Final answer:
The statement is false; the infectious dose refers to the amount of a pathogen needed to cause disease, not the amount of bacterial toxin ingested. Various factors impact the infectious dose, and it is distinct from the lethal dose, which is related to the amount of pathogen or toxin needed to kill a host.
Step-by-step explanation:
The statement is False. The infectious dose is the amount of a pathogen that must infect a person to cause disease, not the amount of bacterial toxin. The number of pathogens required to cause infection can vary widely among different organisms and can be influenced by various factors including the virulence of the pathogen, the immune status of the host, and the environment.
For instance, a single cell of Salmonella enterica serotype Typhimurium can result in an active infection, while S. enterica serotype Typhi often requires as many as 1,000 cells to cause infection. However, the severity of the disease doesn't necessarily correlate with the infective dose.
It's important to differentiate between infectious dose and lethal dose (LD50). The lethal dose is the amount of pathogen or toxin required to kill 50% of a test population and is not the same as the infective dose that causes illness.
In the context of foodborne illnesses, both infection and intoxication can occur, with toxins being the main agent causing symptoms. Infection results from ingesting pathogens that then produce toxins in the body, whereas intoxication occurs when toxins produced in food are ingested.