California is experiencing a concerning resurgence of whooping cough, a highly contagious respiratory disease also known as pertussis. This year alone, there have been 1,744 reported cases across the state, a dramatic increase from fewer than 300 cases last year. According to the California Department of Public Health, the surge in cases marks the highest level seen since before the COVID-19 pandemic, when transmission of many common respiratory illnesses had significantly declined.
Infants, particularly those under one year old, face the highest risk from whooping cough. The U.S. Centers for Disease Control and Prevention (CDC) also notes that people with compromised immune systems or those with moderate to severe asthma are vulnerable to severe symptoms. Los Angeles County, in particular, has seen a spike, with 347 confirmed and probable cases so far this year. This figure has nearly tripled since last year and is four times higher than in 2022.
Nationwide, the trend follows a similar pattern, with more cases of whooping cough reported this year compared to 2019, the last pre-pandemic year. Many experts attribute the increase to a mix of decreased immunity and relaxed COVID-related precautions that had previously limited the spread of respiratory infections. In Los Angeles County, the number of cases this year is already 3.5 times higher than at the same point last year.
Health officials are keeping a close eye on the situation, especially in schools. Dr. Nava Yeganeh, medical director for Vaccine Preventable Disease Control at the L.A. County Department of Public Health, notes that reports of whooping cough infections in schools have become more common. Efforts are underway to curb the rise in cases and protect vulnerable populations.
Whooping cough tends to peak every three to five years, and experts believe the current surge is overdue. The last significant increase in California occurred in 2019, and while the numbers haven’t yet reached that year’s level, the trend is concerning. In 2019, Los Angeles County alone reported 1,691 confirmed, probable, and suspected cases of whooping cough.
California has faced severe whooping cough outbreaks in the past. In 2010, the state recorded over 9,000 cases, marking the worst year in decades, and ten infants died from the disease. Four years later, another surge saw over 11,000 cases and two infant deaths. The last infant death in Los Angeles County due to whooping cough occurred in 2014.
The illness, which starts with cold-like symptoms, can quickly escalate into severe, persistent coughing fits that last for weeks or even months. The cough, which contains contagious bacteria, can easily spread to others nearby. People with whooping cough are contagious as soon as they feel ill and remain so for at least two weeks after symptoms start. Antibiotics can help reduce the infectious period and limit transmission.
The disease gets its name from the characteristic “whooping” sound made when a patient gasps for air after a coughing fit. Many describe the bouts as some of the most intense and exhausting coughing they’ve ever experienced. Those who exhibit symptoms are encouraged to get tested, seek treatment, and stay home to avoid spreading the illness.
For infants, whooping cough can be particularly severe, sometimes causing apnea, a condition where breathing pauses for a dangerous length of time. In these cases, babies may turn blue as they struggle to breathe. The disease can also lead to pulmonary hypertension, a condition in which blood flow to the lungs is obstructed, resulting in life-threatening complications. The pertussis toxin can trigger a rise in white blood cell count, causing blockages in the arteries that supply the lungs.
School-age children are not immune from severe illness, either. In some cases, the cough is so intense that it disrupts sleep. Adults, too, can experience severe symptoms, with some coughing so violently that they fracture ribs.
Vaccination remains the most effective way to prevent whooping cough. Babies can receive the DTaP vaccine starting at two months old, which provides protection not only against pertussis but also against diphtheria and tetanus. A different formulation, the Tdap vaccine, is given to adolescents and adults, with booster shots recommended every ten years. Since 2012, health officials have also advised pregnant women to get vaccinated during every pregnancy. This ensures that protective antibodies are passed from mother to baby.
It’s crucial for anyone who cares for infants to be vaccinated against whooping cough, as the disease can be devastating for the youngest and most vulnerable. Although the vaccine does not completely eliminate the risk of infection, vaccinated individuals who contract whooping cough tend to experience milder symptoms.
For those exposed to whooping cough but not yet sick, antibiotics can provide a layer of protection. The CDC recommends post-exposure prophylaxis for all household contacts of an infected person within 21 days of the onset of coughing. This step is essential, as roughly 80% of household members are likely to catch the illness if exposed.
Data analysis shows that the San Francisco Bay Area currently has the highest per capita rate of whooping cough in California, with 17 cases per 100,000 residents, exceeding the statewide average of five cases per 100,000. Marin County, in particular, stands out with 129 cases per 100,000 residents, a figure that can partly be attributed to robust testing and early detection practices.
San Diego County follows closely, with 14 cases per 100,000 residents. So far, the county has recorded 547 confirmed and probable cases this year, a rise from 332 in 2023. Local officials report that patients have ranged in age from under one month to 85 years old, with a significant concentration of cases among adolescents aged 11 to 17.
According to Dr. Ankita Kadakia, interim San Diego County public health officer, the number of whooping cough cases is on track to reach pre-pandemic levels, indicating a sustained upward trend. In Orange County, 74 cases have been reported so far this year, up from just 11 in 2023. Although this is still below the 185 cases documented in 2019, the increase has prompted local health officials to reinforce preventive measures.
Southern California, including Los Angeles and Orange counties, has reported lower rates compared to the Bay Area, with an average of about two cases per 100,000 residents. This disparity highlights regional differences in testing, reporting, and possibly vaccination rates.
Prevention remains a key focus for health officials as they navigate the complexities of whooping cough’s resurgence. Enhanced public awareness, timely vaccinations, and vigilant monitoring of symptoms are essential steps to protect communities, especially the most vulnerable members like infants and those with weakened immune systems.
As California continues to deal with this rise in whooping cough cases, the need for community-wide vigilance and effective preventive measures is clearer than ever. The trends in local counties offer valuable insights into how the disease spreads and underscores the importance of both individual responsibility and public health interventions to curb its impact.