a handbook of the mosquitoes of north america - Systematic Catalog ...

54 MOSQUITOES OF NORTH AMERICA
the disease. for the rest of its active life; in one case 59 days
after receiving the infection.
As there is at present no specific treatment for yellow fever,
the only known method of reducing the disease is to prevent
this mosquito from biting or prevent its breeding. As a com-
plete elimination of its breeding grounds is not always feasible,
the prevention of mosquito infection becomes one of the most
important factors in a yellow fever outbreak.
Yellow fever, though formerly widespread in the tropical
portions of the Americas, has been almost eliminated. The
last great outbreak in North America occurred in New Orleans
in 1905. At the present time an outbreak may occur if the
disease should appear and the mosquito is present to become
infected. That there are human carrier? of this disease, as in
malaria, is believed by some workers but there seems no posi-
tive evidence to substantiate this belief. At the present time
( 1929) there is an active center of yellow fever in West Africa.
Since the yellow fever mosquito occurs throughout much of
the tropical and sub-tropical regions of the entire world, the
possible spread of this disease to such countries as Asia should
fill us with the utmost alarm. It is therefore highly desirable
that every possible effort should be made to eliminate the breed-
ing of this mosquito in North America. Without the mosquito,
the introduction of “carriers,” if they exist, would not bring
about any outbreak of the disease.
Unfortunately, recent researches in West Africa demonstrate
that yellow fever (the type of this disease now prevalent there)
is transmitted by other species of mosquitoes. Bauer (1928)”
’ A “carrier,” in the case of malaria, is one who has recovered
from the disease and has the micro- and macro-gametocytes in his
blood capable of infecting mosquitoes; or he may be one who has
never shown symptoms of the disease and still have the sexual stages
in the blood. Whether such occur in yellow fever is not known since
we know scarcely anything about the organism which causes the
disease.
’ Bauer, Amer. JZ. Trap. Med., 8, p. 261, July, 1928.