Controversial ideas considered in efforts to tackle the Zika virus.

FOX's Simon Owen reports from the European bureau:

Genetically-modified mosquitoes could be deployed, according to the World Health Organization, to wipe out the rival mosquitoes that are spreading Zika across the Americas.

It's a species described by health officials as an "opportunistic and tenacious menace." This concept has already been tested. Although, killing off an entire species raises environmental concerns.

Officials say other options include releasing sterilized mosquitoes, or bacteria which stop eggs from hatching.

Zika is suspected of being behind a spike in birth defects in Brazil.

In London, Simon Owen, FOX News.