MARSHALL - Cases of pertussis, commonly known as "whooping cough," have reached epidemic levels nationally and statewide, but haven't seriously affected Lyon County, so far.
"We clearly have a major epidemic in Minnesota and nationally this year," said Kris Ehresmann, director for infectious diseases at the state Department of Health. "As of July 20, we've had 1,881 cases in Minnesota. To put this in perspective, we look to the peak year. Since the 1950s, that was in 2005 when we had 1,500 cases for the whole year."
Worse, the disease which used to occur mostly in the fall, now occurs year-round.
"There used to be a season," Ehresmann said. "We used to see it in the summer months. We're not seeing seasonality now."
Jo Coover, infection prevention nurse at Avera Marshall Regional Medical Center, said she is not aware of any cases in Marshall.
Public health officials attribute this to an aggressive immunization policy.
"Avera Marshall has been immunizing all of our employees and all patients who come to the emergency room who require and update with TDaP (Tetanus, Diphtheria, acellular Pertussis) vaccine," Coover said.
According to the state Department of Health, there has only been one recorded case in Lyon County to date.
"It may not have gotten here yet," said Kim Jeppesen, state Department of Health regional epidemiologist. "There's been one reported case; we haven't seen a lot in Lyon County this year, as opposed to other years. Reasons could be, one, that it's not here; and two, it hasn't been detected."
According to Jeppesen, the level symptoms for pertussis vary widely from a mild cough to severe enough to require hospitalization, especially for infants.
"Most commonly, people develop a cough, go to the doctor, and it's considered a bronchitis infection," Jeppesen said. "Many times they're given an antibiotic and sent home. It may not be detected till they've had it for several weeks, and by that time it may be getting better. And there is such a variety of symptoms, you can't say it's 'x, y, z,' it varies, which may reflect immunization status."
The pertussis vaccine is usually given as part of early childhood vaccinations and a booster at the beginning of school. But the immunity only lasts for a maximum of 10 years, waning three to five years after the last dose, and the vaccine is only about 80 percent effective, Jeppesen said. However, even if a person with a current vaccination does contract the disease, it is likely to be less severe.
Because the disease can be very severe in infants and young children, the Department of Health recommends parents, grandparents, caregivers and everyone in routine contact with children to get immunized to prevent children from coming in contact with infectious adults, a process health professionals call "cocooning."
"We do see deaths from pertussis in Minnesota," Ehresmann said. "Most recently in 2006, but thankfully we haven't seen it this year. In California in 2010 there were 10 infant deaths."
Treatment for pertussis involves a course of antibiotics to prevent the spread of the disease but mainly support therapy to allow the body to heal itself, according to Jeppesen.
"The thing I want to stress is there is an adult and adolescent vaccine out there, for ages 11 and up," Jeppesen said. "And if a family is welcoming a new baby, everybody in the household should check with a doctor to see if they're eligible for a booster."
Interestingly, health care providers in Marshall were among the first in the state around 2006 to sound the alarm that pertussis is not just a childhood disease and aggressive vaccination among adults and adolescents was necessary, according to Jo DeBruycker, registered nurse and manager of the Affiliated Community Medical Centers clinic in Willmar.
"Now most public health agencies have what we call 'standing orders,'" DeBruycker said. "If you come into the clinic a nurse will assess you to see if you need a vaccination. If you're a child, have you had all five doses? If you're over 11, have you had a booster? If your an adult, do you need a TDaP? Pregnant women should be vaccinated after the 20th month of gestation."