Serologic evidence for hepatitis E virus infection among patients with undifferentiated acute febrile illness in Kibera, Kenya

Abstract

Background Hepatitis E (HEV) is an emerging cause of viral hepatitis mainly transmitted through the fecal-oral route. Residents of the Kibera slum of Nairobi, Kenya are at risk for fecal-orally transmitted infections. Objective To quantify the incidence and prevalence of HEV infection among acute febrile illness (AFI) cases using a population-based infectious disease surveillance network. Study Design Cross-sectional serum samples from AFI case-patients between 2009 and 2012 were matched to the age and gender distribution of the Kibera population and tested by IgM and IgG enzyme immunoassays (EIA) and nucleic acid testing (NAT). Serum from healthy residents was also tested by EIA. Results Of the 482 AFI serum samples tested, 124 (25.7%) and 182 (37.8%) were IgM and IgG reactive, respectively. On multivariate analysis, IgM reactivity was associated with HIV (RR 1.66, 95%CI 1.07, 2.60; p=0.024) while IgG reactivity was associated with increasing age (p<0.001) and HIV (RR 1.93, 95%CI 1.52, 2.46; p<0.001). AFI case-patients were more likely to be IgM (p=0.002) and IgG (p<0.001) reactive compared to healthy residents. The seroincidence by HEV-specific IgM was 84.0 per 1,000 person years, however, all 482 samples were negative by NAT. Conclusions Serologic evidence for HEV in Kibera suggests a high burden of infection, but NAT did not confirm HEV viremia. Additional testing is needed to determine whether EIAs are susceptible to false positivity in undifferentiated AFI populations before their widespread use.

Hepatitis E in Sub Saharan Africa – A significant emerging disease

“…Of the studies in the general population, 7 were on blood donors with IgG seroprevalence ranging from 4.6–47.8%. IgM seroprevalence and therefore risk of HEV contaminated donor blood was 3.1–5.9% [ 53 , [60] , [61] , [62] , [63] , [64] ]. Also, 3 of the studies were from Burkina Faso which showed a significantly higher prevalence than other countries increasing over time (19% in 2012 to 40% in 2014).…”

“…In 2 cohort studies, no significant difference was reported in HEV prevalence between people with and without HIV [ 90 , 91 ]. In contrast, both Furukawa et al [ 64 ] and Jacobs et al [ 82 ] found that HIV infection significantly increased the likelihood of HEV infection. Caron et al [ 72 ] found that HIV viral load was significantly higher in pregnant women testing positive for anti-HEV IgG (1.3E+05 vs 5.7E+04 copies per ml; p ≤ 0.02).…”

Setting a course for preventing hepatitis E in low and lower-middle-income countries: A systematic review of burden and risk factors

“…Data on risk factors for HEV infection (defined by IgM antibodies or RNA), disease, and death were identified in 36 studies (17,21,26,30,34,46,63,68,74,85,91,92,102,104,(108)(109)(110)112,116,129,138,139,(145)(146)(147)(148)(149)(150)(151)(152)(153)(154)(155)(156)(157)(158) from 13 countries between 1990 and 2017. One study only reported risk factors with an unknown hypothesized direction of effect and was excluded from further analysis (159).…”

Seroprevalence of Hepatitis E Virus among Voluntary Blood Donors in Nairobi County, Kenya: A Pilot Study

“…Transmission of HEV primarily occurs by the fecal-oral route via contamination of drinking water and food supplies [3]. Parenteral as well as vertical transmission may also occur particularly in endemic regions; however person to person transmission is uncommon.…”

“…Journal of Biosciences and Medicines 37.8% (IgG)[3]. It would be expected that healthy blood donors would have a lower seroprevalence compared to febrile patients since HEV is a known cause of febrile illness.…”