Vector-related case-control study of severe malaria in Kilifi District, Kenya

Charles N M Mbogo, Ephantus W. Kabiru, Gregory E. Glass, Dayo Forster, Robert W. Snow, Canute P M Khamala, John H. Ouma, John I. Githure, Kevin Marsh, John C Beier

Research output: Contribution to journalArticle

18 Citations (Scopus)

Abstract

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 = 0.9). Both the overall abundance of anopheline mosquitoes (odds ratio [OR] = 1.5) and P. falciparum sporozoite rates (OR = 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.

Original languageEnglish
Pages (from-to)781-785
Number of pages5
JournalAmerican Journal of Tropical Medicine and Hygiene
Volume60
Issue number5
StatePublished - May 1 1999
Externally publishedYes

Fingerprint

Kenya
Malaria
Case-Control Studies
Culicidae
Odds Ratio
Animal Husbandry
Anopheles gambiae
Sporozoites
District Hospitals
Ambulatory Care Facilities
Infection
Demography

ASJC Scopus subject areas

  • Parasitology
  • Infectious Diseases

Cite this

Mbogo, C. N. M., Kabiru, E. W., Glass, G. E., Forster, D., Snow, R. W., Khamala, C. P. M., ... Beier, J. C. (1999). Vector-related case-control study of severe malaria in Kilifi District, Kenya. American Journal of Tropical Medicine and Hygiene, 60(5), 781-785.

Vector-related case-control study of severe malaria in Kilifi District, Kenya. / Mbogo, Charles N M; Kabiru, Ephantus W.; Glass, Gregory E.; Forster, Dayo; Snow, Robert W.; Khamala, Canute P M; Ouma, John H.; Githure, John I.; Marsh, Kevin; Beier, John C.

In: American Journal of Tropical Medicine and Hygiene, Vol. 60, No. 5, 01.05.1999, p. 781-785.

Research output: Contribution to journalArticle

Mbogo, CNM, Kabiru, EW, Glass, GE, Forster, D, Snow, RW, Khamala, CPM, Ouma, JH, Githure, JI, Marsh, K & Beier, JC 1999, 'Vector-related case-control study of severe malaria in Kilifi District, Kenya', American Journal of Tropical Medicine and Hygiene, vol. 60, no. 5, pp. 781-785.
Mbogo CNM, Kabiru EW, Glass GE, Forster D, Snow RW, Khamala CPM et al. Vector-related case-control study of severe malaria in Kilifi District, Kenya. American Journal of Tropical Medicine and Hygiene. 1999 May 1;60(5):781-785.
Mbogo, Charles N M ; Kabiru, Ephantus W. ; Glass, Gregory E. ; Forster, Dayo ; Snow, Robert W. ; Khamala, Canute P M ; Ouma, John H. ; Githure, John I. ; Marsh, Kevin ; Beier, John C. / Vector-related case-control study of severe malaria in Kilifi District, Kenya. In: American Journal of Tropical Medicine and Hygiene. 1999 ; Vol. 60, No. 5. pp. 781-785.
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