Microbiology Fun

Some of you may be interested in Pritish's new line of microbiology-related T-shirts. They're hilarious!

http://www.pritishirts.com

He's open to suggestions for more T-shirt designs.

Case of the Week 26

Here is a tricky case for you to ponder. I was doing some research a few years back, using beef as a control for immunohistochemical staining. My fellow researchers and I were very surprised to see the above cysts in our beef samples. These were run-of-the-mill sirloin cuts bought at the local supermarket.

Identification?
What are these parasites, and could they potentially infect humans?

Answer to Case 26

This is a classic example of the muscle cyst form of Sarcocystis. This apicomplexan parasite has a lifecycle similar to Toxoplasma gondii. Depending on the species, humans can be the definitive host (and contract a GI infection) or the intermediate host (and form muscle cysts). This particular species is S. cruzi, which is not a human pathogen. However, S. hominis is also found in beef and can be transmitted to humans. Interestingly, S. hominis has been not been reported in the U.S., but may be found in beef from many other regions, including Europe.

Congratulations to Dr. R - the only one to get this correct (I told you it was tricky!)

Case of the Week 24

Here's another video from the wonderful world of entomology.
These tiny little things regularly crawl on us. Yes, even if we shower regularly.
Identity?
What disease is associated with them?

Answer to Case 24

Identity?
Ian got this one - these are Dermatophagoides mites (House Dust Mites)
These microscopic mites are in our soft furnishings (especially our beds), feeding on our shed skin flakes, and depositing feces. It is the feces that can trigger an allergic reaction in susceptible individuals.

What disease is associated with them? The allergens in house dust mite feces can trigger asthma, eczema, perennial rhinitis.