Purpose

Despite the ready availability of pneumococcal vaccine, vaccination rates are quite low in South Korea. This study was designed to assess perceptions and awareness about pneumococcal vaccines among subjects at risk and find strategies to increases vaccine coverage rates.

Materials and Methods

A cross sectional, community-based survey was conducted to assess perceptions about the pneumococcal vaccine at a local public health center. In a tertiary hospital, an outpatient-based pneumococcal vaccine campaign was carried out for the elderly and individuals with chronic co-morbidities from May to July of 2007.

Results

Based on the survey, only 7.6% were ever informed about pneumococcal vaccination. The coverage rates of the pneumococcal vaccine before and after the hospital campaign showed an increased annual rate from 3.39% to 5.91%. The most common reason for vaccination was "doctor's advice" (53.3%). As for the reasons for not receiving vaccination, about 75% of high risk patients were not aware of the pneumococcal vaccine, which was the most important barrier to vaccination. Negative clinician's attitude was the second most common cause of non-vaccination.

Conclusion

Annual outpatient-based campaigns early in the influenza season may improve pneumococcal vaccine coverage rates. Doctor's advice was the most important encouraging factor for vaccination.

Streptococcus pneumoniae can asymptomatically colonize the nasopharynx and cause a diverse range of illnesses. This clinical spectrum from colonization to invasive pneumococcal disease (IPD) appears to depend on the pneumococcal capsular serotype rather than the genetic background. According to a literature review, serotypes 1, 4, 5, 7F, 8, 12F, 14, 18C, and 19A are more likely to cause IPD. Although serotypes 1 and 19A are the predominant causes of invasive pneumococcal pneumonia, serotype 14 remains one of the most common etiologic agents of non-bacteremic pneumonia in adults, even after 7-valent pneumococcal conjugate vaccine (PCV7) introduction. Serotypes 1, 3, and 19A pneumococci are likely to cause empyema and hemolytic uremic syndrome. Serotype 1 pneumococcal meningitis is prevalent in the African meningitis belt, with a high fatality rate. In contrast to the capsule type, genotype is more closely associated with antibiotic resistance. CC320/271 strains expressing serotype 19A are multidrug-resistant (MDR) and prevalent worldwide in the era of PCV7. Several clones of MDR serotype 6C pneumococci emerged, and a MDR 6D clone (ST282) has been identified in Korea. Since the pneumococcal epidemiology of capsule types varies geographically and temporally, a nationwide serosurveillance system is vital to establishing appropriate vaccination strategies for each country.

Since the first reports of the A/H1N1 virus in April 2009, the pandemic influenza virus spread globally and circulated for a long time. The primary method for the control of influenza is vaccination, but levels of influenza vaccine-induced antibody are known to decline rapidly during a 6-month period. In adults aged 18 to 64 years, we compared the long-term immunogenicity of two of the influenza A/H1N1 2009 monovalent vaccines, 3.75-μg MF59-adjuvanted vaccine and 15-μg unadjuvanted vaccine. The serum hemagglutinin inhibition (HI) titers were determined prevaccination and at 1, 6, and 10 months after vaccination. One hundred six (88.3%) of the 120 subjects were monitored for the entire 10-month period after receiving the influenza A/H1N1 2009 monovalent vaccine. There were 60 patients who received the unadjuvanted vaccine and 46 patients who received the MF59-adjuvanted vaccine. The seroprotection rates, seroconversion rates, and the geometric mean titer (GMT) folds fulfilled the criteria of the European Medicines Agency (EMA) for influenza A/California/7/2009 (H1N1) at 1 month after vaccination irrespective of the vaccine composition. Although the GMTs at 1 month postvaccination were somewhat higher in the unadjuvanted vaccine recipients than in the MF59-adjuvanted vaccine recipients, the difference was not significant (P = 0.29). The seroprotection rates at 6 and 10 months postvaccination were preserved above 70% but only in the MF59-adjuvanted vaccine recipients. In conclusion, low-dose MF59-adjuvanted influenza vaccine, even with 3.75 μg hemagglutinin antigen, might induce excellent long-term immunity that is comparable to the conventional dose of unadjuvanted vaccine among healthy adults aged 18 to 64 years.

A prospective multicenter observational study was performed to investigate the epidemiology and outcomes of community-acquired severe sepsis and septic shock. Subjects included 1,192 adult patients admitted to the 22 participating intensive care units (ICUs) of 12 university hospitals in the Korean Sepsis Registry System from April, 2005 through February, 2009. Male accounted for 656 (55%) patients. Mean age was 65.0 ± 14.2 yr. Septic shock developed in 740 (62.1%) patients. Bacteremia was present in 422 (35.4%) patients. The 28-day and in-hospital mortality rates were 23.0% and 28.0%, respectively. Men were more likely to have comorbid illnesses and acute organ dysfunctions, and had higher mortality and clinical severity compared to women. While respiratory sources of sepsis were common in men, urinary sources were predominant in women. In the multivariate logistic regression analysis, cancer (odds ratio 1.89; 95% confidence interval 1.13-3.17), urinary tract infection (0.25; 0.13-0.46), APACHE II score (1.05; 1.02-1.09), SOFA score on day 1 (1.13; 1.06-1.21) and metabolic dysfunction (2.24, 1.45-3.45) were independent clinical factors for gender-related in-hospital mortality. This study provided epidemiological and clinical characteristics of community-acquired severe sepsis and septic shock in ICUs in Korea, and demonstrated the impact of clinical factors on gender difference in mortality.

Since initial reports in April 2009, the pandemic influenza A (H1N1) virus has spread globally. Influenza vaccines are the primary method for the control of influenza and its complications. We conducted a multicenter clinical trial to evaluate the immunogenicity and safety of H1N1 vaccine (Green Cross Co.) in young adults (18 to 64 years) and the elderly (≥65 years) using a two-dose regimen, with the doses administered 21 days apart. Three different regimens of hemagglutinin antigen were comparatively analyzed: 3.75 μg (MF59 adjuvanted) versus 7.5 μg (MF59 adjuvanted) versus 15 μg (nonadjuvanted) in young adults and 3.75 μg (MF59 adjuvanted) versus 7.5 μg (MF59 adjuvanted) in the elderly. In young adults, all three vaccine regimens met the European Agency for the Evaluation of Medicinal Products (EMA) criteria after the first dose. In the elderly, on day 21 after the first dose, the rates of seroprotection and seroconversion were significantly higher for the 7.5-μg dose of MF59 adjuvanted vaccine than for the 3.75-μg dose (58.0% versus 44.3% [P = 0.03] and 53.7% versus 37.2% [P < 0.01], respectively). After the second dose, the geometric mean titer (GMT) increment was blunted with a 15-μg dose of nonadjuvanted vaccine, whereas the GMT increased about 2-fold with MF59 adjuvanted vaccines. In conclusion, a single 7.5-μg dose of MF59 adjuvanted vaccine would have a practical advantage over a two-dose, 3.75-μg, MF59 adjuvanted vaccine priming schedule. Following a two-dose priming schedule, the increase in hemagglutinin inhibition titers was higher with MF59 adjuvanted vaccine than with nonadjuvanted vaccine.

Though the 2009 worldwide influenza A (H1N1) pandemic has been declared to have ended, the influenza virus is expected to continue to circulate from some years as a seasonal influenza. A rapid antigen test (RAT) can aid in rapid diagnosis and allow for early antiviral treatment. We evaluated the clinical usefulness of RAT using SD Bioline Influenza Antigen Test® kit to detect the influenza virus, considering various factors. From August 1, 2009 to October 10, 2009, a total of 938 patients who visited the outpatient clinic at Korea University Guro Hospital with influenza-like illnesses were enrolled in the study. Throat or nasopharyngeal swab specimens were obtained from each of the patients. Using these specimens, we evaluated the influenza detection rate by rapid antigen test based on the real-time reverse-transcriptase polymerase chain reaction (rRT-PCR) method. In comparison with rRT-PCR, the sensitivity and specificity of the RAT were 44.0% and 99.9%, respectively. The cyclic threshold values of RAT negative specimens were higher than RAT positive specimens (30.1±3.1 vs. 28.3±3.9, p=0.031). The sensitivity of the RAT kit was higher in patients who visited clinics within two days of symptom onset (60.4% vs. 11.1%, p=0.026). The results of this study show that the RAT cannot be recommended for general use in all patients with influenza-like illness because of its low sensitivity. The RAT may be used, only in the settings with limited diagnostic resources, for patients who visit a clinic within two days of symptom onset.

Influenza vaccines are the primary method for controlling influenza and its complications. This study was conducted as a phase 3, randomized, double-blind, controlled, multi-center trial at seven university hospitals to evaluate the immunogenicity and safety of an inactivated, split, trivalent influenza vaccine (GC501, Green Cross Corporation, Yongin, Korea), which was newly manufactured in Korea in 2008. Between September 21 and 26, a total of 329 healthy subjects were recruited for the immunogenicity analysis, while 976 subjects were enrolled for the safety analysis. The GC501 vaccine met both FDA and EMEA criteria with ≥ 80% of subjects achieving post-vaccination titers ≥ 40 for all three subtypes, even in the elderly. The vaccine was well tolerated with only mild systemic and local adverse events. In summary, GC501 showed excellent immunogenicity and a good safety profile in both young adults and the elderly. The licensure of GC501 might be an important basis in preparation for the future influenza pandemic.

Lactococcus lactis cremoris infections are very rare in humans. We experienced liver abscess and empyema due to L. lactis cremoris in an immunocompetent adult. A 42-yr-old man was admitted with fever and abdominal pain. Abdominal computed tomography (CT) revealed a liver abscess and chest CT showed loculated pleural effusion consistent with empyema. L. lactis cremoris was isolated from culture of the abscess material and blood. The patient was treated with pus drainage from liver abscess, video-assisted thoracoscopic decortications for empyema, and antibiotics including cefotaxime and levofloxacin. The patient was completely recovered with the treatment. To our knowledge, this is the first report of a L. lactis cremoris infection in Korea.

Non-typhoidal Salmonella (NTS) is an important commensal microorganism. The purpose of this study was to determine the epidemiological relation between NTS isolates from livestock and NTS isolates from human by analyzing antimicrobial susceptibilities and performing molecular typing. We determined the serotypes of 36 human clinical isolates and 64 livestock isolates, performed antimicrobial susceptibility testing against 8 antibiotics, and determined the molecular types of isolated NTS spp. by pulsed field gel electrophoresis (PFGE). In human isolates, S. enteritidis was the most common serotype (17 isolates; 47.2%) and S. typhimurium the second most (8 isolates; 22.2%). In livestock isolates, S. typhimurium was the most common serotype (15 isolates; 23.44%), and S. enteritidis was the second most (14 isolates; 21.88%). Ampicillin and tetracycline resistance were 50% (32/64 isolates) each among broiler-chicken NTS isolates. No human or livestock NTS isolates showed resistance to ciprofloxacin, TMP-SMX, or ceftriaxone. However, 19.4% (7/36) and 46.8% (30/64) of the human and livestock NTS isolates were resistant to nalidixic acid (MIC ≥16 mg/mL), respectively. The presence of the three identical PFGE molecular types from human and broiler-chicken NTS isolates suggests the possibility of transmission from livestock to humans.

Background

Disseminated mycobacterium avium complex (MAC) occurs mainly in immunocompromised hosts, which is associated with abnormal cellular immunity.

Case presentation

A 26-year-old pregnant woman presented with fever and general weakness. Miliary lung nodules were noted on chest X-ray. Under the impression of miliary tuberculosis, anti-tuberculosis medication was administered. However, the patient was not improved. Further work-up demonstrated MAC in the sputum and placenta. The patient was treated successfully with clarithromycin-based combination regimen.

Conclusion

This appears to be the first case of disseminated MAC in an otherwise healthy pregnant woman. Clinicians should be alert for the diagnosis of MAC infection in diverse clinical conditions.

Spontaneous bacterial peritonitis (SBP) is an ascitic fluid infection as a complication of end stage liver disease. The outcome is related to the severity of hepatorenal function, gastrointestinal bleeding, and many others; however it is not well known whether the infection acquisition sites have an effect on the prognosis of SBP. In order to identify the prognostic significance of the acquisition sites, we studied 106 patients who were diagnosed as culture positive SBP between October 1998 and August 2003. Thirty-two episodes were nosocomial and 74 were community acquired. Gram-negative bacilli such as Escherichia coli were dominant in both of the nosocomial and community-acquired SBPs. Despite significantly higher resistance to cefotaxime in nosocomial isolates compared to community-acquired isolates (77.8% vs. 13.6%, p=0.001), no difference was found regarding short or long term prognosis. Infection acquisition sites were not related to short or long term prognosis either. Shock, gastrointestinal bleeding and renal dysfunction were related to short term prognosis. Only Child-Pugh class C was identified as an independent prognostic factor of long-term survival.

We conducted an epidemiologic study to understand temporal and spatial patterns of hemorrhagic fever with renal syndrome (HFRS) in the Republic of Korea (ROK). We estimated the incidence among civilians in endemic areas through the active surveillance system during the major epidemic periods, from September to December, between 1996 and 1998. We also estimated the prevalence among Korean military personnel from 1995 to 1998. In addition, we assessed seroprevalence, subclinical infection rate, and vaccination rates in both civilians and military personnel. The incidence in civilians ranged from 2.1 to 6.6 per 100,000 person-months. The annual prevalence in the military personnel was 40-64 per 100,000 military populations, and remained generally constant throughout the study period with seasonal variation. This is the prospective epidemiologic data set on HFRS in the ROK since the inactivated Hantaan virus vaccine was licensed for use in the late 1990s. These results will be invaluable in establishing a national immunization program against HFRS.

Background

Despite the increasing popularity of acupuncture, the importance of infection control is not adequately emphasized in Oriental medicine. In December 2001, an Oriental medical doctor in Seoul, South Korea, encountered several patients with persistent, culture-negative skin lesions on the trunk and extremities at the sites of prior acupuncture treatment. We identified and investigated an outbreak of Mycobacterium abscessus cutaneous infection among the patients who attended this Oriental medicine clinic.

Methods

Patients were defined as clinic patients with persistent cutaneous infections at the acupuncture sites. Medical records for the previous 7 months were reviewed. Clinical specimens were obtained from the patients and an environmental investigation was performed. M. abscessus isolates, cultured from patients, were compared by pulsed-field gel electrophoresis (PFGE).

Results

Forty patients who attended the Oriental medicine clinic and experienced persistent cutaneous wound infections were identified. Cultures from five of these patients proved positive, and all other diagnoses were based on clinical and histopathologic examinations. All environmental objects tested were negative for M. abscessus, however, most were contaminated by various nosocomial pathogens. Molecular analysis using PFGE found all wound isolates to be identical.

Conclusion

We have identified a large outbreak of rapidly growing mycobacterial infection among patients who received acupuncture at a single Oriental medicine clinic. Physicians should suspect mycobacterial infections in patients with persistent cutaneous infections following acupuncture, and infection control education including hygienic practice, should be emphasized for Oriental medical doctors practicing acupuncture.