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1.  Upscaling human papillomavirus vaccination in high-income countries: impact assessment based on transmission model 
Background
The decrease in human papillomavirus (HPV) vaccine prices may allow upscale already started vaccination programmes but the advantages of different options are unclear.
Methods
Using a mathematical model of HPV16 and 18 transmission and data on vaccination coverage from Italy, we compared 3 options to upscale an already started programme targeting 11-year old girls (coverage 65%): a) coverage improvement (from 65% to 90%); b) addition of 11-year-old boys (coverage 65%); or c) 1-year catch-up of older girls (coverage 50%).
Results
The reduction of cervical HPV16/18 infection as compared to no vaccination (i.e. effectiveness against HPV16/18) increased from 76% to 98% with coverage improvement in girls and to 90% with the addition of boys. With higher coverage in girls, HPV16/18 infection cumulative probability by age 35 decreased from 25% to 8% with a 38% increase in vaccine number. The addition of boys decreased the cumulative probability to 18% with a 100% increase in the number of vaccinees. For any coverage in girls, the number of vaccinees to prevent 1 woman from being infected by HPV16/18 by age 35 was 1.5, whereas it was 2.7 for the addition of boys. Catch-up of older girls only moved forward the vaccination effectiveness by 2–5 years.
Conclusions
Increasing vaccination coverage among girls is the most effective option for decreasing HPV16/18. If not achievable, vaccinating boys is justifiable if vaccine cost has at least halved, because this option would almost double the number of vaccinees.
doi:10.1186/1750-9378-9-4
PMCID: PMC3901332  PMID: 24438317
Human papillomavirus; Vaccination; High-income; Mathematical model
2.  Type-Specific Human Papillomavirus Biological Features: Validated Model-Based Estimates 
PLoS ONE  2013;8(11):e81171.
Infection with high-risk (hr) human papillomavirus (HPV) is considered the necessary cause of cervical cancer. Vaccination against HPV16 and 18 types, which are responsible of about 75% of cervical cancer worldwide, is expected to have a major global impact on cervical cancer occurrence. Valid estimates of the parameters that regulate the natural history of hrHPV infections are crucial to draw reliable projections of the impact of vaccination. We devised a mathematical model to estimate the probability of infection transmission, the rate of clearance, and the patterns of immune response following the clearance of infection of 13 hrHPV types. To test the validity of our estimates, we fitted the same transmission model to two large independent datasets from Italy and Sweden and assessed finding consistency. The two populations, both unvaccinated, differed substantially by sexual behaviour, age distribution, and study setting (screening for cervical cancer or Chlamydia trachomatis infection). Estimated transmission probability of hrHPV types (80% for HPV16, 73%-82% for HPV18, and above 50% for most other types); clearance rates decreasing as a function of time since infection; and partial protection against re-infection with the same hrHPV type (approximately 20% for HPV16 and 50% for the other types) were similar in the two countries. The model could accurately predict the HPV16 prevalence observed in Italy among women who were not infected three years before. In conclusion, our models inform on biological parameters that cannot at the moment be measured directly from any empirical data but are essential to forecast the impact of HPV vaccination programmes.
doi:10.1371/journal.pone.0081171
PMCID: PMC3882251  PMID: 24400036
3.  Vaccinating Women Previously Exposed to Human Papillomavirus: A Cost-Effectiveness Analysis of the Bivalent Vaccine 
PLoS ONE  2013;8(9):e75552.
Recent trials have indicated that women with prior exposure to Human papillomavirus (HPV) subtypes 16/18 receive protection against reinfection from the HPV vaccines. However, many of the original models investigating the cost effectiveness of different vaccination strategies for the protection of cervical cancer assumed, based on the trial results at that time, that these women received no protection. We developed a deterministic, dynamic transmission model that incorporates the vaccine-induced protection of women with prior exposure to HPV. The model was used to estimate the cost effectiveness of progressively extending a vaccination programme using the bivalent vaccine to older age groups both with and without protection of women with prior exposure. We did this under a range of assumptions on the level of natural immunity. Our modelling projections indicate that including the protection of women with prior HPV exposure can have a profound effect on the cost effectiveness of vaccinating adults. The impact of this protection is inversely related to the level of natural immunity. Our results indicate that adult vaccination strategies should potentially be reassessed, and that it is important to include the protection of non-naive women previously infected with HPV in future studies. Furthermore, they also highlight the need for a more thorough investigation of this protection.
doi:10.1371/journal.pone.0075552
PMCID: PMC3784449  PMID: 24086567
4.  High Rates of Mycobacterium tuberculosis among Socially Marginalized Immigrants in Low-Incidence Area, 1991–2010, Italy 
Emerging Infectious Diseases  2013;19(9):1437-1445.
Migration from low- and middle-income countries to high-income countries increasingly determines the severity of tuberculosis (TB) cases in the adopted country. Socially marginalized groups, about whom little is known, may account for a reservoir of TB among the immigrant populations. We investigated the rates of and risk factors for Mycobacterium tuberculosis transmission, infection, and disease in a cohort of 27,358 socially marginalized immigrants who were systematically screened (1991–2010) in an area of Italy with low TB incidence. Overall TB and latent TB infection prevalence and annual tuberculin skin testing conversion rates (i.e., incidence of new infection) were 2.7%, 34.6%, and 1.7%, respectively. Prevalence of both TB and latent TB infection and incidence of infection increased as a function of the estimated TB incidence in the immigrants’ countries of origin. Annual infection incidence decreased with time elapsed since immigration. These findings have implications for control policy and immigrant screening in countries with a low prevalence of TB.
doi:10.3201/eid1909.120200
PMCID: PMC3810899  PMID: 23965807
tuberculosis; immigrants; latent tuberculosis; Mycobacterium tuberculosis; bacteria; Italy; tuberculosis and other mycobacteria; transmission; prevalence
5.  Difference in overall and age-specific prevalence of high-risk human papillomavirus infection in Italy: evidence from NTCC trial 
BMC Infectious Diseases  2013;13:238.
Background
Although among women a decreasing prevalence of human papillomavirus (HPV) infection with increasing age has been consistently observed in high-resource countries, different age profiles have been reported elsewhere.
Methods
We compared the age profile of high-risk (HR)-HPV prevalence in nine different areas of Northern and Central Italy by studying the women recruited in the intervention arm of the New Technologies in Cervical Cancer study and tested by Hybrid Capture 2. Differences in the age-distribution of HPV infection were investigated in each centre by the joinpoint approach in a logistic model. 46,900 women aged 25 to 60 years were included in the analysis.
Results
The HR-HPV age-standardised (on Italian population) prevalence ranged from 5.7% (Trento) to 10.3% (Ravenna). HR-HPV prevalence decreased as a logistic function of increasing age in 6 of 9 centres (Trento, Verona, Florence, Bologna, Imola, and Viterbo). The effect of age on HR-HPV prevalence slopes did not differ significantly among these 6 centres, whereas significant heterogeneity in intercepts (p < 0.001) was found, reflecting different overall HR-HPV prevalence between centres. One significant joinpoint was observed in 2 centres (Padua and Ravenna), indicating that the decrease in HR-HPV prevalence by age was better described using a function composed with two logistic segments. In Padua HR-HPV prevalence decreased only slightly up to 39 years but showed a steep downturn thereafter. In Ravenna HR-HPV prevalence decreased steeply down to 45 years of age and then showed a plateau. Finally, in Turin two significant joinpoints were observed: prevalence decreased only after age 29 and showed a plateau after age 39.
Conclusions
Our results showed substantial differences in overall and age-specific HR-HPV prevalence across Italian areas. These findings may be related to different timing of changes in sexual behaviours across regions. Age-specific HR-HPV prevalence in Italy does not support an influence of age per se.
doi:10.1186/1471-2334-13-238
PMCID: PMC3669053  PMID: 23706168
Human papillomavirus; Prevalence; Age-specific
6.  Evaluation of Immigrant Tuberculosis Screening in Industrialized Countries 
Emerging Infectious Diseases  2012;18(9):1422-1429.
Improvements are needed in current screening, which is insufficient and ineffective.
In industrialized countries, tuberculosis (TB) cases are concentrated among immigrants and driven by reactivation of imported latent TB infection (LTBI). We examined mechanisms used to screen immigrants for TB and LTBI by sending an anonymous, 18-point questionnaire to 31 member countries of the Organisation for Economic Co-operation and Development. Twenty-nine (93.5%) of 31 responded; 25 (86.2%) screened immigrants for active TB. Fewer countries (16/29, 55.2%) screened for LTBI. Marked variations were observed in targeted populations for age (range <5 years of age to all age groups) and TB incidence in countries of origin of immigrants (>20 cases/100,000 population to >500 cases/100,000). LTBI screening was conducted in 11/16 countries by using the tuberculin skin test. Six countries used interferon-γ release assays, primarily to confirm positive tuberculin skin test results. Industrialized countries performed LTBI screening infrequently and policies varied widely. There is an urgent need to define the cost-effectiveness of LTBI screening strategies for immigrants.
doi:10.3201/eid1809.120128
PMCID: PMC3437731  PMID: 22931959
tuberculosis; latent tuberculosis; tuberculosis and other mycobacteria; immigration; immigrants; screening; policies; practices; industrialized countries; epidemiology
7.  Tuberculosis among Health Care Workers 
Emerging Infectious Diseases  2011;17(3):488-494.
doi:10.3201/eid1703.100947
PMCID: PMC3298382  PMID: 21392441
Tuberculosis and other mycobacteria; health care workers; systematic review; research
8.  Tuberculosis Incidence in Prisons: A Systematic Review 
PLoS Medicine  2010;7(12):e1000381.
A systematic review by Iacopo Baussano and colleagues synthesizes published research to show that improved tuberculosis (TB) control in prisons could significantly reduce the burden of TB both inside and outside prisons.
Background
Transmission of tuberculosis (TB) in prisons has been reported worldwide to be much higher than that reported for the corresponding general population.
Methods and Findings
A systematic review has been performed to assess the risk of incident latent tuberculosis infection (LTBI) and TB disease in prisons, as compared to the incidence in the corresponding local general population, and to estimate the fraction of TB in the general population attributable (PAF%) to transmission within prisons. Primary peer-reviewed studies have been searched to assess the incidence of LTBI and/or TB within prisons published until June 2010; both inmates and prison staff were considered. Studies, which were independently screened by two reviewers, were eligible for inclusion if they reported the incidence of LTBI and TB disease in prisons. Available data were collected from 23 studies out of 582 potentially relevant unique citations. Five studies from the US and one from Brazil were available to assess the incidence of LTBI in prisons, while 19 studies were available to assess the incidence of TB. The median estimated annual incidence rate ratio (IRR) for LTBI and TB were 26.4 (interquartile range [IQR]: 13.0–61.8) and 23.0 (IQR: 11.7–36.1), respectively. The median estimated fraction (PAF%) of tuberculosis in the general population attributable to the exposure in prisons for TB was 8.5% (IQR: 1.9%–17.9%) and 6.3% (IQR: 2.7%–17.2%) in high- and middle/low-income countries, respectively.
Conclusions
The very high IRR and the substantial population attributable fraction show that much better TB control in prisons could potentially protect prisoners and staff from within-prison spread of TB and would significantly reduce the national burden of TB. Future studies should measure the impact of the conditions in prisons on TB transmission and assess the population attributable risk of prison-to-community spread.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Every year, nearly 10 million people develop tuberculosis (TB)—a contagious bacterial infection usually of the lungs—and nearly two million people die from the disease. TB is caused by Mycobacterium tuberculosis, which spreads in airborne droplets when people with the disease cough or sneeze. Most people infected with M. tuberculosis never become ill—their immune system contains the infection. However, the bacteria remain dormant (latent) within the body, and a latent TB infection (LTBI) can cause active disease many years after the initial infection if host immunity declines. The symptoms of TB include a persistent cough, weight loss, and night sweats. Infection with M. tuberculosis can be diagnosed using the tuberculin skin test; tests for TB itself include chest X-rays and sputum cultures (in which bacteriologists try to grow M. tuberculosis from sputum samples, mucus brought up from the lungs by coughing). TB can usually be cured by taking several powerful antibiotics daily for several months.
Why Was This Study Done?
Last century, global control efforts began to reduce the incidence (number of new cases in a population in a given time) and prevalence (the number of affected people in a population) of LTBI and TB in many countries. Now, the emergence of antibiotic-resistant bacterial strains is thwarting these efforts. Consequently, it is important to identify settings where TB transmission is particularly high. One such setting is thought to be prisons. In these facilities, overcrowding, late case detection, inadequate treatment, and poor implementation of infection control measures (including incomplete segregation of people with active TB) might increase the TB transmission rate. However, it is not known how many people in prison become infected with M. tuberculosis or develop TB each year compared to the general population nor what percentage of LTBI and TB in the general population is attributable to exposure to M. tuberculosis in prison (the population attributable fraction or PAF%). Here, the researchers undertake a systematic review (a study that uses predefined criteria to identify all the research on a given topic) to investigate the incidence of TB in prisons.
What Did the Researchers Do and Find?
The researchers identified 23 studies that reported the incidence of LTBI and/or TB in prisons among both staff and prisoners. They estimated the incidence of TB in relevant general populations using World Health Organization data; estimates of the incidence of LTBI in the general population came from the studies themselves. The researchers then calculated the ratio between the incidence rates for LTBI and TB in prison and in the general population (incidence rate ratios or IRRs) for each study. For both LTBI and TB, the IRR varied widely between studies. The average IRR for LTBI was 26.4. That is, the average incidence of LTBI in prisons was 26.4 times higher than in the general population; the average IRR for TB was 23.0. The researchers also estimated the fraction of TB in the general population attributable to within-prison exposure to M. tuberculosis for each study. Again, there was considerable heterogeneity between the studies but, on average, the PAF% for TB in high-income countries was 8.5% (that is, one in 11 cases of TB in the general population was attributable to within-prison spread of TB); in middle-to-low–income countries, the average PAF% was 6.3%.
What Do These Findings Mean?
These findings suggest that the risk of LTBI and TB is at least an order of magnitude higher in prisons than in the general population and that the within-prison spread of LTBI and TB is likely to substantially affect the incidence of LTBI and TB in the general population. The accuracy and generalizability of these findings are limited by the small number of studies identified, by the relative paucity of studies from countries other than the USA, by study heterogeneity, and by assumptions made in the calculation of PAF%. Even so, these findings suggest that improvements in TB control in prisons would not only help to protect prisoners and staff from within-prison spread of TB but would also reduce national TB burdens. Further studies are now needed to identify the specific conditions in prisons that influence TB transmission so that rational policies can be developed to improve TB control in correctional facilities.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1000381.
This study is discussed in the December 2010 PLoS Medicine Editorial
The World Health Organization provides information on all aspects of TB, including information on TB in prisons and on the Stop TB Partnership (some information is in several languages)
The US Centers for Disease Control and Prevention has information about TB and on TB in prisons
The US National Institute of Allergy and Infectious Diseases also has detailed information on all aspects of TB
doi:10.1371/journal.pmed.1000381
PMCID: PMC3006353  PMID: 21203587
9.  Risk of tuberculin conversion among healthcare workers and the adoption of preventive measures 
Background
In industrialised countries, occupational tuberculosis among healthcare workers (HCWs) is re‐emerging as an important public health issue. To prevent and control tuberculosis transmission, several institutions have issued and implemented recommendations and practice guidelines.
Objectives
To estimate the annual rate of tuberculosis infection (ARTI; per 100 person‐years) among HCWs in Turin, the capital of the Piedmont region of Italy, to identify factors associated with variations in the ARTI and to evaluate the efficacy of the regional guidelines to prevent and control tuberculosis.
Methods
The study was conducted between 1997 and 2004 on a cohort of HCWs. The tuberculosis infection was diagnosed through tuberculin skin testing (TST) conversion and defined as an induration increase of at least 10 mm from a previous negative TST. The ARTI and the hazard ratio for each at‐risk subgroup, categorised according to working activities and settings, was estimated using exponential survival models. The efficacy of the regional guidelines was estimated by stratifying the analysis according to the moment of the implementation of the guidelines (before/after).
Results
The 2182 study participants were drawn from the dynamic cohort. The overall adjusted ARTI was 1.6 (95% CI: 1.3 to 1.9)/100 person‐years. Different workplaces (eg, administrative and infectious diseases inpatient services) and occupations (eg, clerical and medical workers) were associated with significantly different ARTIs, ranging between 0.62 and 2.62 and between 0.61 and 1.71, respectively, whereas the TST conversion risk differed by about 16–68% and 30–60%, respectively. The implementation of the guidelines coincided with overall ARTI reductions of 1.3/100 person‐years, and concurrently the variations between ARTIs of different occupations and workplaces disappeared.
Conclusions
The occupational risk categories for targeting the surveillance and prevention of tuberculosis transmission among HCWs were identified, and the introduction of preventive measures was observed to be effective in decreasing the overall risk of tuberculosis infection among HCWs.
doi:10.1136/oem.2006.028068
PMCID: PMC2092534  PMID: 16912085
10.  Variability of adenoidectomy/tonsillectomy rates among children of the Veneto Region, Italy 
Background
Despite national guidelines in 2003 aimed at limiting the recourse to tonsillectomy and/or adenoidectomy (A/T), the latter are among the most frequent pediatric surgeries performed in Italy. Aim of the study is to investigate variability of A/T rates among children of the Veneto Region, Italy.
Methods
All discharges of Veneto residents with Diagnosis-Related Groups 57–60 and ICD9-CM intervention codes 28.2 (tonsillectomy), 28.3 (adenotonsillectomy), 28.6 (adenoidectomy) were selected in the period 2000–2006 for a descriptive analysis. A multilevel Poisson regression model was applied to estimate Incidence Rate Ratios (IRR) with 95% Confidence Intervals (CI) for A/T surgery among children aged 2–9 years in 2004–2006, while taking into account clustering of interventions within the 21 Local Health Units.
Results
Through 2000–2006, the overall number of A/T surgeries decreased (-8%); there was a decline of adenoidectomies (-20%) and tonsillectomies (-8%), whereas adenotonsillectomies raised (+18%). Analyses on children aged 2–9 resulted in an overall rate of 14.4 surgeries per 1000 person-years (16.1 among males and 12.5 among females), with a wide heterogeneity across Local Health Units (range 8.1–27.6). At random intercept Poisson regression, while adjusting for sex and age, intervention rates were markedly lower among foreign than among Italian children (IRR = 0.57, CI 0.53–0.61). A/T rates in the 10–40 age group (mainly tonsillectomies) computed for each Local Health Unit and introduced in the regression model accounted for 40% of the variance at Local Health Unit level of pediatric rates (mainly adenoidectomies and adenotonsillectomies).
Conclusion
A/T rates in the Veneto Region, especially adenoidectomies among children aged 2–9 years, remain high notwithstanding a decrease through 2000–2006. A wide heterogeneity according to nationality and Local Health Units is evident. The propensity to A/T surgery of each Local Health Unit is similar in different age groups and for different surgical indications.
doi:10.1186/1472-6963-9-25
PMCID: PMC2647536  PMID: 19200396
11.  Does language matter? A case study of epidemiological and public health journals, databases and professional education in French, German and Italian 
Epidemiology and public health are usually context-specific. Journals published in different languages and countries play a role both as sources of data and as channels through which evidence is incorporated into local public health practice. Databases in these languages facilitate access to relevant journals, and professional education in these languages facilitates the growth of native expertise in epidemiology and public health. However, as English has become the lingua franca of scientific communication in the era of globalisation, many journals published in non-English languages face the difficult dilemma of either switching to English and competing internationally, or sticking to the native tongue and having a restricted circulation among a local readership. This paper discusses the historical development of epidemiology and the current scene of epidemiological and public health journals, databases and professional education in three Western European languages: French, German and Italian, and examines the dynamics and struggles they have today.
doi:10.1186/1742-7622-5-16
PMCID: PMC2570667  PMID: 18826570

Results 1-11 (11)