Unlike some other states, no one has died in Utah this year from the disease, which can be fatal particularly for children younger than 1.
Vaccinations are recommended for children, teenagers and adults, including pregnant women. The effectiveness of that vaccine decreases over time, which means teenagers and adults need to receive another immunization. The Centers for Disease Control and Prevention acknowledges that vaccines are not 100 percent effective, but says they do offer strong protection.
In 2010, 27 people died nationwide from pertussis 25 of those were children under a year old.
In Davis County, only about half of the cases this year were among children and teens. Among the adults who fell ill, three were in their 30s, three were in their 50s, and one each were in their 40s or 60s. Health officials believe the end of the school year will slow the spread of the disease, which appears to be on an upward swing in a multi-year cycle.
"With pertussis, it's spread through close contact through droplets from coughing," said Brian Hatch, an epidemiologist with the Davis County Health Department. "That's why school becomes such a place where we see clusters occurring."
Symptoms are similar to the common cold, such as a runny nose and congestion, sneezing and what may be a mild cough. The coughing can become severe after a period of weeks and turn into violent fits that cause people to breathe in with a loud "whoop." However, in infants the cough may be subdued or nonexistent.
An outbreak at a school is more than one case in a defined period of time.
But schools have not been the only places worried about pertussis this year. Some businesses also have contacted the state health department asking how to protect their employees when a colleague or their family member is sick. Adults should not assume they are immune.
"If they've been vaccinated as a child and they're going to be around high risk individuals … they should get a booster," said Theron Jeppson, an epidemiologist at the Utah Department of Health.
What does whooping cough sound like?
Violent coughing fits often have a whoop-like sound. To listen, go to the Utah Department of Health: http://1.usa.gov/alDwaq