose of this study was to determine the immune status of HCWs against hepatitis B virus and we also wanted to prepare a practical guideline to protect HCWs from occupational exposure. During December, 2003, 571 HCWs (56 physicians, 289 nurses, 113 technicians and 113 aid-nurses) aged between 21 and 74 yr were included in the surveillance. The positive rates of HBsAg and anti-HBs were 2.4% (14/571) and 76.9% (439/571), respectively. The positive rate of anti-HBs was lower in the physician group, and this was associated with the male gender and older age. Of the 439 anti-HBs positive cases, 320 cases (73.1%) were anti-HBc negative and this was significantly associated with a past history of HBV vaccination. The distribution of the anti-HBs levels was not associated with age (except for HCWs in their sixties), gender or occupation. Our study revealed that the seroprevalence rates of HBsAg and anti-HBs in HCWs in Korea were not different from those of the general population. Based on this surveillance, we can make reasonable decisions in case of occupational exposure to hepatitis B virus.
PMCID: PMC2733980  PMID: 16479066
Hepatitis B surface Antigens; Anti-HBs; Anti-HBc; Occupational Exposure; Health Personnel; Korea

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