Little is known of the medical importance of Aedes vexans nocturnes 
(Theobald). However, it is suspected of being a vector of Japanese "B" Encephali¬ 
tis on Guam. The virus has been shown to be experimentally transmitted in the 
laboratory (Horsfall, 1955). 
In comparing Aedes vexans noctumus with its closely related Aed es vexans 
vexans found on the mainland United States; -the female of the subspecies 
noc liitous bites man readily, but it is not as persistent as the subspecies vexans. 
The mainland subspecies has been found to be naturally infected with western 
® 9 Uine encephalitis and has experimentally transmitted the eastern equine 
and St. Louis encephalitis viruses (King et. al., i 960 ). It is also capable 
of transmitting fowl pox experimentally and is a fairly efficient vector for 
—-T°fil&ria immitis (Leidy). For these reasons, the subspecies nocturnus has 
vector possibilities. 
4 
3. Mosquito-bo me diseases in Hawaii 
The only mosquito-borne disease occurring in epidemic proportions on the 
Hawaiian Islands was dengue; outbreaks occurring in 1903, 1912, and 1943-44. 
ine period between 1943~44 was the worst. The incidence in Honolulu was by far 
the nighest during this time, with 1,482 reported cases; in addition, there 
were three reported cases centered in the middle 'of Oahu, five cases in the 
Iearl Harbor area, and six cases on windward Oahu. During this same period, 
there were two reported cases in K©loa, Kauai and four cases in Hana, Maui. 
Between 1935 and 1962 there were 521 reported cases of malaria on Oahu. 
A total of 472 of these cases were reported between 1949 and 1955. The incidence of 
cases was mostly among military personnel; because there are no Anopheles 
mosquitoes on the Hawaiian Islands, the causal organism (Plasmodia) is said to 
have come in by military personnel from Southeast Asia. It i 3 to be noted that 
one case was attributed to a blood transfusion# 
3 Personal contact with Dr. Charles R. Joyce, Medical Entomologist, U.S.P.H.S . 
Quarantine Branch, Honolulu, Hawaii. 
4 H?aTTh%tpC^o^ifc, Dr &®f. rt p <">ington Jr., M.D., Epidemiologist, State 
