This paper describes a large scale control programme for falciparum malaria in Xinyang prefecture, China, from the early 1980s to 1992. Falciparum malaria, transmitted mainly by Anopheles anthropophagus, was epidemic in Gusi, Huangchuan, Shangcheng and Huaibin counties in the prefecture in the early 1980s, 2922 cases being reported in 1984. From 1985 to 1992, DDT residual spraying and the use of bed nets impregnated with pyrethroid insecticide were introduced for 2 consecutive years in areas at higher risk of P. falciparum infection, and then gradually extended to cover all the endemic areas over a period of 8 years. Malaria control was also carried out through the primary health care system in 4 counties, as had been done since the 1970s. As a result, no falciparum malaria case has been found since 1988 in spite of extensive surveillance, and vivax malaria has also decreased greatly. Repeated cross-sectional surveys showed that A. anthropophagus could not be found in most sites after 2 consecutive years of the vector control programme. Vector control was a major factor in the successful elimination of falciparum malaria and decreasing the incidence of P. vivax in the 4 counties.

A community-based intervention trial was carried out to evaluate the effectiveness of alphamethrin-impregnated bed nets for control of Plasmodium vivax malaria and its vector in an area of moderate endemicity in southern Henan province, central China in 1990. Malaria incidence was significantly lower in the intervention group than in the comparison group (2.03 vs. 3.57 per 100 person-years at risk). The protective efficacy for malaria incidence was 43%. The prevalence of malaria parasitaemia among children under 10 years old in the intervention group was about one-quarter of that in the comparison group (0.93% vs. 3.25% and 0.71% vs. 1.96% after one and 4 months use of impregnated nets, respectively). Alphamethrin-impregnated bed nets had a mass killing effect on vector mosquitoes. The outdoor person-biting density of Anopheles anthropophagus and A. sinensis decreased by 70.3% and 29.3% respectively. The density of these 2 mosquito species found resting inside treated nets was close to zero. No side effect was found among users of impregnated bed nets. Impregnation with alphamethrin was more effective on polyester than on cotton netting and residual effects lasted at least one year. Use of alphamethrin is less expensive than permethrin and deltamethrin.

Background Malaria was once a serious public health problem in China, with Plasmodium vivax the major species responsible for more than 90% of local transmission. Following significant integrated malaria control and elimination programmes, malaria burden declined, and since 2017 China has not recorded any indigenous case. To understand the historical malaria transmission patterns and epidemic characteristics in China and insights useful to guide P. vivax malaria control and elimination elsewhere, a retrospective study was carried out. Methods Historical data from a pilot study conducted in Guantang, Luyi in central China from 1971–1995, were digitized. The data included monthly numbers of reported cases, febrile cases, parasite carriage rates, the neonatal infection rate, and entomological data regarding Anopheles sinensis. Results Following 25 years of continuous integrated malaria control activities, malaria incidence in Guantang decreased from 4,333 cases per 10,000 in 1970 before integrated implementation to 0.23 cases per 10,000 in 1991, and no cases in 1992–1995. Some fluctuations in incidence were observed between 1977 and 1981. During the period parasite rates, antibody levels and the neonatal infection rate also decreased. The pattern of seasonality confirmed that P. vivax in Henan Province was primarily of the long incubation type (temperate) during non-transmission period. The findings retrospectively provide a scientific basis for the implementation of mass campaigns of liver stage hypnozoite clearance. Entomological studies indicated that An. sinensis was the only vector, and it preferred bovine to human hosts, predominantly biting and resting outdoors. Mosquito densities declined between 1971 and 1984. Conclusion The integrated malaria control approach in Guantang effectively controlled malaria and achieved elimination. Analysis of the effectiveness of the programme can provide guidance to other regions or countries with similar ecological settings aiming to move from malaria control to elimination. There is a potential challenge in the maintenance of non-transmission status owing to imported cases and the long dormancy of liver stage hypnozoites.

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Background: Malaria was once a serious public health problem in China with Plasmodium vivax the major species responsible for more than 90% of local transmission. Following significant integrated malaria control and elimination programs, malaria burden declined, and by 2017 China recorded no indigenous cases. To understand the historical malaria transmission patterns and epidemic characteristics in China and insights useful to guide P. vivax malaria control and elimination elsewhere, a retrospective study was carried out. Materials and Methods: Historical data from a pilot study conducted in Guantang, Luyi in central China from 1971-1995, were digitised. The data included monthly numbers of reported cases, febrile cases, parasite carriage rates, the neonatal infection rate, and entomological data from Anopheles sinensis. Results: Following 25 years of continuous integrated malaria control activities, malaria incidence in Guantang decreased from 4,333 cases per 10,000 in 1970 before integrated implementation to 0.23 cases per 10,000 in 1991, and no cases in 1992-1995. Some fluctuations in incidence were observed between 1977 and 1981. During the period parasite rates, antibody levels and the neonatal infection rate also decreased. The pattern of seasonality confirmed that P. vivax in Henan Province was primarily of long incubation type (temperate) during non-transmission period. The findings retrospectively provide a scientific basis for the implementation of mass campaigns of liver stage hypnozoite clearance. Entomological studies indicated that An. sinensis was the only vector, and it preferred bovine to human hosts, predominantly biting and resting outdoors. Mosquito densities declined between 1971 and 1984.Conclusion: The integrated malaria control approach in Guantang effectively controlled malaria and achieved elimination. Analysis of the effectiveness of the program can provide guidance to other regions or countries with similar ecological settings aiming to move from malaria control to elimination. There is a potential challenge in the maintenance of non-transmission status owing to imported cases and the long dormancy of liver stage hypnozoites.