Based on the available evidence right now, experts say that this is how the virus spreads: An infected person gets bitten by an Aedes mosquito, which then goes on to feed on another person, passing the virus to him or her in the process. In medical parlance, the mosquito is the most likely vector — a bug that spreads the disease.That said, Zika remains a rare virus, and since there aren’t a ton of cases to study, questions remain about how it spreads. For example, there is some research that suggests the Zika virus might be able to reside in a man’s semen — and if that’s the case, it might be possible to contract the infection through sex. Another long shot possibility: It might be able to spread via a blood transfusion . However, these things remain extremely unlikely at this point, especially considering that very few people in the U.S. have the virus. The bigger concern right now is the threat posed by Zika-carrying mosquitoes.Since the United States is home to two species of mosquitos that can spread the virus, Aedes aegypti and Aedes albopictus, experts expect that Zika will eventually migrate stateside. However, people from the U.S. have returned home with Zika viral souvenirs in the past — according to one press briefing , CDC officials said that 14 travelers tested positive for Zika between 2007-14.Plus, there have been outbreaks of dengue and chikungunya in the U.S. as well, and neither of these viruses have run rampant over the countryside. (Though perhaps it’s worth pointing out that the Zika virus is the fourth unexpected infection to reach the Western Hemisphere in the past 20 years, according to a 2016 article in The New England Journal of Medicine .) While experts seem to be cautiously optimistic, they’re also taking it seriously.Neither the CDC or the American College of Obstetricians and Gynecologists have suggested that women put off trying to conceive for any amount of time. However, if you’re pregnant or trying, avoid Zika-affected areas when possible.Since there’s no medication designed to target Zika specifically, the most doctors can do is manage symptoms. “The overwhelming majority of people get better on their own,” Dr. Lucey says. The CDC recommends rest and fluids, and treating any joint pain with medicines like acetaminophen No one has developed a vaccine yet. And since the symptoms seemed pretty mild (and the link to microcephaly wasn’t previously known), a Zika virus vaccine hasn’t been a top priority for experts and pharmaceutical companies. While recent events will probably change this, it takes years to develop a vaccine. If we were to see a Zika vaccine, it’s unlikely that it would be developed in under three years, Dr. Lucey says.