Male farmers at high risk of contracting 'monkey malaria'

Beware! A study has found that in Malaysia, adult male farmers, involved in plantation, clearing vegetation and forestry work were four times more likely to contract monkey malaria.

Plasmodium knowlesi is a zoonotic malaria parasite, which is common in forest-dwelling macaque monkeys and gets transmitted between hosts, by mosquitoes.

It has a rapid growth rate in the blood that can lead to high levels of parasites in a short time, causing severe and fatal disease.

Researchers from London School of Hygiene & Tropical Medicine found that farmers in the country's Sabah region, who work on plantations, clearing vegetation and taking part in forestry work were affected the most.

This study is the first comprehensive assessment of factors associated with contracting symptomatic P. knowlesi infection, which has threatening efforts to eliminate malaria in South East Asia.

The team analysed 1,000 people in the Sabah districts of Kudat and Kota Marudu.

Individuals, with P. knowlesi, were compared with individuals with other types of human malaria and a control group without malaria.

Detailed questionnaires collected information on the basis of daily activities, residence and the frequency with which participants saw monkeys.

The findings indicated that men were four times more likely to have P. knowlesi infection than women.

Principal collaborator on the study Chris said that P. knowlesi is a complex and potentially life threatening parasite. The rise in cases not only threatens the great gains Malaysia has made towards eradicating malaria, but is of concern for other countries in South East Asia.

The findings suggested that humans, working on the fringes of the forest, are at risk of contracting P. knowlesi, as well as in the forest itself when they carry out activities such as hunting.

Lead study author Dr Matthew Grigg, Menzies said that the research indicated that adult males are most at risk of contracting this type of malaria including from activities such as farming, land clearing activities, working on palm oil plantations, and travelling or sleeping outside.

The results were published in the journal of the Lancet Planetary Health.