Whooping cough cases at record pace

PHOTOGRAPHER: Bethany Bump

Local and national health officials are seeing more of the shrill, convulsive coughing fits brought on by whooping cough than they have in a long time.

In fact, the highly contagious bacterial disease known as pertussis is so prevalent that 2012 is on track to be the worst year for whooping cough in the United States since 1959. And New York is on track to exceed a 10-year peak in whooping cough cases reached in 2004.

If local health officials are worried about the startling rise in cases, they’re not letting on just yet.

“Pertussis is a disease that is cyclical in nature,” said Marci Natale, deputy director of the state Department of Health’s Public Affairs Group.

By definition, that means a surge in whooping cough is expected every three to five years. But the surges are nearing record highs.

In the Capital Region, county health departments are reporting a higher-than-normal prevalence of whooping cough that they haven’t seen in seven or eight years. Albany County has had 42 confirmed cases so far this year, the most in the Capital Region, with another possible case being investigated, said county spokeswoman Mary Rozak.

“So we’re talking about a rate that’s three times higher than last year,” she said. “But we are consistent with what’s going on throughout the rest of the state and across the country.”

In the past decade, the county has experienced annual totals ranging from one reported case to a high of 93 cases in 2004 — the same year the state Department of Health reported a whopping 2,165 cases.

High numbers don’t necessarily indicate an outbreak, though. Rensselaer County has experienced 26 cases so far this year, but with 11 occurring in just the past month, the Rensselaer County Health Department issued a statement Tuesday calling the surge an outbreak.

The state classifies a whooping cough outbreak as two or more cases that occur within 42 days of each other and in the same setting, said Natale.

“As in, the same school, workplace, social gathering, health care setting or other location in common with each other — not two people in the same county who are geographically separate from each other and have never met,” she said.

The high numbers in the rest of the Capital Region occurred in the latter fashion — as separate, isolated incidents. Saratoga County, for example, is reporting 37 isolated cases of whooping cough so far this year — another peak in the regional cycle.

“We had 85 cases back in 2004 or 2005,” said county Public Health Director Karen Levison. “But in 2009, we had only one. I think that the state and [federal Centers for Disease Control and Prevention] are still working on just what is causing the numbers, and are talking about waning vaccination rates or growing immunity. They don’t know if the protection is as good as it used to be.”

The CDC confirmed earlier this year that the nation is on track to exceed the 40,000 whooping cough cases reported in 1959, and the reason may stem from the effectiveness of the vaccine. Some experts say the newer, safer version of the vaccine that replaced the decades-long version given to children up until the 1990s may be to blame. Others attribute the surge to over-diagnosing and false positives that arise from over-testing.

Two of the three cases of whooping cough that recently cropped up in Schoharie County only occurred because the children hadn’t been vaccinated, said Schoharie County Public Health Director Asante Shipp-Hilts. The rural county has a small population, so the seven cases it’s seen so far this year are slightly alarming, she said.

“Seven is certainly higher than what we usually have, which is zero to one,” she added. “There’s no obvious reason as to why it’s higher this year versus others.”

The risk of contracting any disease is measured by its incidence rate, or the number of new cases that occur in relation to the population.

Capital Region incidence rates vary from 6.1 in Montgomery County — where three cases have been confirmed so far — to 18.6 in Schoharie County, based on cases reported to the state Department of Health as of Aug. 31.

Fulton County is another rural area with a high incidence rate, with 10 cases confirmed through Aug. 31. Public Health Director Denise Frederick did not return calls for comment Wednesday.

Parents in Schenectady County were on alert in May, when two cases were confirmed at Niskayuna High School and three more at area elementary schools. So far, the county has experienced 21 reported cases of whooping cough.

“The numbers are rising, but so are the numbers throughout the entire state,” said county spokesman Joe McQueen. “We need to get the message out to make sure people are aware of the disease, are looking for it and are getting vaccinated.”

Whooping cough is diagnosed when a person has a cough lasting at least two weeks that occurs in fits and whoops, and sometimes causes vomiting. Signs to watch for include cold-like symptoms, such as a runny nose, congestion, fever and mild cough. Children and infants are especially susceptible.