Insecticide-Impregnated Bed Nets for Malaria Control: Varying Experiences from Ecuador, Colombia, and Peru Concerning Acceptability and Effectiveness

Axel Kroeger Latin American Centre for Health Studies, Liverpool School of Tropical Medicine, Latin American Centre, Institute of Tropical Medicine Daniel Carrion, Universidad Mayor de San Marcos, Liverpool, United Kingdom

Search for other papers by Axel Kroeger in
Current site
Google Scholar
PubMed
Close
,
Manuel Mancheno Latin American Centre for Health Studies, Liverpool School of Tropical Medicine, Latin American Centre, Institute of Tropical Medicine Daniel Carrion, Universidad Mayor de San Marcos, Liverpool, United Kingdom

Search for other papers by Manuel Mancheno in
Current site
Google Scholar
PubMed
Close
,
Jorge Alarcon Latin American Centre for Health Studies, Liverpool School of Tropical Medicine, Latin American Centre, Institute of Tropical Medicine Daniel Carrion, Universidad Mayor de San Marcos, Liverpool, United Kingdom

Search for other papers by Jorge Alarcon in
Current site
Google Scholar
PubMed
Close
, and
Karen Pesse Latin American Centre for Health Studies, Liverpool School of Tropical Medicine, Latin American Centre, Institute of Tropical Medicine Daniel Carrion, Universidad Mayor de San Marcos, Liverpool, United Kingdom

Search for other papers by Karen Pesse in
Current site
Google Scholar
PubMed
Close
Restricted access

Between 1991 and 1994, an intervention program with permethrin- and lambdacyhalothrin-impregnated bed nets was carried out over a period of nine months in each of five endemic, malarious areas of Ecuador, Peru, and Colombia. This program was evaluated through household surveys, blood sampling, in-depth longitudinal studies, and entomologic analysis. Eighty-four communities (including approximately 35,000 individuals) were paired according to malaria incidence, size, and coverage with bed nets and then randomly allocated to intervention and control groups. The results showed that peoples' acceptance of the measure was related to their perception of an immediate protective effect against insects. The effectiveness of the bed nets, measured as a reduction of malaria incidence in intervention communities as against control communities, showed large variations between and within the study areas. The protective efficacy varied between 0% and 70% when looking only at the postintervention differences between intervention and control groups. The average protection was 40.8% when considering a four-month incidence of clinical malaria attacks and 28.3% when considering a two-week malaria incidence. Important factors for the success of the bed net program were insect susceptibility to pyrethroids, high coverage with impregnated bed nets, high malaria incidence, good community participation, high mosquito densities when people go to bed, and a high proportion of Plasmodium falciparum. In one area, where DDT spraying in the control communities was executed, the effectiveness of bed net impregnation was slightly better than that of spraying.

Author Notes

Save