Journal of Viral Hepatitis

Hendrickx, G.; Van Herck, K.; Vorsters, A.; Wiersma, S.; Shapiro, C.; Andrus, J. K.; Ropero, A. M.; Shouval, D.; Ward, W.; Van Damme, P.

doi: 10.1111/j.1365-2893.2008.01022.xpmid: 18837827

Summary. For the first time a global meeting on hepatitis A virus (HAV) infection as vaccine preventable disease was organized at the end of 2007. More than 200 experts from 46 countries gathered to investigate the changing global HAV epidemiology reflecting the increasing numbers of persons at risk for severe clinical disease and mortality from HAV infection. The benefits of childhood and adult hepatitis A (HepA) vaccination strategies and the data needed by individual countries and international health organizations to assess current HepA prevention strategies were discussed. New approaches in preventing HAV infection including universal HepA vaccination were considered. This introductory paper summarizes the major findings of the meeting and describes the changing epidemiology of HAV infections and the impact of HepA vaccination strategies in various countries. Implementation of HepA vaccination strategies should take into account the level of endemicity, the level of the socio‐economic development and sanitation, and the risk of outbreaks. A stepwise strategy for introduction of HepA universal immunisation of children was recommended. This strategy should be based on accurate surveillance of cases and qualitative documentation of outbreaks and their control, secure political support on the basis of high‐quality results, and comprehensive cost‐effectiveness studies. The recognition of the need for increased global attention towards HepA prevention is an important outcome of this meeting.

Gentile, A.

doi: 10.1111/j.1365-2893.2008.01023.xpmid: 18837828

Summary. Universal hepatitis A (HA) vaccination was implemented by the Argentinean Ministry of Health in June 2005 with a single dose at age 12 months. The decision was made taking into account the following factors. (1) Disease burden: The incidence rate for the disease increased from 2003 to 2004; the northern and western regions of the country were the most affected. Sero‐prevalence data for children 1–15 years old was 54% for the whole country, with differences per region and age. From May 1982 to September 2002, 210 patients were recruited with acute hepatic failure; HA was the aetiology in 61% of them. (2) Cost‐effectiveness: Compared with no vaccination, the one‐dose schedule would save US$15.3 millions, with regional variations. (3) Vaccine features: Immunization with one‐dose schedule HA vaccine confers good immunogenicity and effectiveness. (4) Programmatic feasibility: The National Immunizations Program has appropriate distribution system for vaccines, with adequate cold chain. (5) Social acceptance and political compromise: The population largely accepts HA vaccination and the national authorities should be committed to providing it regularly. The main global issue is that hepatitis A virus infection remains the most commonly reported vaccine‐preventable disease in many parts of the world despite the availability of vaccines.

Vitral, C. L.; Souto, F. J. D.; Gaspar, A. M. C.

doi: 10.1111/j.1365-2893.2008.01024.xpmid: 18837829

Summary. Recent studies have shown that the prevalence of antibody to hepatitis A virus (HAV) is decreasing in several Latin American countries. Brazil is a very large and heterogeneous country, showing striking regional differences. With regard to sanitary facilities, 81.7% of the districts in the south‐eastern region have sewage systems, compared with only 5.8% in the northern region. Results of sero‐epidemiological studies and reported hepatitis A outbreaks indicate a change in the epidemiological pattern of hepatitis A in the country. Individuals, especially those under the age of 10, are mostly unprotected from HAV infection, regardless of their socioeconomic status. During 2000–2005, approximately 14 000–21 000 cases of hepatitis A were reported annually in Brazil, a rate of 7.5–11 cases per 100 000 population. Nationwide, hepatitis A mortality rates declined progressively from 1980 to 2002. As fatal cases constitute a small, but predictable, portion of all acute hepatitis A cases, which are in turn part of the total number of HAV infections, these data suggest that there has been a decline in HAV circulation in all Brazilian regions over the last two decades. Taken together these facts point out that the epidemiological pattern of hepatitis A is changing in Brazil. Besides improvements in sanitary conditions in the poorest Brazilian regions, the introduction of hepatitis A vaccination of young children could be a strategy for controlling HAV infection in the country.

Tosti, M. E.; Spada, E.; Romanò, L.; Zanetti, A.; Mele, A.; Mele, A.

doi: 10.1111/j.1365-2893.2008.01025.xpmid: 18837830

Summary. The incidence of, and risk factors for, acute hepatitis A (AHA) were assessed by using data collected from the Italian surveillance system of acute viral hepatitis (SEIEVA). To this end, a case–control study within a population‐based surveillance for acute viral hepatitis was performed. AHA incidence has been estimated since 1991; the association with considered risk factors was analysed from 2001 to 2006 employing cases of acute hepatitis B (AHB) as controls. The incidence of AHA declined from 4 / 100 000 in 1991 to 1.4/100 000 in 2006, with a peak during 1996–1998 due to an outbreak in southern Italy. The incidence of AHA was highest among persons aged 15–24 years. The case‐fatality rate was 2.9 / 10 000. Contact with individuals with AHA (adjusted OR (ORadj) = 3.8, 95% CI 2.7–5.5; population‐attributable risk (PAR) = 7.5%), travelling to endemic areas (ORadj = 3.1, 95% CI = 2.6–3.8; PAR = 19.5%), ingestion of raw shellfish (ORadj = 1.8, 95% CI = 1.6–2.1; PAR = 26.6%), and cohabitation with day care children (ORadj = 1.3, 95% CI = 1.01–1.7; PAR = 2.3%) were the main important risk factors. In 2003, an outbreak, with high case‐fatality rate occurred among intravenous drug users, in a central Italian town. A weak association was found for male homosexuality when acute hepatitis C cases were employed as controls (ORadj = 1.4 CI, 95% CI = 1.1–1.9). Hepatitis A virus infections are currently occurring more frequently in adults, in whom the disease is most severe. In conclusion, looking at the attributable risks, at present most of the AHA infections are due to shellfish consumption, travel to endemic areas and contact with patients with AHA. Vaccination of individuals at increased risk of infection, as well as persons with underling liver disease and those at increased risk of complications, combined with surveillance of shellfish retail outlets are efficient control measures.

Xu, Zhi‐Yu; Wang, Xuan‐Yi; Liu, Chang‐Qing; Li, Yang‐Ting; Zhuang, Fang‐Chen

doi: 10.1111/j.1365-2893.2008.01026.xpmid: 18837831

Summary. The objective of the study was to identify the protective factors for the rapid decline in the risk of hepatitis A virus (HAV) infection in China between 1990 and 2006. Results of serological follow‐up and data on annual hepatitis A incidence were analysed and correlated with economic growth and HAV vaccine output during the same period. In conclusion, both HAV vaccination and changing lifestyles associated with the booming economy contributed to the rapid risk decline. Changing lifestyles played a major role in the decline especially in the areas with booming economy.

Shliakhtenko, L.; Plotnikova, V.; Levakova, I.; Rubis, L.; Solovieva, E.; Mukomolov, S.

doi: 10.1111/j.1365-2893.2008.01027.xpmid: 18837832

Summary. The epidemiological features of hepatitis A virus (HAV) infection were studied in eleven territories located in the north‐western region of the Russian Federation. The dynamics of HAV infection in Russia and in the region were evaluated during a 17‐year period. The age‐specific incidence was calculated and 229 305 patients with acute HAV were identified. The analysed database included HA mixed with other viral hepatitis infections: it included information about 8 809 HAV patients. Special attention has been paid to the sero‐epidemiological studies conducted in St Petersburg city. These studies included analysis of age‐specific incidence in persons 20 years of age and older during 6 years and testing of blood sera from 1 892 healthy persons for IgG anti‐HAV. In general there is a trend to reduction of HAV incidence in Russia, and in the north‐western region, high indices were registered in some provinces in different years. It was established three types of age‐specific incidence distribution: predominated incidence in 3–14 years of age (first type), 15–29 years of age (second type) and uniform distribution in different age groups (third type). It was shown that decrease of HAV incidence in children and young adults lead to the reduction of sero‐positivity level in the groups 20+ years of age. These characteristics should be taken in account to define indications for HAV vaccine prophylaxis. HAV infection in 10–13% of cases mixed with acute or chronic hepatitis B and C in the last 15 years in St Petersburg. In the middle of 1990s, HAV mostly mixed with acute viral hepatitis of different aetiology, but in the modern time predominated type of mixture was presented by HAV and chronic HBV and HCV infections. The obtained results are useful for viral hepatitis surveillance and control.

Moisseeva, A. V.; Marichev, I. L.; Biloschitchkay, N. A.; Pavlenko, K. I.; Novik, L. V.; Kovinko, L. V.; Lyabis, O. I.; Houillon, G.; Rasuli, A. M.

doi: 10.1111/j.1365-2893.2008.01028.xpmid: 18837833

Summary. Ukraine is a zone of moderate hepatitis A endemicity. The changing epidemiology of the disease because of improved hygiene has shifted the burden of Hepatitis A to older age groups where the disease is more severe. Outbreaks have also become more common as more of the population has become susceptible to hepatitis A virus (HAV). To help guide decisions regarding use of hepatitis A vaccine in Ukraine, we examined the presence of antibody to HAV (anti‐HAV) in 1001 persons aged 1 to 85 years, visiting four municipal healthcare centres in the Ukrainian capital, Kiev. Overall, the anti‐HAV prevalence was 31.9%. Anti‐HAV seropositivity increased with age from 9.2% among children aged 1–5 years to 81.7% among persons over 50 years, but less than 50% of subjects less than 50 years were HAV seropositive. No children under 2 years were seropositive. HAV seropositivity was twice as high in children aged 5–11 years old in the low socio‐economic status group (income less than 150 US$ per family member per month) than in the middle/high group (11.1% compared to 6.3%) but this disparity disappeared by adolescence. The prevalence of anti‐HAV antibodies in adults was not different with respect to district of residence within the city. Considering the proportion of HAV seronegative subjects in all age groups under 50 years, routine vaccination against HAV of children aged 1–2 years old would appear to be an effective schedule for hepatitis A prophylaxis in Kiev.

Vacchino, M. N.

doi: 10.1111/j.1365-2893.2008.01029.xpmid: 18837834

Summary. In Argentina, the annual incidence rate of reported hepatitis A disease ranged from 70.5 to 173.8 per 100 000 during 1995–2004. A single dose universal hepatitis A immunization program aimed at children aged 12 months was started in June 2005. The aim was to observe the impact of universal vaccination against hepatitis A in Argentina. A longitudinal analysis of hepatitis A rates reported in Argentina since 1995 to the National Notifiable Diseases Surveillance System (SINAVE). Incidence rates in 2007 were compared with those for the prevaccination baseline period (1998–2002), overall and by age group and geographical regions. Overall vaccine coverage in Argentina was 95% in 2006 for the single dose. After initiating the program, a sharp decrease in disease rates was observed. The annual incidence of 10.2 per 100 000 during 2007 represents 88.0% reduction with respect to the average incidence rate for the period 1998–2002 (P < 0.001). For children aged 1 year, an 83.1% reduction in disease was observed in 2007, compared with the baseline period (P < 0.001). Furthermore, a sharp decline was also observed in all other age groups 87.1% (2–4 years), 88.7% (5–9 years), 83.6% (10–14 years), 78.8% (15–49 years), 20.7% (>50 years). Also important reductions were observed in all Argentinian regions. Following the implementation of universal hepatitis vaccination with a single dose to children at 12 months of age, hepatitis A rates have declined substantially in Argentina. Monitoring is needed to verify that vaccination continues to proceed and that low rates are sustained.

Domínguez, A.; Oviedo, M.; Carmona, G.; Jansá, J. M.; Borrás, E.; Salleras, L.; Plasència, A.

doi: 10.1111/j.1365-2893.2008.01030.xpmid: 18837835

Summary. A universal vaccination program for preadolescents, aged 12 years, with the hepatitis A + B vaccine was introduced in 1998 in Catalonia (Spain) with the aim of protecting the whole population against hepatitis A. The hepatitis A + B vaccine program replaced the hepatitis B vaccination program for preadolescent started in 1991. The impact of the hepatitis A + B vaccination program was studied by assessment of the trend of reported cases of hepatitis A. All cases of viral hepatitis reported from 1992 to 2006 were included in the study. To evaluate changes in the epidemiology of hepatitis A, two periods were considered: a prevaccination period (1992–1998) and a post‐vaccination period (2001–2006). The ratios of the rates were calculated according to age and sex. The comparison of rates and proportions was made by calculation of the normal z statistic. A total of 7536 cases of viral hepatitis were reported, of which 4109 (54.52%) were hepatitis A. The incidence rate of hepatitis A fell from 5.44 per 100 000 person‐years in the prevaccination period to 3.02 in the post‐vaccination period. In males, the rate fell from 6.85 to 3.89 and in females from 4.10 to 2.18. The male‐female ratio of incidence rates was lower in the post‐vaccination period. In males the global decline of incidence rate was 43.26% and in females 46.96%. The greatest decline occurred in the 15 to 19 years age group in both sexes (79.1% in men and 78.34% in women) but declines in the 10–14 years age group were also very important (69.21% and 67.88%, respectively). In conclusion, hepatitis A incidence fell in Catalonia in the post‐vaccination period in vaccinated adolescents and also in other unvaccinated groups who have benefited from the indirect effects of the vaccination program.

Fisenka, E. G.; Germanovich, F. A.; Glinskaya, I. N.; Lyabis, O. I.; Rasuli, A. M.

doi: 10.1111/j.1365-2893.2008.01031.xpmid: 18837836

Summary. Hepatitis A is a reportable disease in Belarus. Universal hepatitis A vaccination of children aged 6 years in Minsk City began in 2003. This analysis was conducted to evaluate the short‐term impact of the program. Hepatitis A incidence data from 1954 to 2006 was compiled. Vaccination effectiveness was estimated by comparing the incidence of reported hepatitis A cases after 4 years of immunization (2006) with the incidence when the vaccination program started (2003). The vaccines used were Avaxim 160™or Avaxim 80™ (95%) and Havrix 720™ (5%). From 2003 through 2006, hepatitis A incidence in vaccinated children under 14 years was 20‐fold lower than the incidence in unvaccinated children (0.3 cases/10000 vs 5.98/10000; odds ratio = 0.05, 95% CI: 0.012–0.202), for a vaccination effectiveness of 95%. The decreased incidence of hepatitis A in all age groups in 2006 (by 12 times in preschool children aged 1–5 years, 13 times in children aged 10–14 years and 4–6 times among adults), including those without high coverage by vaccination, suggest a herd effect. Routine vaccination also resulted in a shift of the age pattern of hepatitis A morbidity. The proportion of cases in children under 14 years decreased from 33% to 41% in 2000–2002 to 7% in 2005–2006. We conclude that introduction of universal hepatitis A vaccination in Minsk resulted in sharply reduced incidence in both vaccinated and unvaccinated children. Hepatitis A virus circulation might decrease further by beginning vaccination at a younger age.