Mumps outbreaks mean we all have work to do

Recently, public health officers in Toronto announced an outbreak of mumps clustered around bars in the city’s west end. This follows outbreaks last year in Whistler, last month in Halifax, last week in Medicine Hat, and last month among several of the Vancouver Canucks. For a disease most people thought was history, there seems to be a lot of it around. The comeback of this obscure relic teaches us that when it comes to public health, we still have a long way to go.

Mumps is caused by the mumps virus, which comes from the same family as measles. Most people who catch it experience about 10 days of fever, pain and fatigue, followed by a trademark swelling of the salivary glands. There is no treatment other than managing the symptoms. For most people these symptoms are minor and short-lived.

Unfortunately, in rare cases, mumps can give rise to serious complications, especially meningitis and hearing loss. Males can experience painful swelling of the testicles, and women the ovaries; for men this can damage fertility. Worse yet, mumps is highly contagious. The virus is transmitted by droplets from coughing, saliva or direct contact, so even sharing drinks or cutlery can pass it on.

So why is mumps coming back now? There are at least three reasons.

First, our policies have changed. Before the late 1960s, there was no vaccine for mumps, which meant most people developed immunity the hard way, by getting sick. From 1970 to 1996, children were given a single shot of mumps vaccine and rates dropped massively. Research started to show, though, that two shots gave better protection than one, so in 1996 Canada’s policy changed.

However, many people born between 1970 and 1996 have “incomplete” vaccination coverage, though most don’t know it. Further, there’s some debate about whether the current vaccine is effective enough against all strains of mumps. Curiously, it seems to protect well enough day to day, but less so during sporadic outbreaks.

Second, when outbreaks happen, doctors notify public health agencies, and guidelines say people should “self-quarantine” for five to nine days.

But beyond these straightforward pieces of science policy lies the messiness of the real world. Mumps thrives in situations where people have their guard down such as locker rooms and night clubs. Asking people to self-quarantine is always going to be difficult, especially if they think their friends all have been vaccinated.

Third are the factors nobody can anticipate. For mumps, that came in the anti-vaxxer controversy. The virus is one of three covered by the MMR (measles, mumps, and rubella) vaccine. This is the vaccine that a fraudulent and discredited scientist once tried to connect to autism. His findings have been debunked, but the damage was done. Cases of mumps spiked massively in the aftermath, and will continue to as the virus continues to find unprotected populations in which to thrive.

Viruses have social lives. A vaccine alone can’t win against the massed forces of history, culture and politics. A whole social world needs to support that vaccine, long after the virus has slipped from memory.

As much as we’re making progress against some of the biggest challenges in medical science, the nuts and bolts are still desperately important.

Many Canadians are learning the hard way that as much as cuttingedge research takes the headlines, the unglamorous, shoe-leather work of public health affects them in concrete ways.

And it turns out there’s still quite a lot of that work left to be done.