One of the Herd
Sometimes, sticking out from the crowd is great. Why do you think I have this hair? But other times, being unique isn't so great. You just want to blend in and be like everybody else. One of the herd. Apart from anything else it's good for your health.
In South Wales at the moment, being part of the herd is a very good thing. A media panic about the MMR vaccine 15 years ago caused a drop in vaccination rates, and what we call herd immunity. Now the people of Swansea are suffering for it. As of Friday, in the last 6 months there have been 903 new cases of measles in Wales, and 648 of those have been since the beginning of March this year. And even as you're reading this, that figure will have gone up. Most are either in the 10-14 age group, who would have been due their MMR jabs right after the scare, or the 0-4 age group who may be too young to have the vaccine now.
The thing about vaccination is, it doesn't just protect you. It also protects the people around you who can't have the vaccine, such as very young children and people with chronic illnesses that weaken their immune systems (for instance, people having chemotherapy). These people rely on being protected simply because everyone around them is vaccinated, so if a carrier or infected person comes into contact with them, they're in trouble.
Here's a good video that explains herd immunity from Aussie medical group Chain of Protection:
We need vaccination rates to stay high to keep the whole community safe. For instance, you need about 80-85% of the population to be vaccinated against polio to stop it cropping up again. The vaccination rate for MMR is much higher, closer to 95%, as measles is incredibly infectious. But the vaccination rate in some parts of the UK is way below that, for instance 86% in South Wales, and reported as just 70% in Totnes, Devon.
Why are some people so scared of vaccinating their kids? There are lots of misconceptions, even away from the false autism scare that's causing havoc in Swansea now. Some people believe that multiple vaccinations somehow overload their children's immune systems and cause them to "be overworked", but there's absolutely no scientific evidence that the body can't handle it. Studies have shown time and time gain that the multiple vaccines used worldwide cause no more extreme reactions than single vaccines. In fact, single vaccines do more harm, simply because people are less likely to go back for the rest if they "spread out" the time between jabs. Life gets in the way.
Some people believe that there's no need for vaccination because improved hygiene and health standards have all but wiped out the nasty diseases of yesteryear. Wrong. The WHO reports that deaths by measles went down by 75% as a direct result of vaccination programmes. We can see the effect of vaccination on the population by looking at the incidence of chicken pox in the USA. The chicken pox rate was still as high as ever until the mid 90s when vaccination was introduced... surely people were living hygienic lives by then? We're hardly talking about an Age of Squalor and Deprivation.
It's really quite simple. If we stop vaccinating, the diseases come back.
Why aren't our own natural defences enough?
As the problem in South Wales shows, sometimes it's best to give them a helping hand. All multi-cellular animals, from fire ants to elephants, have defences against disease-causing viruses and bacteria (called pathogens). Non-specific immunity covers the things your body can do to stop a pathogen getting into you in the first place. There's a whole bunch of stuff, from that extra big sneeze you did when the pepper lid fell off at dinner, to the time a bug flew into your eye and it watered for hours, right through to the fact you have skin.
Specific immunity is where things start to get fun. Should a pathogen manage to break through the obstacle course of your primary defenses they have to fight your white blood cells, which you might have heard of (if only as the name of a great White Stripes album). The white blood cells (called phagocytes) basically perform what I like to think of as an "omnomnom" function, embracing and gobbling up any pathogen that passes by.
But phagocytes can't deal with everything. Sometimes we need something special for particular pathogens, and that's where the lymphocytes come in.
Despite sounding like something from beyond the wall in Game of Thrones, the lymphocytes are very much in our side. They're created in our bone marrow and form mainly two types, T cells and B cells, which work as a perfect team.
B cells are excellent at maturing into different kinds of specific pathogen-fighting machines. For instance, if you get chicken pox your B cells will multiply into blood cells that produce chicken pox anti-bodies. But your B cells aren't that good at detecting if something is there in the first place. Most of the time they're dormant, and only multiply and specialise when a specific pathogen like chicken pox enters the body. The job of the T cell is to sound the alert.
The T cells sound the alarm when a particular kind of white blood cell called the Antigen Presenting Cell shows up with a bit of the problem attached to it. They spring the B cells into action, and also make some Killer T cells of their own which recognise infected body cells and zap them. It's also the T-cell's job to calm things down, stop things multiplying and end the attack when they sense the job is done.
But even when the infection is over and the B and T cells subside, "memory cells" remain in case that pathogen ever crops up again. And this is why vaccination works. It introduces a weakened or inactive version of the pathogen so that if the Real Thing pops up, your body can swing into action with those memory cells that have just the antibody you need.
Make no mistake. vaccination works, and it's vital to the health of both us as individuals, and the populations we live in. We've eradicated smallpox, and we're working hard to eradicate polio. But as the people of South Wales are learning, if we want to eradicate these nasty diseases it's a relentless job. The slightest chink in the armour of vaccination and they return. There's no treatment for measles once you have it, you simply have to let it run its course. And while for most people that will be a nasty rash and a temperature, it can be a lot more complicated than that for some.
Measles is NOT marvellous. It kills about 400 000 people across the world each year, and about one in five will have one or more complications - from diarrhoea to blindness and heart disease. Between 1 in 2500 and 1 in 5000 will die from it, the highest proportion being among the under 5's.
I'm going to leave you with a link. Go and read this passage from Roald Dahl, whose daughter Olivia died of measles at 7.
Because nothing can be more powerful than the words of someone who has lived it. There was no reliable vaccine for measles in Olivia's day. But there is now.
No more deaths from something we can treat so easily. Please.
Be one of the herd.