As the world took a sigh of relief with news that the Ebola epidemic is under control, another virus hit the headlines. The mosquito-borne Zika virus is spreading quickly in the Americas and has been declared a global health emergency. But what is the possibility of the virus reaching Malta? Public health consultant Tanya Melillo tells Stephanie Fsadni that the chances that the virus enters Europe and Malta are low but travellers need to be cautious.

Four million people in the Americas may become infected with the mosquito-borne Zika virus, according to a statement by the World Health Organisation released last week, with pregnant women being particularly at risk. Yesterday, the WHO declared Zika a global health emergency.

Malta is not immune to mosquitoes but the types found locally are not infected with the virus, claims Tanya Melillo, the head of the Infectious Disease Prevention and Control Unit at the health directorate.

“Presently, the only way Maltese can become infected is if they travel to countries where mosquitoes have been infected with the Zika virus,” she says.

This type of virus is transmitted by two types of mosquitoes: Aedes aegypti and aedes aldopictus.

“In the past, the Aedes aegypti mosquito was documented to be found sporadically in the Mediterranean but then disappeared for reasons unknown,” explains Melillo. “And the aedes aldopictus, which is present on our shores, does not carry the Zika virus.

“Surveillance on vector-borne diseases is ongoing. Up till now this mosquito has not been infected with any virus and has not transmitted any infections locally.”

As part of precautionary measures, all doctors in Malta have been informed about the disease. Leaflets on how to avoid being bitten by mosquitoes have been prepared and information released to the public.

Melillo stresses that unlike Ebola, the Zika virus is not transmitted by human-to- human contact. Measures are thus not necessary at the airport since someone who is bitten from abroad will not transmit the disease to others. Travellers, however, are warned to take a number of precautions if they are visiting certain countries (see list in box). These include wearing loose fitting clothes, using specific mosquito repellents and sleeping under a mosquito net.

Unlike Ebola, the Zika virus is not transmitted by human-to-human contact

Symptoms of the virus include fever, rash, joint pain or conjunctivitis (red eyes), muscle pain and headache. The illness is usually mild with symptoms lasting from a few days to a week. If a traveller shows any such symptoms within three weeks from returning from an affected area, he or she should contact a general practitioner.

Melillo, however, emphasises that pregnant women should postpone travelling to such countries and one should take precautions to “avoid getting pregnant while in these countries”.

“While the symptoms of the Zika virus are mild and self-limiting, the major concern presently is that there seems to be evidence that is suggesting that pregnant women being infected with the virus is resulting in their unborn child developing microcephaly – a small head with potential brain damage.”

There is currently no vaccine or treatment for Zika, which is a close cousin of dengue and chikungunya, but companies and scientists are racing to create a vaccine.

A municipal health worker fumigatinga street as part of efforts to prevent the spread of the Zika virus in Tegucigalpa, Honduras. Photo: Jorge Cabrera/Reuters

The latest data shows that more than 2,100 pregnant Colombian women are currently infected with the virus but officials expect the number to escalate to 700,000 cases. But the country hit hardest by the disease is Brazil. It has been reported that around 3,700 cases of microcephaly are strongly suspected to be related to Zika.

The WHO, which was stung by criticism that it reacted too slowly to West Africa’s Ebola epidemic which killed more than 10,000 people, yesterday convened a committee in Geneva to ascertain whether the outbreak constitutes a public health emergency of international concern.

“WHO is concerned about the causal linkage between pregnant women who are contracting the virus and the effect it may have on their unborn child,” says Melillo.

“Irrespective of whether WHO declares this an international emergency or not, the public, women especially, need to be informed about the risk of getting this infection while pregnant due to the possible serious consequences to the unborn child. This can only be done through avoidance of getting bitten by infected mosquitoes.”

Anyone having queries can contact the Infectious Disease Prevention and Control Unit helpline on 2132 4086.

Travel with caution

Local travellers to any country affected by the Zika virus – Barbados, Bolivia, Brazil, Cape Verde, Colombia, Dominican Republic, Ecuador, El Salvador, Fiji, French Guiana, Guadeloupe, Guatemala, Guyana, Haiti, Honduras, Maldives, Martinique, Mexico, New Caledonia, Panama, Paraguay, Puerto Rico, Saint Martin, Samoa, Solomon Islands, Suriname, Thailand, Venezuela and US Virgin Islands – are advised to take precautions to avoid getting bitten by mosquitoes. Precautions include:

• Wear loose fitting clothes with long sleeves and long trousers to cover yourself up during the day. The mosquitoes tend to be most active and bite between sunrise and sunset.

• Clothing can be treated with an insecticide like permethrin which kills insects.

• Use mosquito repellents on exposed skin areas. Repellents should contain a 40 to 50 per cent concentration of the active ingredient Deet. This insecticide cannot be used on infants aged less than three months. Repellents need to be applied at regular intervals.

• Travellers staying in accommodation without screening should sleep under a mosquito net impregnated with permethrin to avoid being bitten at night.

• Pregnant women should postpone their travels to countries that are experiencing transmission of Zika virus. Women should avoid getting pregnant while travelling to such countries.

• If you experience any virus symptoms such as fever, rash, joint pain or conjunctivitis (red eyes), muscle pain and headache three weeks after your return from an affected country, contact your GP.