Vector-related case-control study of severe malaria in Kilifi District, Kenya
Date
1999Author
Mbogo, Charles NM
Kabiru, EW
Glass, GE
Forster, D
Snow, RW
Khamala, CPM
Ouma, JH
Githure, JI
Marsh, K
Beier, JC
Type
ArticleLanguage
enMetadata
Show full item recordAbstract
A case-control study examined vector-related and environmental parameters associated with severe
malaria in Kilifi District along the coast of Kenya. Over an 11-month period, 119 children identified with severe
malaria infections at the Kilifi District Hospital were matched by age with control children who reported to the
outpatient clinic with nonsevere infections. Intensive mosquito sampling was done in each of the case-control houses
over a four-day period, beginning within a week of index case admission. A total of 109 environmental, demographic,
behavioral, and animal husbandry variables were characterized for each household. Vector species (Anopheles gambiae
s.l. and An. funestus) were detected in 40.1% and 36.1% of case and control houses, respectively. The relative
abundance of vectors in individual houses was stable over the two-week resampling periods (r 5 0.9). Both the
overall abundance of anopheline mosquitoes (odds ratio [OR] 5 1.5) and P. falciparum sporozoite rates (OR 5 1.5)
were not significantly different between case and control houses. In a matched analysis, 11 of 109 house variables
associated significantly with severe malaria were also associated with vector abundance, as determined by chi-square
linear trend analysis. Under conditions of year-round, low-level transmission on the coast of Kenya, the risk of severe
disease in children is multifactorial and not governed strictly by transmission intensity or environmental heterogeneity
affecting vector abundance and distributions. This suggests that current interventions that appear to be achievable
only in areas where transmission is already low to moderate should be appropriate. However, such interventions
should be monitored so that inappropriate and possibly disastrous control activities can be avoided in Africa.
URI
http://erepository.uonbi.ac.ke:8080/xmlui/handle/123456789/33371http://www.ncbi.nlm.nih.gov/pubmed/10344652
Citation
Am. J. Trop. Med. Hyg., 60(5), 1999, pp. 781–785Publisher
Department of Zoology, University of Nairobi, Kenya Medical Research Institute (KEMRI), Kilifi Research Unit, Kilifi, Kenya Department of Tropical Medicine, Tulane University, New Orleans, Louisiana Division of Vector Borne Diseases, Ministry of Health, Nairobi, Kenya