Proposed Algorithm for Hepatitis E Virus Diagnosis in the Early Phase of Illness.

Hepatitis E virus (HEV), a major etiologic agent of enterically transmitted hepatitis worldwide, is known to cause outbreaks. Diagnosis of the causative agent is important for patient management, understanding epidemiology and outbreak mitigation. We attempted to develop an algorithm for molecular diagnosis and compared the diagnostic accuracy of 2 of HEV IgM ELISA tests during an outbreak. Eighty-four blood samples collected during an outbreak in central India were referred to a nodal laboratory for confirmation of diagnosis. The samples were tested by serological and molecular testes. The results were analyzed by statistical tests. Both the IgM ELISAs were equally competent to diagnose HEV infection when samples were collected after 7.95 ± 3.2 days of onset of illness, whereas nRT-PCR proved a better test when samples were collected between 0 and 6.17 ± 1.97 days of illness. During HEV outbreaks, it is not possible to test all suspected cases by both serological and molecular tests; we suggest testing all ELISA-negative and samples collected in early phase (<7 days) of illness by molecular tests to rule out false-negative results. More studies with large sample size will aid in designing national guidelines for molecular diagnosis of HEV.