Parents advised of 11 recent cases of whooping cough at La Cañada High

In a letter sent to La Cañada High School parents last month, school officials announced a case of whooping cough was discovered and warned to take precautions: educate yourself and cover your mouth.

Now, the district nurse says, they’re aware of 11 cases.

That nurse, Chris Henry, said via an email the first case was discovered in early November, leading officials to send the letter to staff and parents just before the Thanksgiving break. Also in an email, Interim Principal Jim Cartnal clarified that the letter Henry sent out, from the L.A. County Public Health Department, addresses how families can get treatment.

Janesri De Silva, the medical director at Kids and Teens Medical Group in La Cañada, said she hasn’t seen in her office any recent cases of whooping cough, also known as pertussis, which may be owed to the fact that her colleagues “always try to immunize and protect our kids.”

While adolescents typically recover from whooping cough, De Silva said, infants are at a greater risk due to undeveloped immune systems. An infant in San Bernardino County died this summer after contracting the disease.

Around the time of that death, officials warned that California could see an outbreak this year, according to the Los Angeles Times. Outbreaks are predicted to occur every three to five years and the most recent were in 2010 and 2014.

In the latest outbreak four years ago, 1,231 confirmed cases of whooping cough were reported in L.A. County, said Michelle Parra, the director of the vaccine preventable disease control program at the L.A. County Department of Public Health.

In comparison, there have been 237 confirmed cases in the county this year as of the end of October, Parra said.

The student newspaper at Harvard-Westlake School in Los Angeles reported this week that eight students were diagnosed with pertussis. There, the school notified only the parents of students who share classes or activities with those affected, according to the Chronicle.

A recent outbreak also surfaced in Marin County in Northern California. The Mercury News reported an outbreak this year hit hardest in local high schools — one school had 56 cases in the spring — while a school district reported this month all three of its schools had students affected by the illness.

Pertussis is spread “easily through the air when a person who has whooping cough breathes, coughs or sneezes,” according to a county Public Health Department fact sheet.

The most effective way to prevent whooping cough is to get the vaccine, according to the Centers for Disease Control and Prevention. In La Cañada, Henry said, officials are advising that families take precautions such as education and support.

An online resource that tracks immunizations required for school entry shows the vaccination rate at LCHS 7/8 is within the safest range for herd immunity, at or above 95%.