Distribution of long-lasting
insecticide-treated nets (LLINs), passive detection and treatment with
artemisinin-based combination
therapy (ACT), and intermittent preventive treatment in pregnancy (IPTp) are the mainstay
malaria control measures of Guinea-Bissau's national control programme. This study aimed to estimate the prevalence of Plasmodium falciparum on Bubaque, the most populous island of the country's remote Bijagos archipelago. A cross-sectional survey was performed at the start of the rainy season in August 2017. Participants were recruited using systematic random sampling in a two-stage stratified cluster design.
Malaria parasitemia was detected using rapid diagnostic tests (RDTs) and quantitative PCR (qPCR). Data on housing, education, larval source management, socioeconomic status,
anemia, and
malaria preventive measures were collected. Multivariable logistic regression models were constructed to identify associations with P. falciparum
infection. Four hundred four persons (aged 6 months-79 years, median 17 years) were enrolled in the study. The prevalence of P. falciparum
parasitemia was 5.8% by RDT (95% CI: 3.55-9.33) and 16.9% by qPCR (95% CI: 13.09-21.71). The prevalence of
anemia was 74.3% (95% CI: 69.04-78.85) as defined by the WHO criteria. All sampled houses were found to have open eaves; 99.5% of the surveyed population reported sleeping under a bednet (95% CI: 97.8-99.9). Although reported LLIN use is high, there remains an appreciable prevalence of
malaria, suggesting that transmission is ongoing and further tools are required to reduce the burden of the disease.