Florida likely has its first cases of “homegrown” Zika, transmitted by mosquitoes on the U.S. mainland, the state's governor said Friday.

What could this mean for Canadian snowbirds and others who like to travel to Florida? Here’s a refresher on the virus and the danger it can pose.

Are Florida mosquitos infected with Zika?

Officials are not yet completely sure. Florida has stepped up its screening of mosquitoes but so far, not one mosquito has tested positive for Zika .

And yet, Gov. Rick Scott confirmed Friday that Zika infections in one woman and three men in two counties were likely caused by bites of local mosquitoes.

If Zika has spread to Florida mosquitoes, it would not be surprising.The mosquito that carries Zika -- Aedes aegypti – is tropical but does circulate in the southern U.S., so “homegrown” Zika infections have been expected.

Still, U.S. officials expect only isolated clusters of infections, not outbreaks like those seen in countries such as Brazil, because of better mosquito control measures in the U.S.

Will I be in danger if I travel to Florida?

Remember, in most people, the Zika virus causes only mild illness – if it causes illness at all. It’s estimated that a full 80 per cent of those infected show no symptoms. The rest get a rash, and sometimes gastrointestinal discomfort.

Severe illness requiring hospitalization is uncommon; deaths linked to Zika are even less common.

But as we’ve been hearing for months, a Zika infection during pregnancy – especially early in pregnancy – can lead to birth defects, including microcephaly, the condition of an undersized head.

Are there other ways to contract Zika besides mosquitoes?

Zika can also spread through sexual contact. In fact, there have been several cases of infection in people who did not travel to Zika-affected countries but became infected after sex with infected partners.

The virus can be spread from men to women, men to men, and women to men. It can also be passed before the infected person develops symptoms and even after their symptoms end.

Should I avoid Florida if I am pregnant or planning to become pregnant?

U.S. health officials have not recommended that pregnant women avoid travel to South Florida. But they did say Friday they will be looking at several factors, including how many mosquito-caused cases are found, before deciding whether to issue further recommendations.

The Public Health Agency of Canada recommends that pregnant women and those planning a pregnancy avoid travel to Zika-affected countries. If travel cannot be avoided or postponed, strict mosquito bite prevention measures should be followed.

It is strongly recommended that women planning a pregnancy wait at least two months after return from Zika-affected area before trying to conceive to ensure any possible Zika virus infection has cleared the body.

How can I avoid infection?

The best way to prevent infection is to prevent mosquito bites. That means:

  • wearing long-sleeved shirts and long pants, even during the day
  • using insect repellent
  • ensuring there are screens on the windows
  • sleeping under a mosquito net if there are no screens on the windows
  • removing standing water around the home, where mosquitoes breed.

Because the Zika virus can persist in semen for an extended period, men who have been to Zika-affected countries and whose partners are pregnant are advised to use condoms or avoid sex for the duration of the pregnancy. They should also wait to conceive for six months after their return.