New Article Highlights Continued Success of Bioko Island Malaria Control Project
On February 5, Malaria Journal published "Trends in parasite prevalence following 13 years of malaria interventions on Bioko island, Equatorial Guinea: 2004–2016," written by Jackie Cook of the London School of Hygiene and Tropical Medicine based on survey data from the Bioko Island Malaria Control Project (BIMCP). It is co-authored by MCDI affiliates Dianna Hergott, Wonder Phiri, Luis Segura, Guillermo Garcia and Chris Schwabe. The article concludes that the combination of island-wide bed net distribution and indoor residual spraying of homes conducted by the BIMCP the have resulted in a substantial reduction in malaria transmission on Bioko Island, with parasite prevalence reducing from 43.3% in 2004 to 10.5% in 2016.
The BIMCP, funded by the Government of Equatorial Guinea and a consortium of oil companies led by Marathon Oil, began in 2003 as an effort to reduce the heavy burden of malaria on the population of Bioko Island. MCDI, as the implementing agency of this project, has worked to implement a comprehensive set of malaria control interventions, including the distribution long-lasting insecticide treated net distribution and indoor residual spraying of insecticide in homes focused on in the study. In addition, the BIMCP works to prevent malaria in pregnancy, enhance health workers’ capacities to diagnose and treat malaria, as well as support for behavior change communication and social mobilization efforts to prevent malaria.
MCDI has conducted Malaria Indicator Surveys (MIS) every year beginning in 2004, which are the basis for Cook's study. Rapid diagnostic tests are used to assess parasitemia amongst the population, with over 106,500 individual tests conducted between 2004 and 2016. The annual MIS also includes testing for anemia in children and a questionnaire assessing other malaria-related indicators. Based on the results of these surveys, Cook found that in addition to the reduction in parasite prevalence, the prevalence of moderate to severe anemia in children (1-5 years old) reduced from 14.9 to 1.6% from 2004 to 2016.
In addition to these promising results outlined in Cook's article, previous studies have shown that the BIMCP has been able to reduce transmission in children 2 to 14 years old by nearly 76%, and all-cause mortality among children under five years old has reduced by 64%. There has also been a 98% reduction in the entomological inoculation rate since 2004, i.e. the number of infective bites per person per year.
Cook's study specifically demonstrates the effectiveness of net distribution and indoor residual spraying in reducing malaria transmission, especially over a sustained period of time with rigorous surveillance. The BIMCP continues to implement its comprehensive efforts throughout Bioko Island, and in collaboration with the Equatoguinean Malaria Vaccine Initiative (EGMVI), aims to eventually eliminate malaria from Bioko Island.