NHL: Mumps Outbreak hits Players and Refs

The National Hockey League (NHL) is currently dealing with a mumps outbreak that has affected at least a dozen players and referees over the past few weeks. Additional players are being tested while the league fears that the disease will continue to spread.

So far, players with the Anaheim Ducks, Minnesota Wild, New Jersey Devils, New York Rangers and Pittsburgh Penguins have all tested positive for the viral infection.

The latest player to be screened for the infection was Penguins forward Beau Bennett. Bennett's teammate Sidney Crosby was seen days earlier with a swollen face, which is one major sign of a mumps infection. Crosby is reportedly past the infectious stage and could return to the team. The outbreak has left many medical experts stumped,

"As physicians, we were caught on our heels by this," said Matt McCarthy, an infectious disease physician for Weill Cornell Medical Center in New York City reported by the Pittsburgh Post-Gazette. "Why is Sidney Crosby - a young, healthy guy with a good response to the vaccine - getting this disease? There's something that's not adding up."

Experts have explained that the effectiveness of the measles, mumps and rubella (MMR) vaccine can wane as time passes. In addition to that, some people simply will not respond to the vaccine. This effect is known as vaccine primary failure, which occurs when the body does not produce enough antibodies in response to the vaccine.

"Right off the bat, when you give it to 100 people, 15 won't respond," Gregory Poland from Mayo Clinic's Vaccine Research Group said reported by Forbes. "Then what happens, if you look at the mumps outbreaks that have occurred in the last 10 years or so, you tend to have lot of young people congregating in close contact - and that's also true in the NHL. Over time, enough [susceptible people] accumulate so that when there is the introduction of the wild virus, it sparks an outbreak."

Mumps is a contagious infection that can spread via contact with saliva, which can be transferred via sneezing and coughing, especially in closed quarters. In this outbreak, the transmission is most likely occurring inside the locker room or on the bench. The infection causes swelling of the salivary glands, fever, fatigue, headache and a lost of appetite. In rare cases, an infection can cause sterility in men and miscarriages in pregnant women.

Mumps was eradicated within the United States in 1967. However, without proper vaccinations, outbreaks can occur. Typically, infants between the 12 and 15-months-old should receive the first dose of the MMR vaccine. The second dose is usually given at the ages of four to six. Adults can also receive booster shots.