There has been an alarming increase in the number of cases of mumps and other childhood diseases in recent years, but it's taken a few millionaire hockey players to get infected – notably superstar Sidney Crosby – for the rest of us to take notice.
If that's what it takes to remind us of the importance of vaccination, and how we take it for granted at our peril, then so be it.
As of Monday, 14 National Hockey League players and two off-ice officials on four different teams had been officially diagnosed with mumps. That is almost certainly a fraction of the true number of cases.
A widely circulated photo of a puffy-cheeked Mr. Crosby fit the classic mumps image, but, in fact, fewer than half of people infected with it suffer noticeable swelling of the parotid glands. The mumps can be difficult to diagnose.
What's fascinating about Mr. Crosby's case is that he was reportedly vaccinated. Officials with the Pittsburgh Penguins said he received the MMR (measles-mumps-rubella) vaccine as a child and a booster shot before travelling to the Sochi Olympics earlier this year.
Vaccines work by stimulating the immune system to create antibodies, but they're not 100-per-cent effective. That's why it's important for everyone to be vaccinated, to create what's known as herd immunity.
The reason healthy young men like hockey players are getting sick from preventable illnesses like mumps is that too few people are vaccinated, allowing the virus to circulate widely. What should concern the public about this outbreak is not just the health of pro athletes, but vulnerable members of the community: Hockey players are frequent visitors to children's hospitals, particularly in the holiday season, and mumps can be life-threatening to kids with compromised immune systems.
Anti-vaccination activists – a tiny, loud minority – have a lot to answer for, but so too do the growing numbers of those who are simply misinformed or indifferent to immunization's benefits, and overstate its risks.
The NHL infections are also an important reminder that mumps isn't just a childhood illness any more. In fact, those at greatest risk are young adults (like Mr. Crosby) born between 1980 and 1996 – the reasons for this are simple enough, but the details are important for those who want to protect themselves.
Immunization against mumps began in Canada in 1969 (and 1967 in the United States) but the disease still circulated fairly widely until 1980, meaning that most children were exposed and developed natural immunity. Some anti-vaxxers are proponents of letting kids get infected with childhood diseases so they can develop natural immunity, but let's not forget that pre-vaccine, mumps killed a couple of kids a year and was the leading cause of deafness and infertility in males. (In some cases, the virus can cause meningitis, a life-threatening swelling of the brain, or orchitis, a swelling of the testicles that can lead to infertility.)
Children of Mr. Crosby's generation received only one shot of the MMR vaccine, which is effective somewhere between 62 and 91 per cent of the time. Starting in 1996, children started getting a second shot of MMR, which increased effectiveness to 76 to 95 per cent.
That's why young adults born in that 1980-1996 time period (and some public health officials say 1970) are urged to get a booster shot, especially if they live and work in communal settings or travel a lot, which describes the lifestyle of hockey players, postsecondary students and military personnel.
But even the mumps booster is not 100-per-cent effective, especially if there is a lot of virus circulating and a person is exposed often – as they would be if they are hanging out with a lot of 19-to-34-year-olds, which is precisely the NHL demographic.
In Canada, we have gone from almost 50,000 cases of mumps a year in the prevaccination era to almost eliminating the disease, with a low of 28 cases in 2003.
Now, we're back to several hundred cases a year (and several thousand in the United States), most of them tracing back to student campuses or sports teams, where the undervaccinated are rife.
In addition to the health issues, we should not forget that infectious diseases are costly to the economy because they force the infected and their caregivers (often parents) to take time off work.
Proper vaccination costs a few dollars – or in the case of mumps, a few pennies – but illness costs a lot more. In Mr. Crosby's case, mumps cost his employer the services of someone who's paid $146,341 a game.
Sid the Kid isn't a kid any more but then, mumps isn't a kid's disease any more, either.