# 1723
The prevailing theory, based on our experiences in the Spanish Flu of 1918-1919, is that a pandemic will come in several waves lasting 6 to 12 weeks, occurring over a year or two.
Whether that holds true for the next pandemic is unknown. The world is a far different place than it was 90 years ago, and our more mobile society may change the equation.
We are told it will be at least 6 months after a pandemic begins before we will see a vaccine, and then, only in limited quantities. Anti-viral drugs such as Oseltamivir (Tamiflu) are hoped to reduce the severity of the illness, but again, world stockpiles are limited, and there are concerns that it may lose its effectiveness over time.
We are left, then, with only one practical defense during a pandemic. The use of NPI's, or Non-Pharmaceutical Interventions. These may include:
- Social Distancing
- Frequent Hand Washing or Sanitizing
- Covering your coughs and sneezes
- School and day care closures
- Masks, gloves, and other barriers
- Isolation of those infected
- Voluntary quarantine of those exposed
The idea behind NPI's is to slow down the transmission of the virus. Prevention is the keyword, and the best thing about NPI's is that most don't require special equipment or supplies.
Individually, none of these items is likely to make much of a difference, but when `layered' on top of one another, they can reduce the number of people infected at the same time.
Social distancing is the avoidance of crowds, and trying to keep some separation between you and others. While the debate over exactly how influenza can be transmitted isn't resolved, most scientists believe that the majority of infections occur at close range via large droplets or from fomites (contaminated inanimate objects).
This `danger zone' is somewhat nebulous, but 6 feet of separation is generally recommended. Airborne transmission over longer distances is considered by some to be possible, but has never been conclusively demonstrated.
While some people have interpreted social distancing as social isolation, and plan to sequester themselves in their homes for weeks or months at a time, that isn't the intent of this NPI.
For social distancing to work, some public events may need to be canceled, employers may need to stagger workshifts, and the use of some forms of public transportation may be curtailed.
Frequent Hand Washing is often cited as a prime preventative measure, and as an old medic who was used to putting his hands in some pretty awful places, I can attest to the wisdom of doing so. Old habits die hard, and I still wash my hands 10 times a day.
Influenza viruses can live for hours on inanimate surfaces, depending on the ambient conditions (sunlight, humidity, temperature). We can pick them up by touching doorknobs, grocery cart handles, telephones, etc.
Deadly though they may be, influenza viruses are relatively easy to kill. Ordinary soap, hot water, and vigorous handwashing can do a pretty good job on the virus. But to be effective, it must be done properly and often.
Alcohol gel sanitizers are also good, particularly when a sink and soap aren't available. I carry a small bottle of gel in my pocket, and keep one in my car, for just that purpose. To be effective, they need to be at least 62% alcohol. Check the label.
Covering coughs and sneezes can reduce the transmission of influenza viruses. In the UK recently they introduced the Catch It, Bin It, Kill It campaign.
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CATCH IT - Germs spread easily. Always carry tissues and use them to catch your cough or sneeze.
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BIN IT - Germs can live for several hours on tissues. Dispose of your tissue as soon as possible.
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KILL IT - Hands can transfer germs to every surface you touch. Clean your hands as soon as you can.
Coughing or sneezing into your sleeve is preferable to using your hands. The CDC recommends:
- Cover your mouth and nose with a tissue when you cough or sneeze.
- If you don't have a tissue, cough or sneeze into your upper sleeve, not your hands.
- Put your used tissue in the waste basket.
- Wash with soap and water.
or - Clean with alcohol-based hand cleaner.
School Closings are going to be controversial, but in the minds of many people, they will be integral in the slowing down of a pandemic. As any parent can attest, once a flu bug hits a school or day care center, it doesn't take long for nearly everyone to catch it, and bring it home to their families.
It simply isn't possible to maintain safe social distance in a school environment. Classroom may have 30 or more people in them, desks are lined up next to one another, and hallways are often a seething throng of students making their way to their next class.
It is hard to envision a better place for a virus to thrive than in a school.
There are plans to close schools for as long as 3 months at a time, once a pandemic virus begins to spread in this country. Not everyone is onboard with this policy, and it will certainly cause hardships. Working parents often depend on schools to watch their kids while they work, and many kids depend on the school lunch program.
The alternative, however, is far worse. Pandemic influenza viruses often have shown a proclivity for the young, and the H5N1 virus is no exception. So far, half of all deaths recorded from the bird flu virus have been in people under the age of 20.
The use of masks and gloves by the general public is controversial because they will be in short supply, must be donned and removed properly, and may inspire unwarranted confidence in the level of protection they will provide.
Since most flu victims will be cared for in their homes (govt. estimates of 95%) by their families, it makes sense to have these forms of barrier protection on hand. A person's highest risk of contracting the virus is while taking care of someone known to be infected.
The general wearing of masks in public, however, hasn't been recommended. At least not yet. Simple surgical masks aren't likely to provide much protection, and the more expensive N95 masks are not only going to be in very short supply, they are only good for a few hours of wear.
Isolation and Quarantine sound draconian, and could be I suppose, but as currently described by the CDC they are simply reasonable precautions.
Isolation of the infected will simply mean, if you are sick . . . stay home! Don't go to work, or to the mall. Don't spread the virus.
Households should be prepared to isolate anyone sickened, as much as possible, from those not yet afflicted.
Voluntary quarantine of those exposed is a little more controversial. It is believed possible to shed the influenza virus for a day or two before showing symptoms. In other words, you can look perfectly healthy and yet be infectious to others.
A voluntary quarantine asks that members of a household who have been exposed to an infected family member stay home until the incubation period has passed.
This is the reason the government is promoting the idea that every household have sufficient food, water, and medicines for at least 2-weeks. Many agencies are suggesting up to 3 months worth of food and supplies would be prudent.
Note: The implementation of mandatory, or large scale quarantines during a pandemic is viewed by most public health officials as both futile and counter-productive.
For more information on how to prepare, go to GET PANDEMIC READY.
Through the use of these NPI's it is hoped that the rate of transmission, and the number of people simultaneously sickened, can be dramatically cut during a pandemic.
The chart above, taken from the PNAS journal article entitled Public Health Interventions and Pandemic Intensity During the 1918 Influenza Pandemic , shows the excess mortality in two American cities. The tall spike represents Philadelphia, while the lower curve represents St. Louis.
Scientists believe the startling difference in attack rates, and mortality, in these two cities can be explained by the way each city dealt with the outbreak.
In St. Louis, the Health Department closed public venues such as schools, theatres and churches very early in the outbreak, while Philadelphia did not.
As a result, Philadelphia experience a sharper, albeit shorter pandemic wave. St. Louis saw fewer deaths on a weekly basis, but the outbreak lasted longer. Roughly twice as long, in fact.
The uptick in cases in St. Louis, late in the outbreak, indicates that some people stopped their social distancing too soon, and the pandemic wave re-ignited.
It is hoped that by reducing the number of people simultaneously infected, the impact on society will be lessened. Hospitals would be better able to cope, and essential services would be less strained by absenteeism and demands on their departments.
The choice, it seems, is between a short pandemic wave, where we see a lot of infections (and deaths) over a relatively short time span, or a longer wave, with fewer weekly infections.
The total number of infections, and deaths, may not differ much in the end. But the impact on society, and the demands on services would be lower with a longer, less steep infection curve.
Obviously, a longer wave entails some difficulties that a shorter wave does not. Schools would remained closed for up to 3 months, many businesses would take a prolonged economic hit, and people would need to be prepared for longer periods of disruption.
Still, when you consider the alternatives, the St. Louis model is far preferable.
