Story URL: http://news.medill.northwestern.edu/chicago/news.aspx?id=106273
Story Retrieval Date: 5/25/2013 11:22:55 AM CST
The outbreak was first announced Nov. 11. An outbreak occurs when more than one person not living under the same roof is infected.
Five cases in the Evanston outbreak have been confirmed by laboratory testing, the other five are “epi-linked,” meaning they have been in close contact with infected persons, had symptoms and were treated, but are not tested, said Margaret Mathias, communicable disease specialist in the Evanston Health and Human Services Department.
Mathias said all lab-confirmed cases are in children aged four to 12. Four of the five additional cases are parents of those children, and the fifth is a sibling.
The children attend school in Evanston and Skokie’s District 65, according to a district spokeswoman.
“We had at least one case at one school and then several at another school,” said district communications director Patricia Markham. She declined to say which. The district’s health code requires that all entering students be properly immunized, barring religious exemptions.
Letters have been sent home with all students in the two schools, with additional letters sent to those who have been in “close contact” with the infected students, Markham said. The CDC recommends that those who have been in close contact be treated with antibiotics, even if they have been immunized.
Whooping cough, formally known as pertussis, is a highly contagious bacterial infection involving the respiratory tract that causes prolonged coughing illness, according to Dr. Amanda Cohn, of the Centers for Disease Control and Prevention in Atlanta.
“It causes, especially in young children, a very characteristic cough–uncontrollable coughing often followed by a whooping sound or vomiting after the cough,” Cohn said. Coughing can last anywhere between six weeks and three to four months, even after treatment with antibiotics, she said.
Pertussis is transmitted through direct contact with the bacteria discharged from the nose and throat of an infected person, or when an individual breathes in droplets expelled when an infected person coughs or sneezes, according to the Evanston Health Department.
Infants less than 12 months are most susceptible to pertussis complications, which include pneumonia, middle ear infection, weight loss, dehydration, seizures, rib fractures and death, according to the department. Ninety percent of infants who contract the disease are hospitalized, according to the CDC. Earlier this month, an infant in southern Texas died from pertussis, state health officials confirmed.
But, according to Cohn, pertussis is sometimes difficult to detect in children. “Often it seems like another common cold with a cough, which kids get all the time,” she said. She advised parents to take their child to the physician if he or she has been coughing for longer than one week, especially if the coughing seems out of proportion with their other cold symptoms.
“Vaccination is the best way to prevent your child from getting pertussis,” Cohn said. While you can still get the disease if vaccinated, it will be much less severe, she said.
Pertussis vaccine is administered as a five-dose series: at two, four and six months of age, and again between 15 to 18 months and four to six years. The five-part immunization protects people from infection 85 percent of the time, according to Cohn. A one-time pertussis vaccine “booster” was developed in 2005 and is often given along with the tetanus and diphtheria booster shots (Tdap). The CDC now recommends the pertussis booster for adolescents and adults.
There have been five pertussis deaths in Illinois since 2003, according to Melaney Arnold, Illinois Department of Public Health spokeswoman. Approximately 300 cases of pertussis have been reported so far this year in Illinois, she said. Evanston has had just one previous case this year.
“Every year the numbers fluctuate and sometimes it’s cyclical,” Arnold said. A CDC report stated that incidence has risen steadily since the 1980s, particularly in adolescents and adults, with the last major outbreaks occurring in 2004 and 2005.
Nationally, there were more than 7,000 cases of pertussis in 2007 and five deaths, according to the CDC. So far this year, fewer than 7,000 cases have been reported in the U.S., but there have already been 15 deaths, a 200 percent increase from 2007.
Public health officials are reminding residents to practice cough etiquette and frequent hand washing to limit the spread of infection.