MAYVILLE, N.Y. - An outbreak of pertussis, which medical authorities believe may have started in a local hospital, has erupted in the upstate New York county of Chautauqua with nearly 100 confirmed cases. The outbreak is expected to continue spreading for about the next four months.
"We're still in the middle of this," Robert Burke, MD, Chautauqua County Health Commissioner, said of the outbreak of the upper respiratory infection that began in August. Burke has called it the largest outbreak of pertussis in the county.
By the third week of October, medical officials had identified 93 cases that met the case definition of a positive polymerase chain reaction (PCR) test and a 14-day cough. Burke said approximately 750 people have been tested.
Of the approximately 500 results that have come back, 166 non-cases were found. These people had a positive PCR but had a history of less than 14 days of coughing, said Burke. The remaining 250 people tested are termed pending cases because they have not been coughing for 14 days, yet.
Burke said an instructive aspect of the pending cases is that the majority of these cases were asymptomatic in that they had no history of coughing. With the assistance of officials from the Centers for Disease Control and Prevention, "we got information out to local physicians - look only at symptomatic individuals," said Burke.
There have been six hospitalizations, Burke said, noting that the outbreak has swept across a broad range of county residents, with the oldest a 90-year-old nursing home resident and the youngest a 1-month-old baby. All of those hospitalized are children younger than 6 months who have not yet been fully immunized against whooping cough with three doses of pertussis vaccine.
Burke said the overwhelming cases of the disease are young people who have had their three vaccinations as infants, but whose immunity to pertussis is now waning. Although fully immunized individuals in the age range of 8 to 10 years are being infected, it is a milder form of the disease than commonly associated with pertussis.
"We're just seeing people with bad coughs. That's what is interesting about the outbreak," said Burke. "This is very different from the traditional whooping cough that we've been trained to see. It's a subtle disease in many people, but you don't have a secondary illness like pneumonia."
The outbreak is similar to those that have occurred recently in Cincinnati and in nearby Buffalo-Niagara Falls, N.Y., two years ago, according to Burke.
The infection is being treated with erythromycin, which Burke termed "an awful drug" because it can cause diarrhea, vomiting and nausea, but is effective in containing the spread of the highly contagious disease. The drug is also being prescribed for those in close contact of confirmed cases.
While it may be some time before Burke and his colleagues will be able to get the time to map the cases and track down the initial outbreak, he suspects that it may originate with a teenager who was brought to a local hospital's emergency room. He said the patient was apparently misdiagnosed as having asthma. The teen returned to the hospital several times, still complaining of asthma-like symptoms, but it turned out to be whooping cough. The repeat visits resulted in a staff infection, said Burke.
Burke said that two local hospitals have "almost been wiped out" because of the number of staff who are now symptomatic. He said that in one maternity ward, three nurses appear to have whooping cough, while about five staff members of a single emergency room have contracted the disease.
"Every doctor in family practice is howling with the workload of telephone traffic" as a result of the outbreak, Burke said. "If this gets into your community, it can eat up your office."
The disease is jumping from family to family within a community, and then from town to town. It has affected the college communities of Dunkirk-Fredonia, where a state university campus of 35,000 is located, and then spread to smaller towns. It has radiated in every direction, he said. "We are dealing with a smoldering disease."
You can express your views on this article, or other relevant themes, in the Infectious Diseases in Children Specialty Forums.