The response to communicable diseases, outbreaks and emerging infectious diseases employs 2 different types of investigation: case investigation and outbreak investigation.

An outbreak investigation can be initiated by:

• The monitoring of trends of reported syndromes
• Alerts from health practitioners
• Media reports
• Notification from the Dept. of Public Health
• Rumours

There are 10 steps or guidelines that are performed in an outbreak investigation. They are not necessarily performed at the same time.

1. Confirm that an outbreak exists
   This may be done by comparing current data with earlier data on the disease in question. If no past data is available, observations of healthcare professionals may be used.
2. Verify the diagnosis
   This may be done by reviewing clinical findings and/or lab results.
3. Formulate a case definition
   Outline the criteria for inclusion as a suspect, probable or confirmed case.
4. Relate cases by person, gender, age, place and time
   Other information includes: Where did the exposure occur? Is there a common travel history among the cases? What is the time of onset of illness for the cases?
5. Formulate hypothesis
   This hypothesis should guide the investigation. It should incorporate all clinical, laboratory and epidemiologic facts, as well as what is already known about the disease process.
6. Plan and conduct detailed epidemiologic investigations
   Standardised investigation forms should be used for data collection. Controls (people who are not infected) should also be investigated and compared to cases. This will help identify what factors, cases were exposed to more frequently than controls and thus what was likely to have made the cases ill.
7. Analyse data
   This should be done as soon as possible after data is collected. Attack rates or rate for occurrence of illness among cases should be compared to that among controls.
8. Formulate conclusion
   Conclusions should be based on all relevant evidence.
9. Implement control measures immediately
   These measures should be practical and be initiated even before the outbreak is fully investigated. The effectiveness of control measures should also be assessed.
10. Reporting
    Reports should include both short and long term recommendations and should be disseminated to all appropriate stakeholders.

The purpose of these investigations is to prevent further spread of disease from the infected persons to others. This is accomplished by first discovering the source of the disease, whether it is food, environment or another person. If the source is identified as another person, then that person and all contacts would be screened and treated.

Outbreak Management

Management issues in the investigation of an outbreak include:

• Declaring to relevant people that an outbreak exists;
• Informing health providers that an outbreak is occurring and advise them how to proceed;
• At each stage of the investigation, consider who else needs to be informed and provide regular updates to necessary people;
• Inform the community;
• Inform the media;
• Consider the capability and capacity of the laboratories you will utilise during the investigation;
• Consider the availability of medical supplies that might be needed, for example, vaccines, antibiotics, oral re-hydration solutions;
• Seek assistance early; for example, obtain support from the Caribbean Epidemiology Centre (CAREC), if necessary;
• Declare the outbreak over; and
• Maintain surveillance activities to monitor the disease or syndrome that was investigated.

Communicable Disease Monitoring

Time trends are monitored to ascertain whether or not certain diseases are increasing or decreasing in incidence and/or changing in distribution. Such surveillance activities identify emerging threats, as well as assess the effectiveness of existing control measures.

Surveillance systems can be classified as being passive or active.

Passive Surveillance
System(s) in which, it is the responsibility of the data provider to forward surveillance information to a central control body. This requires less human and financial resources than active surveillance.

Active Surveillance
System(s) in which, information is requested or collected from the data provider.

In order to generate a complete and accurate picture of a given health situation the surveillance process requires data from several sources such as:

• Vital statistics
• Morbidity and mortality rates
• Case investigations
• Disease registries
• Outbreak reports
• Laboratory reports
• Sentinel reports
• Environmental reports
• Agricultural (animal and plant health) reports
• Surveys
• Censuses

Any member of the public, Bahamian or not, can make a report.

1. Contact the Epidemiology and Surveillance Unit by phone (see contact below) or
2. Report to your nearest Community Health Clinic.
3. Report detailed “concerns” about a potential disease outbreak.
4. Receive an interview appointment with a surveillance officer. (If you are unable to keep it, please call to reschedule before appointment time.)
5. Participate in interview process and outbreak investigation.

There is no application form for this service.

There are no supporting documents for this service.

There are no fees associated with this service.

Epidemiology and Surveillance Unit
Poncianna Hill Building
Meeting Street
P. O. Box N-3730
Nassau
New Providence
The Bahamas
Tel. (242) 502-4737
Fax.(242) 502-4874
Opening hours: 9:00 am to 5:00 pm, Monday to Friday, except public holidays