Question: There are lots of diseases in the world but there isn't any vaccine of some. Why? Is it because you cannot do nothing about it or because they haven't been discovered?

Carmen Denman answered on 11 Mar 2015:

Hi 454sysb37,
Well – quite a question there. I’ll try to answer it but hope others can chime in too. Basically, you are correct, there are a lot of diseases out there caused by a variety of things. Firstly, to even make an effective vaccine that actually works and is safe, researchers need to understand what actually causes the disease and how the cause of the disease makes us sick. This takes years/decades of ‘basic research’ in the laboratory, exploring and experimenting. It may also take field work.

Some of the most famous application of proper field work was carried out by Jon Snow, the chap who first figured out that cholera was passed by water supply infected with Vibrio cholerae, rather than what people thought at the time which was by the air. He spent weeks wandering around Soho London asking people where their water came from and how many had fallen ill with cholera.

We now have a cholera vaccine, but it was only in the 90’s that is came about, far too late for many people who have suffered and died from cholera over history.

Discovering the bacteria that make sick is key- but then developing a vaccine also can take decades. Makes you very thankful for the vaccines we do have!

Cheers,
Carmen