Lake Vera revisited: parity and survival rates of Anopheles punctipennis at the site of a malaria outbreak in the Sierra Nevada foothills of California.

Abstract

Parity and survival rates of Anopheles punctipennis were studied at the site of a 1952 outbreak of malaria in the Sierra Nevada foothills of California with the purpose of estimating blood feeding frequency and survivorship of such populations. Anopheles punctipennis was the dominant species in landing collections conducted for 20 consecutive nights in August and September 1990. The mean parity rate of An. punctipennis was 0.82. The gonotrophic cycle was estimated to last three days based on time series analysis of the number of nulliparous and parous mosquitoes collected each day. Survivorship was estimated to be 0.79 per gonotrophic cycle and 0.92 per day. Ovarian dilatation data indicated that some females had completed eight gonotrophic cycles prior to being collected and 45% of the females completed two or more cycles. The high prevalence of multiparous individuals, high parity rate, long survivorship and a short three-day gonotrophic cycle estimate indicates that this population is long lived and has a capacity to be an efficient vector of malaria.