Determination of Hepatitis E Virus Seroprevalence by Using Recombinant Fusion Proteins and Synthetic Peptides

Souto

Mem. Inst. Oswaldo Cruz

et al. 2002

We investigated the seroprevalence of hepatitis A virus (HAV) and hepatitis E virus (HEV) infection in subjects living in the community of Manguinhos, Rio de Janeiro, Brazil, and assisted Key words: hepatitis A virus -hepatitis E virus -seroprevalence -epidemiology -Rio de Janeiro -Brazil Viral hepatitis is a public health problem worldwide. Two of the agents that cause viral hepatitis are enterically transmitted: hepatitis A virus (HAV) and hepatitis E virus (HEV).In the last years, improvements in environmental sanitation and hygienic conditions, such as piped water and sewage system, have been responsible for a decrease in the endemicity level of hepatitis A in several developing countries. In Brazil, although hepatitis A is considered an endemic disease (Pannuti et al. 1985, Abuzwaida et al. 1987, Bensabath et al. 1987, Queiroz et al. 1995, data published in recent investigations carried out in the State of Rio de Janeiro revealed a shift in the hepatitis A epidemiological pattern. Improvements in life standards of some urban populations are responsible for a decrease in antibody prevalence among children and adolescents (Vitral et al. 1998a,b).HEV infection is quite common in some geographic areas like India, Africa and Southeast Asia, where it can represent the main cause of acute hepatitis (Arankalle et al. 1995 reported in these areas (Shakhgildyan et al. 1986, CDC 1987, Belyakov et al. 1990, Zuang 1992. On the other hand, epidemiological investigations in non-endemic areas show a low, but constant presence of anti-HEV antibodies (about 1.2%) in normal human populations (Balayan et al. 1996, Psichogiou et al. 1996, Irshad 1999.In 1986, the occurrence of outbreaks of HEV infection in the Americas was recognized in Mexico (Velazquez et al. 1990). More recently, two acute cases of hepatitis E were described in Argentina (Schlauder et al. 2000). In Brazil, outbreaks of hepatitis E have never been reported, although some authors found antibodies in some population groups (Focaccia et al. 1995, Parana et al. 1997, Souto & Fontes 1998, Trinta et al. 2001.Nowadays, hepatitis A can be prevented by active immunoprophylaxis and, for a better control of infection, it is necessary to investigate its current prevalence in different areas. On the other hand, further data are needed in order to evaluate the importance of HEV infection in our country. The aim of the present study was to evaluate the prevalence of HAV and HEV infections in an area where sanitary conditions were improved over the last few years. MATERIALS AND METHODSCalculation of sample size -The minimum sample size was estimated using the formula: n = Z² P Q / d², considering as n = estimated sample size; Z = reduced variable, which value is 1,96 when alpha = 0,05; P (estimated prevalence) = probability to achieve the studied phenomenon; Q (1-P) = complement of the estimated prevalence; d (desired precision) = margin of error.

Section: Discussionsupporting

confidence: 91%

Seroepidemiological markers of enterically transmitted viral hepatitis A and E in individuals living in a community located in the North Area of Rio de Janeiro, RJ, Brazil

Souto

Mem. Inst. Oswaldo Cruz

et al. 2002

Tropical Med Int Health

“…In that study, no hepatitis E-seropositive adults were identified among 35 persons tested (RichardLenoble et al 1995). The prevalence of hepatitis E in Tanzania is comparable to other regions of low endemicity, such as Europe and the United States (Paul et al 1994;Zanetti et al 1994;Mast et al 1997).…”

Section: Discussionmentioning

confidence: 94%

“…Hepatitis A (Sorin), C (Abbott) and E antibody (Abbott) (Paul et al 1994) seropositivities were determined by ELISA. Specimens reactive in the hepatitis C or E assays were repeated and considered positive only if repeatedly reactive in duplicate.…”

Section: Viral Hepatitis Assaysmentioning

confidence: 99%

Seroprevalence of viral hepatitis in Tanzanian adults

et al. 1998

SummaryIn a cross-sectional study in Dar es Salaam, Tanzania, we determined the seroprevalence of markers for hepatitis A, B, C and E viruses and examined associated risk markers. Among 403 healthy adults, the seroprevalence of antibodies to hepatitis A virus was 99.0% (95% confidence interval: 97.5-99.7). Prior exposure to hepatitis C and E viruses was rare (hepatitis C: 0.7% (0.2-2.1); hepatitis E: 0.2% (Ͻ 0.1-1.4)).The prevalence of all markers of hepatitis B was 70.7% (66.0-75.1). Hepatitis B surface antigen was identified in 6.0% (3.9-8.7) of subjects. Independent predictors of hepatitis B infection identified by logistic regression included older age, male gender, Muslim religion and type of abode. Given the high prevalence of hepatitis B and the low prevalence of hepatitis C, the majority of chronic viral hepatitis is likely to be associated with hepatitis B. Control efforts should focus primarily on hepatitis B.

Microbiology and Immunology

“…The genetic variation of the HEV genome has been demonstrated in different clinical isolates obtained from outbreaks of HEV in several areas (6,14,16). Recombinant antigens representing the putative structural gene sequence derived from open-reading frame (ORF) 2 and ORF3 of the HEV genome have been investigated extensively for the development of a test of recombinant-based enzymelinked immunosorbent assay (ELISA) or a Western blot assay for diagnosis of HEV infection (5,12,15). The newly developed serological diagnostic systems for HEV infection have been widely used to study the seroprevalence among different study populations of epidemic areas (3,9,12,15).…”

mentioning

confidence: 99%

“…Recombinant antigens representing the putative structural gene sequence derived from open-reading frame (ORF) 2 and ORF3 of the HEV genome have been investigated extensively for the development of a test of recombinant-based enzymelinked immunosorbent assay (ELISA) or a Western blot assay for diagnosis of HEV infection (5,12,15). The newly developed serological diagnostic systems for HEV infection have been widely used to study the seroprevalence among different study populations of epidemic areas (3,9,12,15). In order to demonstrate the prevalence of IgG antibodies to HEV (IgG anti-HEV) in Southern Taiwan, we have done a retrospective serological analysis in healthy individuals among different study populations.…”

mentioning

confidence: 99%

Prevalence of Antibody to Hepatitis E Virus among Healthy Individuals in Southern Taiwan

Peng

Lin

Chue

et al. 1995

The seroprevalence of hepatitis E virus (HEV) among 997 healthy individuals aged 6 to 84 years, collected between July 1993 and June 1994 at Kaohsiung-Pingtung area in Southern Taiwan was studied. Of the study populations of vegetable farmers, elementary school children, volunteer blood donors and college students, the prevalence of IgG anti-HEY ranged from 6.4% to 8.8%. In suburban elemantary school children of Mang-Chou Village at Pingtung-Hsien, the seroprevalence rate (9.6%) was significantly higher than the positive rate (1.5%) found in rural aboriginal elementary school of San-Min Village at Kaohsiung-Hsien. IgG anti-HEY antibodies were widely distributed among all age groups, with a significantly higher percentage (13.1 %) in the age group of 46-55 years old.