Taiwan reports first Plasmodium knowlesi malaria case in two decades
The Taiwan Centers for Disease Control (CDC) announced today that there was one new case of imported malaria in Taiwan. The patient is a foreign male in his 30s who traveled to Palawan Island in the Philippines in early June this year. He said he did not take malaria prevention medication and was bitten by mosquitoes while participating in natural eco-tourism activities there. He had symptoms such as headache, fever, tea-colored urine, muscle pain, and drowsiness before entering Taiwan on June 19. He went to the hospital for treatment on June 25 because his symptoms did not improve. He went to the hospital again on June 27 because of dyspnea, dizziness, and oliguria. After reporting and testing, it was confirmed that he was infected with Plasmodium knowlesi. The case is currently hospitalized for treatment, and the health authorities are continuously tracking the case's health status and subsequent test results.
The CDC said that malaria is a disease transmitted by infected mosquitoes biting humans. It can be divided into falciparum malaria, vivax malaria, ovale malaria, malaria malariae, and knowlesi malaria. Among them, knowlesi malaria is prevalent in long-tailed macaques and pig-tailed macaques in Southeast Asia. It is caused by Plasmodium knowlesi and transmitted by local malaria mosquitoes. Since 2004, the number of reported cases of human infection with Plasmodium knowlesi in Southeast Asian countries has gradually increased, including Malaysia, the Philippines, Thailand, Singapore, Vietnam, Myanmar, and Indonesia. Most people may develop symptoms within 7-30 days after being infected with malaria. The early symptoms are similar to those of influenza, mainly fever, and may also cause headaches, muscle pain, joint pain, nausea, vomiting, and fatigue. If not properly treated, intermittent or periodic chills and tremors, fever, and sweating will occur a few days after the onset of the disease. Severe cases may lead to splenomegaly, jaundice, shock, liver and kidney failure, pulmonary edema, acute encephalopathy, and coma.
Malaria series: Plasmodium malariae, P. ovale and the monkey malaria- Plasmodium knowlesi
According to CDC monitoring data, as of July 1, this year, there have been 12 imported malaria cases, the highest in the past 19 years (2007-2025). The ages of the patients ranged from 20s to 60s. The infected countries were Kenya (3 cases), Sierra Leone and Solomon Islands (2 cases each), Tanzania, Madagascar, Benin, the Philippines, and several Central African countries (1 case each). Among them, 10 cases were infected with falciparum malaria, and 1 case was infected with Plasmodium vivax and Plasmodium knowlesi. There has been no case of imported knowlesi malaria in Taiwan for 20 years. The last case was a male Taiwanese in his 60s in 2005. He was bitten by a mosquito while doing ecotourism in Palawan, Philippines. He was diagnosed with the disease after returning to Taiwan. This was the first case of imported knowlesi malaria in Taiwan. The case announced today is the second case of imported knowlesi malaria in history.
The CDC explained that the global malaria epidemic continues, with nearly 95% of cases distributed in Africa, among which Ethiopia has a severe epidemic. In Asia, the number of cases in India this year is higher than the same period last year, while the number of cases in South Korea this year is lower than the same period last year. The epidemic in the Philippines is mainly distributed in Palawan Province. The number of cases in the province increased significantly last year, with a total of nearly 9,000 cases. The epidemic continues this year. The CDC has raised the international travel epidemic advisory level of the Philippines to Level 1: Attention. All people traveling to Palawan Island in the Philippines should take anti-mosquito measures to prevent malaria infection, including wearing long-sleeved clothes and using mosquito repellent; and those who are at high risk of severe malaria or plan to stay in the local jungle area are advised to consult a domestic tourism medical clinic at least one month before travel and take malaria prevention drugs as instructed by the doctor.
The CDC once again urges people to go to malaria-endemic areas. In addition to consulting a tourism medical clinic in advance and taking malaria prevention drugs continuously and uninterruptedly as instructed by the doctor, they should also implement anti-mosquito measures during travel; if suspected symptoms occur after returning to the country, they should seek medical attention as soon as possible, and provide the doctor with information such as travel history and preventive drugs taken as a reference for diagnosis and treatment.