What is yellow fever? Yellow fever is a disease that is spread through mosquito bites and is caused by a virus. In some people it can develop into serious illness and may even cause death. Yellow fever is found only in parts of Central and South America and Sub-Saharan Africa and parts of the Caribbean. Yellow fever vaccinations can only be given at designated centres and B.A Williams Chemist in Brentford is a designated yellow fever centre. Call the team today on 0208 560 3834 or visit t