I Don't Like Bats But...

Bats and I are not friends. It is not that vampire thing it is just that they tend to leave their droppings everywhere, and carried rabies. But New Scientist has an interesting piece that has some import. They note:

Bats provide a refuge for some of the most lethal viruses known, including Ebola, Marburg, Nipah and SARS. Now we may know why the animals tolerate these lethal viruses – and it’s because flying is such hard work. Peng Zhou of the Wuhan Institution of Virology in China and his colleagues studied the immune systems of bats and flightless mammals. They focused on free-floating DNA within cells. This can happen as the result of a viral infection, as the viruses hijack the cells’ DNA replication apparatus to copy their own genetic material. But it can also happen during strenuous exercise, which creates chemicals called free radicals that build up in cells and damage the DNA, releasing fragments of it. Most mammals don’t have to perform hugely strenuous exercise, so their own DNA rarely leaks out into their cells. As a result, if their immune system detects any free DNA, it interprets it as an emerging viral threat and begins fighting back. The trigger for action is a sensor molecule called STING, which swamps the viral infection with antiviral substances called interferons. However, bats fly and this is extremely strenuous, so their DNA often does leak out. This could lead the bat’s immune system to mistakenly attack the animal’s own tissues. To avoid this, bats appear to have evolved milder reactions to viral infections, allowing the bats and the viruses to tolerate each other.

This is an interesting phenomenon and worth the study. It is even more of a reason to beware of bats. If they can do rabies then they can do all of the above. I understand the benefits of bats but the downside should be considered also. Just a thought!