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XIII] effective mosquito netting from mosquito bite during the first three or four days of their illness. Portability of the virus in fomites and merchandise.— Until recently it was universally believed that the virus might remain for a considerable time potentially infective in fomites, clothes, merchandise, etc., and in wooden structures (ships). Thus, Strain describes an epidemic in São Paulo in which he believed the initial cases acquired the infection from unpacking a box of clothes which had lain at Santos for some time and had been damaged there by damp and sea- water. The epidemic of 1893 in the same city he traced to certain cases of machinery which had lain for some months at Santos. On opening the cases the packing straw was found to be damp. Four of the people in the house where the cases were opened got yellow fever within a few days. Many similar instances have been adduced as conclusive evidence of the portability of the virus of yellow fever in fomites. But the very thorough and carefully conducted experiments carried out in Cuba by Drs. Reed, Carroll, and Agramonte go far to prove that fomites have nothing whatever to do with the conduction of the disease. A small, illventilated, badly lighted wooden hut was erected near Havana during the prevalence of epidemic yellow fever. The fresh and stale fomites of yellow - fever patients, in the shape of soiled bedding, clothes, black vomit, etc., were strewn about or stowed away in great profusion in this close hut, and among them, lying on beds that had been occupied recently by yellow -fever patients, wearing these patients' soiled night -clothes and using their soiled blankets, seven non-immunes (that is, white men, recently arrived and never previously affected with yellow fever) slept during, in the aggregate, sixty-three nights— from November 20th, 1900, to January 31st, 1901— with absolute impunity.

Immunity of the native as affected by anti-stegomyia sanitation.— The immunity of the native of the endemic areas of yellow fever is