Any virus that is excreted in feces in sufficiently large numbers and manages to survive outside the body of the host long enough to contaminate food has the potential to spread through this route.
Viruses differ from bacteria in that they are smaller, require a living animal or human host to grow and reproduce, do not multiply in foods and are nor complete cells.
Viruses involved in foodborne disease outbreaks include, but are not limited to norovirus, hepatitis A virus, human rotavirus, hepatitis virus, astrovirus, sapovirus, aichi virus and adenovirus, as well as human enteroviruses such as echoviruses, polioviruses, group A and B coxsachieviruses.
The great majority of these are RNA viruses, often small and containing single-stranded RNA. They infect via the intestinal lining, but some are transported to the over (and occasionally other organs) before causing disease.
Norwalk and Norwalk-like viruses are the leading reported cause of foodborne viral illness. A member of the Calicivirus family of viruses, Norwalk virus particles are 27 to 38 nm in diameter and consist of a single positive strain of RNA.
Norwalk virus was first discovered following an outbreak of epidemic gastroenteritis in a Norwalk, Ohio, elementary school in 1968.
Outbreaks of ‘food poisoning’ or foodborne gastroenteritis over the years have been assumed to be caused by bacteria, whether or not such organisms are identified.
Washing hands and cooking foods are probably the two measures that contribute the most to preventing foodborne viral disease.
Virus foodborne disease
