Spread of multidrug-resistant Plasmodium falciparum malaria and predictors of treatment failures in Vietnam

Abstract

Background Drug-resistant falciparum malaria is an increasing public health burden. We examined the magnitude of Plasmodium falciparum infection and the patterns and predictors of treatment failure in Vietnam.Methods Medical records of all 443 patients with malaria infection admitted to the Hospital for Tropical Diseases between January 2015 and December 2018 were used to extract information on demographics, risk factors, symptoms, laboratory tests, treatment, and outcome. ResultsMore than half (59.8%, 95%CI 55.1%-64.4%) of patient acquired P. falciparum infection of whom 21.9% (95%CI 17.1%-27.4%) had severe malaria, while 10.2% (95%CI 6.8%-14.5%) and 19.2% (95%CI 14.7%-24.5%) developed early treatment failure (ETF) and late treatment failure (LTF) respectively. ETF was 6.8% among patients referred from Binh Phuoc province and Central Highland, 11.3% from other areas in Vietnam, and 6.9% from Africa. LTF was 16.2% among patients from Binh Phuoc province and Central Highland, 22.6% from other areas in Vietnam, and 27.6% from Africa.Most patients (98.5%) recovered completely. Having severe malaria was a predictor of ETF (AOR 4.42, 95%CI 1.85-10.61, P = 0.001). No predictor of LTF was identified.Conclusion P. falciparum remains the prevalent malaria parasite. Despite low mortality rate, severe malaria is not rare and is a significant predictor of ETF. Parenteral artesunate and an oral partner drug should be concurrently used for severe malaria to reduce the risk for ETF. The study alerts the possibility of drug-resistant malaria in Africa and other areas in Vietnam which are known as nonendemic areas of antimalarial drug resistance. A more comprehensive study using molecular technique in these regions is required to completely understand the magnitude of drug-resistant malaria and to design appropriate control strategies.