Warnings are being issued to keep away from southern and eastern Thailand forests after finding populations of monkeys suffering from malaria.

The warning from the Disease Control Department in Bangkok comes after human infections surged by 10 times the usual number, with interactions with primates understood to be the leading cause.

A total of 70 cases of Plasmodium Knowlesi Malaria were reported between last October and the end of March, compared to only 10 cases in the entire year before.

Dr. Opart Karnkawinpong from the Disease Control Department said that health professionals are yet to determine whether the deadly parasite — which causes fever, chills and loss of appetite among other symptoms — can be spread from human to human.

Known carriers include crab-eating macaques, pig-tailed macaques, stump-tailed macaques, Rhesus macaques, and Assamese macaques.

Individuals who experience any symptoms and have a history of touching the monkeys in the southern provinces of Ranong and Songkhla and the eastern province of Trat have been advised to seek immediate medical attention.

At-risk people, including tourists, workers and people living in the forest, have also been asked to take preventative action against mosquito bites by wearing tight clothing, applying mosquito repellent and sleeping under mosquito nets.