How many pathogenic bacteria are there

Your email address will not be published. Home » Research Talks » Microbiology. Audience: Student Researcher Educators of Adv. Audience: Researcher Educators of Adv. Speaker: Ralph Isberg. All Talks in Microbiology. Yersinia pestis bubonic plague. All Rights Reserved. Date last modified: May 4, Wayne W. Infectious Agents. Contents All Modules. Not quite so densely packed but impressive all the same, the bacteria present in the average human gut weigh about 1 kilogram, and a human adult will excrete their own weight in faecal bacteria each year.

Microbiological numbers can also span enormous scales in space and time. For instance, the largest known contiguous fungal mycelium covered an area of 2, acres 9.

At the other end of the scale, there are , atoms in a single Simian virus 40 SV40 virion. On the temporal scale, microorganisms can become dormant or form spores and survive for great lengths of time. For example, some viable bacteria extracted from amber were estimated to be 34,—, years old.

Perhaps the scariest numbers in microbiology relate to pathogenic microorganisms. Worldwide, 16 million people die from infectious disease every year, and many of these deaths are preventable. Approximately one in every 12 individuals, or million people worldwide, is living with chronic viral hepatitis, and the estimated number of new chlamydial infections per year is approximately 50 million, more than the population of South Korea.

The bacterium Clostridium botulinum produces a toxin so potent that 3 grams would be enough to kill the population of the United Kingdom and grams would kill everyone on the planet.

On this point, ignoring questions about what actually constitutes a species, estimates for the total number of microbial species vary wildly, from as low as , to tens of millions and higher. This means that the fraction of microbial diversity that we have sampled to date is effectively zero, a nice abstract entity to end on. These examples barely scratch the surface of the wondrous world of microbiology, and we encourage readers to continue to help us build a list of the numbers that inspire interest in the field.

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