A notifiable disease is one of about 30 infectious diseases and causative agents which must be reported by health professionals to the HPA to assist the agency with the detection of possible outbreaks and management of single cases.
During the Games the HPA monitored reports of disease with particular scrutiny for any association with the Olympic venues.
When a case of any notifiable disease was reported to the HPA’s local Health Protection Units (HPUs), staff would provide public health advice to the reporting doctor. This included advice on the length of time to isolate the ill person, whether people in close contact with the ill person required vaccination, or whether people in the same household needed antibiotics to prevent further spread of the infection. HPU staff would also advise on which samples should be taken and ensure that they were delivered to the correct HPA laboratory for testing. Databases would be searched to check whether the case could be linked to others which may have indicated a potential outbreak.
An outbreak of an infectious disease is defined as:
Outbreaks are detected by the HPA, Local Authorities or microbiologists at a local or national level. Each organisation has its own procedures for surveillance, detection and control and, as soon as it becomes apparent that an outbreak may exist, immediate contact between these organisations is established. They consider the facts available and will determine whether or not an outbreak does exist.
Often it is necessary to collect further evidence before outbreak decisions can be made. Key objectives in this initial stage are to determine:
An Outbreak Control Team (OCT) is established if an outbreak has one or more of the following:
The OCT brings together key clinical staff, microbiologists, epidemiological expertise, environmental health and other Local Authority staff, and any other relevant agencies (for example the Food Standards Agency and Defra), to find out the nature and extent of the outbreak and put in place effective measures to control it. This includes ensuring that ill people receive appropriate treatment, samples are tested in the laboratory, possible sources such as foods are removed from sale and restaurants or other food outlets thought to be the source are closed until safe practice can be re-established.
Incidents may be defined as the exposure of one or more people to a substance (chemical/radiological/biological) which may damage health. They are handled in a similar way to outbreaks by convening a team which, in addition to public health expertise, has scientific expertise in the particular hazard. The team would provide incident specific advice on how to decontaminate people, whether specific treatment is required and the measures needed to prevent other people suffering the same exposure. The team would also contribute advice on how to clean up any substance in the environment safely.