Hepatitis A and E Viruses in Ouagadougou Figure 3. Evaluation of relation-ship between Wantai and Dia.Pro test results in positive samples. Crosses indicate blood donor samples and red squares samples from pregnant women. Linear correlations are significant within the two group but with significantly less dispersion of the blood donor samples than of the samples from pregnant women. The blue line indicates the cut-off level for the Wantai kit, and the red line the cut- off for the Dia.Pro kit. doi:10.1371/journal.pone.0048125.g003 subject to such limitations but may have presented other biases as it included only young adult women attending prenatal clinics. Nevertheless, these two groups together may be fairly represen- tative of the general population. Hepatitis, manifest as jaundice, is common in Burkina Faso, but biological investigations are often conducted late, limited to chronic disease and involve only HCV and HBV testing. Cases of acute hepatitis may be diagnosed without determining either the virology of the infection or whether the jaundice is HBV- (HbsAg) negative. There have been few investigations of anti-HAV seroprevalence [36]. Our study detected HAV infection endemi- cities of 14.3% (CI95 [7.1–21.5%]) in blood donors and 23% (CI95 [14–31%]) in pregnant women. The difference between these two groups could be due by the close proximity of these women to children who are considered to be potential carriers of the virus [37,38]. The seroprevalence of anti-HAV IgM indicates that the incidence of infections is relatively high and that there is a risk of major outbreaks if vaccination is not continued. The proportions of anti-HAV seropositives in the different age groups of blood donors revealed a high prevalence (50%) in the group of 46–55 year olds. The different rates of seropositivity between the different age groups suggests age-related HAV exposure in Burkina Faso, a phenomenon probably associated with the severity of the disease increasing with age. In the United States, the hospitalization rates for hepatitis A infections are 3% for individuals younger than 18 years and 13% for individuals older than 18 years. The fatality rate is 0.3% overall, but it is higher than 2% for individuals over 40 years old [12]. The seroprevalence we observed in the 26–35 year old group (18.7%) agreed with the findings of Dubois et al. (1992), Denis et al. (2003), and Poda (2010) [36,39,40], and is consistent with the idea that young adults are the most highly exposed and sensitive to infection. Indeed, the dietary habits of young adults, who frequently choose ready-to-eat food and fast-food, have been recognized as health-risk factors because poor quality control and undercooking of these products are commonplace in Burkina Faso [32]. Studies in other emerging or developing countries around the world have shown that the prevalence of HAV infection decreases as the living conditions of the populations improve [41–46]. This in accordance with the situation in Burkina Faso characterized by its low income and the poor hygienic status of a major part of population in the capital Ouagadougou, associated with high prevalence of hepatitis. Indeed, the causes of acute hepatitis, the most common clinical sign of HAV and HEV infection, led us to evaluate the prevalence of these two viruses in parallel in our population. Recently, the use of the ‘‘Wantai’’ kit in the UK and France led to the identification of higher rates of HEV positivity than suggested by previous studies using the Dia.pro kit. However, when we tested our Burkina Faso cohort in blind using both Table 2. Prevalence of anti-HEV IgG in pregnant women and blood donors per sampling period (Dia.Pro test). Year and marker Blood donors 2011 IgG March 2012 IgG Women (n = 22) 5 (23% CI95 [5–40%]) Women (n = 25) 6 (24% CI95 [7–40%]) doi:10.1371/journal.pone.0048125.t002 Men (n = 67) 11 (16.4% CI95 [7–25%]) Men (n = 64) 12 (18.7% CI95 [9–28%]) Pregnant women (n = 100) 9 (9% CI95 [3–14%]) (n = 89) 13 (9% CI95 [7–22%]) PLOS ONE | www.plosone.org 4 October 2012 | Volume 7 | Issue 10 | e48125