RALEIGH, N.C. (WNCN) – A total of 19 people in North Carolina are known to have contracted Zika but the good news is that none have contracted the virus in the state.RELATED: woman found to spread Zika through sex for 1st time

The N.C. Department of Public Health told the State Emergency Response Commission Friday morning that all the cases were travel-related.

Zika spreads through mosquitoes and the state surveys the types of mosquitoes that exist in North Carolina, especially monitoring them in metropolitan areas, said Megan Davies, state epidemiologist, who gave the presentation.RELATED: Bat houses surge in popularity in hopes of preventing Zika

“To really sustain Zika virus, you need the right kind of mosquitoes breeding in backyards and gutters and containers, small containers,” she said. “And, you need a concentration of people. So if you’re out in the countryside and houses are a mile apart, you’re not going to get sustained transmission of Zika.”

Zika can also be transmitted through blood transfusions, so in North Carolina all blood donors are screened for risk factors of the virus, she said.

However, Davies said about 75 percent of people who contract Zika don’t have noticeable symptoms.

Those who do, most likely would have a fever, a rash or flu-like aches.