Die Orthopädie des praktischen Arztes

1910 Journal of the American Medical Association (JAMA)  
In many malarial regions it is important that the varieties of mosquitoes common to such regions should be recognized, their breeding-habits studied and a determination made of the species of anophelines capable of transmitting the disease. This is explained by Samuel T. Darling, chief of the laboratory of the board of health of the Canal Zone, in a pamphlet issued by the Isthmian Canal Commission. The anophelines insusceptible to malaria may be more limited in their choice of breeding-places
more » ... f breeding-places than the other varieties, so that in the work of malarial mosquito destruction the latter may be disregarded, and attention given wholly to the breeding places of those varieties responsible for the transmission of malarial fever. With regard to man as a host it is necessary to have some knowledge of the limits of his infectiousness, i. e., the number of the sexual forms of the parasite in the blood necessary to infect susceptible mosquitoes. Other matters of importance are latent malaria, the effect of quinin on the parasites in man, the value of larvacides, algacides, agents destructive of ditch-grass, the size of screen mesh necessary to keep out mosquitoes, etc. After giving a minute description of the different species of anophelines and naming those susceptible to infection with the malarial parasites as shown by his experiments, together with the methods of conducting the experiments, collecting the larva', breeding, biting and infec¬ tion experiments, estimation of gametes, care of the mos¬ quitoes after biting, examining for zygotes, description of the malarial parasites in the mosquitoes, blood examinations, etc.. furling states that it was noticed that patients were iliscliarged from the hospital after the temperature was normal but while the peripheral blood still contained more than a K|iflicientnumber of gametes to infect susceptible mosquitoes. Experiments were therefore carried out to determine the limit°f infectiousness of such individuals, and it was found that Persons with more than 2 gametes per centimeter must be regarded as gamete-carriers, and should not be discharged or treatment discontinued until the gametes were reduced well helow the limit of iiifcetiousness, which was determined to be 1 gamete for every 500 leukocytes, This question of the complete destruction of the sexual forms in man is generally Overlooked, but, is important in delimiting malaria, and may be accomplished by appropriate, quinin treatment of all gamete "arriéis. Thirty grains of quinin sulphate daily is an efficient dosage for the purpose, although this quantity had no effect°" the development of the parasites in infected mosquitoes "'d on the blood of individuals taking this amount of quinin. The effect of quinin administration is to make the gametes 111 the tertian form, at leost, gradually disappear from the Peripheral blood of the patient by the destruction of the •Vl|ung fornis, the gametes being phagoeyted by splenic and "epatic endotheliumj this will occur in from a few days to a few weeks, depending on the severity of the infection. There ai'e never as many gametes in the peripheral blood in the '•'I'tiun form as in I he estivo-autumnal form. Til the investi-•
doi:10.1001/jama.1910.04330120071035 fatcat:vpvrf4v2njhf3p5fvvwiqpo23u