Cases of the ‘Monkey malaria’, Plasmodium knowlesi, up in Malaysia
Health officials in Malaysia are showing concern over the increases in cases of the “Monkey malaria”, Plasmodium knowlesi in humans in recent years, according to a Sun Daily report today.
Universiti Malaya department of parasitology consultant, Datin Dr Indra Vythilingam, said the number of cases had increased significantly since 2004.
“We have seen a lot of people with monkey malaria,” she told the Sun today.
Although Plasmodium knowlesi, often considered the fifth human malaria species (along with P. falciparum, P. vivax, P. malariae and P. ovale) as it has been seen in humans, it is still mostly known as a malaria of macaques in southeast Asia where 78% of the monkeys tested were positive. In 2011, in a paper published in the journal PloS Pathogens, researchers from Malaysia and London warn that that this species of malaria, most frequently seen in macaques could eventually target humans.
Researchers at the time were concerned about this huge reservoir of P. knowlesi in the monkeys and the increasing human populations and deforestation.
The Sun Daily reports that in 1992, the parasite only accounted for 1% of reported malarial infections in Malaysia, but cases had increased to 35% in 2011.
Simian malaria
Image/CDC
Malaysian health authorities are taking measures to get the monkey malaria under control. These measures include setting up a surveillance system, an integrated vector management system, early detection and prompt treatment, preparedness and outbreak response, capacity-building and operational research.
Plasmodium knowlesi is mostly found is mostly found in South East Asian countries particularly in Borneo, Malaysia, Myanmar, the Philippines, Singapore, and Thailand.
Plasmodium knowlesi is absent in Africa. This may be because there are no long-tailed and pig-tailed macaques (the reservoir hosts of P. knowlesi) in Africa and many West Africans lack the Duffy antigen – a protein on the surface of the red blood cell that the parasite to uses to invade.
Mosquitoes belonging to the Anopheles leucosphyrus group are known to transmit P. knowlesi from monkeys to humans.
In addition to P. knowlesi, Malaysian health authorities are also battling another mosquito borne infectious disease, dengue fever. The Malaysian Ministry of Health’s latest data shows that from January to February 22, 2014 , the cumulative number of patients with dengue reported throughout the country is 16,383 , an increase of as much as 316 % or 12,446 cases versus the 3,937 cases reported for the same period last year (computer translated).
For more infectious disease news and information, visit and “like” the Infectious Disease News Facebook page and the Outbreak News This Week Radio Show page.
Looking for a job in health care? Check here to see what’s available
