Investigators hope new vaccine will help 'whoop' adult pertussis
Vanderbilt University Medical Center is one of eight institutions across the country studying a vaccine for adult pertussis to see whether it prevents the disease, commonly known as whooping cough or the "100-day cough."
About 250 adults between the ages of 15 and 65 are being enrolled in the portion of the study conducted at VUMC. About 2,000 participants are being enrolled nationwide. The participants are randomly assigned to receive either the pertussis vaccine or a control vaccine. Neither the participant nor the research nurse or physicians will know which is received until the study is completed.
The vaccine has already been proven safe and effective in previous VUMC vaccine trials.
Vanderbilt University Medical Center has been heavily involved in research on pertussis, an infectious disease most commonly found in children. The disease also occurs in adults who were immunized as children.
Studies by Dr. Seth W. Wright, associate professor of Emergency Medicine, have shown that approximately 21 percent of adults who come to the Vanderbilt Emergency Room with a cough that has persisted for more than two weeks have pertussis. In another study conducted in California, the incidence of pertussis was found to be about the same as peptic ulcer disease in adults, said Dr. Kathryn M. Edwards, professor of Pediatrics.
"These adults were all immunized as children, which suggests to us that immunity wanes," she said. Even the new vaccines wane in effectiveness, showing that there may be the need for adults to have booster vaccinations.
Adults with pertussis usually don't have a fever. A persistent cough is the major symptom. The disease is characterized by violent bouts of coughing that persist until the breath is exhausted and respiration becomes noisy, producing a "whoop" sound.
Once the cough begins, it won't respond to any treatment. It must be left alone to run its course, which may take as long as 100 days, Edwards said.
"If you're exposed to someone with pertussis, you can be treated with antibiotics and people with pertussis may be treated with antibiotics to prevent them from spreading the disease to other people."
VUMC is also participating in an additional aspect of the study, working closely with Dr. Claudius Meyer, a German scientist who is studying the cellular response in those who have been immunized with the pertussis vaccine and those who haven't. Research assistants in the lab have been taught how to preserve cells from cultures that are taken from participants in the vaccine trial. They freeze the samples and send them to Germany for further study.
Those participating in the VUMC portion of the vaccine trial will have blood drawn when they enroll in the trial and again at the end of one year when the study is completed. In addition, if the participants have a coughing-type illness during the year of study, they are asked to return for a culture to see whether the illness is whooping cough.
"The culture will show us whether those people who were given the pertussis vaccine have pertussis less than those who had the control vaccine," Edwards said. "It's a very close follow-up period, so we're hoping that many of our participants will be from the Vanderbilt community so if they have symptoms, we can culture them."
Participants in the study must be healthy, with no underlying lung problems. They will not be accepted into the trial if they have participated in another adult pertussis vaccine trial over the past five years.
Each participant will receive financial compensation for their efforts. For more information, call Jackie Harris, R.N., at 343-3461.