Bordetella bronchiseptca affects at least 10 states

Revere, Mass. — The disease killing greyhounds and closing racetracks in at least 10 states likely is a virulent kennel cough similar to the Bordetella bronchiseptica outbreak in 1999.

"Every five or six years we have one of these very large outbreaks," says Brad Fenwick, veterinary professor and vice president for research at Virginia Polytechnic Institute and State University. "The dogs will cough, but they are not running a fever and they are interested in running and all those things. But in a small percentage of them, they will develop a secondary bacterial pneumonia, which is classic out of the textbooks, and if you treat it properly, you won't have any mortality at all, but if you don't, then about a half percent will die from the disease."

The current pandemic has a 60-80 percent morbidity rate, Fenwick says.

At least 16 dogs died at Wonderland Park in Massachusetts, six more in Lincoln Park in Rhode Island and outbreaks were reported in Texas, Kansas, Florida, Iowa, Wisconsin, Nebraska, Colorado, West Virginia and Arkansas. Fenwick consulted with many of the tracks where outbreaks occurred, and the relatively high mortality rate in New England likely was due to failure to diagnose and prevent secondary illnesses, he says.

The Wonderland Park animals succumbed to beta-hemolytic Streptococcus, according to Kent Lage, Assistant Commissioner and Chief of Staff for the Massachusetts Department of Agriculture. They were treated with antibiotics, fluids and fever reducers. Wonderland was schedule to re-open June 10.

"The veterinarians who were seeing this animals (at Wonderland) had not experienced this before, and the people who were working the dogs weren't looking at them frequently enough," Fenwick says. "When you put those two things together, we had an exceptionally high degree of mortalities at that track. Other tracks have gone through the exact same thing — kennel cough outbreaks — all over the country, with very few or no mortalities at all."

Nearby Lincoln Park re-opened June 3 after closing for about a month. The Rhode Island dogs likely died of secondary pneumonia, but blood tests were not available at presstime.

The key to preventing mortality is recognizing that a classic kennel cough due to Bordetella, and then treat them and watch them a little closer than usual, Fenwick says.

"In a classic case of kennel cough where the dogs are coughing but are not particularly sick, our recommended treatment is doxycycline and some sort of penicillin or penicillin analog," Fenwick says. "That covers two sides of the equation: a secondary gram-negative infection and a secondary gram-positive infection. It turns out that the antibiotics really don't change the course of the coughing very much. They will still cough for seven to 14 days."

Fenwick's lab is collaborating with a private vaccine manufacturer to update the country's kennel cough vaccine. The manufacturer asked to remain anonymous, but there is no secrecy surrounding the hope of the collaboration.

"The intent is to have a kennel cough vaccine that is caused by Bordetella that is as good as the whooping cough vaccine we use for humans because the organisms are fairly identical and the diseases are fairly identical," Fenwick says.