SALT LAKE CITY — Utah children are not receiving the vaccinations they need to combat an array of childhood illnesses, which is leading to an outbreak of pertussis in the state.
The Utah Department of Health this year has reported 875 cases of whooping cough through Oct. 6, most of which are in children. It is the highest incidence of the contagious respiratory illness in the state since 1946.
And the year isn't over yet.
There were 618 cases in Utah in 2011, with 392 of them officially confirmed through specialized laboratory testing. Twenty-four people were hospitalized and one died. The state ranked 35th in the country for immunization rates last year, with 66.7 percent of children fully immunized, according to health department data.
In addition to a decreasing rate of immunizations, the vaccine-preventable disease isn't being prevented because of a waning efficacy of the available pertussis vaccine, said Dr. Andrew Pavia, chief of pediatric infectious diseases at the University of Utah. The factors contribute to recent outbreaks throughout the country.
An abundance of information available regarding a growing number of vaccines has led parents to be confused about vaccine safety, Pavia said.
"It's hard for them to get all the facts," he said. "There's good information and there's bad information, and that confuses parents."
The "information overload," Pavia said, has led to more people being unsure.
"And when people are unsure, they wait, and when they wait, they get behind on vaccinations, and when they get behind on vaccinations, they contribute to the spread of illness," he said. "The best protection is to use the existing vaccine as it is supposed to be used."
In addition to the five-dose pertussis vaccine that children can receive beginning at 2 months of age, the U.S. Centers for Disease Control and Prevention has recommended that adults and children at age 11 receive a booster dose of the TDaP vaccine, which prolongs protection against tetanus, diphtheria and pertussis.
"Adults can get pertussis and full-on whooping cough, and it can be quite debilitating," Pavia said. "So there is a selfish reason as well as the really important reason of protecting the children around us."
A more effective measles vaccine helped keep a widespread outbreak in Utah in 2011 at bay, as the disease infected a little more than a dozen people last year.
Pavia said the state is on track to reach 1,000 cases of pertussis this year.
Epidemiologist Theron Jeppson said pertussis generally follows a somewhat cyclical pattern, with outbreaks every five to six years and no real ability to predict what will happen in the future.
The waning efficacy of the vaccine series, he said, tends to spur an increase in the spread of the disease among 8- to 12-year-olds, as well as a growing and more susceptible younger population.
"Following a year with a big outbreak, we usually see a tailing off, which might indicate that people could have carried a natural immunity through that year," Jeppson said.
The most susceptible of the population are babies, as they are either too young to be vaccinated themselves, or have yet to build up their immune systems to fight off the illness, Pavia said.
"Utah is very fertile ground for outbreaks of childhood diseases because we have a young population, we have big households, and pertussis and other diseases spread more effectively in the close quarters of a house than they do in school or in the community," he said.
While Utah's numbers are high — eighth highest in the country so far — some surrounding states are experiencing even higher numbers, specifically in Washington and Colorado. Minnesota and Wisconsin are also fast approaching epidemic proportions, according to the latest CDC information.
Slowing or stopping the spread of the disease can only be done through greater public outreach efforts, including ensuring that kids complete the dosing series on time — at 2 months, 4 months, 6 months, between 12 and 15 months of age and before kindergarten — and that individuals don't wait on booster doses between age 11 and 12 and again in adulthood, Pavia said.
"These things will reduce the spread of an epidemic like this, but there isn't a silver bullet that will shut it off completely," he said.
Vaccine-preventable illnesses are dependent on high vaccination rates throughout the community, Jeppson said.
"The best thing you can do at this point to protect yourself is to get vaccinated," he said. "It not only protects yourself, but helps keep others from getting sick."
Jeppson said people should also practice "proper respiratory etiquette" and cough into a tissue or on a sleeve, instead of into the air where it can be transmitted to others. Regular hand-washing is important, he said, as well as staying home when sick, to avoid passing any sickness to others.