Malaria screening program for children unsuccessful

A school-based malaria screening and treatment program provided no health benefits for children living in an area of low to moderate malaria transmission, according to new study results. The program also appeared to have a negative effect on some schoolchildren’s academic performance.

“School-based malaria control is increasingly recognized as an important potential component for integrated school health packages,” researchers wrote in PLoS Medicine. “However, as yet there is no consensus about the most effective malaria interventions for the alternative transmission settings.”

Katherine E. Halliday, a researcher at the London School of Hygiene and Tropical Medicine, and colleagues performed a cluster randomized trial between 2010 and 2012 to investigate the effect of an intermittent malaria screening and treatment (IST) program on the health and education of 5,233 children and young adults enrolled in 101 government primary schools located on the south coast of Kenya. The intervention, which included screening by public health workers using rapid diagnostic tests (RDTs) and treatment with a six-dose regimen of artemether-lumefantrine (Coartem, Novartis), was delivered at randomly selected schools. Children were followed for 24 months and assessed for anemia and parasitemia, as well as for sustained attention in the classroom and academic performance.

During the 2-year study period, an average of 88.3% of children in the intervention arm were screened for malaria, of whom 17.5% were positive for infection.

However, the researchers observed no differences in the prevalence of anemia at 12 (adjusted RR=1.03; 95% CI, 0.93-1.13) or 24 months (adjusted RR=1; 95% CI, 0.9-1.11) between children who did and did not receive the intervention, nor was there any effect on the prevalence of Plasmodium falciparum infection and on children’s ability to stay focused in the classroom.

In addition, the intervention appeared to have a negative effect on the spelling and arithmetic scores of younger children included in the study. The researchers said this may be due to a combination of factors, including some children’s apprehension of the IST program — specifically, the finger prick to screen for infection.

Implications for future interventions

According to Halliday and colleagues, there are several explanations why the intervention failed to have a positive health effect, including the possibility of high rates of reinfection and acquisition between screenings and variability in the performance of RDTs. The researchers said they are currently investigating the diagnostic performance of RDTs, as well as the influence of individual and local transmission of malaria and seasonal factors on the study results.

“Nevertheless, our results do highlight a potential role for schools as screening platforms,” the researchers said. “School screenings using RDTs could provide an operationally efficient method to initially identify transmission hotspots for targeted community control.”

In an accompanying editorial, Lorenz von Seidlein, MD, PhD, of the global and tropical health division of Menzies School of Health Research in Australia, said the findings were “overwhelmingly disappointing,” but they cannot be attributed to any methodological shortcomings in the study.

“It is easy to criticize retrospectively the failure of well-intentioned interventions and infinitely harder to predict success …” he wrote.

Von Seidlein said successful malaria elimination strategies may require treating targeted populations regardless of symptoms or test results.

“… After other approaches have failed, perhaps an evaluation of strategies based on presumptive treatment of targeted populations should now have the highest priority?” he wrote.

Katherine E. Halliday can be reached at katherine.halliday@lshtm.ac.uk.

For more information:

Halliday KE. PLoS Med. 2014;doi:10.1371/journal.pmed.1001594.

von Seidlein L. PLoS Med. 2014;doi:10.1371/journal.pmed.1001595.

Disclosure: The researchers report no relevant financial disclosures.