Sleigh A C, Liu X L, Jackson S, Li P, Shang L Y
Australian Centre for International and Tropical Health and Nutrition, University of Queensland, Herston.
Bull World Health Organ. 1998;76(3):265-70.
Henan Province (population, 90 million) in China has nonstable endemic malaria. After 1970 when 10.2 million cases of malaria were reported in the province, a huge control programme was undertaken, and in the mid-1980s indoor spraying and bednet impregnation with pyrethroids began. By 1992 only 318 cases were reported. In 1992 Henan declared "basic elimination of malaria" and in consequence spraying and bednet impregnation ceased after 1994. Subsequently, malaria broke out again in southern Henan. In 1995 we conducted a household survey for malaria transmission in southern Henan. Blood smears and serum samples for immunofluorescent antibody (IFA) testing were collected from 2329 people and 3.1% (73/2329) were positive for infection with Plasmodium vivax and 13% (301/2329) positive for malaria (titre > or = 1:20). All age groups were affected. Exophilic Anopheles sinensis occurs throughout the province; endo-anthropophilic A. anthropophagus, whose vectorial capacity is 20 times greater than that of A. sinensis, occurs mainly in southern Henan (S of latitude 33 degrees N) and was greatly reduced in numbers during 1985-92. Comparison of 1995 entomological data with historical data showed that A. anthropophagus increased in proportion to other anophelines after spraying activities and impregnation of bednets ceased. Over 10% of 9377 residents reported having malaria. The true number affected among the at-risk population of 700,000 must be larger. We conclude that impregnated bednets and malaria surveillance should continue even after an area is declared to have "basically eliminated" malaria.
中国河南省（人口9000万）存在不稳定的地方性疟疾。1970年该省报告了1020万例疟疾病例后，开展了一项大规模防治计划，20世纪80年代中期开始使用拟除虫菊酯进行室内喷洒和蚊帐浸泡处理。到1992年，仅报告了318例病例。1992年河南宣布“基本消灭疟疾”，因此1994年后停止了喷洒和蚊帐浸泡处理。随后，河南南部疟疾再次爆发。1995年，我们在河南南部开展了一项关于疟疾传播的家庭调查。从2329人中采集了血涂片和用于免疫荧光抗体（IFA）检测的血清样本，3.1%（73/2329）的人感染间日疟原虫呈阳性，13%（301/2329）的人疟疾检测呈阳性（滴度≥1:20）。所有年龄组均受影响。嗜人按蚊全省均有分布；嗜人按蚊的媒介能量比中华按蚊大20倍，主要分布在河南南部（北纬33度以南），在1985 - 1992年期间数量大幅减少。将1995年的昆虫学数据与历史数据进行比较发现，停止喷洒活动和蚊帐浸泡处理后，嗜人按蚊在按蚊中的比例增加。9377名居民中超过10%报告曾患疟疾。在70万高危人群中实际受影响的人数肯定更多。我们得出结论，即使一个地区宣布“基本消灭”疟疾后，也应继续使用浸泡蚊帐并开展疟疾监测。
