Food Poisoning

Food poisoning is a term used to cover an unpleasant range of illnesses which can be caused by bacteria, viruses, chemicals, metals and poisonous plants.

Most of our work is concerned with investigating food poisoning, whether one off (sporadic) cases or outbreaks of illness. We also investigate outbreaks at institutions such as schools, nursing homes and nurseries.

It is commonly believed that food poisoning is associated with the consumption of food outside the home. It is our experience that this is rarely the case and the majority of incidents occur within the home environment. 

How do we investigate cases?

Environmental Health Officers have a duty to investigate confirmed cases of food poisoning and cases of infectious gastroenteritis. We are particularly interested in disease causing organisms commonly associated with and spread through food and water. Officers liaise closely with Public Health England. We normally investigate on average about 100 confirmed cases every year.

When patients present themselves to their doctor with a gastroenteric infection, faecal samples are usually requested and are submitted for analysis to the local hospital microbiology laboratories. These samples are screened for an extensive range of pathogenic organisms and if any of these are confirmed to be present, the matter is reported simultaneously to the patients doctor and also to the local environmental health department for further investigation.

Environmental health investigate the cases with a view to identifying:

• potential local sources of infection; and
• to offer advice as to prevent further spread of infection 

This is necessary to identify and take early action in the event of a food poisoning outbreak to minimise the risk and spread of further infection.

Following notification, the investigating officer will visit the address of the confirmed case as quickly as possible (normally within 24 hours). An interview is then carried out based on questions contained within an agreed standard proforma used throughout East Lancashire. Depending upon the organism, a range of questions will be asked about food consumed, contact with animals and places visited during the past few days (normally up to a weeks history may be required).

Certain types of 'high risk' people may be excluded from work and contact with other people.