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After a mild flu season last year, Influenza is here, and it has arrived early with a vengeance. Influenza is a group of closely related viruses which produce sudden and severe respiratory illness. We loosely divide flu into Type A, B and C with the A group being more troublesome. Viruses are very small particles of genetic material within protein coats that are microbiological dwarfs compared to monstrous bacteria. The influenza virus exists by attaching to and invading human cells. This is essential for reproduction and survival. The A group is more likely to spontaneously mutate and produce a new strain as a way to get around immune systems and survive. We refer to subtypes by using the geographical location of first isolation along with year of discovery, coupled with short-forms for two different proteins found on the coat. Hence names like A/Panama/2007/99 (H3N2), A/NewCaledonia/20/99(H1N1), or A/Fujian/411/2002. It is possible to be infected by several different strains through the course of a season.
Influenza symptoms appear suddenly and quickly: fevers, chills, muscle aches, stomach upset, cough, mild sore throat and fatigue, to name a few. It has been described like being beat up! I am a big believer in flu shots as anyone within arms reach has discovered. We are fortunate in having the distinction of being the only place in North America where a free mass vaccination program is in effect. It does have some problems. Public Health distributes the vaccine. It relies on waiting for phone calls and then finding someone to get to the drop area and retrieve the vaccine, a system of duplications and delays. It would make more sense to make large deliveries directly to concentrated medical centers, and thus get thousands of people immunized early. While one office is posting non-available signs, the next is immunizing people. It's confusing to patients and doctors alike. In the end, vaccine is available to all who are willing to step up and take the plunge. But stop to consider a few things. There are several different manufacturers and hence several vaccines on the market. Most of the vaccines in Ontario are of the split-virion type. There is no live virus in them. Vaccines are used to introduce the proteins found on the virus to our immune system. It is these proteins or antigens that our immune system uses to recognize foreign invaders. The idea is to get your immune system to respond, so that the feeling of a mild impending cold afterwards is normal. I think of it as teaching my immune system to respond at the first sign of smoke rather than waiting for flames. Some strains, like the Fujian, cannot easily be grown in egg culture medium and are not incorporated into vaccines. The good news being that the other major nasty strains are incorporated.
There are many fallacies in circulation regarding flu shots. Some adults who went through the "large painful needle in the butt stage" as kids are just plain scared of needles. For this group there is a nasal spray vaccine in trial stages. The flu shot also does not imply that you will get immunity from colds and diarrhea illnesses. Another common myth is the "I got the flu after the last shot excuse". I gained some insight into this myth while working my mandatory walk-in shift one Saturday. The clinic waiting room was jam packed with a line-up out the door. Patients with flu symptoms were mingling with patients wanting flu shots. Since immunity takes at least a week to kick in, it became apparent that they probably contracted influenza while attempting to get the shot. And hence a new generation of "I got the flu after the shot" emerged. Get your shot early. A flu shot is of no use if you got the flu. Infected people should not be attending flu-shot clinics. But if you do, ensure that you also have proper documentation of which vaccine you received, the lot number and expiry date. The only way this information gets into your medical record is if you put it there. Orwell's 1984 has come and gone, big brother might be watching, but he rarely talks to any of the little brothers. A computerized network to share medical information is still collecting dust on the 1985 Christmas wish list.
I admit that getting the flu shot is a bit of a gamble. We are never certain which strains are going to hit. It is an educated guess by using data compiled from around the world in the months before manufacturing begins. How long immunity lasts is also controversial. If you measure it in terms of circulating antibodies, it may be months. But immune memory mechanisms may extend it to years. Survivors of the devastating 1918-1919 Spanish Flu pandemic had evidence of immunity decades afterwards. This same Spanish Flu pandemic killed 19 million people, and I still worry about it. Symptoms struck young healthy people hard and fast. You got sick one day and died the next. It overwhelmed all available medical resources within hours of appearing in a community. If you discount the alien invasion theories, it seems that this particular strain was just a chance mutation and could appear again. Imagine surviving the trenches of WWI to come home to discover whole families have died. The projected death toll in Canada this year will be measured by the thousands. If immunity was truly short lived, then the virus would not need to mutate as often as it does. It is certainly not advantageous for a virus to wipe out its host, since it cannot reproduce on its own. Therefore it is my belief that repeated flu shots year after year may exert an accumulated benefit. Younger children require two flu shots if it is their first immunization year. There are no guarantees. In some people, the immunizing response just does not occur. One interesting observation from clinical practice is that people who have been vaccinated seem to do better when they do get the flu.
A friend in Los Angeles called me for a second opinion. Having just returned from her doctor, she informed me that she was diagnosed with influenza using a special swab test done right in the office, and then was given an expensive new medication to start immediately. I summarily informed her that this advanced yet simple technology is not available to the mere family doctor in the land of socialized medicine, to take her medicine and forget about getting a flu shot. I then began to drool. In an outpatient setting, when someone displays acute flu symptoms, having a confirmatory test at my side would be sheer heaven. Influenza is not always easily diagnosed. For this reason, thousands of "just in case" antibiotic scripts are written. No physician wants to miss a treatable illness, and most will proceed with caution. Influenza treatment is available, and most physicians prescribe it only when their certainty level is high. The community laboratory that I deal with had no viral kits available for testing when the first cases started walking in the door. They were on back order and the lab chief was uninterested in explaining why. It feels a little like landing on the beaches of Normandy and being told the generals are thinking about ordering bullets. I can also use blood samples to help diagnose the illness with a turn around time of weeks. But mostly, we check for strep throat, cross our fingers and hope our clinical instincts are right. Not exactly the preferred method if you are in a setting dealing with complete strangers. I did discover that one of our three community hospitals was equipped to do the bench top swab tests and the more definitive cultures. This makes it easier to track down strains in patients hospitalized with influenza, but the community situation is extremely difficult to track without technology.
In the end I did hedge my bet. I let my medical partner chase me down, corner me and stab me for the benefit of mankind. And so the timer begins to tick. Hundreds of ill patients are going to challenge my immune system with their airborne pathogens. It is the least I can do to try to protect my patients and be available to meet the challenge, should the projected pandemic get out of hand. I have little patience or sympathy for health care workers who use immunization programs as a rallying point for civil rights. It is neither the place nor the topic to take such a stand. The answer is yes!
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