Swine Flu You remember the great swine flu epidemic of 2009, right? Really, you don't remember the school's being closed across the country after the first wave of fatalities? And how people stopped eating pork to such an extent that farmers simply slaughtered most of their pigs and then burned the meat? You don't remember that? Well, of course not. No-one does, because it didn't happen. It also true that no one knows why it didn't happen.

The interesting question at this point, as one looks back to the way in which decisions were made to stop an epidemic before it got started. In the aftermath of the flu season, when there had been no outbreak, many people criticized public health officials for having over-reacted. Those officials in turn argued two points. First, it was better to over-react than to under-react because the consequences of the former were far more dire than the consequences of the latter.

Furthermore, public health officials argued, there was no way to determine in the aftermath of the flu season to what extent the actions that had been taken had prevented an epidemic or pandemic of flu. Sometimes the fact that there is not a catastrophe that proves that the degree of response was exactly right. This paper examines the decision process that was followed in preparing for the 2009 flu season.

Rather than making any judgement about whether the right decision was made -- because it is of course impossible to determine afterward whether an epidemic was suppressed or simply never arose -- this paper walks through the decision-making process according to different models of choice that emphasize different underlying assumptions.

Bazerman and Moore's Decision-making Model

Bazerman & Moore (2008) and Bazerman (2008) have developed a six-stage decision-making model that can be applied to any field. This section of the paper uses this model to analyze the decisions made in preparing for the 2009 flu season. As will be discussed at greater length following the breakdown of the individual steps of this model and the ways in which they could have been used in setting public health policy, while this and similar models have many supporters, such models are often criticized for being overly mechanized and reductionistic.

The first step in Bazerman & Moore's (2008) model is to determine whether or not there is a problem. This sounds so elementary as to not needing to be said, but it is remarkable how often the "if it's not broke don't fix it" axiom gets ignored. Also included in this step are the following considerations: If there is a problem, does it have to be solved now? What happens if the decision if delayed? Who is responsible for making the decision? These steps are intuitive and indeed would be the first steps for most decision-making models that are being applied directly to problem solving.

The answer to whether the H1N1 flu virus had the potential to cause significant harm was certainly yes, something that was well-established in public health research. In the case of a potential flu pandemic, there is always the possibility that there may be truly catastrophic consequence. Indeed, thousands and usually tens of thousands of Americans die every year from the flu, and at least half a million people die from flu annually, many from secondary bacterial infections (Influenza, 2003).

In fact, the worldwide death rate of individuals from flu may be much higher than this because countries where there is likely to be a very high rate of infection are those same countries (primarily undeveloped nations in the tropics) that are both burdened with highly limited public health systems and limited means (and perhaps limited incentive) to report the actual rates of morbidity and mortality rates from flu. Even developing nations such as China have been slow to report the levels of infection.

The [government's] threats [to report the number of flu cases accurately] came after a prominent Chinese doctor, Zhong Nanshan, questioned why China's official H1N1 death toll remains in the double digits while other countries with much smaller populations post much higher numbers. He's convinced that [national] the government is covering up the spread of the virus.

That's a serious accusation in China, which suffered global embarrassment after attempting to conceal the deadly SARS [Severe Acute Respiratory Syndrome] virus in 2003. This time, China's sheer size may contribute to the problem of under-reporting. (Hatton, 2009)

The fact that initial reports of the seriousness of flu transmission rates...

The flu killed even healthy adults, who could feel "fine in the morning" and yet be dead by the time that the sun had fallen (Pandemic flu history, 2011).
Some of the statistics that help make the extent of the Spanish flu pandemic are the following: 1) Approximately 20% to 40% of the worldwide population became ill; 2) An estimated 50 million people died 3) Nearly 675,000 people died in the United States (Pandemic flu history, 2011). One of the reasons that this flu pandemic proved to be so lethal was that the virus responsible for it was new and so people did not have an immunity to it.

Flu viruses, like most viruses, can change quickly. It is for this reason that having the flu one year does not protect an individual the next year. Although the virus that comes around each year is similar enough to the previous version to be considered to be a form of the same disease, it can be significantly different. H1N1 was a virus that was significantly different from previous flu viruses, and so it had a greater potential than most versions of the flu to cause a high rate of infection and a high rate of death.

"It's a new virus whose biological properties we're still not sure of," said Andrew Pekosz. "And with influenza, it's been documented that different strains have a differential ability to cause disease in animals and in humans. And right now, we're getting mixed signals about this virus' ability to cause disease." (Researchers race to develop swine flu vaccine, 2009)

The 1918 flu pandemic also spread so quickly because it was carried home across the globe by soldiers returning home from war. H1N1 would not be transmitted in this way, but with international travel of hundreds of thousands of people during a single flu season, the spread of the disease could be incredibly rapid.

There had not been a flu pandemic as severe since that time, but the devastating consequences of a flu virus to which the human population had not been exposed, which had been demonstrated by the 1918-19 pandemic, that the emergence of a new strain of flu was enough to set off alarm bells throughout the public health community. Thus, step one of Baverman & Moore's model had been satisfied: There was a potentially serious problem, and it was one that had to be acted on with alacrity.

One of the key axioms of public health is that a vaccination program to be effective it must be started early on. Once a certain percentage of the population becomes infected (what the percentage is depends on a number of factors, including the type of pathogen) then a vaccination program will have very little effect. This precept is known as "herd immunity" or "community immunity" and is a well-established medical fact:

When a critical portion of a community is immunized against a contagious disease, most members of the community are protected against that disease because there is little opportunity for an outbreak. Even those who are not eligible for certain vaccines -- such as infants, pregnant women, or immunocompromised individuals -- get some protection because the spread of contagious disease is contained. This is known as "community immunity." (Community immunity, 2010)

This concept of "herd immunity" answers the question of why it would have been highly problematic to wait any significant length of time before making a decision to act.

Among the other key questions posed in step one of this model is, after determining that there is a problem is to determine who is responsible for offering a solution to the problem. The answer to this part of the model is that the most important actors in the solution are public health officials working on national and international levels. Viruses can fly across an international border instantaneously and so any intervention that has a chance of being effective must have international cooperation.

But other actors are also responsible as a necessary part of any intervention: Primary care physicians for diagnosing flu patients, individuals for being vaccinated and for acting in ways that limited the potential of infecting someone else, local officials for making decisions such as whether to close schools, virologists…