QUITO, May 4 (Xinhua) -- Around 400 pregnant women have been contaminated by the Zika virus in Ecuador since April 2016, the Minister of Public Health, Veronica Espinoza, said Thursday.

In a press conference, the minister said that nine other cases had been found of vertical transmission from mother to fetus, and three of birth malformations linked to the virus.

Zika is a virus transmitted by the Aedes aegypti mosquito, which is also a carrier of dengue and chikungunya.

Only around 20 percent of infected adults will even show symptoms but it is dangerous for pregnant women as the virus can be transmitted from mother to fetus, or through sexual relations or blood transfusions, said Espinoza.

It can lead to babies being born with microcephaly or a range of other malformations.

Espinoza asked the population to strengthen their efforts to protect pregnant women from contracting the virus.

The Ministry has led a campaign against the mosquitoes across the country by spraying chemicals, destruction of areas in which mosquitos could lay eggs.