FIG. 8.

Timeline of events during ANDV infection of hamsters. Hamsters were injected intramuscularly (i.m.) with 2,000 PFU of ANDV on day 0. On day 4, apoptosis of lymphocytes was first detected. Numbers of apoptotic lymphocytes increased with time, as illustrated by the expanding wedge. Day 5 is the last day that the passive transfer of neutralizing antibodies (Nabs) protected against lethal disease (21). By day 6, animals became viremic, inclusions became visible in the liver, and focal pulmonary edema was first detected. Endothelial cell inclusions were first detected on day 8, 1 day before the earliest deaths. During the late stages of infection, there was leukocytosis and lymphopenia and finally severe pulmonary edema and death. E.M., electron microscopy.