Prepare for the investigation

Always be well prepared before leaving for the field. The preparations can be grouped into two broad categories: (a) scientific and investigative issues, and (b) management and operational issues. Good preparation in both categories is needed to facilitate a smooth field experience.

Scientific and investigative issues

As a health investigator, you must have the appropriate scientific knowledge, supplies, and equipment to carry out the investigation before leaving for the field. Discuss the situation with someone knowledgeable about the disease and investigations and review the applicable literature. Have a little bit of feedback about the investigation like previous similar outbreaks, what have been the sources, modes of transmission, and risk factors for the issue. Always be aware of what kind of health issue to investigate on. As a health investigator always carry along supplies or equipment to protect yourself. Before carrying out the investigation it’s important to carry out a plan action. What are the objectives of this investigation, what are the accomplishments? Having a plan of action upon which everyone agrees will allow you to hit the ground running and avoid delays resulting from misunderstandings.

Team work and communication

A communication plan must be established. The need for communicating with the public health and clinical community has long been acknowledged this allow the community members to be aware of what is being investigated. When caring out a health issue investigation always work in a team, this allow to gather information more faster and getting expose to different surrounding and people with different answers and experience.

Construct a working case definition

A case definition is a standard set of criteria for deciding whether an individual should be classified as having the health condition of interest. A case definition is a standard set of criteria for deciding whether an individual should be classified as having the health condition of interest. A case definition includes clinical criteria and particularly in the setting of an health investigation restrictions by time, place, and person. Whatever the criteria, they must be applied consistently to all persons under investigation.

The case definition must not include the exposure or risk factor you are interested in evaluating. Diagnoses may be uncertain particularly early in an investigation. As a result, investigators often create different categories of a case definition such as confirmed, probable and possible or suspect that allow for uncertainty.

Find cases systematically and record information

Usually the first effort to identify cases is directed at healthcare practitioners and facilities physicians’ clinics, hospitals, and laboratories where a diagnosis is likely to be made. Investigators may conduct what is sometimes called stimulated or enhanced passive surveillance by sending a letter describing the situation and asking for reports of similar cases. Alternatively, they may conduct active surveillance by telephoning or visiting the facilities to collect information on any additional cases. Finally, investigators should ask case-patients if they know anyone else with the same condition. Frequently, one person with an illness knows or hears of others with the same illness.

Develop hypotheses

Although the next conceptual step in an investigation is formulating hypotheses, in reality, investigators usually begin to generate hypotheses at the time of the initial telephone call. The hypotheses should be testable, since evaluating hypotheses is the next step in the investigation. In an outbreak context, hypotheses are generated in a variety of ways. First, consider the 5W's and H.  

Reconsider, refine, and re-evaluate hypotheses

Unfortunately, analytic studies sometimes are revealing. This is particularly true if the hypotheses were not well founded at the outset. When analytic epidemiology is revealing rethink your hypotheses. Sometimes a more specific control group is needed to test a more specific hypothesis. For example, in many hospital outbreaks investigators use an initial study to narrow their focus. They then conduct a second study with more closely matched controls, to identify a more specific exposure.

Recall that one reason to investigate outbreaks is research. An outbreak may provide an “experiment of nature” that would be unethical to set up deliberately but from which the scientific community can learn when it does happen to occur.

Confidentiality

Confidentiality is an important issue in implementing control measures. Investigators need to be aware of the confidentiality issues relevant to collection, management and sharing of data. If patient information is disclosed to unauthorized persons without the patient’s permission, the patient may be stigmatized or experience rejection from family and friends, lose a job, or be evicted from housing. Moreover, the investigators may lose the trust of the patient, Therefore, confidentiality the responsibility to protect a patient’s private information is critical.

Communicate findings

• An oral briefing for local authorities. This presentation is an opportunity for the investigators to describe what they did, what they found and what they think should be done about it. They should present their findings in a scientifically objective fashion, and they should be able to defend their conclusions and recommendations.
• A written report. Investigators should also prepare a written report that follows the usual scientific format of introduction, background, methods, results, discussion, and recommendations. By formally presenting recommendations the report provides a blueprint for action. It also serves as a record of performance and a document for potential legal issues. It serves as a reference if the health department encounters a similar situation in the future. Finally, a report that finds its way into the public health literature serves the broader purpose of contributing to the knowledge base of epidemiology and public health.

A health issue investigation series 

In recent years, the public has become more aware of and interested in public health. In response, health departments have made great strides in attempting to keep the public informed. Many health departments strive to communicate directly with the public, usually through the media, both during an investigation and when the investigation is concluded.