Dataset Information

A large outbreak of Hepatitis E virus genotype 1 infection in an urban setting in Chad likely linked to household level transmission factors, 2016-2017.

ABSTRACT: In September 2016, three acutely jaundiced (AJS) pregnant women were admitted to Am Timan Hospital, eastern Chad. We described the outbreak and conducted a case test-negative study to identify risk factors for this genotype of HEV in an acute outbreak setting.Active case finding using a community based surveillance network identified suspected AJS cases. Pregnant or visibly ill AJS cases presenting at hospital were tested with Assure® IgM HEV rapid diagnostic tests (RDTs) and some with Polymerase Chain Reaction (PCR) in Amsterdam; confirmed cases were RDT-positive and controls were RDT-negative. All answered questions around: demographics, household makeup, area of residence, handwashing practices, water collection behaviour and clinical presentation. We calculated unadjusted odds ratios (ORs) and 95% confidence intervals (95% CI).Between September and April 2017, 1443 AJS cases (1293 confirmed) were detected in the town(attack rate: 2%; estimated 65,000 population). PCR testing confirmed HEV genotype 1e. HEV RDTs were used for 250 AJS cases; 100 (40%) were confirmed. Risk factors for HEV infection, included: having at least two children under the age of 5 years (OR 2.1, 95%CI 1.1-4.3), having another household member with jaundice (OR 2.4, 95%CI 0.90-6.3) and, with borderline significance, living in the neighbourhoods of Riad (OR 3.8, 95%CI 1.0-1.8) or Ridina (OR 3.3, 95%CI 1.0-12.6). Cases were more likely to present with vomiting (OR 3.2, 9%CI 1.4-7.9) than controls; possibly due to selection bias. Cases were non-significantly less likely to report always washing hands before meals compared with controls (OR 0.33, 95%CI 0.1-1.1).Our study suggests household factors and area of residence (possibly linked to access to water and sanitation) play a role in HEV transmission; which could inform future outbreak responses. Ongoing sero-prevalence studies will elucidate more aspects of transmission dynamics of this virus with genotype 1e.

SUBMITTER: Spina A

PROVIDER: S-EPMC5703542 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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A large outbreak of Hepatitis E virus genotype 1 infection in an urban setting in Chad likely linked to household level transmission factors, 2016-2017.

Spina Alexander A Lenglet Annick A Beversluis David D de Jong Marja M Vernier Larissa L Spencer Craig C Andayi Fred F Kamau Charity C Vollmer Simone S Hogema Boris B Irwin Andrea A Ngueremi Yary Roger R Mahamat Ali Açyl A Moussa Ali A Alfani Prince P Sang Sibylle S

PloS one 20171127 11

<h4>Background</h4>In September 2016, three acutely jaundiced (AJS) pregnant women were admitted to Am Timan Hospital, eastern Chad. We described the outbreak and conducted a case test-negative study to identify risk factors for this genotype of HEV in an acute outbreak setting.<h4>Methods</h4>Active case finding using a community based surveillance network identified suspected AJS cases. Pregnant or visibly ill AJS cases presenting at hospital were tested with Assure® IgM HEV rapid diagnostic t ...[more]

PMID: 29176816

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Dataset Information

A large outbreak of Hepatitis E virus genotype 1 infection in an urban setting in Chad likely linked to household level transmission factors, 2016-2017.

Publications

A large outbreak of Hepatitis E virus genotype 1 infection in an urban setting in Chad likely linked to household level transmission factors, 2016-2017.

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