In a paper just published on bmj.com, a US expert says that the public health measures taken in response to swine flu may be seen as alarmist, overly restrictive, or even unfounded.

Peter Doshi is a doctoral student at the Massachusetts Institute of Technology. He argues that plans for pandemics need to have further considerations than the worst case scenarios. He recommends a new outline in relation to epidemic disease.

Pandemic preparations during the last four years have focused on responding to worst case scenarios. For that reason, the response to the H1N1 outbreak was similar to a reaction to an unfolding disaster. Some countries erected port of entry quarantines. Others advised against non-essential travel to affected areas and some closed schools and businesses.

“Pandemic A/H1N1 is significantly different than the pandemic that was predicted”, says Doshi. He continues by mentioning that A/H1N1 virus is not a new subtype but the same subtype as seasonal H1N1 that has been circulating since 1977. In addition, a substantial portion of the population may have immunity.

“Actions in response to the early H1N1 outbreak were taken in an environment of high public attention and low scientific certainty”, he argues. In the first weeks of the outbreak, the sudden emphasis on laboratory testing for H1N1 contributed in magnifying the perceived risk.

Moreover, he comments that the World Health Organization has revised its definition of pandemic flu since the emergence of A/H1N1.

“The wisdom of many of these responses to pandemic A/H1N1 will undoubtedly be debated in the future”, he writes. The early response to the pandemic has revealed that the public health response is greatly influenced by longstanding planning assumptions about the nature of pandemics as disaster scenarios.

Doshi remarks that “If the 2009 influenza pandemic turns severe, early and enhanced surveillance may prove to have bought critical time to prepare a vaccine that could reduce morbidity and mortality.”However if this pandemic does not augment in severity, it may be a warning sign that there is a need to reassess both the risk evaluation and risk management strategies towards emerging infectious diseases.

He indicates that future responses to infectious diseases may profit from a risk assessment that largely conceives of four types of threat based on the disease’s distribution and clinical severity.

For example, a type 1 epidemic is severe disease affecting many people such as the 1918 pandemic. A type 2 epidemic infects few with mostly severe disease such as was SARS. A type 3 affects many with mostly mild disease such as the H1N1 pandemic may prove to be.

Public health responses not suitably tailored to the threat may be perceived as exaggerated. He warns that this deteriorates the public trust and as a result the general population ignores important warnings when serious epidemics do occur.

The achievement of public health strategies today depends as much on technical expertise as it does on media relations and communications. He says in closing that strategies that anticipate only type 1 epidemics bear the risk of doing more damage than they prevent when epidemiologically limited or clinically mild epidemic pandemics occur.

“Calibrated response to emerging infections”
Peter Doshi, doctoral student
BMJ 2009; 339:b3471
bmj.com

Written by Stephanie Brunner (B.A.)