Going against the herd: The importance of mass immunity in society

Poster from before the 1979 eradication of sma...
Poster from before the 1979 eradication of smallpox, promoting vaccination. (Photo credit: Wikipedia)

Why is it that members of the public health community are worried about falling vaccination rates in the US when getting vaccinated is treated as a largely personal choice? Do our personal health decisions for ourselves and our children have an impact on the health of society as a whole?

The answer to this is that yes, our individual decisions do matter to society when it comes to combating the spread of contagious disease.

A large part of this is herd or community immunity; the way in which mass immunity in a population can control the spread of disease among individuals. Herd immunity is a major reason behind why so many deadly diseases have all but disappeared from American society; our vaccination rates protect many of those who are unvaccinated from contagious diseases. However, this is beginning to change in the US and we are beginning to see outbreaks of diseases that have not been of major clinical concern for decades.

Read on to find out more on how herd immunity and how it protects vulnerable members of society. Continue reading Going against the herd: The importance of mass immunity in society


Ask a Microbiologist #3: What’s in the almond milk?

Today’s installment of Ask a Microbiologist comes from a reader wondering what might be in that old almond milk in the fridge:

English: Raw Almond Milk
Raw Almond Milk (Photo credit: Wikipedia)

“I found an open container of almond milk in my fridge the other day and it was OLD – I’m talking it had been opened for at least a month at this point. I know that as soon as it’s opened, the pasteurized almond milk is immediately primed for bacterial breeding. I was just curious as to which pathogenic (entero) bacteria are most likely to colonize at this point; I’m curious because there were zero indications of growth (ie no swelling of the container and no abnormal smells, colors, or textures).”

-Wondering what’s in there

Well WWIT, I’m glad you asked this, as I was starting to wonder about my soy milk as well.

This is a very open ended question and three main ways to inoculate your drink that could potentially lead to different contaminating microbes, some of which could be pathogenic. Continue reading Ask a Microbiologist #3: What’s in the almond milk?

Beyond Fever: Fungal infections and the benefits of body heat

Histopathologic features of aspergillosis incl...
Histopathologic features of aspergillosis including the presence of conidial heads PHIL 4335 lores (Photo credit: Wikipedia)

So far on this site I’ve tried to address microbiology topics from all areas of the field; from the standards in bacteriology and virology to some more exotic parasites and fungal infections. When you look at the range of infections that people can acquire you see many bacteria, viruses, and parasites. However, invasive fungal infections, especially those that occur in healthy immune-competent hosts, are exceedingly rare when you compare mammals to insects, plans, and amphibians. I never gave this much thought until coming across a group of papers that together indicate that something as fundamental as a warm body temperature could protect us from a variety of pathogenic fungi.

Read on to see how endothermy may be a protective mechanism against fungal disease. Continue reading Beyond Fever: Fungal infections and the benefits of body heat