Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, United States of America.
PLoS One. 2013 Aug 6;8(8):e70972. doi: 10.1371/journal.pone.0070972. Print 2013.
Case detection and treatment are critical to malaria control and elimination as infected individuals who do not seek medical care can serve as persistent reservoirs for transmission.
Household malaria surveys were conducted in two study areas within Southern Province, Zambia in 2007 and 2008. Cross-sectional surveys were conducted approximately five times throughout the year in each of the two study areas. During study visits, adults and caretakers of children were administered a questionnaire and a blood sample was obtained for a rapid diagnostic test (RDT) for malaria. These data were used to estimate the proportions of individuals with malaria potentially identified through passive case detection at health care facilities and those potentially identified through reactive case finding. Simulations were performed to extrapolate data from sampled to non-sampled households. Radii of increasing size surrounding households with an index case were examined to determine the proportion of households with an infected individual that would be identified through reactive case detection.
In the 2007 high transmission setting, with a parasite prevalence of 23%, screening neighboring households within 500 meters of an index case could have identified 89% of all households with an RDT positive resident and 90% of all RDT positive individuals. In the 2008 low transmission setting, with a parasite prevalence of 8%, screening neighboring households within 500 meters of a household with an index case could have identified 77% of all households with an RDT positive resident and 76% of all RDT positive individuals.
Testing and treating individuals residing within a defined radius from an index case has the potential to be an effective strategy to identify and treat a large proportion of infected individuals who do not seek medical care, although the efficiency of this strategy is likely to decrease with declining parasite prevalence.
病例发现和治疗对于疟疾的控制和消除至关重要，因为未寻求医疗的感染者可能成为持续传播的源头。
2007 年和 2008 年，在赞比亚南部省的两个研究地区进行了家庭疟疾调查。在这两个研究地区，每年大约进行五次横断面调查。在研究访问期间，对成年人和儿童看护人进行了问卷调查，并采集了血样进行快速诊断检测（RDT）以检测疟疾。这些数据用于估计通过医疗机构的被动病例发现和通过主动病例发现可能发现的疟疾患者的比例。进行了模拟以从抽样家庭推断非抽样家庭的数据。检查了围绕有索引病例的家庭的半径不断增大的范围，以确定通过主动病例发现发现感染个体的家庭比例。
在 2007 年高传播环境中，寄生虫患病率为 23%，对索引病例 500 米范围内的相邻家庭进行筛查，可发现所有 RDT 阳性居民家庭的 89%和所有 RDT 阳性个体的 90%。在 2008 年低传播环境中，寄生虫患病率为 8%，对索引病例所在家庭 500 米范围内的相邻家庭进行筛查，可发现所有 RDT 阳性居民家庭的 77%和所有 RDT 阳性个体的 76%。
对居住在索引病例定义半径内的个体进行检测和治疗，有可能成为识别和治疗大量未寻求医疗的感染者的有效策略，尽管这种策略的效率可能随着寄生虫患病率的降低而降低。
