I have had a great laugh doing some research online (various sites) to try to figure out why this year's whooping cough epidemic is happening in California. It is amazing the amount of misinformation I have found. Pro-vaccine people are blaming it on anti-vaccine people (false, see below), and Anti-vaccine people are blaming it on the vaccine (also wrong). Some people are even blaming it on illegal immigration. As best as I can tell this is because the whooping cough vaccine is different from the vaccines of, say, Polio or Measles, and people try desperately hard to fit it into their agenda even when it doesn't fit. In my reading I have learned a lot about a type of vaccines I never really paid attention to. I figure it's time to set everyone straight.
The NPR article above is particularly laughable (really, NPR does enough good reporting they should know better) because they say whooping cough was once "wiped out." Not so, says the CDC.
Most vaccines against serious illnesses are called "live attenuated virus" vaccines. These include MMR and Polio, and and basically the idea is you give the body a weak version of the virus so it develops an immune response against a stronger version. Usually with appropriate doses, these provide permanent immunity, but there are rare cases where the virus can revert, so it is possible to get full-blown measles from the MMR vaccine, though once again this is rare. These are the vaccines which produce herd immunity.
It turns out that whooping cough vaccine is a different kind of vaccine altogether and in fact individuals are not actually vaccinated against the bacteria that cause the disease at all. Instead, the vaccine is against a toxin that is excreted by the bacteria, and that toxin, called an exotoxin, is what causes respiratory damage. The theory is that this way if you get the illness, your body will have a head start at damage control (by attacking and neutralizing the exotoxin) and so you won't get very sick. So the vaccine is a dose of denatured bacterial exotoxins, called toxoids, that your body can develop antibodies to. Other toxoid vaccines include tetanus and diphtheria. While it is possible to be allergic to an acellular toxoid vaccine like this one, it is entirely impossible to get the disease from it because there are no live (or even dead) microbes in the vaccine itself. Whooping cough, or pertussis, vaccine is usually given with diphtheria and tetanus toxoid vaccines together either as a DTaP or a Tdap depending on age of the individual, but adult vaccinations are rare.
One interesting feature about toxoid vaccines is that they don't actually provide direct immunity against the disease at all because the targets of antibody production aren't on the envelope of the microbe. Instead they work by reducing the severity (and length) of the illness. In short, they don't keep you from getting sick. They just keep you from getting extremely sick. Consequently most people reading this could still get diphtheria this winter, or whooping cough, and could even spread it, but you probably wouldn't know you were carrying a serious illness. In short these vaccines provide absolutely no herd immunity at all, though they may provide some epidemiological benefits in terms of reducing the number of individuals infected by a single person (the downside of course is that it makes diagnosis and monitoring much harder--- we simply don't have any idea, for example, how many minor cases of whooping cough or diphtheria actually occur every year. We just know they don't get sick enough to be diagnosed).
Yet the news media and many "experts" still talk about herd immunity from this vaccine. Indeed while the CDC recommends adults be vaccinated, they state clearly that herd immunity is not a direct factor and that it's not a simple choice.
And while it is not believed that whooping cough has an asymptomatic carrier state, diphtheria is shown to have one, particularly in vaccinated adults. (One possibility worth considering is that asymptomatic means just that, so even mild symptoms, such as those resembling the common cold could be a symptomatic carrier state.)
So the picture that emerges is that whooping cough vaccine prevents death and long, tiring illnesses in children, but doesn't stop the bug from circulating. So it's probably a good thing for kids to have. However, whooping cough is also very much out of control and not just this year, as the CDC admits.
Furthermore I have come to realize that a few times in the last decade I've gotten this cough which lasts a few weeks and then mostly goes away, except for periodic, very heavy coughing, and with no symptoms in between. In these cases, sometimes I have been diagnosed with asthma but the inhalers don't seem to help much (so I go back to using an herbal remedy which seems to work very well, but it is rather non-standard). This lasts a few more months, and then goes away. My current thinking is that my son probably picked up whooping cough at school and I picked it up from him. Since he was vaccinated, he only seemed to have the common cold, but I got something a bit worse.
This specific vaccine isn't about herd immunity, but rather reducing the severity of a serious childhood illness. It doesn't contain microbes, live or otherwise, and while it may reduce the spread of the illness there isn't sufficient data to know the extent of this. This particular vaccine is almost certainly worth giving to most kids. However, there is no benefit that non-vaccinated individuals get from those who are vaccinated in this case.
Whooping cough cycles come and go every few years. This is no different. While hospitalizations may be preventable with the vaccine, it's spread is probably not.