While in Havana, I did not see a single mosquito. My aunt explained to me that it was because the state was fumigating homes (inside your home, not just spraying in the streets). On my last day we heard, then saw them coming down the street. Fascinating to me since here in the US most people would not take too kindly to military personnel coming into their homes to fumigate. Now, you could say no (like my aunt who asked them to come the next day because she hadn’t been prepared for them – you have to leave the house for 45 minutes when it’s done) but they make a note of it and you can’t say no too often. Also, I shudder to think what toxic chemicals they are using.
A final note – the newspaper has a column, much like a health inspection column, that reports businesses where any signs of mosquitoes have been found. They describe how many, what larval stage – and they are fined. Cuba takes the Zika virus, dengue and chikungunya very, very seriously.