Highlights:

A more common mosquito species ma be able to carry Zika 

Until now, the mosquito species Aedes aegypti has been identified as the main transmitter of Zika infections.

But Brazilian scientists have found they were able to infect another species, Culex quinquefasciatus, with the virus in a laboratory

In Brazil, Culex quinquefasciatus is 20 times more common than Aedes aegypti, the researchers said.

Culex quinquefasciatus also exists in more temperate climes, such as the southern United States, where it is known to carry the West Nile virus, and can survive winters.

Unlike Aedes aegypti, Culex quinquefasciatus could keep a virus in circulation during cold months.

Though the Culex mosquitoes prefer to feed on the blood of birds, they also commonly bite humans, especially in rural areas.

They also rest in trees and other high areas, while Aedes aegypti mosquitoes rests in low spots, often indoors.

This means efforts to kill each species, including pesticide use,  would need to be different.

Dr Grayson Brown, of the University of Kentucky, whose laboratory specialises in controlling mosquitoes, said if Culex mosquitoes were indeed proven to transmit Zika 'it would really complicate the public health issue.'

In an interview on Globo, Brazil's leading television network, lead scientist Dr Constancia Ayres, of the Oswaldo Cruz Foundation, said it was 'easy' to infect the Culex quinquefasciatus with the virus.

She said: 'We saw an ease of infection and an ease of dissemination of the virus to the salivary glands.'

While public health experts have cited Aedes aegypti as the mosquito overwhelming responsible for spreading Zika, with another species of the same genus, Aedes albopictus, also transmitting the virus in smaller numbers.

There has been evidence about other mosquitoes linked to Zika.

For example, researchers have found more than 20 mosquito species carrying the virus in Africa, although it was unclear whether they are all able to transmit the disease to humans.

Next, the Brazilian team will begin capturing Culex mosquitoes in areas near Recife, an area in the northeast of the country, where the virus is known to be circulating, in order to find out.

This research could take up to eight months, they said.

If a mosquito besides Aedes aegypti were found to transmit Zika infections in large numbers, it could make it more difficult to contain the current Zika outbreak.

Much remains unknown about Zika, including whether the virus actually causes microcephaly in babies, a condition defined by unusually small heads that can result in developmental problems.

Brazil said it has confirmed more than 640 cases of microcephaly, and considers most of them to be related to Zika infections in the mothers.

Authorities are also investigating another 4,200 suspected cases.

Traces of Zika virus have been found in the bodily fluids and tissue of mothers and babies affected by the condition.

Culex quinquefasciatus also exists in more temperate climes, such as the southern United States, where it is known to carry the West Nile virus, and can survive winters.