Zika virus spreading: Brazilian President Rousseff declares war on Aedes aegypti mosquito

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Rio de Janeiro: President Dilma Rousseff said on Wednesday that Brazil must wage war against the Aedes aegypti mosquito that spreads the Zika virus linked to a surge in cases of a dangerous birth defect, focusing on eliminating the insect's breeding grounds.

Brazil's government had already announced it would deploy 220,000 troops for a day next month to spread awareness about the Zika virus, which has been linked to severe birth defects in thousands of infants.

The move came as Brazil's top health official acknowledged that the country was "badly losing the battle" against mosquito-borne diseases like Zika.

Since September, Brazil has registered 3700 cases of babies with microcephaly, a condition linked to Zika infection in which children are born with an abnormally small head and a brain that has not developed properly.

Spreading the Zika virus ... A female Aedes aegypti mosquito in the process of acquiring a blood meal from a human host. Credit: AP

The jump in cases has prompted a global health scare, with several countries cautioning pregnant women against travelling to the 22 nations in the Americas where the virus has been reported.

Without a Zika vaccine and with little known about the causes of microcephaly, Brazil has few options available for fighting the spread of the virus and the birth defect.

The mosquito thrives in dense tropical cities, and Rousseff called for the elimination of stagnant water spots where it lives and reproduces.

"We must wage war against the Aedes aegypti, the vector of dengue, of chikungunya and of Zika," Rousseff said through her Twitter account, referring to two other viral diseases transmitted to humans by the bite of infected mosquitoes.

Brazilian President Dilma Rousseff has declared war on the Aedes aegypti mosquito, which spreads the Zika virus.Credit: Fairfax

"While we do not have a vaccine against the Zika virus, the war must be concentrated on the elimination of breeding grounds for the mosquito," Rousseff added. "Getting rid of Zika is the responsibility of all of us."

The move comes as Brazil desperately looks to raise awareness of the virus and encourage people to combat the mosquito.

A health worker stands in the Sambadrome as he sprays insecticide to combat mosquitoes that transmit the Zika virus in Rio de Janeiro, Brazil.Credit: AP

Brazilian Health Minister Marcelo Castro on Monday promised 220,000 troops would be deployed next month to distribute educational pamphlets and help scour cities for mosquito breeding grounds.

Similar moves have been successful in the past. A huge eradication effort in the 1940s and 1950s, motivated by the spread of yellow fever also carried by Aedes aegypti, led Brazil to be declared free of the mosquito in 1958. But as the program was relaxed, the insect returned.

Army soldiers apply insect repellent as they prepare for a clean-up operation against the Aedes aegypti mosquito in Sao Paulo. Credit: AP

With Carnival celebrations just over a week away and the Olympic Games set for Rio de Janeiro in August, Brazil is poised to receive hundreds of thousands of visitors in the coming months, adding to concerns over the spread of the virus.

Birth defects

The Zika virus is strongly suspected of causing birth defects and may infect 3-4 million people in the Americas, including 1.5 million in Brazil, a World Health Organisation expert said on Thursday.

Marcos Espinal, head of communicable diseases at PAHO - the WHO's Americas arm - said a study would soon be published suggesting a correlation between Zika and microcephaly - babies born with small heads and brains - in Brazil.

"We don't know yet if this virus crosses the placenta and generates or causes microcephaly. We think it plays a role. There's no doubt about that," he told the WHO's executive board meeting in Geneva.

Reuters