The Health Ministry wants Malaysians planning to visit countries affected by outbreaks of the Zika virus, to take precautions to reduce the risk of infection.

Health director-general Dr Noor Hisham Abdullah said pregnant women, especially in the first trimester, are also advised to defer travel to Brazil until the actual cause of the surfacing of microcephaly linked to the Zika virus in that country was determined.

Microcephaly is abnormal smallness of the head, a congenital condition associated with incomplete brain development.

"The Brazilian Health Ministry is carrying out further investigations on the actual cause for the increase in microcephaly cases in childbirths including the possibility there might be a link to Zika virus infection," he said in a statement in Kuala Lumpur today.

World Health Organisation (WHO) has noted that until the middle of this month, 17 countries in the Americas had reported Zika virus cases.

They are Brazil, Barbados, Colombia, Ecuador, El Salvador, French Guyana, Guatemala, Guyana, Haiti, Honduras, Martinique, Mexico, Puerto Rico, Paraguay, Surinam and Venezuela.

The Zika virus is spread to humans through the bites of the Aedes mosquito, the same vector that causes dengue fever. The symptoms are similar to dengue - like high fever, muscle ache, joint pains, headaches, pain in the rear of the eye, conjuctivitis and rashes.

"For now, there is no vaccine to prevent infection of the Zika virus and no specific medicine to treat the disease. Treatment given is to mitigate the symptoms," said Dr Noor Hisham.

He said the precautions needed to be taken were the same as for dengue, including avoiding being bitten by the mosquito by wearing long-sleeved shirts and staying away from outdoor activities a few hours before dusk and after dawn.

Anyone experiencing the symptoms while in the countries stated or after returning to Malaysia are urged to get treatment from the nearest clinic or hospital.

- Bernama