Concerns grow as research reveals another mosquito may carry virus

Research by scientists in Brazil have indicated that a mosquito more common than the one primarily known to transmit Zika infections may possibly be able to carry the virus.

According to the research, this is a development that can further complicate efforts to limit its spread. The scientists in Brazil had announced on Wednesday that they were able to infect another mosquito species, Culex quinquefasciatus, with the Zika virus in a laboratory.

The research was conducted by scientists at the government-funded Oswaldo Cruz Foundation in the northeastern city of Recife as part of an on-going trial. The trial involved researchers injecting 200 of the Culex quinquefasciatus mosquitoes with rabbit blood infected by Zika.

This result would raise concerns that Zika could be carried by a species more prevalent than the Aedes aegypti specie, the main transmitter of Zika infections. The Zika infections had been linked to thousands of birth defects as the virus spread rapidly in Brazil and other countries in Latin America and the Caribbean. However, the scientists said that much more research was needed to learn whether the Culex mosquitoes could actually transmit Zika infections.

"We saw an ease of infection and an ease of dissemination of the virus to the salivary glands,’’ Constancia Ayres, the lead scientist in the study was quoted as having told Globo, Brazil's leading television network.

The researchers said that the virus circulated through the mosquitoes' bodies and into their salivary glands, meaning they might be able to transmit a Zika infection by biting a person. Fabiola Tavares, Oswaldo Cruz Foundation spokeswoman, said that researchers who will begin capturing Culex mosquitoes in areas near Recife where the virus is known to be circulating.

According to her, this will enable them proceed to answer more questions on whether Culex mosquitoes in the wild are already carrying the virus as well as whether they can transmit Zika infections. She noted that the additional research could take up to eight months.

The World Health Organisation (WHO) had last month declared Zika outbreak as a global public health emergency.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.

In Brazil, Culex quinquefasciatus is 20 times more common than the Aedes aegypti mosquitoe species. Public health authorities had cited Aedes aegypti as the mosquito o responsible for spreading Zika, with another species of the same genus, Aedes albopictus, also transmitting the virus in smaller numbers.

There had also been evidence about other mosquitoes linked to Zika; for example, researchers found more than 20 mosquito species carrying the virus in Africa. However, it is unclear whether they all transmitted the disease effectively to humans.