# 414
The goal, as stated in the CDC’s newly released document: Interim Pre-Pandemic Planning Guidance:Community Strategy for Pandemic Influenza Mitigation in the United States (available here), is to reduce the mortality and impact of any pandemic by slowing the rate of transmission of the virus in the community.
Ideally, we’d have a well-matched vaccine to distribute prior to any outbreak, but that is unlikely to happen. In fact, any significant quantities of vaccines would be unavailable during the first 6 months of a pandemic. Our second line of defense, antiviral medications, are also in short supply. All that are left are NPI’s: Non-Pharmaceutical Interventions.
Influenza is highly contagious, and left unchecked, would spread rapidly through any community. The greater the number of ill individuals at any given time, the greater the burden that will be placed on medical services, and the greater the strain that will be placed on society in general. Spreading out the infections over time, even if the total number of people infected isn’t appreciably lower, might prove advantageous.
Yes, it might prolong the pandemic period. Instead of a short, sharp pandemic, you might end up with a longer one. But you may also have time to develop and deliver a vaccine. You would place less of a burden on medical facilities. And you would have a better chance of keeping vital services going.
Is it risky? Yes. The longer a pandemic runs, the greater the risk to the economy. But the alternative is to do nothing, and accept tens of millions of people ill, or even dying, all pretty much simultaneously; and that could be disastrous.
The goal then is to try, as much as is possible, to keep the number of infections down so that the pandemic can be manageable, or at least more manageable than if nothing were done.
As stated in the CDC release:
The three major goals of mitigating a community-wide epidemic through NPIs are 1) delay the exponential increase in incident cases and shift the epidemic curve to the right in order to “buy time” for production and distribution of a well-matched pandemic strain vaccine, 2) decrease the epidemic peak, and 3) reduce the total number of incident cases and, thus, reduce morbidity and mortality in the community (Figure 1).
Reducing infections in a pandemic won’t be easy, particularly without a vaccine or antiviral medications. The CDC is working on ways to do this, and has come up with a variety of interim ideas. But they admit, it is a major challenge:
Factors responsible for these challenges include 1) a short incubation period (average of 2 days, range 1-4 days); 2) the onset of viral shedding (and presumably of infectiousness) prior to the onset of symptoms; and 3) the lack of specific clinical signs and symptoms that can reliably discriminate influenza infections from other causes of respiratory illness.
The CDC is therefore looking at a multilayered strategy to mitigate the infectiousness of a pandemic. Isolation of infected individuals is just part of their plan.
To summarize, isolation of ill individuals will reduce the onward transmission of disease after such individuals are identified. However, influenza is a disease in which infected persons may shed virus prior to onset of symptoms and thus are potentially infectious for approximately 1 day before becoming symptomatic. In addition, not all infected individuals will be identified because mild or asymptomatic cases may be relatively common. Isolation strategies are thus, at best, a partial solution.
The voluntary isolation of family members of those infected is also anticipated, but once again, is only a partial solution.
Similarly, voluntary quarantine of members of households with ill persons will facilitate the termination of transmission chains, but quarantine strategies are limited to the extent that they can be implemented only after cases are identified. Consequently, only a percentage of transmission chains will be interrupted in this fashion.
While controversial, the CDC is advocating the early closure of schools during a pandemic, and suggest schools could remain closed as long as 12 weeks.
Given that children and teens are together at school for a significant portion of the day, dismissal of students from school could effectively disrupt a significant portion of influenza transmission within these age groups. There is evidence to suggest that school closure can in fact interrupt influenza spread.
And finally social distancing in the work place, and in public will be promoted.
In addition, adults may further decrease their risk of infection by practicing social distancing and minimizing their non-essential social contacts and exposure to socially dense environments. Low-cost and sustainable social distancing strategies can be adopted by individuals within their community (e.g., going to the grocery store once a week rather than every other day, avoiding large public gatherings) and at their workplace (e.g., spacing people farther apart in the workplace, teleworking when feasible, substituting teleconferences for meetings) for the duration of a community outbreak
These are just some of the highlights. I invite my readers to download, and read the entire 108 page pdf document. Some of it is technical, but most of it is readily understandable. It is surprisingly blunt regarding our limited arsenal available in fighting a pandemic.
There have been outcries over the suggestion that schools be closed, and frankly that mystifies me. How many parents are really going to pack their kids off to school during a pandemic? Not many, I would think. Not if kids are contracting the illness, and dying. Not only does it put their kids lives at risk, they will be bring the virus home with them to infect the family. My guess is; the government won’t have to pull the plug on the school system. Parents will.
Will it be a problem? A burden to parents?
Absolutely.
But anyone who believes it would be business as usual during a pandemic is badly mistaken.
