A virologist at the Bernhard-Nocht Institute for Tropical Medicine in Hamburg, Germany, has suggested that Zika virus infection is the only vector-borne disease that may be transmitted by sexual intercourse.
The first suggestion that you could get Zika virus infection from both a mosquito as well as a sexual partner came in 2008, when an American scientist contracted Zika in Senegal and fell ill a few days after returning home to northern Colorado. His wife got Zika soon after, even though she had not travelled anywhere far for several months. More weight was placed on this suspicion by research published in 2015 that found the presence of the Zika virus in semen.
Researchers have commented, however, that this does not mean sexual transmission will take over from mosquitoes as the main means of the spread of the Zika virus, but it certainly would make prevention more difficult than simply wearing mosquito repellant.
Whilst this additional route of transmission could contribute to the spread of the virus in the case of an epidemic, its effect is likely to be very small since, when a person is sick with Zika, having sexual intercourse is less likely to occur.
Source: Jamaican Observer