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MedlinePlus is a service of the National Library of Medicine (NLM), the world's largest medical library, which is part of the National Institutes of Health (NIH). It was built as an online health information resource for patients and their families and friends.

MedlinePlus presents high-quality, easy to understand, relevant health and wellness information that is trusted.

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MedlinePlus at a Glance

  • Offers information on health topics, human genetics, medical tests, medications, dietary supplements, and healthy recipes.
  • Sourced from more than 1,600 selected organizations.
  • Provides 40,000 links to authoritative health information in English and 18,000 links to information in Spanish.
  • In 2018, 277 million users viewed MedlinePlus more than 700 million times.

Germs and Hygiene

What are germs?

Germs are microorganisms. This means that they can be seen only through a microscope. They can be found everywhere - in the air, soil, and water. There are also germs on your skin and in your body. Many germs live in and on our bodies without causing harm. Some even help us to stay healthy. But some germs can make you sick. Infectious diseases are diseases that are caused by germs.

The main types of germs are bacteria, viruses, fungi, and parasites.

How do germs spread?

There are different ways that germs can spread, including:

  • Through touching a person who has the germs or making other close contact with them, such as kissing, hugging, or sharing cups or eating utensils
  • Through breathing air after a person with the germs coughs or sneezes
  • Through touching the feces (poop) of someone who has the germs, such as changing diapers, then touching your eyes, nose, or mouth
  • Through touching objects and surfaces that have germs on them, then touching your eyes, nose, or mouth
  • From mother to baby during pregnancy and/or childbirth
  • From insect or animal bites
  • From contaminated food, water, soil, or plants
How can I protect myself and others from germs?

You can help protect yourself and others from germs:

  • When you have to cough or sneeze, cover your mouth and nose with a tissue or use the inside of your elbow
  • Wash your hands well and often. You should scrub them for at least 20 seconds. It is important to do this when you are most likely to get and spread germs:
    • Before, during, and after preparing food
    • Before eating food
    • Before and after caring for someone at home who is sick with vomiting or diarrhea
    • Before and after treating a cut or wound
    • After using the toilet
    • After changing diapers or cleaning up a child who has used the toilet
    • After blowing your nose, coughing, or sneezing
    • After touching an animal, animal feed, or animal waste
    • After handling pet food or pet treats
    • After touching garbage
  • If soap and water are not available, you can use an alcohol-based hand sanitizer that contains at least 60% alcohol
  • Stay home if you are sick
  • Avoid close contact with people who are sick
  • Practice food safety when handling, cooking, and storing food
  • Regularly clean and disinfect frequently touched surfaces and objects