Pertussis cases on the rise

Monday, January 24, 2011

A nationwide surge in cases of pertussis, also known as whooping cough, has local doctors and pharmacists pressing for broader immunization against the highly contagious, potentially deadly bacterial infection.

"When we read about those outbreaks in other states, we feel like it could happen here," said Margaret Zylstra, epidemiology manager for the Chattanooga-Hamilton County Health Department.

Hear the sound of whooping cough in a child

The number of cases in Tennessee is low but has risen in recent years, despite the availability of a booster vaccine since 2005.

The disease has reached epidemic levels in California -- more than 8,300 cases and 10 infant deaths in 2010, the most in 50 years, according to the U.S. Centers for Disease Control and Prevention.

States including Michigan, Ohio and South Carolina are also seeing outbreaks, and federal and state health officials are encouraging more vaccination.

LOCAL PERTUSSIS CASESTennessee* 2005 -- 214* 2006 -- 181* 2007 -- 76* 2008 -- 122* 2009 -- 206* 2010 -- 222Georgia* 2005 -- 79* 2006 -- 101* 2007 -- 37* 2008 -- 116* 2009 -- 230* 2010 -- 225Hamilton County* 2005 -- 15* 2006 -- 8* 2007 -- 1* 2008 -- 3* 2009 -- 11* 2010 -- 3Source: State, Hamilton County health departments

Though only a few cases were confirmed locally in the last year, recent high rates of respiratory illness have doctors thinking that whooping cough is behind at least some of those problems.

Typically spread by coughing or sneezing, the disease often goes undiagnosed in adults but can be fatal to infants, particularly those under 6 months old, experts say.

"Whooping cough is back big-time in adolescents and adults," said Dr. Richard Moody, a family medicine doctor in Chattanooga. He said he's been "aggressive" in encouraging patients to get booster shots, since immunity from vaccinations in infancy wears off by middle school.

This month, two Chattanooga Bi-Lo pharmacies started offering $50 pertussis booster vaccines, said Maggie Barrie, a pharmacist and immunization coordinator for Bi-Lo.

"We're doing a response to primarily OB-GYNs that are worried about it," she said.

To further protect newborns, "we're primarily trying to hit some of these dads that are 28, 29 years old and they don't have primary care physicians," she said.

Immunizing parents helps create a "cocoon of immunity" around the babies, experts say.

PREVENTING THE SPREAD

Pertussis tends to come in waves. In Tennessee, pertussis cases have risen steadily since 2007 and reached 222 last year, the highest number in at least six years.

In Georgia, there were 230 cases in 2009 -- nearly double the year prior -- and 225 cases in 2010. One Georgia infant died in 2009.

Infants get a series of pertussis immunizations beginning at 2 months old, but until the series is complete, they are vulnerable, health experts say.

"A young baby does not have the lung power to dislodge mucus in the bronchial tract," said CDC spokesman Jeff Dimond.

Babies can cough so hard, they break a rib or break blood vessels around their eyes, he said.

"It looks like they've been in a boxing match or something," Dimond said.

And pertussis is "incredibly contagious," said Kelly Moore, medical director of the immunization program at the Tennessee Department of Health.

"You have an 80 percent chance of coming down with pertussis if you live in the same house as someone who has it," she said.

In October the Advisory Committee on Immunization Practices -- a committee of experts selected by the U.S. Department of Health and Human Services -- called for expanded vaccinations against pertussis.

In Tennessee, seventh-graders must be vaccinated before enrolling in middle school.

Georgia health officials are conducting public education on the importance of vaccination for adolescents and adults, said Dr. Anil Mangla, director for infectious disease and immunization and acting state epidemiologist for the Georgia Department of Community Health.

Word of the new vaccination recommendations is spreading, Moody said.

"I've had a few people actually come in and tell me, 'I've got a grandbaby and I've been told I need it,'" he said.

ENDEMIC DISEASE

One of the "great mysteries" of pertussis is that it spikes every three to five years in the United States, Dimond said.

Nationally, about 20 infants die each year from pertussis, said local infectious disease specialist Dr. Mark Anderson.

"It's not very many, unless it's your infant. In a vaccine-preventable disease, we've sort of said that's unacceptable in our country," he said.

Some doctors worry about other contributors to the spread of the disease.

Unfounded fears about vaccines causing autism or harming the immune system have led more parents to forgo vaccination for themselves or their children. Doctors fear that is causing outbreaks of diseases that haven't been major problems in generations, including pertussis.

Dr. Nita Shumaker, president of the local medical society, said her Chattanooga pediatric office recently decided to stop taking children whose parents refuse to get them vaccinated.

"We're having to say, 'That's not in your child's best interest, and we're not going to support your decision,'" she said.

The success of a vaccine campaign in the 1940s to immunize against rampant pertussis in some ways works against vaccine advocates today, Shumaker said.

"If it's something [parents have] never seen and don't know anything about, then the shot becomes more of a risk than the disease," she said.


BY THE NUMBERS

Reported pertussis cases in the U.S. declined sharply with the widespread use of a vaccine in the 1940s.

* Peak in 1934 -- 265,269 cases

* Low in 1976 -- 1,010 cases

* Resurgence in 2004 -- 25,827 cases

Source: Centers for Disease Control and Prevention


SYMPTOMS OF WHOOPING COUGH

* Starts with coldlike symptoms and maybe a mild cough or fever.

* Severe coughing can begin after one to two weeks.

* Coughing fits can continue for weeks and can cause vomiting and exhaustion.

* In infants and children, there can be a distinctive "whooping" sound after a coughing fit as they try to catch their breath.

Source: Centers for Disease Control and Prevention, Chattanooga-Hamilton County Health Department


UPDATED IMMUNIZATION RECOMMENDATIONS

* Infants and children receive a vaccine series called DTaP that protects against diphtheria, tetanus and pertussis. Shots are given at 2, 4 and 6 months, between 15 and 18 months and when a child enters school.

* Adolescents ages 11-18 and adults ages 19-64 should receive a single dose of an adult booster called Tdap, since immunity fades over time.

* Children ages 7-10 who haven't been fully vaccinated against pertussis and adults over age 65 who anticipate contact with an infant should also get a Tdap booster shot.

* People don't have to wait five years after a tetanus or diphtheria vaccine to safely get the Tdap booster.

Source: Centers for Disease Control and Prevention