Influenza Virus: How well do you know this enemy?
The flu is well known to all primary care providers - but contributor Terry Brenneman, MD, created 6 questions on topics you might not ordinarily discuss. Quiz time.
Influenza is not a new enemy to primary care but there could be a few things you don't know or haven't had a need to know. For example, how long after an infected epithelial cell is infected does it break apart? How many new viral particles are released when the cell does break?
You'll find the answers in the 6-question quiz that follows as well as 4 more interesting questions.
1. Which animal group is generally considered to be the primary host of the influenza A viruses?
Answer: B. Birds Aquatic birds host a wide variety of influenza A viruses in their GI tracts causing mostly asymptomatic infections.
2. Virologists classify influenza A based on variations of 2 glycoproteins located on the viral outer membrane, hemagglutinin and neuraminidase. What is the purpose of hemagglutinin?
Answer: D. Hemagglutinin attaches to sialic acid moieties found on the surface of some vertebrate cells that then enables the virus to enter the cell.
3. What is the purpose of the neuraminidase projection on the influenza virus?
Answer: B. The neuraminidase projection on the virus shears off the remaining sialic acid moieties on the cell surface so other flu viral particles don't get bound to an already infected or destroyed epithelial cell.
4. How long after a cell is infected does it break apart releasing the newly made viral particles?
Answer: C. ~10 hours
5. Approximately how many new viral particles escape when an infected respiratory epithelial cell breaks apart?
Answer: D. Between 100 000 and 1 000 000 new viral particles escape when an infected respiratory epithelial cell breaks apart.
6. What percentage of the viral particles released by a bursting cell are too defective to infect another cell?
Answer: D. 99% of the viral particles released by a bursting cell are too defective to infect another cell.
Terry Brenneman, MD, is a pediatrician and founder of Pediatric Partners, in Raleigh, NC. He is a long time contributor Patient Care© Online.
