Jf. Day et Ga. Curtis, ANNUAL EMERGENCE PATTERNS OF CULEX-NIGRIPALPUS FEMALES BEFORE, DURINGAND AFTER A WIDESPREAD ST-LOUIS ENCEPHALITIS EPIDEMIC IN SOUTH FLORIDA, Journal of the American Mosquito Control Association, 9(3), 1993, pp. 249-255
Resting Culex nigripalpus females were collected from the same site at
least 3 times a week from January 1986 through December 1991. Newly e
merged mosquitoes were used to monitor annual emergence patterns that
were rainfall driven. Four of the years, 1986-89, preceded the 1990 St
. Louis encephalitis (SLE) epidemic in south Florida. The pre-epidemic
period averaged 4 emergences per year, with most occurring during Jul
y and August. The emergence patterns observed during the epidemic year
were unusual in their early start in May and June and in the total nu
mber (11) observed. Adult mosquito emergences in 1991 were similar to
those in 1990, with an early start and a total of 14 observed, yet no
SLE transmission was recorded in Indian River County during 199 1. A t
ime series analysis of the 6-year data set showed a significant cross-
correlation between the emergence of Cx. nigripalpus females and heavy
(>50 mm) rains. A significant adult emergence occurred 5-8 days and 1
2-15 days following a heavy rainfall event.