AH, LIFE IN THE TROPICSdo you mean your chick had Encephalitis? chance are that's what it had if it indeed had a mosquito borne disease and it also would have had bloody poop too.
good idea to put some stuff called Pre Strike in any standing water around your place.
HOPE if you have any dogs that you keep them on heartworm preventative too, not to mention
if you have any horses that they have their vaccinations against WEE, EEE, VEE current.