Mumps

Mumps used to be common, but these days, cases are rare. In the early 1950s, approximately 34,000 Canadians would come down with mumps each year. By the late 1990s, the number of annual cases had fallen by 99 per cent to fewer than 400.

The number of cases dropped to an average of 87 between 2000 and 2004.

Widespread vaccination programs have all but eliminated what once was a common childhood disease.

But in recent months, concern about mumps has resurfaced as an outbreak that began in Atlantic Canada gained momentum, spreading to Toronto and Alberta.

Well over 300 cases surfaced in Nova Scotia, New Brunswick and P.E.I. in May alone. Nova Scotia has been hit hardest since the outbreak surfaced there in February. The province had reported 302 cases by May 25 - mostly among university students. More than 100 hospital workers in the province were forced to take paid leave after testing positive for exposure to mumps.

What is mumps?

Mumps is an infection of the salivary glands, caused by the mumps virus. It usually affects children between the ages of two and 12, but can also affect other age groups, though infection among those over the age of 40 is rare.

The disease is contagious, spread though direct contact with respiratory droplets, saliva or contact with any contaminated surface.

The disease may involve fever and swelling of the salivary glands in the neck just below the jaw line.

What are the symptoms?

The most common symptoms include:

• Swelling of the salivary glands on one or both sides.
• Pain behind the lower jaw when chewing.
• Fever
• Headache
• Sore throat

How is it treated?

In most cases, you have to wait until the disease runs its course. It's recommended you stay away from school, work, public places and other social settings for nine days from the onset of symptoms so you don't infect anyone else at risk. Carriers are also contagious for about seven days before the onset of symptoms.

If you're experiencing pain, acetaminophen may help reduce discomfort. You can also apply either heat or ice to a swollen neck.

Can there be complications?

In the vast majority of cases, mumps is a minor illness that causes a couple of weeks of discomfort. But it can produce some significant complications.

Post-pubescent males may experience a painful swelling of the testicles. This happens in 15 to 20 per cent of cases in that group. In very rare instances, some men can become sterile from the infection.

Other complications in people who become seriously ill from mumps — again, very rare — can include encephalitis (infection of the brain), meningitis (a swelling of the covering of the brain), arthritis and deafness.

Is it preventable?

Absolutely. In 1969, the federal government approved use of the MMR (measles, mumps, rubella) vaccine. By the early 1970s, it was available in free programs across the country. Health Canada recommends that all children receive a first dose of the vaccine by the age of 12 months and a second dose at least a month after the first dose — or before the child begins school.

Clinical tests have found that one dose of the vaccine can be 95 per cent successful in preventing the disease. But the Public Health Agency of Canada says the success rate for a single dose of the vaccine may be as low as 80 per cent.

Since the mid-1990s, most Canadian jurisdictions have moved to a two-dose regime.

Jeannette Macey, the head of disease surveillance with the PHAC, said the 2007 outbreak that started in Nova Scotia stems from waning immunity among people in their late teens and early 20s. She says young people who did not return for a second "booster" vaccine — or missed the vaccination altogether — are the ones fostering the new outbreak.

"It actually takes a number of years for a few people missed in each age group to accumulate to the point where you actually have enough of a subpopulation to feed an outbreak, and this is exactly what we've seen here," Macey said.

Are outbreaks common?

Not very. There have been five in the past decade. The 2007 outbreak has been the largest in recent years.

There has been a continuing outbreak in the United Kingdom that began in 2004 and has produced about 70,000 cases to date. The disease remains common in parts of the developing world. The mumps vaccine is used in only 57 per cent of countries that belong to the World Health Organization.

What should I do if someone in my home has mumps?

If you've already had the disease, you should not need to worry about becoming infected again. You are likely immune. But, if you haven't had it yet, there are several steps you should take. Among them:

• Avoid direct contact with the infected person, including sharing saliva. No kissing.
• Wash your hands often or use hand sanitizer.
• Avoid shared drinking glasses or eating utensils.
• Cover your mouth when you cough or sneeze with a tissue or your elbow.