Infectious disease outbreaks: An innovative approach to evaluate and improve public health interventions

21 October 2005
Sydney South West Area Health Service

This project won the Baxter 2005 NSW Health Awards, Competence category.

Entries from the Baxter 2005 NSW Health Awards - full list

 Infectious_Disease_Outbreaks_Innovative_Approach_Evaluate_Improve_Public_Health_Interventions.pdf (1.2 MB)

Authors

Dr Bradley Forssman, SSWAHS Division of Population Health, Public Health Unit
Dr Leena Gupta, SSWAHS Division of Population Health, Public Health Unit
Mr Graham Burgess, SSWAHS Division of Population Health, Public Health Unit
Mr Patrick Maywood, SSWAHS Division of Population Health, Public Health Unit
Ms Deshanie Sathanandan, SSWAHS Division of Population Health, Public Health Unit
Ms Jenny Lane, SSWAHS Division of Population Health, Public Health Unit
Ms Linda Gardiner, SSWAHS Division of Population Health, Public Health Unit
Mr Geoff Tan, SSWAHS Division of Population Health, Public Health Unit
 

Abstract

Large public health interventions to control infectious disease outbreaks are common, but rigorous evaluation to improve the quality and effectiveness of these is rarely undertaken. Following a large community-based clinic to prevent a hepatitis A outbreak, a multifaceted and multidisciplinary evaluation was conducted involving consumers, health professionals and industry partners. The results of this evaluation were then used to produce practical operational guidelines for the planning and conduct of future interventions. These guidelines have been distributed to all public health units in NSW and may be included in the next edition of the “NSW Health Notifiable Diseases Manual”. The evaluation approach can be applied to all public health interventions across NSW and Australia to assist in the development of operational guidelines, in order to increase the quality of public health action in outbreak prevention.

Aim

To implement a multidisciplinary and multifaceted evaluation of an intervention to prevent a hepatitis A outbreak in order to develop operational guidelines to improve the quality and consistency of future public health interventions by May 2005.

Background

Prevention of infectious disease outbreaks may require large-scale public health interventions, including clinics to rapidly administer medications or vaccines to large numbers of people in at-risk communities. The implementation of such clinics is complex, however there are no guidelines to assist. In order to develop such guidelines, rigorous and multifaceted evaluation of interventions should be undertaken to understand where opportunities for improvement exist. Formal evaluations to assess infectious disease outbreak prevention have rarely been undertaken in the past.

In December 2003, in order to prevent a hepatitis A outbreak associated with an infected food handler in a club, the CSAHS Public Health Unit (PHU) conducted a mass vaccination clinic. This was the first of its kind reported in Australia. It was set up within 48 hours of the notification. We treated 768 of 1161 people attending with preventive immunoglobulin vaccine. In order to conduct and evaluate this clinic, a multidisciplinary team was formed, including medical, nursing, environmental health, and administrative staff from the PHU. We also sought input from NSW Health, consumers and industry partners.

Methodology

It was evident during the planning and conduct of the clinic that there was a lack of operational guidelines to guide decision-making related to the clinic and subsequent implementation. Further, there was no guidance on how to ensure the optimal engagement with the community, industry partners and other health professionals. Therefore, a multifaceted and multidisciplinary evaluation system was developed that involved:

• Detailed documentation of the process undertaken in this inaugural clinic;
• Focus group debriefing with PHU and NSW Health staff and with club staff and management;
• Development of a consumer feedback survey;
• Active surveillance for ongoing transmission of hepatitis A (ie case-finding within the community) to evaluate the effectiveness of the intervention; and
• Peer review of both the process and evaluation.

Planning and Implementation

Detailed documentation of the process was prepared through interviews with key staff members involved in setting up the clinic.

The focus group debriefings were held in February 2004, and attended by representatives from the community club, the local hospital, NSW Health and PHU. The focus groups identified what aspects of the clinic did and did not work, and made suggestions for improvement.

The consumer evaluation survey was developed through a brainstorming process by PHU staff and then refined further by pilot testing with a random sample of consumers. The survey covered consumer perceptions, satisfaction with the clinic, understanding of the information we provided and the consequences of our intervention. The survey was mailed to all adults who had attended the clinic, with follow-up of non-responders to maximise the response rate. Returned surveys were coded and analysed using SPSS 12.0 for Windows.

We contacted emergency departments, local doctors and laboratories to rapidly detect new cases of hepatitis A possibly linked to the club (active surveillance). We thoroughly investigated the reasons why these cases occurred despite the intervention.

Outcomes and Evaluation

This multifaceted evaluation was used to develop practical guidelines for planning and conducting clinics. These have been circulated to NSW public health units for local adaptation and implementation and may be incorporated into the next edition of the “NSW Health Notifiable Diseases Manual” (NSW Health, 2004).

Our documentation process formed the basis of the guideline that we have developed. Focus groups assisted in providing a number of practical suggestions for future action, such as increasing liaison between health agencies, the community and industry.

There were 624 consumer surveys returned (response rate 60.5%). Over 90% of respondents were satisfied with their experience of the clinic and found the information they received to be useful. Many (30%) sought advice from their GP, indicating the importance of GPs’ involvement in public health strategies. Additionally, there was a doubling of the proportion of people who perceived their risk of hepatitis A infection as unlikely (Figure 1), and there were changes in self-reported behaviours as a result of being involved in the clinic (66.8% stated they were more careful with their personal hygiene and 63.3% stated they were more careful where they dine out). This demonstrates that our consumer education process was effective. These findings were used to further refine the guidelines, with additional sections being included on communication with GPs and consumers.

Active surveillance revealed only 4 cases of hepatitis A linked to the initial case, which is far fewer than would be expected considering the initial risks of an outbreak prior to the intervention (CDC, 2003).

Two manuscripts, one about the clinic itself and another about the evaluation, have been submitted for external peer review. Presentations about the clinic, the evaluation and the outcomes have been given to local Councils and the NSW Public Health Network.

Future Scope

Multifaceted, multidisciplinary evaluations of this kind can used in future outbreak prevention throughout the NSW health system. Our guidelines can be used to guide service provision throughout the state, and further evaluation of their effectiveness will be encouraged. The guidelines are not only applicable to hepatitis A prevention, but may be used in prevention of influenza pandemics, meningococcal disease outbreaks and bioterrorism responses.

References

• CDC (2003) “Foodborne transmission of hepatitis A – Massachusetts, 2001”, MMWR, Vol 52, pp. 565-567
• NSW Health (2004) “Communicable disease report, NSW, for December 2003 and January 2004”, NSW Public Health Bull, Vol 15, pp. 44-53
• NSW Health (2004) “NSW Health Notifiable Diseases Manual”
• NSW Health (2002) “Easy guide to clinical practice improvement: A guide for healthcare professionals”