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Rich Pedroncelli, AP
An empty bottle of Tetanus, Diphthera and Pertussis, (whooping cough) vaccine is seen at Inderkum High School in Sacramento. Calif.
We can't predict if it will get any worse, but we're continuing to get reports of it and it's still going strong. —Rebecca Ward, a health educator with the Utah Department of Health's Bureau of Epidemiology

SALT LAKE CITY — Utah is on track to double last year's number of pertussis cases and winter hasn't even officially begun.

With various holidays on the horizon, families and other groups of people will be gathering together indoors, which might be cause for concern if someone is sick.

Colder months are typically high time for virus-spreading, including the pervasive whooping cough disease, which seemingly has a particular hold on young kids this year. Already, it has infected 641 children under the age of 14, including 103 babies, according to Utah Department of Health data.

"We can't predict if it will get any worse, but we're continuing to get reports of it and it's still going strong," said Rebecca Ward, a health educator with the Utah Department of Health's Bureau of Epidemiology. She said even with all the public education and outreach efforts, the number of cases continues to climb.

There have been 1,108 cases of pertussis reported to the department so far this year. It is the highest year on record, with 2008 coming in second with 807 total cases that year, according to health department data.

At this same time in 2011, there had been 527 people infected, and last year rounded out with 618 total cases across the state. The most populated counties in Utah are the most affected, with southeastern and northwestern counties reporting far fewer cases.

As of October, 48 states had reported higher numbers this year than in 2011, according to the U.S. Centers for Disease Control and Prevention. Wisconsin, Minnesota, Washington, Vermont, Montana, Maine, Iowa and North Dakota have a higher incidence of pertussis than Utah. Several surrounding states, including Colorado, have reported much higher rates than double what was reported last year.

Speculation about vaccines could be partly to blame, as many parents are choosing not to have their children immunized, Ward said.

The health department cautions about the waning efficacy of the initial vaccine, which is said to not provide full immunity without a one-time booster dose of the Tdap vaccine, received between ages 11 and 12, or as an adult. Vaccinating on time is another issue that is important for maintaining immunity levels in children, Ward said.

Perhaps the biggest impact of such an outbreak of pertussis — which is merely annoying for adults with the sickness — is felt by public health investigators.

"A lot of resources go into finding out who is affected and how we can mitigate the problem," Ward said. Schools and child care facilities are often faced with the question of whether to exclude certain kids from daily activities in order to protect others in the same environment.

The state has recently adopted standard pertussis outbreak guidelines, including an option for school districts to send letters home to parents informing them of pertussis detection at the school. It is an attempt to curtail the spreading of the rampant disease.

"It's important to inform the public of the situation until there is no threat," Ward said.

Epidemiologist Valerie Vernon said the letters determine who has been exposed to the illness, which students might be symptomatic, based on observations, and sometimes the letters include a provision that unvaccinated children be kept home.

Vernon said several school districts have taken that route, with Utah and Iron counties being the latest. An outbreak, she said, is the confirmation of two or more cases within 20 days of each other at the same school. At that point, parents are often notified.

"We want to make sure parents are aware that pertussis is going around, especially for those kids who aren't vaccinated," Vernon said. The biggest concern is children and adults who might take the virus home to their infant siblings.

"In any pertussis outbreak, it is important to protect infants under the age of 1, who have not had a chance to develop full immunity and are at the highest risk for severe complications," Vernon said. Babies who contract pertussis can end up hospitalized, on ventilators or even dead from the sickness.

"In adults, it is not as severe," she said. "It may seem like a cold or a nagging cough, but it is pertussis and it is spreading to their kids."

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