Infectious Disease

In this post I would like to take a closer look to the effects of the Global Environmental Change on infectious disease. Due to the rising temperatures (for further informations please read my post about Food Insecurity in Africa) it is likely that infectious diseases will spread into new areas and have a large impact on the human population.
During my research  for this topic I found a very interesting lecture held by Dr. Jonathan Patz. The lecture starts with a very basic introduction, but it focuses especially on how the health of humans and animals will be influenced by the Global Environmental Change and the change of ecosystems later on. Dr. Patz held this lecture at the UC Global Health Institute in 2011.

The whole video will be embedded at the end of this post, but as it is more than 30 minutes long I will try to sum up the most important points is a few key facts:

• The described trends do heavily apply to diseases that spread from humans to humans, because the influence of the environment does not have a great influence in that case. But for other transmission types like Animals -> Humans or Humans -> Animals -> Humans the changing environment is a very important factor. 

• The change is not only caused by the ecosystem change. A very important point is the strong correlation between the temperature and the parasite development time inside the mosquitos. A higher temperature will lead to a shorter extrinsic incubation period (EIP), so mosquitos will be infectious after a shorter time. This applies to diseases link for example Malaria or Dengue Fever.

• A very interested modeling for Zimbabwe and the spreading of Malaria due to only a predicted temperature rise is given in this lecture. It predicts a massive change especially in the highlands, where Malaria has not been a problem before. For further reading about this particular model I recommend this article: Click here.

• Historical examples are also given. For example the spreading of the Blue Tongue virus in Europe and the spreading of the West Nile Virus virus through the US.

Please keep in mind that in all the examples the Global Environmental Change is not necessarily the only cause for the spreading and changes. But it is very likely that it is at least one of the influential factors.

To take the most interesting facts and parts about the particular topic of this post I recommend to watch the video from 12:38 minutes.