Once the proper authorities have decided that a public health response is needed, then usually an outbreak team will be in charge of the response.  The response is often focussed around the 10 steps of an outbreak investigation. For many of those steps, multidisciplinary expertise is required. For example steps 2 and 3 (confirm diagnosis and establish a case definition) often require close collaboration between field epidemiologist and public health microbiologist.

Steps 5 and 6 (determine population at risk and generate hypotheses) may need additional disciplines, depending on the context of the outbreak. For example with a vector borne disease, input from an entomologist may be required, in order to determine the spread of the vector and hence define the population at risk.

All of those different disciplines need to work in harmony, focussed on the same priorities to get through the 10 steps as quickly as possible. In large teams, coordinating the full outbreak response is the role of the outbreak manager. This person may have any of the disciplines as a professional background, with sufficient experience of having worked in many different outbreaks. Once you take the job of the outbreak coordinator, however, you need to be able to 'take some distance from your own discipline' and focus on the management tasks. So whether you are originally an epidemiologist, public health microbiologist, clinician, entomologist or public health decision taker, your job as coordinator is to focus on the process, and to align the work of all involved disciplines.

 

 

in smaller outbreaks and usually at the sub-national public health level it could happen that all of those responsibilities are carried by one person. In that case the challenge is to know when to 'switch your hat', for example in one moment you are designing questionnaires and data entry screens, and the other moment you are negotiating with the director of a nursing home to include the kitchen staff in the survey, and an hour later you may be at the ward, taking blood samples from cases, while at the end of the day you explain to the reporter of the local newspaper whether or not there are risks for the visitors of the nursing home.

It is just important to remember that in principle nothing changes in the steps that need to be taken in outbreak response. A main difference between small local outbreaks and large national ones, if the size of the outbreak team, and the need to coordinate and communicate at every level and during every step of the way.

Multiple disciplines, one team, one objective

Whether the manager of the outbreak team has a background in epidemiology, microbiology, health science or generic public health, he/she shares one single objective with the whole team:

  • To maximise the scientific quality of the investigation in a complex environment

The specific outbreak investigation objectives may vary according to the context of the outbreak and usually include "identify the source of the outbreak" or "identify the main risk factor for infection". The various disciplines contribute their expertise to achieve those objectives.

The field epidemiologist within the team is in charge of all epidemiological aspects of the investigation (study design, questionnaire, data handling, descriptive analysis, statistical inference) and brings this expertise in the team discussion.

The public health microbiologist is in charge of all microbiological and diagnostic aspects of the investigation (human, veterinarian, food, water, environmental, specimen processing, selection and interpretation of diagnostic tests, biosafety aspects).

In addition, the manager needs to know just enough of each of the disciplines within the team, to allow setting priorities and to decide in situations where specialists in the team cannot reach agreement.

Operational challenges in outbreak investigations

The aim of coordinating an outbreak investigation is to maximize the scientific quality of the investigation in a complex environment. What could be the operational challenges? Well, here are a few:

  • It is an unexpected event, so the public health system may not have been prepared to respond
  • Need to investigate quickly, especially if the source may still expose other people
  • Pressure for answers: family members, patients, journalists, politicians may want to have answers that you are yet unable to provide
  • Multiple agencies may have responsibilities: who will coordinate and which responsibility has priority?
  • Work will need to be carried out at many levels
  • You are in the media spotlight
  • Often, your investigation will have legal implications, as law enforcement agencies may want to use your evidence
  • You may arrive late; all kind of actions may have been started and you may need to cancel some decisions.
  • You may be working in a foreign country
    • You may be unaware of local sensitivities
  • You will need to feedback to various people
  • Stress, long working hours
    • finding time to rest and relax

You will need a structural approach to manage all challenges at one. Consider the following aspects:

Reasons for inviting you

  • You may have specific expertise
  • They may need more resources
  • Perhaps they want to share responsibility
  • There may be political or mass media pressure to invite you as an expert
  • It may be mandatory or in guidelines
  • They may need you to confirm local findings
  • They may expect you to perform specialised investigations
Each of these reasons may require you to perform differently. It will be helpful to agree on some written 'Terms of Reference ́ (ToR). Such a written agreement should clarify:
  • What are their expectations
    • expertise, tasks, time? 
    • what local resources are available?
  • What has already been done? 
  • What resources do you need to bring?
  • What is your role ?
  • Who is in charge?

Preparing to leave for the field

  • Consult colleagues (microbiologist, vet, entomologist....)
  • Review pertinent literature
  • Decide who will lead the team
  • Identify who provides support in head office
  • One page report before leaving
    • objectives
  • Arrange initial meeting for your arrival
  • Discuss with your colleagues at the Institute to organise follow up of your ongoing projects !!!!!
  • Organise your personal / family life
  • Bring your 'Epi-Pack':
    • Computer, calculator, mobile phone
    • Software 
    • USB, CDs 
    • Notebook
    • File templates
    • Standard questionnaires
    • Handbooks, relevant articles
    • Camera
    • (Laboratory equipment)
    • Telephone, address list: 
      • reference centers &persons
    • Maps, GPS
    • Others... (money, ”health kit”,)

When you arrive in the field

  • Provide help - don’t take charge
  • Meet with key people
  • Review and update status of problem
  • Assess sensitivities 
  • Identify local resources and skills
  • Discuss liaison
  • Set up communications with base

Outbreak Control Team

  • Membership
  • Leadership
  • Responsibilities
  • Lines of communication
  • Communication 
  • Decision making process

EPIET Lectures:

Logistical Aspects of Outbreak Investigations