Being London based to I think we should make it clear that every winter in london id dreary!
You will not be disappointed with Belize - despite it being part of the Commonwealth we only discovered it 3 1/2 years ago and have not only been going back since but have now got a base there, which we hope will not blow away in te next hurricane!
Re your question, we took malaria tablets the first time we went but not since. I understand, however, that malaria is a greater risk in the jungle in the south of the country.
Nick