African malaria threat

Malaria imported from African continent has been increasing steadily in the last few years, and is posing unnoticed public health threat to Nepal

On February 5, 2018, a 30-year-old male, who returned from Lubumbashi of Democratic Republic of the Congo visited our hospital after he was diagnosed with and treated for plasmodium falciparum malaria in a private hospital in Kathmandu. According to the patient, he developed high-grade fever with chills and rigors on the fourth day after his arrival from Congo. He was unconscious following several episodes of vomiting for three days after onset of fever. His three other friends (who worked together in Lubumbashi) were also treated for severe malaria and recovered uneventfully. According to the patient, a year ago, one of his colleagues (in Lubumbashi) died of acute renal failure due to complication of severe malaria. It shows that African malaria is becoming an increasing new challenge for Nepal, which aims to become “malaria-free country” by 2026.

Malaria is a parasite disease that is transmitted through the bite of an infected female anopheles mosquito. There are five different species of human malaria and they are known as Plasmodium vivax (P vivax), Plasmodium falciparum (P falciparum), Plasmodium ovale (P ovale), Plasmodium malariae (P malariae), and Plasmodium knowlesi (P knowlesi). According to the 2017 annual report published by Department of Health Services, P vivax was the most common species of malaria followed by P falciparum in Nepal. No cases of P ovale, P malariae and P knowlesi have been reported in the published report. It could be due to rapid diagnostic test kit, which is widely available and used for suspected malaria patients but detects only P falciparum and P vivax malaria. As a result, other types of malaria might have gone unnoticed or even misdiagnosed with other infectious diseases. Microscopic technique allows the examiners to differentiate the types of malaria and its stages. But, unfortunately, nowadays rapid diagnostic tests for malaria is preferred choice over microscopic testing among examiners and lab technicians in almost all hospitals or health centers. P falciparum is considered as the most severe and fatal malaria among malaria species. It infects central nervous system and is characterized by coma and is frequently fatal, if left untreated. It is also known as “cerebral malaria.” P falciparum is the most common cause of human malaria across the African continent, while P vivax is the most widespread human malaria when compared to Pfalciparum in Nepal. Thus, if patients who lived in or visited African countries and developed signs and symptoms compatible with malaria disease they should consider it seriously and seek treatment as quickly as possible before the complications appear.

High-grade fever associated with chills and rigors followed by sweating are the classical symptoms of malaria. Usually, fever appears in every two days with the parasites P falciparum, P vivax and P ovale, while fever occurs every three days with the parasite P malariae. However, fever appears in every 24 hours with the parasite P knowlesi. Symptoms start usually 10 to 15 days after the infection. Headaches, vomiting, nausea, body-ache, general malaise including spleen and liver enlargement are other associated signs and symptoms of malaria.

Malaria is treated with specific treatment. According to the national treatment protocol, chloroquine, primaquine and artemisinin-based combination (Coartem) therapy are currently in use for treating malaria. Chloroquine and primaquine are used to treat Pvivax and Povale, while Coartem is used for for P falciparum. There is little information about drug resistant malaria in Nepal. However, a growing number of studies show that Coartem resistant P falciparum is emerging in Africa. Thus, migrant workers who are residing or working in African countries or returning Nepal after infection with a P falciparum infection may pose a unique challenge while treating in Nepal. Moreover, introduction of such Coartem resistant P falciparum in Nepal could become an obstacle to achieve malaria-free Nepal by the year 2026.

So far, no separate guideline is available for the management of imported malaria in Nepal. Annual report showed increasing trend of imported malaria in Nepal. Treatment for malaria imported from India is similar to Nepal probably due to their similar genetic makeup. However, studies have shown significant differences in genetic makeup of malaria species between Africa and Southeast region and even perhaps there is little or no immunity to African malaria species in the Nepali population. Nowadays, more and more migrant workers are opting to go to African countries for better employment. Given this, time has come to develop a separate treatment guidelines so that local health-care providers can make a quick and accurate treatment while treating those who returned from African continent. For this, physicians must be motivated to participate in continuing medicine education (CME) to maintain and improve their clinical performance as well as to update on recent progress in malaria research.

Imported malaria, particularly from African continent, has been increasing steadily in the last few years, and is posing unnoticed public health threat to Nepal. Therefore, a separate malaria treatment guideline is needed to address imported African malaria to achieve the 2026 malaria elimination goal.

The author is Chief of the Clinical Research Unit at Sukraraj Tropical and Infectious Disease Hospital, Teku