Final answer:
A pathogen is a microorganism that causes disease and can contaminate food due to poor hygiene practices. Norovirus is a common example, and it can make people sick with a low infectious dose. The CDC reports millions of cases annually due to various pathogens like bacteria and viruses.
Step-by-step explanation:
A disease-causing microorganism that contaminates food usually through improper handling is called a pathogen. These microorganisms can include bacteria, viruses, parasites, and prions. One common example of such a virus is the norovirus, which is a leading cause of foodborne disease in the United States. Norovirus can contaminate food when infected individuals who have not washed their hands properly handle food, thus transferring the virus particles. These particles can make someone else sick in very small numbers, known as the infectious dose, which varies by the disease-causing agent and the susceptibility of the host, including age and overall health.
Most foodborne diseases are caused by poor hygiene practices during the handling or preparation of food. Consuming contaminated food can lead to various diseases, depending on the type and amount of the pathogen ingested. The CDC reports that millions of Americans get sick each year from foodborne illnesses. Common foodborne pathogens include the bacteria Salmonella, Clostridium perfringens, and Campylobacter jejuni, and viruses like norovirus. These pathogens colonize food and cause illness when ingested in significant amounts.