Ryan Suter recently joined Minnesota Wild teammates Keith Ballard, Marco Scandella, Jonas Brodin and Christian Folin, Corey Perry, Clayton Stoner and Francois Beauchemin of the Anaheim Ducks and Tanner Glass of the New York Rangers to be diagnosed with the disease.
Those infected with mumps can have a fever, headaches, muscle aches, fatigue and loss of appetite, followed by the swelling of salivary glands, according to the Centers for Disease Control and Prevention.
Deputy commissioner Bill Daly said the league has been in contact with team doctors and training staffs about best practices to prevent the spread of mumps, which has caught everyone off guard.
"It is certainly an outbreak that was unexpected and has caused unwanted disruption at the team level, but it is not something we have any significant control over," Daly said. "As long as our clubs are doing what they need to do to minimize risk of contraction, we are hopeful that the wave of cases will run their course and life will return to normal in the relatively near term."
Nine out of some 600 players getting the mumps is not a full-fledged epidemic, but the lack of familiarity about mumps has made it a talking point around the league. As Wild star Zach Parise joked to the Star-Tribute in Minneapolis: "What is this, the Oregon Trail? Where are we right now? Every team seems to get the flu once a year, but the mumps?"
When Perry and Beauchemin were ill and eventually tests showed they had mumps, the NHL/NHLPA joint health and safety committee began working with teams to prevent further spread.
"The NHLPA has been actively educating the players regarding the recent outbreak, while providing best practices on how to avoid contracting and spreading mumps," spokesman Jonathan Weatherdon said.
The mumps virus is spread through saliva or mucus, usually from coughing, sneezing or talking, according to the CDC. Sharing drinks and utensils can also contribute to spreading the infection.
"It's something we're aware of," Vancouver Canucks NHLPA representative Kevin Bieksa said. "The PA's addressed it, we've sent out a couple emails with some of the symptoms and some of the warning signs. Most of us have been vaccinated, so we're doing whatever we can to prevent it."
The Canucks aren't the only ones taking precautions. Rangers coach Alain Vigneault told reporters that his team would be getting booster shots after they found out Glass had the mumps.
According to the Winnipeg Free Press, the Jets have told their players not to share water bottles or towels and have been disinfecting dressing rooms when on the road.
The first mumps vaccine was licensed in the United States in 1967, according to the CDC. The measles-mumps-rubella vaccine began to be administered in Canada in the early 1970s, according to the Public Health Agency of Canada.
Originally, one dose of the MMR vaccine was administered to a child aged between 12 and 15 months. In 1989, several health agencies recommended the vaccine be increased to two doses, the second given between ages 4 and 6.
The CDC says two doses of the vaccine are 88 per cent effective at preventing mumps, while one dose is 78 per cent effective.
There's no one common theme to the spread of mumps in the NHL, as the nine players range in age from 21 to 34 and are of three different nationalities. Suter (born in 1985) and Ballard (1982) are American; Perry (1985), Beauchemin (1980), Stoner (1985), Scandella (1990) and Glass (1983) are Canadian; while Brodin (1993) and Folin (1991) are Swedish.
Even though he got vaccinated, Bieksa acknowledged being taken aback by news that mumps is going around.
"Obviously when there's a little bit of a small epidemic in the league, you kind of get concerned," he said. "We played a lot of those teams (like) Anaheim, when they were going through it."
Each new case brings more conversation about the mumps virus. Bieksa knew about the cases with the Ducks and Wild but hadn't heard of Glass getting it.
Told the league couldn't anticipate this outbreak, Bieksa said: "And rightfully so. Who would expect us to have the mumps?"
A look at the NHL players who have contracted mumps and how many games they missed:
Keith Ballard, Wild: 8 games
Jonas Brodin, Wild: 7 games
Christian Folin, Wild: 5 games
Corey Perry, Ducks: 5 games
Francois Beauchemin, Ducks: 5 games
Clayton Stoner, Ducks: 5 games
Tanner Glass, Rangers: 3 games
Ryan Suter, Wild: 2 games (Ongoing absence)
Marco Scandella, Wild: 2 games
Follow @SWhyno on Twitter