Malaria infections are prevalent between 45 north and 40 south latitude. In certain areas these limits are wide. Malaria due to P. vivax is more widely distributed than the other types. It is the prevalent infection in most areas within the temperatezones, but is wide spread throughout the tropics as well. P. malariae is comparatively rare: it is observed most commonly in temperate areas and in the sub-tropics. P. falciparum tend to predominate throughout all tropical regions, P. ovale is relatively uncommon: the majority of cases have been reported from Africa, although some have been found in Asia, Europe and South America.
Most recently 3 species of malarial parasites of` monkey´s have been fonnd to infect man. Two of them have either been accidentally or experimentally´ transmitted by mosquitoes in the laboratory. More significantly in August 1965, another species has been isolated from a naturally acquired infection in man. We need now to know wheter any of these~ or of a large number of other species of simian par asites constitute zoonoses which may play a part in-human malaria.
And the problem of _the development of resistance-among malaria parasites to chemoprophylaxis and-chemotherapeutic agents has become one of increasing concern. Prior to 19481950, the only evidence of such resistance was the observation that some strains of malaria patients were less sensitive to quinine an& such drugs as mepacrine (atebrine) and pamaquine. In 1948 strains of P. falciparum and P. vivax recovered in Malaya were found to beresistant to paludrine. Resistance to this drug was also noted in Indonesia, Assam (NE India), New Guinea and Vietnam. In 1952, also in East Africa. Since 1954, pyrimethamine resistant strains of P. falciparum, P. vivax and P. malariae have been found in Kenya, Tanganika, Upper Volta, Nigeria, Ghana, Venezuela and Western New Guinea. The development of this resistance was, not viewed with alarm because the main reliance for prophylaxis and therapy rested upon chloroquine, especially for P. falciparum.
However, in 1959 and 1960 word began to drift back from the field of the slow or incomplete action of chloroquine. Such reports came from Nigeria, Upper Volta and Venezuela. At the time, the blame was placed on either inadequate dosage, failure to take the drug or malabsorption of the drug in cases complicated with diarrhea. In 1961, it was shown beyond doubt that a strain of P. falciparum originating in the Magdelena Valley of Colombia, South America was resistant to chloroquine. In 1963, Box et al reported chloroquine resistance in P. falciparum in North Brazil and Young et al, Alving & Powell reported in Thailand, Vietnam and other areas of Southeast Asia.
It is possible that personnel presently stationed in areas where resistant or less susceptible P. falciparum and P. vivax strains are present, might serve as "carriers" and introduce these strains into areas of the Korea where are breeding of A. hyrcanus inensis which are more or less playing as vector of malaria in Vietnam. But some one belives that P. falciparum and P. malariae would not naturally infect to men in Korea except P. vivax. And author guess that the delayed attack and relapses of malaria infections may be occured in more or less.
And then author detected the asymptomatic malaria ´with thin or thick preparations by Gimsa´s blood stain about Korean troops who were stationed for about 7~8 month to examination since arrived in Vietnam October 1965.
The results observed are summerized as follows.
1) The incidence rate of asymptomatic malaria was 454 0/00. And the higher incident rate of malaria patients and the higher rate of asymptomatic malaria.
2) P. falciparum in human bodies were kept for 120 days more over in 2.6% at least.
3) Of millitary populations,1041, tested in the field, who were taking of chloroquine tablets as chemoprophylaxis every one week, 33(1/30) cases are admitted to hosiptal under the impression of malaria within 2 weeks after field test. Eighteen of these patients were conveniently diagnosed and others are remained as suspected cases. Of these exactly diagnosed, eight patients are aleady found in the field test. And of the other group. 222 soldiers who were tested soon after came back from Ducco neared the boundary of Camboeia, who were taking of chloroquine with dapson(Diarnino-Diphenyl-Sulfone) former is eery day later weekly 48(1/5) cases are admitted to hospital within 10 days after field test. And all are conveniently diagnosed. Of these diagnosed exactly, seven patients are aleady found in the field test.
4) Out of the Plasmodae detected 88.4% were P. falciparum, and P. vivax and P. malariae were 5.7% respectively.
5) The incidence rate is 136 0/00, lower in the Nam-Tang (9) group them are well known how to use of malaria pills and other personal preventive measures in more over than 80% of the tested troops than 275 0/00. of the Nam-Tang (10) group them are not well knowm how to use of preventive measures
6) Of sixteen cases of P. falciparum who were examined since 20 days after discharged, about 1/5 cases are failed of radical treatment with chloroquine and other antimalarial agents.
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