Health officials dismiss claims Zika virus linked to insecticide
Health officials in Brazil have dismissed claims that a larvicide could be responsible for a rise in cases of microcephaly, and not Zika virus.
A report by Argentinian doctors suggested pyriproxyfen, which is used to control the Aedes aegypti mosquito, could be associated with the deformity, which impairs foetal brain development.
The organisation, Physicians in the Crop-Sprayed Towns, said the substance had been introduced into drinking water supplies since 2014 in affected areas of Brazil. "In the area where most sick persons live, a chemical larvicide producing malformations in mosquitoes has been applied for 18 months, and then this poison (pyroproxifen) is applied by the state on drinking water used by the affected population," the report said.
In response, the local government in Rio Grande do Sul, a state in the south of Brazil, suspended the use of pyriproxyfen.
However, the federal government was quick to dismiss the fears in a statement.
It said there had been no scientific study that linked pyriproxyfen to microcephaly, which has been confirmed in 462 babies, with 41 cases linked to the mosquito-borne Zika virus.
"Unlike the relationship between the Zika virus and microcephaly, which has had its confirmation shown in tests that indicated the presence of the virus in samples of blood, tissue and amniotic fluid, the association between the use of pyriproxyfen and microcephaly has no scientific basis," the statement said.
"It's important to state that some localities that do not use pyriproxyfen also had reported cases of microcephaly."
The government said it only used larvicides recommended by the World Health Organisation.
Hawaii declared a state of emergency over Zika yesterday, becoming the first US state to take such action.
David Ige, governor of the islands, said that the proclamation was "a preventative measure" as there have been no cases of the virus being transmitted in the state so far. Four people in Hawaii have caught the virus while abroad, the Centre for Disease Control said.
There have, however, been some cases of dengue fever on the island of Hawaii. The statement from the governor's office said such cases "continue to be fewer" and further between, but the battle to break the cycle of transmission continues.
"There have been no locally acquired Zika cases in the US or Hawaii, and we'd like to keep it that way," said Mr Ige. "This is about getting in front of the situation across the state."
Around 50 people in the US are known to have contracted the virus in 17 states.
All of them had travelled to Latin America.
Scientists around the world are currently racing to develop a vaccine for Zika virus, with clinical trials expected within a year to 18 months. (© Daily Telegraph, London)