Disease outbreaks are public health emergencies that require urgent actions to investigate and respond to the situation.

Definition:

An outbreak is the occurrence of cases of an illness, specific health-related behaviour or other events, clearly in excess of normal expectancy in a community in a specific time period.

• An outbreak is limited or localized to a village, town or closed institution. However, the magnitude could involve wider geographic areas, even beyond one district, thus called an epidemic.
• If the cases occur in steadily increasing manner and are separated by an interval approximating the incubation period, the spread of the disease is probably due to person to person spread.
• On the other hand, if a large number of cases occur following a shared exposure e.g. an operation, it is termed a common source outbreak, implying a common source for the occurrence of the disease.
• A lower grade of the outbreak could be defined as one that can be dealt with within existing routine arrangements. A situation where a large number of patients are involved, wards closed to all admissions, and other hospitals are required to accept our patients would be considered a major outbreak.
• The severity of the outbreak is graded according to several factors.

1. The number of patients affected.
2. The type and virulence of organisms.
3. The endemic status of the organisms.
4. The resources available and necessary to control an outbreak

Purpose

The aim of this policy is to ensure a rapid, well-coordinated response to a major outbreak of infection, making efficient use of all health service resources in order to limit the spread of infection and minimize harm to patients, staff and visitors and to minimize the disruption of clinical services.

Policy Applies to all Hospital staff involved in clinical care delivery. Compliance by Credentialed Specialists, allied health personnel, contractors and other access holders who have patient contact will be facilitated by Hospital staff.

Rationale

The hospital must have the ability to implement an outbreak management plan when risk assessment identifies the presence of a serious disease that has the potential to spread within the hospital environment or community.

Definitions:

• Outbreak – Occurrence of cases of an illness, specific heath related behavior or other event, clearly in excess of normal expectancy in a community in a specific time period.
• Intervention – The point at which an intervention is required will vary according to the risk of infection to those exposed and the transmissibility of the pathogen.
• Management – The Infection Control Nurse & Infection Control Officer in conjunction with the Infection Control Committee will determine the nature and extent of response required in consultation with Credentialed Specialists and Senior Nursing Team.

Implementation

Identification of a Potential Outbreak

An outbreak may be identified by;

• Surveillance systems
• Laboratory microbiological data
• Alert by clinical personnel
• Regional Public Health, national or international alerts

Notification

The Infection Control Nurse and the Medical Superintendent / Manager Clinical Services must be notified and will initiate a risk assessment.

Risk Assessment

A risk assessment is required to establish the certainty of diagnosis of the infection in question. This will involve a Microbiologist or appropriate physician. The risks will be assessed using the following guidelines:

• Contagiousness of the disease
• The severity of the disease
• Number of people affected
• Legal requirements for notification to the Medical Health Officer

Key issues that are to be considered:

• Infected people are being appropriately cared for
• Staff providing care is protecting their own health
• Potentially exposed persons are correctly identified and informed
• Risk of infection to others is reduced by implementing control measures

Communication

Communicate and information Timely, up-to-date information must be communicated to the;

• Infection Control Committee

• Hospital Administration

• Medical Superintendent

• Manager of Clinical Services

• Credentialed Specialists

• Nursing Superintendent and Senior Nursing Team

• Public Health Authorities,

• Regional and National bodies,

• Medical Officer of Health as required

• Ministry of Health as required

Information may be provided to the public and media after consultation with the administration and local authorities. A final report that describes the outbreak, its probable causes, interventions and their effectiveness and summarizes the contribution of each team member should be prepared and presented.

Formation of an outbreak committee

The Outbreak Committee may include;

Microbiologist, Infection Prevention & Control Nurse, Medical Superintendent / Manager Clinical Services, members of the Infection Control Committee, representatives from affected clinical area, , external experts as appropriate.

The role of the Outbreak Committee is to:

• Gather information
• Plan strategy
• Implement control measures. The particular approach will depend on the nature and extent of the disease. (Appendix One)
• Communicate with patients, staff, credentialed specialists, other appropriate external agencies.
• Debrief
• Evaluation of the effectiveness of outbreak prevention and control measures will be completed by the ICO & ICN providing a written report to the Infection Control Committee.

Control Measures

A. Investigation

Epidemiological Methods- The investigation of an outbreak may require expert epidemiological advice on procedures. Formulation of a hypothesis regarding source and spread is made before undertaking microbiological investigations in order that the most appropriate specimens are collected.
Steps to be taken to investigate an outbreak –

STEP 1

• Recognition of the outbreak. Is there an increase in the number of cases of a particular infection or a rise in the prevalence of an organism? Such findings indicate a possible outbreak.
• The preliminary investigation must be begun by developing a case definition, identifying the site, pathogen and affected population.
• Determination of the magnitude of the problem and if immediate control measures are required. If so general control measures include
• Verification of the diagnosis. Each case should be reviewed to meet the definition
• Confirmation that an outbreak exists by comparing the present rate of occurrence with the endemic rate should be made.

STEP 2

• The appropriate departments and personnel and the hospital administration should be notified and involved.

STEP 3

• Additional cases must be searched for by examining the clinical and microbiological records.
• Line listings for every case, patient details, place and time of occurrence and infection details should be developed.

STEP 4

• Specific control measures should be implemented as soon as the cause of outbreak of identified.
• Monitoring for further cases and effectiveness of control measures should be done.
• A report should be prepared for presentation to the HICC, departments involved in the outbreak and administration.

B. Microbiological Study

• – The microbiological study is planned depending upon the known epidemiology of the infection problem.
• – The study is carried out to identify possible sources and routes of transmission.
• – The investigation may include cultures from other body sites of the patient, other patients, staff and environment.
• – Careful selection of specimens to be cultured is essential to obtain meaningful data.

C. Specific control measures:

Specific control measures are instituted on the basis of nature of agent and characteristics of the high-risk group and the possible sources. These measures may include:

• Identification and elimination of the contaminated product ;
• Modification of nursing procedures;
• Identification and treatment of carriers, and
• Rectification of lapse in technique or procedure

Specific Control Measures for Managing Infectious Outbreaks

• Agents responsible for Outbreak Control Precautions/Isolation Measures
• Cross-transmission (transmission between patient) Isolation and barrier precautions, as determined by an infectious agent(s)
• Transmission by hands Improvements in handwashing; cohorting
• Air-borne agent Patient Isolation with appropriate ventilation
• Agent present in water Checking of water supply and all liquid containers
• Food-borne agent Elimination of the food at risk; use of disposable cutlery
• Other measures – Identification and elimination of the contaminated products
• Modification of nursing procedures
• Identification and treatment of carriers
• Rectification of lapse in techniques or procedures
• Isolation/cohorting of infected patients
• Prevention of movement of staff and patients to other wards
• Non-admission of new patients and discharging patients, if possible
• Administration of immune serum to susceptible patients
• Treatment of close contacts (e.g., in diphtheria or meningococcal meningitis outbreaks)
• Introduction of new measures or improving existing procedures (e.g., alcohol disinfection of hands
• Closure of wards

Evaluation of efficacy of control measures

• The efficacy of control measures should be evaluated by a continued followed-up of cases after the outbreak clinically as well as microbiologically. Control measures are effective if cases cease to occur or return to the endemic level.
• The outbreak should be documented.

Major Outbreaks or Infections Problems Requiring Unusual Measures

These may include a large number of infections (e.g. due to salmonella species and Legionella species), requiring additional facilities, materials or major staff changes (e.g. closing of wards, opening a special isolation ward, more nursing, medical or domestic staff, more linen or CSSD materials, assistance from other hospitals or specialist laboratories). A single case of a particularly hazardous disease (e.g. Lassa fever or diphtheria) or an outbreak involving fatal cases or community involvement may all require special action.

Surveillance of Infection in Staff

This is a critical component of occupation heath safety and patient safety programmers. The surveillance for a specific infection may be done as part of routine prevalence surveys or during investigations of outbreaks. Treatment and management of these infections should be done after due consultations with infections disease specialists and medical officers. Surveillance in HCW is especially needed for blood-borne pathogens, enteric infections, MRSA and tuberculosis.

Environment and Equipment Surveillance

Unless there is an outbreak of infection, routine bacteriological sampling of floors, walls, surfaces and air is rarely indicated. For sampling, quantitative or semi-quantitative techniques should be used. The results should be reported as numbers of organisms per unit area or volume. The non-quantitative isolation of even known pathogens may also be misleading. Selective and/or indicator media should be used to count pathogens such as S. aureus or clostridium perfringens. Routine monitoring of sterilization and some disinfection processes is often necessary. Physical or chemical measurement of the efficiency of the process is generally preferable to bacteriological assessment. A sampling of treated equipment or fluids is of less value than process control. If sampling of the treated product is required, tests should be done by certain specialized equipment (e.g. respiratory ventilators), it may be advisable to confirm by bacteriological sampling that no pathogens are detected.

Surveillance of Antibiotic-resistant organisms

Hospitals and laboratories should support the surveillance and management of antibiotic-resistant organisms.
Hospitals and diagnostic pathology laboratories should support comprehensive programs for the surveillance and management of antibiotic-resistant organisms.

In establishing a national surveillance system, the objectives should be clearly defined. These may include:

• Reducing infection rates within health care establishments;
• Establishing endemic infection rates;
• Identifying outbreaks;
• Driving evidence-based changes in clinical practice;
• Improving clinical performance in health care establishments; and
• Evaluating control measures.

Outbreak control management procedures

1. Perform a preliminary evaluation of available information.

• Gather data – Notify key personnel

• Confirm diagnosis – Form an ‘Outbreak Management Group’

• Determine the magnitude & gravity of problem – Plan strategy

2. Seek additional cases.

• Develop working case definition – Plot data on epidemic curve

• Search for additional cases – Compare with previous experiences

• Check literature – Record information collected

• Surveillance of contacts

3. Formulate hypothesis

Test hypothesis: Case-controlled study, cohort, prospective intervention study, microbiological study

4. Control Measures

• Arrange for clinical care of patients – If necessary close services/wards:
• As necessary

1. Isolate patient(s);
2. Review practices;
3. Protect staff;
4. Educate – Factors influencing this include:-
5. Multi-resistant organisms
6. Number of patients involved
7. Additional host factors
8. Type of ward/department

5. Communication

• Document steps – Notify relevant personnel internal/external

• Designate a media person – Identify communication channels

6. Conclusion of investigation

• Data is collected until no new cases occur or rate returns to previously endemic rate

• Hold debriefing session

• Write a report

7. Evaluation

• Make recommendations where remedial action is required.

• Provide a written report to the Infection Control Committee