A fatal malaria caused by Plasmodium knowlesi infection in a healthy man, Betong, Yala, Thailand, April 2016

Abstract

Background: A zoonotic malaria caused by Plasmodium knowlesi is an emerging malaria in South East Asia. The disease was newly recognized and can cause severe illness. The reservoir is an old world macaques in a rain forest of Malaysia-Thailand border. Anopheles mosquito is known as a vector. We reported a first fatal case of P. knowlesi in a health man who worked in the jungle of Thailand-Malaysia border.
Methods: We interviewed the case's relatives about the clinical presentation and exposure history including reviewed medical records in the hospital. Blood smear was done and subsequently performed molecular detection by RT-PCR for P. Knowlesi. Active case finding among the case's colleagues who recently went to the jungle within a month was also done and then laboratory testing was performed by blood smear and RT-PCR.
Results: A 46 year-old healthy man developed symptom in 10 days after spending 2 weeks in the jungle at Thailand border to Malaysia. He was admitted at Betong hospital, Yala province in state of shock and comatose after admission and then intubation was done. He was renal and hepatic failures and pulmonary hemorrhage. He died within eight days after admission. Peripheral blood smear for malaria parasites indicated hyperparasitaemia and malaria antigen test revealed non P. falciparum. Then P. knowlesi infection was suspected and treated. A single species of P. knowlesi was confirmed by PCR. Ricketsia, Dengue and Leptospira of FTD Tropical Fever Core PCR were all negative. There was no additional case or laboratory confirmed among 31 colleagues who recently went to the jungle in one month ago. In Thailand, 45 cases of P. knowlesi were reported and Thailand-Malaysia border are the highest incidence.
Conclusion: Malaria caused by P. knowlesi can cause severe and dead in healthy human. Currently, there is epidemic and potentially life threatening in Malaysia. Early diagnosis and treatment with antimalarial chemotherapy is necessary to prevent multiple organ failures which leading to died. A history of jungle visiting in the epidemic area particularly Thailand-Malaysia border should be pay attention for a P. knowlesi infection. Preventing Anopheles mosquito bite in the jungle is advised for people who stay overnight in the jungle.