Raising the alarm that human lives are at a significant risk, scientists have found that a potentially fatal species of monkey malaria is being commonly misdiagnosed as a benign form of the disease in humans.
During a study, funded by the Wellcome Trust and the University Malaysia Sarawak, more than 1,000 samples from malaria patients were examined across Malaysia with the help of DNA-based technology.
The researchers found that more than one in four patients in Sarawak, Malaysian Borneo, were infected with Plasmodium knowlesi, a malaria parasite of macaque monkeys. The disease was more widespread in Malaysia than previously thought, they said.
Their study also revealed that such cases were most often misdiagnosed as the normally uncomplicated human malaria caused by P. malariae.
Until recently, it was thought that P. knowlesi could infect only monkeys, in particular long-tailed macaques found in the rainforests of South East Asia. However, the latest study has negated this notion.
The researchers see misdiagnosis of knowlesi malaria as P. malariae as a huge problem because even a short delay in accurate treatment may lead to the rapid onset of complications, including liver and kidney failure, and death.
"I believe that if we look at malaria infections in South East Asia more carefully, we will find that this potentially fatal type of the disease is more widespread than is currently thought," says Professors Janet Cox-Singh of the University Malaysia Sarawak.
"Given the evident severity of the illness that it causes, I would recommend that doctors treating patients with a laboratory diagnosis of P. malariae remain alert to the possibility that they may be dealing with the potentially more aggressive P. knowlesi. This would be particularly important in patients who have spent time in the forest fringe areas of South East Asia where the non-human primate host exists," the researcher added.
The study has been published in the journal Clinical Infectious Diseases