Illinois whooping cough outbreak among highest in nation

Pertussis cases near record-breaking numbers across the state


By Dr. Lisa Thornton


There has been a surge of whooping cough across the United States, and Illinois is one of 20 states seeing even more cases than the national average. If the current trend continues, we will see the highest number of cases since 1959, when 40,000 illnesses were reported.

Whooping cough is a highly contagious respiratory infection that moves easily from person to person through coughs and sneezes. It often starts like a cold, but progresses to coughing episodes that are so severe it is difficult for children to catch their breath. The coughing ends with a "whoop" sound as the child gasps for breath, thus the name whooping cough.

Coughing spells may lead to vomiting, choking, difficulty breathing, fainting, sleep problems and even rib fractures. Symptoms usually last 6-10 weeks or more and some children need to be hospitalized.

Whooping cough is caused by the bacteria Bordetella pertussis. Children are routinely immunized against this disease with five injections of the DTaP (diphtheria, tetanus, acellular pertussis) vaccine given at ages 2 months, 4 months, 6 months, 15-18 months, and 4-6 years. Booster doses of Tdap (tetanus, diphtheria, acellular pertussis) are recommended at 11-12 years old and every 10 years thereafter.

The disease is most dangerous in infants under 6 months old, especially those who are preterm or unimmunized. Most of the increase in pertussis is being seen among children 7-10 years old and in early teens ages 13-14.

Health investigators are trying to figure out why the spike in cases.

Theories include better detection and reporting, an evolution in the bacteria that cause the illness, or shortcomings in the vaccine. The vaccine was modified several years ago to make it safer, but the modifications may have made it less effective.

Unimmunized children do not appear to be a major factor in the outbreak since most of the children who develop the disease were immunized. However, when unimmunized children do get the disease they are more infectious, have more severe symptoms, the illness lasts longer and they are at higher risk for hospitalization.

The best prevention is hand washing or sanitizing, keeping your hands away from your mouth, eyes and nose, staying away from people who are ill, and stepping back a few feet from people who are coughing or sneezing.

During a pertussis outbreak, unimmunized children under 7 should not attend school or public gatherings for 14 days after the last reported case. Infants under 2 months are at high risk for getting the disease, so pregnant moms, dads and older children in the home should be sure they are vaccinated to protect the baby.

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