Epidemic non-A, non-B hepatitis in Nepal. Recovery of a possible etiologic agent and transmission studies in marmosets
M. A. Kane, D. W. Bradley, S. M. Shrestha, J. E. Maynard, E. H. Cook, R. P. Mishra and D. D. Joshi
An epidemic of non-A, non-B hepatitis occurred in Kathmandu Valley, Nepal,
during 1981-1982, with approximately 7.6% of households and 1.4% of
individuals affected. Cases occurred preponderantly in the 15- to
34-year-old age group (70%), with most cases (75%) occurring in males. A
high mortality rate (21%) occurred in pregnant women admitted to the
hospital. No single water source was implicated, but epidemic peaks
occurred during monsoon rains, and multiple opportunities for enteric
transmission existed. One of eight patient stools examined by immune
electron microscopy revealed aggregated, antibody-coated, 27-nm viruslike
particles when convalescent serum samples were used as sources of antibody.
Inoculation of two chimpanzees and four marmosets with a suspension of this
stool resulted in elevated liver enzyme activity in three marmosets. Fecal
excretion of 27-nm particles during the acute phase of disease (with
temporally coincident antigen activity by radioimmunoassay) was observed in
one marmoset, which also developed convalescent antibody against the
particles in the original inoculum.
