Appawu M, Dadzie S, Abdul H, Asmah H, Boakye D, Wilson M, Ofori-Adjei D
Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Ghana.
Ghana Med J. 2006;40(4):137-41. doi: 10.4314/gmj.v40i3.55269.
To assess the risk of transmission of viral haemorrhagic fevers in northern Ghana.
A two-year cross-sectional entomological study was carried out in four communities in the northern part of Ghana. Standard WHO methods were used to collect adult and larvae of Aedes mosquitoes to estimate man-vector contact rates and larval indices.
A total of 2804 households were surveyed to estimate larval indices and man-vector contacts of potential vectors of viral haemorrhagic fevers such as Yellow fever and Dengue. Over 56% households in each study site were positive for Aedes larvae. Relatively higher Breteaux index (BI) and Container index (CI) were estimated in Damongo (BI: 180 and CI: 44.8) and Jirapa (BI: 149.7 and CI: 41.5) compared to Tumu (BI: 76.1 and CI: 19.5) and Bolgatanga (BI: 72.4 and CI: 20.6). Man-biting rates of 9.8 and 18.5 bites /man/hour were estimated for Damongo and Jirapa respectively whilst Bolgatanga recorded 10 B/M/H. Generally, man-vector contact rates in all the study sites were higher during the dry season than the wet season. Larval indices showed seasonal variations and the dry season was identified as the high-risk period for transmission of viral haemorrhagic fevers and possible disease outbreaks. No flavivirus was detected in the 2034 Aedes mosquitoes from the study sites by RT-PCR.
Aedes mosquito larval densities and adult biting rates, in all the study areas were sufficient to promote outbreaks of viral haemorrhagic fevers.
评估加纳北部病毒性出血热的传播风险。
在加纳北部的四个社区开展了一项为期两年的横断面昆虫学研究。采用世界卫生组织的标准方法收集埃及伊蚊的成虫和幼虫，以估算人与病媒的接触率和幼虫指数。
共调查了2804户家庭，以估算病毒性出血热（如黄热病和登革热）潜在病媒的幼虫指数和人与病媒的接触情况。每个研究地点超过56%的家庭埃及伊蚊幼虫呈阳性。与图穆（布雷托指数：76.1，容器指数：19.5）和博尔加坦加（布雷托指数：72.4，容器指数：20.6）相比，达蒙戈（布雷托指数：180，容器指数：44.8）和吉拉帕（布雷托指数：149.7，容器指数：41.5）的布雷托指数（BI）和容器指数（CI）相对较高。达蒙戈和吉拉帕的人均叮咬率分别估计为9.8次/人/小时和18.5次/人/小时，而博尔加坦加记录的人均叮咬率为10次/人/小时。一般来说，所有研究地点的人与病媒接触率在旱季高于雨季。幼虫指数呈现季节性变化，旱季被确定为病毒性出血热传播和可能疾病暴发的高危期。通过逆转录聚合酶链反应，在研究地点采集的2034只埃及伊蚊中未检测到黄病毒。
所有研究区域的埃及伊蚊幼虫密度和成虫叮咬率足以促使病毒性出血热暴发。
