Apodaca: Here’s what keeps this Orange County doctor up at night

In 1796 scientist and physician Edward Jenner, building on the work of others, pioneered an effective method of immunization against smallpox, a terrible disease that killed an estimated 20% of those infected. Often referred to as the father of vaccines, he is credited with saving millions of lives.

By the early 20th century, vaccinations for other diseases had been developed, and by the late 1940s mass production of vaccines was possible, enabling widespread protection. One by one, diseases that had plagued humankind were vanquished. Without question, vaccines are one of the greatest — if not the greatest — achievement in medical history.

You would think that 220 years of rigorous scientific research, enough supporting studies to fill an Amazon warehouse, and generations of astonishingly successful real-world results would be enough to dispel any lingering doubts about the relative safety and efficacy of vaccines.

Yet here we are today, with vaccine hesitancy and denial growing across the nation, and anti-vaccine crusaders embedded in the halls of power. Outbreaks of measles, one of the most contagious viruses known, are popping up all over the country, and the number of cases in California so far this year has already surpassed the total for all of 2024.

It’s not just measles that we need to worry about, though. Because of its devastatingly effective person-to-person transmissibility, measles is just the proverbial canary in the coal mine — a sign of more bad stuff to come. If we continue down the path of declining vaccination rates — overall rates have softened and in some communities they are dismal — we are likely to see outbreaks of other old-timey diseases that we had once believed were consigned to a sicker, deadlier past.

I first spoke with Dr. Jasjit Singh about the measles outbreaks a few months ago. An expert in pediatric infectious diseases, she serves as assistant director for the division for Children’s Hospital of Orange County and the medical epidemiologist for CHOC Hospital. She has devoted her impressive professional career spanning decades to the study and prevention of infectious diseases.

I returned to Singh to discuss what we are in danger of seeing next.

“The important thing I want people to understand is, as vaccination rates drop, what you see first are the most contagious diseases,” she said. “Measles are a great example of that. But there are other diseases that are very contagious as well.”

Pertussis, commonly known as whooping cough, is a prime example.

A highly contagious respiratory tract infection that causes a persistent hacking cough and strained breathing, pertussis has been easily preventable for more than a century. A vaccine that protects against it was first developed in 1914, and in 1948 it was combined with diphtheria and tetanus vaccines to be given as the standard childhood DTP vaccine.

But numbers of pertussis cases have been climbing in recent years, and that is particularly dangerous for infants who haven’t yet received their full round of shots. Infected babies struggle to breathe and are at risk of choking on mucus. Some get pneumonia and must be put on ventilators. Oxygen levels drop and pulmonary hypertension can develop. A few infants have died from pertussis this year.

“It’s painful to watch,” Singh said.

One way to help protect infants is for pregnant women to receive the vaccine, enabling them to pass the antibodies to their babies. But those numbers are declining as well; as of April, only 55% of pregnant women had gotten the vaccine.

Singh also worries about chicken pox, another easily transmissible disease that can be prevented through vaccination. It’s not just the potential for a later-in-life shingles outbreak caused by the dormant chicken pox virus that concerns her.

“Once again, I think there’s a sense that chicken pox is not that big a deal,” she said.

For most people, chicken pox infections resolve without serious complications. But children and adults with compromised immune systems are vulnerable to severe side effects from the virus, including pneumonia, liver inflammation, and encephalitis. Infections of flesh-eating bacteria, even in otherwise healthy people, can occur. Singh has seen children with leukemia that have developed horrible, life-threatening complications as the virus spread to their organs.

“You just want to run out and get everyone vaccinated,” she said.

There are other diseases that could return — polio, for instance, the paralyzing virus that once terrorized the nation. It wouldn’t take much. Pockets where vaccination rates fall below the level at which transmission within a community stalls could become the nexus of an outbreak.

As of now, the outlook isn’t encouraging, as vaccine skepticism fueled by rabid misinformation continues its ascendence.

Last month, Health Secretary Robert F. Kennedy Jr., a longtime vaccine critic, fired everyone on the federal panel that provides recommendations on the childhood vaccination schedule, and replaced them with like-minded skeptics. The move sent a chill through the medical establishment nationwide, raising fears that people will shun vaccines in even greater numbers.

The growing likelihood of that possibility keeps experts like Singh awake at night.

“This is not where I thought I’d be in the latter years of my career,” she lamented.

Nor is it where any of us should be.