There has been an outbreak of mumps beginning in Nova Scotia and now spreading in Ontario. Accordingly, young adults of university age are the most affected.
The latest outbreak of five people in Ontario in the wake of 222 cases in Nova Scotia has put health officials in top alert.
Public-health officials are now debating whether they need to administer a booster shot, as the latest attacks prove that those vaccinated years ago are getting infected once more.
Ontario's Ministry of Health and Long-Term Care confirmed yesterday that the cases, two of which are in Toronto, are linked to the outbreak in Nova Scotia. The outbreak, which began in late February, has also infected 34 people in New Brunswick and one in Prince Edward Island.
According to Jeannette Macey, head of disease surveillance in the immunization and respiratory infections division at the Public Health Agency of Canada, there may still be more cases as university students, who are most likely to be infected, return home.
Mumps causes fever and swollen saliva glands, but it can also lead to serious illnesses such as meningitis and, in rare cases, sterility in men. The disease is spread through coughing, sneezing, sharing drinks and kissing. It can take up to seven days for symptoms to appear.
Vaccination is the best prevention for mumps, but doctors say young adults in their late teens and early 20s are more prone to the disease because they were born in a period when only one dose of vaccine was administered to children. Since 1996, preschoolers have received two doses.
The agency has recommended that provinces seeing an outbreak consider offering an additional dose of the measles-mumps-rubella (MMR), vaccine to those considered at high risk.
Meanwhile, the National Advisory Committee on Immunization, which advises the country's chief public health officer, will meet next month to review an expanded immunization strategy that targets the vulnerable cohort.
Those infected are asked to isolate themselves at home for nine days. According to Neil Rau, an infectious disease specialist at Halton Healthcare Services in Ontario, the current strain of mumps originated in Britain, where there was a large outbreak in 2004. Immunization rates had dropped significantly in Britain because many people believed the measles-mumps-rubella vaccine caused autism. The vaccine-autism link has since been disproved, experts note.
The disease reached Iowa last year, and Rau says it has now found its way into Canada.
'It's global travel compounded with vaccine refusal,' he stresses.
Dr. Rau is of the opinion that it's difficult to predict how long this disease will last and how far it will spread. About 30 per cent of people who have the mumps show no symptoms.
'It definitely seems to be confined to the university-age population so far,' he said. 'There's no question we will see more cases in Canada as students return home.'
Nova Scotia is starting a mumps immunization program for health-care workers.
The immunization program will begin as early as next week with roughly 40,000 doses of the MMR vaccine being made available to health-care workers.
Dr. Shelly Sarwal, the province's medical officer of health, says the vaccination program will help the maintain health services in the province.
'We feel this is an important public health measure,' Sarwal was quoted. 'A vaccination campaign will not stop the outbreak, but what it will do is help to manage absenteeism in health-care workers as a result of the mumps, and therefore help sustain the health-care system for Nova Scotians.'