We still have not had Chikungunya....live here 24/7....been to Kingston twice a month for the last few months where it is more common..live in the country where the eradication/fogging hasn't been as prevalent as the beach areas or major cities like Montego Bay, Ocho Rios or even Negril....I'm a mosquito magnet....
we spray once in the morning on a fairly regular basis and this obviously seems to be working for us...it appears you need to be diligent with the mosquito spray!