ABSTRACT
Electrophoretic studies were carried out on isozymes of 3 populations of Anopheles minimus collected from Guangxi and Yunnan Provinces of the People's Republic of China in 1993. Eight proteins were analyzed by 5% polyacrylamide gel electrophoresis. The most variable population, 'Yunnan-Field' (Y-F), was highly polymorphic at 14 of 20 loci (P = 0.700) with an average heterozygosity H of 0.340. P values of 0.500 and 0.700, and H values of 0.220 and 0.210 were obtained for each from 'Guangxi-Lab' (GX-L) and 'Yunnan-Lab' (Y-L), respectively, Nei's genetic distances (D) between Y-L and GX-L, Y-F and GX-L, and Y-F and Y-L were 0.1131, 0.1946 and 0.1069, respectively. These results suggest that GX-L is distant from the 2 other populations, Y-L and Y-F, and that this genetic differentiation between the 2 populations of Yunnan and Guangxi Provinces corresponds to the forms A and B, which were morphologically classified by Xu et al (unpublished).
Subject(s)
Animals , Anopheles/genetics , China , Electrophoresis, Polyacrylamide Gel , Female , Gene Frequency , Genetic Variation , Genetics, Population , Isoenzymes/geneticsABSTRACT
This paper presents the results of a study on simplified surveillance methods conducted in 23 pilot counties in 11 provinces and municipalities in China where reside 15 million people and malaria control has been in the late consolidation phase. Two simplified surveillance Schemes (A and B) taking treatment of clinical cases as the main measure were implemented in 1992-1994. The rate of annual blood examination for case detection was 1.0% in pilot Scheme A, while in areas of scheme B it was 0.3%. The implementation of both Scheme A and Scheme B, simplified or without treatment of infection foci and management of mobile populations, acquired satisfactory effects against malaria. Consequently, malaria incidence was declining steadily, only a few indigenous and introduced cases were detected. The parasite rate in residents and the IFA positive rate in children were very low. The results of pilot studies and cost-effectiveness analysis indicated that Scheme B is effective, rational and economic, and can be implemented to replace the routine surveillance measures in areas where malaria has been at the late consolidation phase in China.
Subject(s)
Adult , Animals , Anopheles , Antimalarials/therapeutic use , Child , China/epidemiology , Cost-Benefit Analysis , Disease Notification/economics , Humans , Longitudinal Studies , Malaria, Falciparum/economics , Malaria, Vivax/economics , Mass Screening/economics , Mosquito Control/economics , Outcome and Process Assessment, Health Care , Pilot Projects , Population SurveillanceABSTRACT
Electrophoretic studies were carried out on isozymes of 3 populations of Anopheles minimus collected from Guangxi and Yunnan Provinces of the People's Republic of China in 1993. Eight proteins were analyzed by 5% polyacrylamide gel electrophoresis. The most variable population, Y-F, was highly polymorphic at 14 of 20 loci (P=0.700) with an average heterozygosity H of 0.340. P values of 0.500 and 0.700, and H values of 0.220 and 0.210 were obtained for each from 'Guangxi-Lab' (GX-L) and 'Yunnan-Lab' (Y-L), respectively. Nei's genetic distances (D) between Y-L and GX-L, Y-F and GX-L, and Y-F and Y-L were 0.1131, 0.1946 and 0.1069, respectively. These results suggest that GX-L is distant from the 2 other populations, Y-L and Y-F, and that this genetic differentiation between the 2 populations of Yunnan and Guangxi Provinces corresponds to the forms A and B, which were morphologically classified by Xu et al (unpublished).
Subject(s)
Alleles , Animals , Anopheles/genetics , China , Electrophoresis, Polyacrylamide Gel , Genetic Variation , Insect Proteins/geneticsABSTRACT
Malaria is one of the major parasitic diseases in China. During the past 40 years, large scale malaria control activities were conducted in the country relying on primary health care nets and community participation. The control of malaria was implemented according to the principles of adopting integrated measures and repeated practices which are characterized by time- and locality-oriented approaches. As a result, remarkable success has been achieved. By the end of 1990, there were 117,000 malaria cases in China, with a morbidity of 0.0106%, which dropped by 95% in comparison with that in the 1950s. Most of the original hyper-endemic areas became meso- or hypo-endemic and for most of the previously meso- or hypo-endemic areas, the disease became sporadic. Malaria distribution and epidemic patterns also demonstrated great changes. The major experience comprises the integration of the malaria control program into the overall national health program, the mobilization of various sectors, including the community, the investigators and technical personnel in research institutions and control services to participate and cooperate in solving problems and difficulties encountered.