Editing Salmonella (section)

=== Non-invasive ===
Infection with nontyphoidal serotypes of ''Salmonella'' generally results in [[food poisoning]]. Infection usually occurs when a person ingests foods that contain a high concentration{{clarify|date=August 2020 |reason=how high? }} of the bacteria. Infants and young children are much more susceptible to infection, easily achieved by ingesting a small number{{clarify|date=August 2020 |reason=how small? }} of bacteria. In infants, infection through inhalation of bacteria-laden dust is possible.{{citation needed|date=July 2020}}

The organisms enter through the digestive tract and must be ingested in large numbers to cause disease in healthy adults. An infection can only begin after living salmonellae (not merely ''Salmonella''-produced toxins) reach the gastrointestinal tract. Some of the microorganisms are killed in the stomach, while the surviving ones enter the small intestine and multiply in tissues. Gastric acidity is responsible for the destruction of the majority of ingested bacteria, but ''Salmonella'' has evolved a degree of tolerance to acidic environments that allows a subset of ingested bacteria to survive.<ref>{{cite journal | vauthors = Garcia-del Portillo F, Foster JW, Finlay BB | title = Role of acid tolerance response genes in Salmonella typhimurium virulence | journal = Infection and Immunity | volume = 61 | issue = 10 | pages = 4489–4492 | date = October 1993 | pmid = 8406841 | pmc = 281185 | doi = 10.1128/IAI.61.10.4489-4492.1993 }}</ref> Bacterial colonies may also become trapped in mucus produced in the esophagus. By the end of the incubation period, the nearby host cells are poisoned by [[Lipopolysaccharide|endotoxins]] released from the dead salmonellae. The local response to the endotoxins is enteritis and gastrointestinal disorder.{{citation needed|date=May 2021}}

About 2,000 serotypes of nontyphoidal ''Salmonella'' are known, which may be responsible for as many as 1.4&nbsp;million illnesses in the United States each year. People who are at risk for severe illness include infants, elderly, organ-transplant recipients, and the immunocompromised.<ref name="Barbara2003" />