Flu shots and other adult immunizations
“Tis the season” to get flu shots and while you are at it, consider other immunizations you and your family may also need.
First, a brief reminder about flu shots. Influenza is an upper (bad colds) and lower respiratory (pneumonias) tract viral infection. It is not a gastro-intestinal infection, although we colloquially say someone with vomiting and diarrhea has “flu” as well; they are not the same infections. Influenza changes its stripes (surface protein antigens) nearly every year, thereby being able to re-infect people who have had flu in previous years. In adults the vaccine is given intramuscularly, or less effectively, beneath the skin, subcutaneously, if anticoagulants might cause too much muscle bleeding. It is a killed vaccine, meaning there are no live virus particles in it, only dead viral cells and bits. Those bits induce your body to make antibodies, circulating influenza virus bullets, over the 2-3 weeks after the shot, so viruses entering your body thereafter are mowed down in large numbers, though not 100%. A few get through and may still cause illness, albeit milder. Children over 2 can get a live virus vaccine in nose drops.
The best way to treat this common disease is to boost your immunity with a flu shot, so you don’t catch it or get only a mild case. The vaccine is reformulated each year, usually with 2 influenza type A variants and one type B by the US Centers for Disease Control, which bases what they tell manufacturers to put in the vaccine on their best guess of which sub-types are around and most infective. The vaccine is egg-based, so the rare person who is truly egg protein allergic (I’ve never met one), can’t take the shot and must use alternatives. Most of us do fine, suffering at most a mildly sore arm. Many claim to have “gotten the flu from the shot,” but this is not possible. Most, I think, are describing a brief aching from the body’s healing up the injection site. Adults and children over 8 need only one dose each year. Children over 6 months and under 8 need a series of 2 shots (or nasal drops if over age 2) at least a month apart if they have never had a flu shot before or have been 2 or more years without one. No immunizations for kids under 6 months; they will have some immunity from their mother still on board from placental transfer and hopefully the family who hugs them all get their flu shots.
The vaccines do work but certainly don’t always prevent infection; in fact you still have a 75% chance of getting influenza, if exposed, even though you’ve gotten a flu shot. But your chances of being so sick you can’t work are reduced to only 60% of what it would have been if you hadn’t had it, because the shot moderates the symptoms. It works even better in the elderly, young, chronically ill (asthma, emphysema, and diabetes) because those groups get much sicker without the shot.
Flu shots cost from $7 in public clinics and some doctor offices, up to $20 at some pharmacies.
And while you are getting your flu shot, consider getting other shots that might make you and your family live longer and/or more comfortably.
First, the combined tetanus/diphtheria/pertussis (whooping cough) killed vaccines as Tdap, where the T indicates an adult dose of killed tetanus cells, the “d” an adequate adult dose of killed diphtheria cells, and the “ap” stands for acellular pertussis proteins without whole dead cells, which cause more side effects. The capital and lower case letters indicate vaccine dose sizes. The disease tetanus, from anaerobic (don’t need oxygen) bacteria that live in dirt, is very rare, <500 cases/yr in the US, but often fatal (60% mortality). The vaccine works extremely well, so it’s crazy not to have a booster every 10 years when your immunity begins to fade. Diphtheria is more prevalent than tetanus but still rare. It used to wipe out whole families before the antibiotic era. Now it’s seen mainly in the alcoholic homeless population. But it is often given with tetanus to try to keep it at bay from everyone. And finally the whooping cough vaccine is important, less for the adults but crucial for infants under 2 years old and to a lesser extent, the elderly, who can also die from it. And we are in the midst of a huge whooping cough epidemic here in Maine right now because our immunity rates have declined. They have declined because many people, especially adults, are not getting boosters, and because the new acellular pertussis vaccine immunity lasts less long, though it has fewer side effects; it replaced the older more potent mercury-preserved cellular dpT. So adults should get a Tdap if they’ve never had an acellular pertussis shot before to protect their very young and old family members and friends, and then a Td subsequently at 10 year intervals. Cost should be similar to the flu shot.
Two other shots are important for older adults. Most important is the Pneumovax shot against pneumococcal pneumonia. People under age 65 need one if they have bad asthma, lung disease, diabetes, or other chronic debilitating disease. All of us need at least one shot soon after age 65, before our ability to respond to it diminishes in our 70s and 80s. Cost is $50-$75. A varicella zoster (the chicken pox/shingles virus) immunization soon after age 60 can diminish the severity and incidence of shingles, which happens more often and causes greater chronic pain in the elderly. Cost should be around $200.
And that’s all, unless you plan to travel to exotic places. Then you should check out travel immunization recommendations for the countries you are visiting at the Center for Disease Control’s very helpful website (http://wwwnc.cdc.gov/travel/).
Dan Onion, MD, MPH
Vienna Health Officer
293-2076
9/19/13