Friday, April 18, 2014

Being against vaccines is like being against seatbelts

I sometimes try to come up with analogies that can help people understand the benefit of vaccination. One that I believe ought to used more often is the seat belt analogy. Although most parents in Sweden do vaccinate their children according to the national program there are some who believe that the potential risks of vaccination outweigh the benefits.

Admittedly, un-vaccinated children usually do fine in Sweden, thanks to good compliance with the vaccination programs in the past. There are in essence not so many viruses left in Sweden and therefore it is unlikely that you get vaccine preventable disease even if you decide not to vaccinate. It does happen however, that children get for instance measles. (It is extra common in Järna where I grew up due to the widespread false and silly belief that it aids the childs mental development .) However, because our health care system is relatively good it is also very uncommon that children die or get permanent disabilities as a result of measles. Rather, most parents come away with a feeling that measles is really not that bad... Ok, so un-vaccinated children are unlikely to get sick and even if they do get sick it is unlikely that the disease will have any severe consequences. So why vaccinate at all?

The simple answer is that not vaccinating is a huge risk compared to vaccinating which is associated with almost zero risk, and this is where the analogy comes in. Would you accept the argument that we should stop wearing seatbelts. After all, most people have tried this and nothing happened to them. It might even be that on rare occasions the seatbelt prevented a person from exiting a burning car or the metal thing at the end of the seat belt caused a burn on a child... I'm sure

Shouldn't we stop using seat belts? This argument is I believe almost perfectly analogous to the vaccination argument. Of course, as most people realize in the seat belt situation (but not in the vaccination situation), an anti-seat-belt policy would cause many thousands of deaths because even though most people manage fine without seatbelts. This is because the small proportion of people who actually would have been saved by vaccination, I mean seatbelts, adds up to hundreds of thousands of people.

Just to really drive home this message, think of the many people oppose the relatively new HPV vaccine. The HPV virus, which the vaccine protects against, is responsible for approximately 200.000 mortal cases (from twice as many cases), of cervical cancer per year. The vaccine meanwhile have been tested repeatedly with no adverse effects discovered to date. How many years should we keep on testing before we decide that the evidence is sufficient to go ahead and save 200.000 lives per year?

No comments: