Incidence Of Acute Hepatitis Research Articles

Molecular and epidemiological characteristics of hepatitis B virus in conditions of mass vaccine prophylaxis

The urgency of the problem of hepatitis B is due to the significant economic damage, medical, social and epidemiological significance of this disease, the ubiquity, severity, high frequency of adverse outcomes of infection, active involvement in the epidemic process of persons of reproductive and working age. The socio-economic significance of hepatitis B is evidenced by the morbidity, prevalence and mortality from this infection. The decrease in the incidence of acute hepatitis B, which is observed in Russia at the present time, is not a reason for an optimistic view of the problem, since the incidence of chronic hepatitis B over the past five years is almost at the same level (9–10 cases per 100 000 population). To date, laboratory diagnosis of viral hepatitis is based on the determination of specific markers by enzyme immunoassay. The use of molecular genetic methods opens up new prospects in the study of infection, allows us to identify patterns of manifestation, mechanisms of regulation of the epidemic process, including the study of the variability of the pathogen in space and time. The use of molecular genetic research methods should be considered not as an alternative, but as a mandatory addition to the regulated diagnostic schemes, which will effectively identify the pathogens of viral hepatitis, assess the identity of viral isolates and on this basis improve epidemiological surveillance and control of these infections.

Incidence of acute hepatitis B in a metropolitan area: a follow-up study after increased genotype A infection

Incidence of acute hepatitis B in a metropolitan area: a follow-up study after increased genotype A infection

Data analysis on hepatitis B through pilot surveillance reporting system in Henan province, 2012-2016

Objective: To standardize the reporting system on hepatitis B in order to improve the quality of monitoring program in Henan province. Methods: A total of 6 sites of Hepatitis B pilot surveillance were selected in Xinzheng of Zhengzhou city, Linzhou of Anyang city, Shanyang district of Jiaozuo city, Shaoling district of Luohe city, Yongcheng of Shangqiu city, Pingqiao district of Xinyang city in Henan province. Subjects under study were those reported hepatitis B cases, from 2012 to 2016. Cases diagnosed in 2011 were chosen as controls. Data on classification of hepatitis B, time that HBsAg became positive and ALT value of the cases were analyzed annually. 5 ml venous blood was collected and anti-HBc IgM confirmed test was made for those suspected acute cases on hepatitis B. Based on the 2016 data from the monitoring system, the incidence of acute hepatitis B in Henan province was estimated. Results: The number of reported hepatitis B cases had declined in 6 sites of Hepatitis B pilot surveillance substantially. A total of 17 436 hepatitis B reported in 2011 but only 2 632 cases were reported in 2016, with a reduction of 84.90%(14 804/17 436) in these six monitoring sites. The number of unclassified hepatitis B cases also dropped sharply. In 2011, 36.87% of the cases were unclassified, but the figure reduced to 0.08% in 2016, from the six sites. The rate on ALT detection also gradually improved. The rate of misdiagnosis on HBV carrier from hepatitis B almost disappeared. From 2013 to 2016, 777 blood samples were collected from six pilot sites. 29.34% (228/777) of the blood samples were tested positive for anti-HBc IgM after confirmed by the hepatitis laboratory of the China Center for Disease Control and Prevention. Conclusions: Since the development of the pilot surveillance program, the quality of reporting system on hepatitis B had been improved, as well as the accuracy of diagnosis. Rate on the accuracy of reporting on hepatitis B and the methods of testing should be improved at the monitoring sites.

Seroprevalence and disease burden of acute hepatitis A in adult population in South Korea.

BackgroundAdult seroprevalence of HAV is decreasing in developed countries including South Korea, due to general sanitation improvement. Although hepatitis A vaccination was introduced in South Korea more than 20 years ago, recent infection rates have not decreased. In this study, we investigate the seroprevalence of anti-HAV IgG, and estimate the national disease burden of acute hepatitis A in adult population.MethodsSeroprevalence data were collected from health promotion center of Korea University Guro Hospital, in Seoul, Korea from 2010 to 2014. Data from adults (≥20-years) being tested for anti-HAV IgG were included. In addition, epidemiological and clinical data of patients diagnosed with acute hepatitis A from 2009 to 2013, were collected from Korean Statistical Information Service (KOSIS) and the National Health Insurance Service (NHIS) database. Data were stratified and compared by age groups.ResultsA total of 11,177 subjects were tested for anti-HAV IgG from 2010 to 2014. Age-related seroprevalence showed relatively low seropositivity in young adults. Incidence of acute hepatitis A was highest in 2009 and lowest in 2013. When categorized by age group, adults in their 20s and 30s had more HAV infections and related-admissions than older adults. However, ICU admission rate and average insurance-covered cost was high in older adults.ConclusionThe anti-HAV IgG seropositivity in Korean younger adult population was low while the incidence of acute hepatitis A was high, especially in the 20–39 aged. However, a substantial number of older adults were infected, and required more intensive procedures and incurred higher insurance-covered medical costs.

Incidence of acute hepatitis A among HIV-positive patients during an outbreak among MSM in Taiwan: Impact of HAV vaccination.

An unprecedented outbreak of acute hepatitis A has occurred among MSM in Taiwan since June 2015. We aimed to describe the seroepidemiology of HAV infection and to investigate the relationship between HAV vaccination and the incidence of acute hepatitis A among HIV-positive patients at the largest designated hospital for HIV care during the outbreak. Between 2012 and 2016, the HAV serostatus, vaccination history and clinical characteristics of HIV-positive patients were retrospectively reviewed. A case-control study was performed to identify the factors associated with acute hepatitis A. The trends of HAV vaccination rate and incidence of acute hepatitis A among HAV-seronegative patients were examined during the outbreak. During the 4.5-year period, 2088 HIV-positive patients with a mean age of 37.7years and 90.2% being MSM were included. The overall HAV seroprevalence was 34.3%, which was significantly higher in older and non-MSM patients. The estimated incidence rate of acute hepatitis A was 52.6 cases per 1000 person-years of follow-up during the outbreak. The associated factors with acquiring acute hepatitis A were recent syphilis and having not received HAV vaccines. The HAV vaccination rate during the outbreak increased from 4.7% to 70.6% and the incidence rate of acute hepatitis A declined when up to 65% of the patients were immunized or tested positive for HAV. The seroprevalence of HAV infection was low in the younger HIV-positive individuals. Prevention of acute hepatitis A was achieved among HIV-positive, HAV-seronegative patients through HAV vaccination and increased herd immunity during the ongoing outbreak.

The Dynamics of Incidence of Chronic Hepatitis B and C in the Population of Almaty city for 2001-2014

The results of a retrospective epidemiological analysis revealed a sharp decline in the incidence of acute hepatitis B among the entire population of Almaty and the absence of acute hepatitis B, acute hepatitis C and chronic hepatitis C among children under 14 years of age. We found an increased incidence of chronic hepatitis B and chronic hepatitis C among the population of Almaty. Assessment of the hepatitis C incidence by the cumulative indices more objectively reflects the epidemiological situation for this disease. Int J Biomed. 2016;6(3):222-224.).

HEPATITIS B INFECTION IN EASTERN REGIONS OF BULGARIA

Background: Bulgaria is a country of moderate endemicity for hepatitis B infection with 3-7% of the general population chronically infected with the virus. Since 1991, an obligatory vaccination has been implemented for all healthy newborns. As a result, twenty years later, hepatitis B prevalence is significantly reduced but viral hepatitides still represent an important public health problem that needs to be addressed especially in some ethno-religious and regional groups. Purpose: No recent published data are available about hepatitis B circulation in Bulgaria and in its Eastern part particularly. In the current study, we analyze the epidemiological data on hepatitis B cases in easternmost Bulgarian regions and try to determine the possible risk, which the infection poses to public health in these regions. Material/Methods: We performed a retrospective analysis (2008-2014) using epidemiological data from the National surveillance system for hepatitis B notification. Results: The incidence of acute hepatitis B in all considered regions has been durably decreasing for the last seven years: while in 2014 its total value was 9,69%000, in 2014 it reached a minimal rate of 3,09%000. We found that young individuals in their 20s years (the borderline generation before and after implementation of mandatory vaccination) are most vulnerable to hepatitis B. South regions are also more affected by hepatitis B infection when compared with regions on the North. Conclusions: We reported a stable downward trend in the incidence of hepatitis B infection in all studied regions of Bulgaria. This result can be directly linked with the presence of effective vaccination program at national level.

Viral Hepatitis Vaccination Status for Patients on the Liver Transplant Waiting List

Introduction: The incidence of acute hepatitis A or acute or chronic hepatitis B after a liver transplant is rare but can be associated with graft dysfunction or loss. Additionally, with the use of extended criteria donor organs, the presence of a hepatitis B surface antibody allows the recipient the option to receive a hepatitis B-core positive graft. Hepatitis A and B vaccination in liver transplant recipients results in lower rates of antibody formation than in the pretransplant setting. Current AASLD guidelines recommend that all nonimmune liver transplant candidates should receive hepatitis A and B vaccines.Little information is available about the consistent implementation of these recommendations.Our aim was to determine current hepatitis A(HAV) and hepatitis B(HBV) immunity rates for patients on the liver transplant list at a tertiary care center and any associations with unsuccessful vaccinations. Methods: A retrospective chart review was performed of adult patients listed for liver transplantation at a single transplant center as of June 2014.Data collected includes demographics, etiology of cirrhosis, HAV/HBV immune status and vaccination history. To determine immune status, we looked at the presence of serological markers (HBsAg, anti-HBc, anti-HBs, IgG-anti-HAV).Statistical analysis was performed using the student t-test and the Chi-square test to detect any association between immune status and unsuccessful vaccination with patients' demographic data and etiology of cirrhosis. Results: A total of 184 patients (73 females, 111 males) were on the liver transplant list as of June 2014. Mean age was 58. Etiology varied with 35% due to hepatitis C and 18% due to alcohol. 119 (66%) patients were immune to HAV. Of this,15 (13%) had been previously vaccinated with the remaining 104 (87%) developing immunity through prior infection. 48 (27%) patients demonstrated immunity to HBV. Of these, 17 (36%) had evidence of previously cleared infection and the remaining 31 (67%) were vaccinated. 12 patients vaccinated for HBV either never acquired immunity or lost protective antibody over time.There was no statistically significant association between etiology of liver disease and unsuccessful vaccination for HAV (0.500) and HBV (0.517).There was no significant association between HAV immune status and age (0.898), sex (0.918) and etiology of liver disease (0.506).There was also no significant correlation between HBV immune status and age (0.071), sex (0.686) and etiology of liver disease (0.052). Conclusion: The presence of protective antibody for HAV or HBV among patients on the liver transplant waiting list is low, particularly for HBV. This is despite current AASLD recommendations for vaccination of nonimmune patients in the pre-transplant setting. We next hope to identify potential barriers to vaccination and improve immunity rates prior to transplant

Rapid molecular testing for Norovirus by the Xpert® Norovirus Assay improves management of nosocomial epidemics in a geriatric hospital setting

s / Journal of Clinical Virology 70 (2015) S1–S126 S97 Results: The patient demographic ranged from 1 to 75 years (Mean: 45.3 years, SD:14.8) with a female to male ratio of 1:1.18. HEV IgM was detected in 0.37% and 2.7% of samples by Mikrogen and Wantai respectively. HEV IgG, was detected in 5.4% and 9.0% of samples by Mikrogen and Wantai respectively. Two acute cases were identified, one samplewas reactive for bothHEV IgMandHEV IgG but was not found to be viraemic; the second sample was IgM reactive and HEV RNA positive. Three IgG positive samples were also found to be viraemic with genotype 3 by RT-PCR. Conclusions:Asperourdefinition, therewere twocasesof acute hepatitis E in our archived panel 2008–2009, one of which was not viraemic. The seroprevalence of HEV IgG ranged from 5.4 to 9.0% with the two assays. Differences in the HEV IgG results between assays are known to occur and molecular testing has been recommended for patients who may be immune-suppressed. These results would also suggest that molecular testingmay preferential. We hence conclude that the increase in the incidence of acute hepatitis E seen over the past few years in Scotland is real and not an artifact of improved diagnostics. http://dx.doi.org/10.1016/j.jcv.2015.07.224

Hepatitis B virus burden in developing countries

Hepatitis B virus (HBV) infection has shown an intermediate or high endemicity level in low-income countries over the last five decades. In recent years, however, the incidence of acute hepatitis B and the prevalence of hepatitis B surface antigen chronic carriers have decreased in several countries because of the HBV universal vaccination programs started in the nineties. Some countries, however, are still unable to implement these programs, particularly in their hyperendemic rural areas. The diffusion of HBV infection is still wide in several low-income countries where the prevention, management and treatment of HBV infection are a heavy burden for the governments and healthcare authorities. Of note, the information on the HBV epidemiology is scanty in numerous eastern European and Latin-American countries. The studies on molecular epidemiology performed in some countries provide an important contribution for a more comprehensive knowledge of HBV epidemiology, and phylogenetic studies provide information on the impact of recent and older migratory flows.

Viral hepatitis in Denmark

OZET To provide an overview of the epidemiology and public health strategies concerning viral hepatitis in Denmark. Studies and guidelines in viral hepatitis in Denmark and national surveillance data were reviewed. The incidence of acute hepatitis A has declined since 1980 and was 0.2/105 in 2011. The majority of cases are imported by children of foreign origin. The incidence of acute hepatitis B has also been declining; the prevalence of chronic hepatitis B is estimated to be 0.24% of the adult population and genotype D is the most prevalent. The majority of patients with chronic hepatitis B are immigrants from high incidence regions and co-infection with hepatitis D is rare. The prevalence of hepatitis C is 0.38% of the adult population and the majority has been infected through 4 drug use. Genotype 1 is the most prevalent genotype. Hepatitis E is a rare and imported condition but a high prevalence of anti-HEV among farmers indicates the infection is an asymptomatic zoonotic infection in Denmark. There are national treatment guidelines for hepatitis B and C and the treatment is provided free of charge to all Danish residents. Vaccination against hepatitis A is recommended to persons travelling to high incidence countries and persons with chronic hepatitis C. Vaccination against hepatitis B is recommended and free of charge to all newborns of HBsAg positive mothers and persons specifically assessed to be at an increased risk. Denmark is a low incidence country for viral hepatitis, but continuous attention is required within risk groups. (Viral Hepatitis Journal 2014; 20(2): 43-48)

Low prevalence of hepatitis C infection among HIV-infected individuals in Slovenia: a nationwide study, 1985–2013

After introduction of highly active antiretroviral therapy and consecutive successful control of HIV infection hepatitis C virus (HCV) has become an important pathogen in HIV infected patients. HIV infection in a person who is also HCV infected results in reduced rate of spontaneous HCV RNA clearance, faster liver disease progression and more aggressive course of liver disease. A total of 639 individuals were cumulatively reported as HIV-infected in Slovenia until the end of 2013. The majority of HIV-infected were men (553/639; 86.5%) and among them 68.2% were men who have sex with men. The predominant HIV-1 subtype in Slovenia is subtype B, which is present in 85.8% of the infected individuals. We tested 575 (90.0%) of 639 Slovenian individuals who were confirmed as HIV positive by the end of 2013 for HCV infection. All individuals included in a study were tested for both anti-HCV and HCV RNA. Out of 575 HIV-infected individuals 44 (7.6%) had anti-HCV specific antibodies, and 32 of them (72.7%) were also HCV RNA positive. We didn’t detect HCV RNA alone in any of the 531 anti-HCV-negative individuals. Anti-HCV positivity was significantly more frequent in HIV-infected individuals who acquired HIV by parenteral route (73.3%) comparing with those who acquired HIV by sexual route (2.6%). The most prevalent HCV genotype among HIV-infected individuals was genotype 1 (70.8%), followed by genotype 3 (16.7%), genotype 4 (8.3%) and genotype 2 (4.2%). HCV genotypes distribution didn’t significantly differ between HIV-positive and HIV-negative, HCV-positive Slovenian patients. Our study which was performed on the highest proportion per entire population of HIV-infected individuals from a certain country identified Slovenia as the country with the lowest prevalence of HCV infection among HIV-infected individuals. The predominance of sexual transmission of HIV (79.2%) in Slovenia and the fact that HIV has not yet entered the intravenous drug users’ community in Slovenia are the two most likely reasons for low prevalence of HIV-HCV co-infection. However, the present epidemiological situation in Slovenia needs to be monitored closely since it could quickly change in a case of an increase in the incidence of acute hepatitis C among HIV-infected men who have sex with men and/or increase of HIV infection among intravenous drug users in the country, as it happened recently in some neighboring countries.

Prevalence and outcomes of acute hepatitis B in Okayama, Japan, 2006-2010.

Hepatitis B virus (HBV) is one of the major viruses causing acute hepatitis. Recently, the incidence of acute hepatitis with genotype A has been increasing in Japan. The aim of this study was to investigate acute hepatitis B (AHB) in Okayama prefecture, with special attention to HBV genotype A. AHB patients who visited one of 12 general hospitals in Okayama prefecture between 2006 and 2010 were retrospectively analyzed. Over the course of the study period, 128 patients were diagnosed with AHB. Sexual transmission was supposed in the majority of patients (78 patients, 61%), including 59 (76%) having sex with heterosexual partners. The genotypes of HBV were assessed in 90 patients (70%), of whom 27 patients were infected with genotype A, 5 with genotype B, and 58 with genotype C. The prevalence of genotype A was significantly higher among male patients (28.7%), aged 20-29 (35.6%, p＜0.01), among men who had sex with men (100%, p＜0.005), and among patients having sex with unspecified partners (44.8%, p＜0.005). Genotype A was not a significant factor associated with delayed HBsAg disappearance. Caution should be exercised with regard to sexually transmissible diseases in order to slow the pandemic spread of AHB due to genotype A.

Acute Hepatitis B in an Urban Tertiary Care Hospital in the United States

The incidence of acute hepatitis B virus (HBV) infection in the United States is declining, and precise epidemiology for newly acquired infection remains obscure. We sought to clarify the clinical presentation and management of acute symptomatic HBV infection at a hepatology referral center. We prospectively evaluated the demographic, epidemiological, clinical, and treatment data of 32 patients with acute symptomatic HBV who were referred to a single urban tertiary care hospital in the United States. Slightly more than half of the patients were male (53%) or belonged to the black race (53%) and slightly fewer than half of the patients (47%) were unemployed. The median patient age was 41.9 years, and 20 (63%) patients were unmarried. The most common HBV risk factor was a new sexual partner over the previous months (34%). Fifteen percent of the patients reported no known risk factors. Four (13%) patients were diabetic. Presenting symptoms included jaundice (75%), abdominal pain (63%), and marked fatigue (59%). The mean peak for aspartate aminotransferase/alanine aminotransferase was 1822/2109 IU/L, for total bilirubin was 12.6 mg/dL, and for International Normalized Ratio was 1.53. Eight patients (25%) were started on oral nucleot(s)ide therapy. One diabetic patient underwent liver transplantation. In a sample of patients from a US urban tertiary hepatology center, common epidemiological features of acute symptomatic hepatitis B were being middle aged and unmarried and having acquired the infection through a new sexual contact. Antiviral therapy was sometimes but not commonly started. These data reinforce the need for HBV vaccination of individuals at risk, including those not traditionally targeted.

Hospital-Based Surveillance for Viral Hemorrhagic Fevers and Hepatitides in Ghana

BackgroundViral hemorrhagic fevers (VHF) are acute diseases associated with bleeding, organ failure, and shock. VHF may hardly be distinguished clinically from other diseases in the African hospital, including viral hepatitis. This study was conducted to determine if VHF and viral hepatitis contribute to hospital morbidity in the Central and Northern parts of Ghana.Methodology/Principal FindingsFrom 2009 to 2011, blood samples of 258 patients with VHF symptoms were collected at 18 hospitals in Ashanti, Brong-Ahafo, Northern, Upper West, and Upper East regions. Patients were tested by PCR for Lassa, Rift Valley, Crimean-Congo, Ebola/Marburg, and yellow fever viruses; hepatitis A (HAV), B (HBV), C (HCV), and E (HEV) viruses; and by ELISA for serological hepatitis markers. None of the patients tested positive for VHF. However, 21 (8.1%) showed anti-HBc IgM plus HBV DNA and/or HBsAg; 37 (14%) showed HBsAg and HBV DNA without anti-HBc IgM; 26 (10%) showed anti-HAV IgM and/or HAV RNA; and 20 (7.8%) were HCV RNA-positive. None was positive for HEV RNA or anti-HEV IgM plus IgG. Viral genotypes were determined as HAV-IB, HBV-A and E, and HCV-1, 2, and 4.Conclusions/SignificanceVHFs do not cause significant hospital morbidity in the study area. However, the incidence of acute hepatitis A and B, and hepatitis B and C with active virus replication is high. These infections may mimic VHF and need to be considered if VHF is suspected. The data may help decision makers to allocate resources and focus surveillance systems on the diseases of relevance in Ghana.

Targeted vaccination programme successful in reducing acute hepatitis B in men having sex with men in Amsterdam, The Netherlands

In the Netherlands, transmission of hepatitis B virus occurs mainly within behavioural high-risk groups, such as in men who have sex with men. Therefore, a vaccination programme has targeted these high-risk groups. This study evaluates the impact of the vaccination programme targeting Amsterdam's large population of men who have sex with men from 1998 through 2011. We used Amsterdam data from the national database of the vaccination programme for high-risk groups (January 1, 1998 to December 31, 2011). Programme and vaccination coverage were estimated with population statistics. Incidence of acute hepatitis B was analyzed with notification data from the Amsterdam Public Health Service (1992-2011). Mathematical modelling accounting for vaccination data and trends in sexual risk behaviour was used to explore the impact of the programme. At the end of 2011, programme coverage was estimated at 41% and vaccination coverage from 30% to 38%. Most participants (67%) were recruited from the outpatient department for sexually transmitted infections and outreach locations such as saunas and gay bars. Incidence of acute hepatitis B dropped sharply after 2005. The mathematical model in which those who engage most in high-risk sex are vaccinated, best explained the decline in incidence. Transmission of hepatitis B virus among Amsterdam's men who have sex with men has decreased, despite ongoing high-risk sexual behaviour. Vaccination programmes targeting men who have sex with men do not require full coverage; they may be effective when those who engage most in high-risk sex are reached.

Study on the etiology of acute hepatitis hospitalized patients in Beijing Ditan Hospital from 2002 to 2011

To explore the etiology of acute hepatitis hospitalized patients in Beijing Ditan Hospital from 2002 to 2011. We summed up the changes in the characteristics of the etiology of acute hepatitis of patients mentioned above, and preliminarily analyze the causes. From 2002 to 2011, 6235 patients with acute hepatitis were admitted to Ditan Hospital, aged between 12 and 78 years old, Of which 4309 were male and 1926 female. Acute viral hepatitis accounted for 70.44%-85.07%, while CMV, EBV, drug-induced liver injury accounted less than 5%, and acute hepatitis D and acute hepatitis C less than 1.10%. From year to year, the incidence and constitution of acute hepatitis changed significantly. The proportion of patients with acute hepatitis in total hospitalized patients was from 20. 38% to 2.05%. In 10 years, the percentage of acute hepatitis A decreased most obviously, about 99.11%, while 45.07% decline in incidence of acute hepatitis B and 62. 28% of acute hepatitis E. The constituent ratio of acute hepatitis also changed significantly. The proportion of acute hepatitis A declined from 31.31% in 2002, to less than 1% in 2011. The proportion of acute hepatitis B increased from 26.47% in 2002 to 45.88% in 2011, an increase of about 2 folds in 10 years. The proportion of acute hepatitis E increased from 26.73% in 2002 to 32.05% in 2010, a rise of 1.20 times in 10 years. The proportion of patients with acute hepatitis in total hospitalized patients decreased from 20. 38% in 2002 to 2. 05% in 2011 in Beijing Ditan Hospital. The constituent ratio of acute hepatitis changed, too.

When ‘raw sex’ turns to a ‘raw deal’ … taking the opportunity to think about sex? Interviews with HIV-positive gay men diagnosed with acute hepatitis C

Since 2001, cases of hepatitis C virus (HCV) sexual transmission have been reported in France, among HIV-positive gay men who do not inject drugs. An earlier study focused on the incidence of acute hepatitis C and risk factors associated with HCV transmission. The present study, based on in-depth interviews, aimed to highlight the biography, the sexual practices and the experiences of gay men infected with HCV. Beyond an apparent uniformity, the group of interviewees illustrates a variety of situations, life stories and health pathways, depending on their age. These well-adjusted gay men were used to engaging in unprotected sexual practices, but before their diagnosis they largely ignored HCV-transmission risk, which was associated in their mind with a pejorative drug addict image. Once diagnosed with acute hepatitis C, they experienced a critical and emotional period during which they were open to discuss their sexual practices and reconsider risk-reduction procedures, without being willing to give up on their satisfying sex life. Health educators should consider labelling hepatitis C as an STI in order to disrupt its negative image and to help HIV-positive gay man raise their awareness of HCV-transmission risks and implement better risk-reduction strategies.

P3.420 Targeted Vaccination Programme Successful in Reducing Acute Hepatitis B in Men Having Sex with Men in Amsterdam, the Netherlands

Background In the Netherlands, transmission of hepatitis B virus occurs mainly within behavioural high-risk groups, such as in men who have sex with men. Therefore, a vaccination programme has targeted these high-risk groups. Previous evaluations of this programme up until 2006 (incidence trend analysis, mathematical modelling and molecular sequence models) could prove no impact. This study evaluates the impact of the vaccination programme targeting Amsterdam’s large population of men who have sex with men from 1998 through 2011. Methods We used Amsterdam data from the national database of the vaccination programme for high-risk groups (January 1, 1998 to December 31, 2011). Programme and vaccination coverage were estimated with population statistics. Incidence of acute hepatitis B was analysed with notification data from the Amsterdam Public Health Service (1992 to 2011). Mathematical modelling accounting for vaccination data and trends in sexual risk behaviour was used to explore the impact of the programme. Results At the end of 2011, programme coverage was estimated at 41% and vaccination coverage 30% to 38%. Most participants (67%) were recruited from the outpatient department for sexually transmitted infections and outreach locations such as saunas and gay bars. Incidence of acute hepatitis B dropped sharply after 2005. The mathematical model in which those who engage most in high-risk sex are vaccinated, best explained the decline in incidence. Conclusions Transmission of hepatitis B virus among Amsterdam’s men who have sex with men has decreased, despite ongoing high-risk sexual behaviour. International concern also exists about the effectiveness of such programmes when the uptake or coverage remains low. This study proves that a targeted vaccination programme can be effective with vaccination coverage below 40%, as long as MSM who engage most in high-risk sex, such as clients of STI clinics, are reached.

Estimación de la incidencia de la hepatitis B en Cataluña mediante modelos aditivos generalizados y su relación con las tasas de inmigración y vacunación

IntroductionThis study investigates the relationship between the reduction in the incidence of acute hepatitis B and the universal vaccination programme of preadolescents in Catalonia, taking population changes into account. MethodsA descriptive analysis was made of the reported incidence of hepatitis B according to geographical area (county), year (1992-2010), age (in age groups), sex, vaccination coverage, and the percentage of immigration. Generalized additive models (GAM) were used as they can be adapted flexibly to different causal reasons for the evolution of transmittable diseases. The incidence rate was calculated as the disease incidence per 100,000 persons. Vaccination coverages were obtained from the Vaccination Programme, Department of Health, Generalitat of Catalonia. ResultsThe highest hepatitis B incidence rates were observed in males aged 19-49 years (rate>4, P<.01), which corresponded to the population group with the highest percentage of immigration (>15%). The incidence rate decreased non-linearly over time (P<.01). The reduction in incidence due to vaccination programmes was significant (P<.01) but its effect was not linear. ConclusionGAM models showed that the reduction in hepatitis B incidence due to vaccination programmes was non-linear and the increases in the incidence occurred in a specific population group: male immigrants. The descriptive analysis by geographical area show the importance of including this factor in future studies. GAM models permit the evaluation of future vaccination planning.