Seroprevalence of hepatitis A infection in a low endemicity country: a systematic review
Abstract Background In Canada – a low endemicity country, vaccines for hepatitis A virus (HAV) are currently recommended to individuals at increased risk for infection or its complications. Applying these recommendations is difficult because the epidemiology of HAV infection is poorly defined, compl...
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ftbiomed:oai:biomedcentral.com:1471-2334-5-56 2023-05-15T16:17:14+02:00 Seroprevalence of hepatitis A infection in a low endemicity country: a systematic review Pham, Ba' Duval, Bernard De Serres, Gaston Gilca, Vladimir Tricco, Andrea C Ochnio, Jan Scheifele, David W 2005-07-07 http://www.biomedcentral.com/1471-2334/5/56 en eng BioMed Central Ltd. http://www.biomedcentral.com/1471-2334/5/56 Copyright 2005 Pham et al; licensee BioMed Central Ltd. Research article 2005 ftbiomed 2007-11-11T15:34:44Z Abstract Background In Canada – a low endemicity country, vaccines for hepatitis A virus (HAV) are currently recommended to individuals at increased risk for infection or its complications. Applying these recommendations is difficult because the epidemiology of HAV infection is poorly defined, complex, and changing. This systematic review aimed to 1) estimate age-specific prevalence of HAV antibody in Canada and 2) evaluate infection-associated risk factors. Methods MEDLINE (1966–2005) and EMBASE (1980–2005) were searched to identify relevant studies for the systematic review. Archives for the Canada Diseases Weekly Report (1975–1991) and Canada Communicable Disease Report (1992–2005) were searched for relevant public health reports. Data were abstracted for study and participants' characteristics, age-specific prevalence, and risk factors. Results A total of 36 reports describing 34 unique studies were included. The seroprevalence in Canadian-born children was approximately 1% in ages 8–13, 1–6% in 20–24, 10% in 25–29, 17% in 30–39, and increased subsequently. In age groups below 20 and 20–29, age-specific seroprevalence generally remained constant for studies conducted across geographic areas and over time. Compared to Canadian-born individuals, subjects born outside Canada were approximately 6 times more likely to be seropositive (relative risk: 5.7 [95% CI 3.6, 9.0]). Travel to high risk areas in individuals aged 20–39 was associated with a significant increase in anti-HAV seropositivity (RR 2.8 [1.4, 5.5]). Compared to heterosexuals, men having sex with men were only at a marginally higher risk (adjusted odds ratio 2.4 [0.9, 6.1]). High risk for seropositivity was also observed for Canadian First Nations and Inuit populations. Conclusion Results from the current systematic review show that in this low endemicity country, disease acquisition occurs in adulthood rather than childhood. The burden of disease is high; approximately 1 in 10 Canadians had been infected by ages 24–29. The increase in prevalence in young adults coincides with disease importation and increasing frequency of risk factors, most likely behavioral-related ones. Gaps in seroprevalence data were identified rendering the application of current immunization recommendations difficult. A nationwide prevalence survey for all Canadians is needed. This is essential to quantify the effectiveness of current recommendations and conduct cost-effectiveness evaluations of alternative immunization programs, if necessary. Article in Journal/Newspaper First Nations inuit BioMed Central Canada |
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Abstract Background In Canada – a low endemicity country, vaccines for hepatitis A virus (HAV) are currently recommended to individuals at increased risk for infection or its complications. Applying these recommendations is difficult because the epidemiology of HAV infection is poorly defined, complex, and changing. This systematic review aimed to 1) estimate age-specific prevalence of HAV antibody in Canada and 2) evaluate infection-associated risk factors. Methods MEDLINE (1966–2005) and EMBASE (1980–2005) were searched to identify relevant studies for the systematic review. Archives for the Canada Diseases Weekly Report (1975–1991) and Canada Communicable Disease Report (1992–2005) were searched for relevant public health reports. Data were abstracted for study and participants' characteristics, age-specific prevalence, and risk factors. Results A total of 36 reports describing 34 unique studies were included. The seroprevalence in Canadian-born children was approximately 1% in ages 8–13, 1–6% in 20–24, 10% in 25–29, 17% in 30–39, and increased subsequently. In age groups below 20 and 20–29, age-specific seroprevalence generally remained constant for studies conducted across geographic areas and over time. Compared to Canadian-born individuals, subjects born outside Canada were approximately 6 times more likely to be seropositive (relative risk: 5.7 [95% CI 3.6, 9.0]). Travel to high risk areas in individuals aged 20–39 was associated with a significant increase in anti-HAV seropositivity (RR 2.8 [1.4, 5.5]). Compared to heterosexuals, men having sex with men were only at a marginally higher risk (adjusted odds ratio 2.4 [0.9, 6.1]). High risk for seropositivity was also observed for Canadian First Nations and Inuit populations. Conclusion Results from the current systematic review show that in this low endemicity country, disease acquisition occurs in adulthood rather than childhood. The burden of disease is high; approximately 1 in 10 Canadians had been infected by ages 24–29. The increase in prevalence in young adults coincides with disease importation and increasing frequency of risk factors, most likely behavioral-related ones. Gaps in seroprevalence data were identified rendering the application of current immunization recommendations difficult. A nationwide prevalence survey for all Canadians is needed. This is essential to quantify the effectiveness of current recommendations and conduct cost-effectiveness evaluations of alternative immunization programs, if necessary. |
format |
Article in Journal/Newspaper |
author |
Pham, Ba' Duval, Bernard De Serres, Gaston Gilca, Vladimir Tricco, Andrea C Ochnio, Jan Scheifele, David W |
spellingShingle |
Pham, Ba' Duval, Bernard De Serres, Gaston Gilca, Vladimir Tricco, Andrea C Ochnio, Jan Scheifele, David W Seroprevalence of hepatitis A infection in a low endemicity country: a systematic review |
author_facet |
Pham, Ba' Duval, Bernard De Serres, Gaston Gilca, Vladimir Tricco, Andrea C Ochnio, Jan Scheifele, David W |
author_sort |
Pham, Ba' |
title |
Seroprevalence of hepatitis A infection in a low endemicity country: a systematic review |
title_short |
Seroprevalence of hepatitis A infection in a low endemicity country: a systematic review |
title_full |
Seroprevalence of hepatitis A infection in a low endemicity country: a systematic review |
title_fullStr |
Seroprevalence of hepatitis A infection in a low endemicity country: a systematic review |
title_full_unstemmed |
Seroprevalence of hepatitis A infection in a low endemicity country: a systematic review |
title_sort |
seroprevalence of hepatitis a infection in a low endemicity country: a systematic review |
publisher |
BioMed Central Ltd. |
publishDate |
2005 |
url |
http://www.biomedcentral.com/1471-2334/5/56 |
geographic |
Canada |
geographic_facet |
Canada |
genre |
First Nations inuit |
genre_facet |
First Nations inuit |
op_relation |
http://www.biomedcentral.com/1471-2334/5/56 |
op_rights |
Copyright 2005 Pham et al; licensee BioMed Central Ltd. |
_version_ |
1766003076206952448 |