Plant Viruses DO NOT Infect Mammals
This paper was brought to my attention by Prof. Gary Foster ( on Twitter. The research group behind it claimed Tobacco Mosaic Virus (TMV) can infect mice lungs. That's what they claimed but that's not what their study actually showed. There are plenty of reasons to not smoke, but being infected with a plant virus is certainly NOT one of them.

Firstly, I must point out that TMV is an extremely stable virus (see the links at the bottom of this post). It can persist in the environment for a very long time and stay infective (to mostly solanaceous plants). When placed in storage at 4°C/40°F, they can remain infectious (to mostly solanaceous plants) after 50 years. And that's how they spread - they are able to persist in the environment and contaminate anything which may come into contact with a host plant. To be able to do that, it must be very stable and not easily altered or destroyed by anything going on around it.

What this research group basically did can be summed up with this:
"Eh, so we got some TMV, stuck 'em in the lungs of some mice, and guess what? When we dissected the mice later, we found TMV in their lungs! Isn't that odd?"

No. As mentioned above, TMV is extremely stable and persistent in the environment. If you stick TMV in the lungs of mice, of course you are going to find TMV in there! Furthermore, the virus did not activate, nor did it infect the mice's cells. The mice with TMV in their lungs showed an immune reaction, but that would happen even if it was some non-biological particulate matter.

After they sacrificed the mice, they mashed up their lungs (which had TMV in them) and dabbed the resulting fluid on some tobacco plant and what do you know, the plants developed a viral infection! Which only goes to show how stable TMV actually is - NOT that the virus infected mice lungs.

Here's the take home message: Plant viruses are plant viruses and they CANNOT infect mammals, or even just animals in general - plants and animals are simply too biologically different for that to happen. 

Here are some reference on the stability (and other aspects) of TMV:
#biology   #virology   #botany    #scienceeveryday  
Shared publiclyView activity