MADISON, Wis. -- There are several new immunization requirements for school children this year.

Madison Metropolitan School District students in grades 6 through 12 need a tetanus, pertussis and diphtheria vaccination, known as a Tdap booster, this year to protect against whooping cough, the district said.

Whooping cough is becoming a serious problem in some parts of the country. Six babies have died in California, WISC-TV reported.

So far, 14 cases have been reported in Dane County.

Local hospitals are now fighting the disease with a new concept called cocooning, WISC-TV reported.

"Cocooning is when you try to get everyone around the patient protected. So even if you can't get the patient protected, you can prevent the people around that patient from giving them the disease," said Dr. Thomas Murwin, a Dean Clinic pediatrician.

Murwin said he has seen firsthand the dangers of whooping cough. It's a serious bacterial infection that causes severe coughing spasms.

"It can be fatal for some kids. California's having a huge outbreak right now of pertussis, and the problem is trying to immunize infants. Even if you get their vaccines correctly at two months, four months and six months, the vaccine doesn't do as well as some other vaccines in protecting young kids," Murwin said.

Murwin said that in the case of whooping cough, infants are in very real danger.

"In smaller kids, their airway gets harder hit because it's much smaller in diameter and they have a hard time breathing and taking air in, and they get a classic whoop when they cough," Murwin said.

He said whooping cough is highly contagious and the coughing spells can last up to eight weeks.

"In an infant, you want to make sure that the mom has had pertussis (vaccine), the dad has had the pertussis vaccine. You also want to make sure that any caregivers have had the vaccine, like grandmas and grandpas and aunts and uncles," Murwin said.

St. Mary's Hospital nurse Kayla Anderson is cocooning to prepare for the birth of her second child in December.

"I guess I always ask the question, 'Why not?' Do the risks outweigh the benefits or do the benefits outweigh the risks? The chances of something happening are much greater than the risks and the side effects of the vaccine," Anderson said.

Murwin said the pertussis vaccine has been around for a decade and is safe. He said it's a much bigger risk to go without one.

"You may survive pertussis just fine, but you will feel very guilty if you realize that you passed pertussis on to somebody that you didn't want to pass pertussis on to," Murwin said.

Some parents choose not to vaccinate their children. Waivers are available to parents for health, religious or personal conviction reasons.

In the event of an outbreak of any vaccine-preventable disease, such as whooping cough, students who are no immunized may be excluded from school, WISC-TV reported.

Parents are urged to have their children immunized before school starts, but they have until Oct. 27 to get their shots up to date.