A simple overview of vaccinations.
There is currently a scheme in Wales where GPs and pharmacists are working together to try and get more people eligible for the flu vaccination to have it (as reported in the news here). Seeing this made me happy, because I’m all for a good vaccination if it is useful and necessary, as the flu vaccination is for those who are most susceptible to catching flu (mainly the elderly). Then I realised that I haven’t yet written a post on vaccinations, so I’m rectifying that since talking to family and friends often makes me realise that quite a lot of people have either a too simplistic view of injections or a wildly incorrect one.
Many people understand that vaccines are a form of a disease which is injected into the body to help protect a person against the actual disease. This is all very true, but it can give people misconceptions about just what an injection is. I have spoken to people who refuse to get an injection (such as the flu jab) because they don’t want to get the disease when they currently are free from it. Alternatively, there’s the anti-vax movement who push scare stories about vaccinations not being ethical or safe. One of the most famous of these stories was the supposed proof that the MMR vaccine led to Autism in children, which is actually incorrect (as I write about in this post).
To understand why vaccines work, it is useful to have a brief idea of how the cells of the immune system respond to disease. Essentially, there’s the primary response and the secondary response. The primary response is what happens when you first encounter a new disease. The cells of the immune system have to divide and produce enough cells with the correct antibody to destroy the disease. This takes time, and so you show all of the symptoms and get sick. The secondary response is when you encounter a disease your body is already familiar with. As you have had the disease before, memory cells in your immune system already know what the correct antibody to use is, so they produce them rapidly and you don’t get sick. Voila! The immune system is a wonderful thing!
Just think of it like the playground riddles children tell, found on the back of food wrappers or in puzzle books. The first time you hear the riddle, you spend a good long while thinking about it and pondering over what the solution might be. The subsequent times you hear the riddle, you already know the correct answer and so it takes less time to answer and the amazement and novelty of how cunning the riddle is has worn off. That’s basically how the immune system responds to disease, on a simple level. The first time the disease is a puzzle, the second time it already knows which antibody is the correct answer.
This is why vaccinations are such nifty little things. You are preparing your body to be able to fight the actual disease without chancing when you will catch it. By having the injection, your immune system can fight the disease and so when you actually come into contact with it the memory cells already know which antibodies are needed in the situation. So you don’t get ill at all. Why not? Because the vaccination contains a weak or dead version of the disease which you are being protected against. Therefore when it enters the bloodstream it is still recognised as dangerous by the immune system, but it cannot actually seriously harm you. All it serves to do is act as the stencil by which the immune system designs the antibodies which will fight any real versions of the disease which you come into contact with. This is also where the idea comes from that if you catch something once, you won’t catch it again.
Now, that isn’t strictly true, as I’m sure most of you guys will know. Everyone knows a friend of a friend who had the flu jab then still got the flu, or got measles twice in their lifetime. This is because of variation within the disease. Technically, flu isn’t just a single disease, it is many variations of one. These all have different antigens on their surface, and so all require different antibodies. Therefore, only the version you have previously had (or have been injected against) will be the one you are protected from. You are still able to catch the others. But why not just vaccinate against all flu strains? Well, it just isn’t possible. One: there are way too many strains to reasonably vaccinate against them all. Two: flu is constantly evolving. It changes continually to try and combat the resistant populations having their flu jab. Therefore, we just couldn’t vaccinate fast enough to keep up with it.
The next question people have is most likely what’s the point in having the vaccination at all then? The answer to that is that having the injection makes you more likely to not get it the year you have the injection. Every year the flu jab changes, as scientists create a vaccination against the most common type of flu that is going around that year. Therefore, if you do have the flu vaccination and still get the flu, you’ve caught one of the less common strains for that year. By having the flu jab every year if you are told by your GP or pharmacist that you’re vulnerable to infection, you are giving yourself the best chances of not being infected at all. Think about it like this: If I strain my pasta using a colander to get the water out, only a couple of the really small pieces are likely to slip through the holes compared to if I just tried to tip the water out of the pan with nothing present to catch the majority of the pasta. If I’m vulnerable to the flu and I get the injection that’ll catch the biggest chance of infection, I’m better off than if I had no protection at all.
Also, people can have a disease once (perhaps in childhood) then get it again later on in life. Or they can be vaccinated against a disease then still catch it later on in life. This is because memory cells do not store the information forever when there are different infections to fight. Think back to the riddles I mentioned earlier. If you are asked the same playground riddle when you are much older, by a child that has just heard it, you may indeed have forgotten the answer. Since you first heard it you have had other more urgent things to remember. This is why vaccinations and booster vaccinations are so important. There’s no point in saying “well I had that vaccination once so I won’t bother with the boosters, it’s just doctors wanting something to do” or “I don’t need that vaccination as I caught that when I was younger.” You need the boosters to keep your immune system memory cells producing the antibody. You’re essentially tricking your immune system into thinking that regular infection by the disease is likely, and so are keeping it producing the antibody. If somebody had asked you the same riddle once a month for your whole life, you wouldn’t forget the answer. So every few years you should get your booster vaccinations to ensure that you’re still protected against disease.
I appreciate that vaccinations are a scary prospect for some people, who have phobias of hypodermic needles. This is why I am so interested in a recent publication which is another look at how vaccinations (such as those for flu) could be made more accessible to all by a new technology being developed. Scientists are in the early stages of trialling skin patch vaccination methods. Basically, plasters with a patch of tiny needles on which dissolve into the bloodstream through the skin. Early phase trials suggest that the method is much less painful and similarly effective. Obviously, these are still in the early phases of development, and so it will likely be years before they are available (if indeed they do pass all clinical testing trials), but the prospect is certainly an exciting one. These could prove useful not just for those unable to get to a health centre or who are afraid of needles, but for less well developed countries where disease outbreaks are highly likely and a quicker way of administering vaccinations would surely be invaluable. I’m certainly looking forward to seeing where the idea goes.
So, in summary: vaccinations are necessary for us to remain immune to potentially life threatening illnesses. They aren’t just a way of health professionals keeping us in check, and the main scare-stories surrounding them are (in my opinion) outweighed by overwhelming evidence in favour of being vaccinated. At the end of the day, my main goal here was to help you get a better understanding of vaccinations. So I hope now you feel you know enough vax facts to go and get your booster jabs done.