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Toxicology + Industrial Hygiene Consulting

Do you know a YOPI?

Karen Michael, MPH, PhD

March 2, 2018

YOPI’s are people who fall into the category of the very Young, very Old, Pregnant or Immune-compromised. This is a handy acronym for referring to a group of people that are generally at a higher risk of acquiring infectious diseases and developing complications from them.

Immune status plays a primary role in designating this population as a higher risk or "sensitive" group. The immune system is an important line of defense against all the microbes, such as bacteria, viruses and fungi, in our environment. The very Young do not have fully developed immune systems. They also interact with their environment differently than adults do (for example, more hand-to-mouth behavior, closer to the ground, etc.). The very Old can have compromised immune systems and they are also more likely to have additional risk factors such as diabetes and heart disease than non-YOPI's. The inclusion of Pregnant women in this category can be attributed to the sensitive, developing fetuses they are carrying, and also to the substantial metabolic changes associated with pregnancy . And finally, Immune-compromised people such as cancer or transplant patients and people with HIV-AIDS are at higher risk of infection and other diseases due to a lower level of immune function. YOPIs also tend to have more frequent interactions with healthcare settings, which can be a hotbed for infectious disease transmission.

Using this designation can help public health practitioners and researchers quickly distinguish between lower and higher-risk groups of people. Most healthy adults, or non-YOPI's, are at a relatively low risk for developing life-threatening complications due to common infectious diseases. This does not mean they will avoid the cold or flu bug that circulates around their office or school building, but they typically require fewer precautions to avoid complications and are more likely to bounce back quickly.

YOPIs and non-YOPIs alike can lower their risk of "catching" the latest "bug" by practicing good hygiene measures, such as frequent and adequate handwashing, covering  coughs and sneezes with tissues, and routine disinfection of high touch surfaces.

Links used:

  1. Handwashing:
  2. Coughs and sneezes:
  3. Disinfection:

About the Author

Karen Michael, MPH, PhD

Industrial Hygienist and Bacteriologist

Karen Michael, MPH, PhD, is an industrial hygienist who specializes in microbial hygiene in clinical, residential, and commercial settings. Her practice at Veritox® focuses on environmental contamination with microbiological pathogens, infection prevention and biosafety. Specifically, her expertise deals with collecting and analyzing microbiological data that have no regulatory exposure limits.

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