Personal Injury Law

Study - Pertussis Risk Higher For Unvaccinated Children

By Chrissie Cole

Children of parents who refuse pertussis (per-TUS-iss) immunizations are at a greater risk for developing the disease compared to vaccinated children, finds a new study published in the journal Pediatrics.

Pertussis - also known as whooping cough – is a highly contagious respiratory tract infection that affects more than 5,000 children a year, according to the U.S. Centers for Disease Control and Prevention (CDC).

While the onset of the disease resembles an ordinary cold, in rare cases whooping cough can become more serious in children and adults, especially infants.

The study, by Kaiser Permanente Colorado's Institute for Health Research, was the first to use medical records to confirm which children received immunizations and which ones did not – and the subsequent rates of whooping cough, said researchers.

The number of parents who refuse to immunize their children is small, but researchers say that number has been steadily increasing and may be contributing to the rise in preventable diseases in children.

Immunization has been credited with the eradication or control of diphtheria, measles, rubella, small pox, mumps and polio.

But with 10,000 U.S. cases of whooping cough in 2007, the illness is still entrenched.

'The U.S. immunization program has successfully eliminated many diseases that we no longer see. So it's essentially become of a victim of its own success,' said study author Dr. Jason M. Glanz, PhD, in a telephone interview with Reuters.

'Parents are now more worried about vaccine safety than about preventing the diseases themselves,' he said.

Glanz also said, parents wrongly rely on 'herd immunity' that assumes other parents will vaccinate their children so they don't have too, but the risk of an outbreak increases as more refuse to immunize.

For the study, researchers reviewed records of children 2 months to 18 years enrolled in the Kaiser Permanente Colorado health plan from 1996 to 2007. There were 156 lab-confirmed cases of whooping cough reported during the study period. Researchers compared these children to 595 children who didn't get whooping cough.

Children of parents who refused vaccines were 23 times more likely than vaccinated children to get the disease.

In a secondary analysis which was limited to children who were continuously enrolled at Kaiser Permanente from 2 to 20 months of age (the period during which the initial immunization series would be completed), there was a similarly high risk.

The researchers determined that 11 percent of whooping cough cases in the overall population were linked to vaccine refusal.

The CDC says the best way to prevent pertussis is through vaccinations. The childhood vaccine is called DTap. The whooping cough booster vaccine for adolescents and adults is called Tdap. Both protect against whooping cough, tetanus, and diphtheria.

The authors acknowledged that the study was limited by the use of data from a single health plan in one state. #

Full post as published by InjuryBoard on May 27, 2009 (boomark / email).