Growth Studies of California Encephalitis Virus in Two Aedes Mosquito Cell Line Cultures

Abstract

The mouse-adapted New York strain of California encephalitis (CE) (Whitney et al., 1969) virus grew readily on initial passage in cultures of Singh’S (1967) Aedes aegypti and A. albopictus cell lines. The infection persisted over the observation period of 6 weeks. Subsequent experiments with another CE strain have shown that cells on passage still produce virus and are persistently infected. Cytopathic effects were not observed during the first and subsequent 8 passages after which the experiments were discontinued. Fig. 84 shows a comparison of the growth of CE virus on initial passage in two Aedes cell lines. A slight and gradual drop in titer of extracellular virus was demonstrated. The virus titer in A. albopictus cells was 5.9 LD₅₀/ml and generally 1 log₁₀ higher than that observed in A. aegypti cells. In the absence of cells, no virus was detected by the fifth post-inoculation day in the original inoculum incubated at the same temperature.