The Zika virus spreads through mosquito bites (like malaria). While less urgent now, it still poses a significant threat to everyone visiting destinations south of Miami, not just pregnant women.
As a result, the CDC recommends using “EPA-registered insect repellents with one of the following active ingredients: DEET, picaridin, IR3535, oil of lemon eucalyptus, para-menthane-diol, 2-undecanone. Always use as directed.”
Therefore, It’s a good idea to use insect repellent when leaving the ship in ports. I went on an excursion to the Mayan ruins in Mexico and was very glad I had on repellent–-mosquitoes were everywhere, even in October!
Fortunately, you won’t find mosquitoes on the open ocean. The sun decks on a cruise ship are too high for mosquitoes to fly, so you are safe on the ship.
In conclusions, the risk of Zika remains high, but the risk of negative effects from DEET is low when used properly.