"We're asking parents to bring in vaccination proof now," said Pleasanton School District Nurse Susan Han. "Probably 40 percent of the students have had the booster, they just have not provided proof to their schools."
The law could have a huge impact on school attendance if families do not know about the law, Han said.
"I just hope parents take action now. The kids will be excluded from the first day of school if they don't have proof," she explained.
Children entering kindergarten already must show proof of a pertussis vaccination, which would protect them until age 10. After their 10th birthday, children should receive a Tdab booster to protect them against Pertussis (whooping cough) disease.
"What they found out was that the immunization does not provide lifelong protection like we used to think," said Han.
Pertussis is a contagious disease of the lungs and respiratory system, caused by bacteria. Infants and young children are the most vulnerable, as well as pregnant women, infant caregivers and household members.
"As of Nov. 26, 2010, Alameda County had reported 342 cases of pertussis and 0 deaths. Across California there have been 7,297 cases of pertussis and 10 deaths, all infants," according to the Alameda County Public Health Department website. "California has the most pertussis cases reported in 63 years."
"Whooping cough for adults or older kids usually starts off like a common cold. Then it gets worse and worse over one to two weeks," said Han. "You normally don't have fever. You have a coughing spell and then make a loud whooping sound, like you're trying to gasp. You may vomit as well."
It can last for weeks or months, she added, interfering with sleep.
But the biggest danger is spreading it to infants or young children, for whom it is life-threatening.
Call individual schools with questions or visit www.acphd.org/pertussis.