Without vaccine mandates, infants could be in for invasive tests.

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My daughter recently called to tell me her otherwise healthy 7-month-old son, Sid—my first grandson—had a fever of 105. His normally peaches-and-cream complexion was gray, and his hair (to the extent that he has it) was matted down with sweat. My daughter and I are both pediatricians, so of course Sid is vaccinated. We felt comfortable assuming it was “just a virus” and would resolve uneventfully with Tylenol and fluids.

But with decreasing vaccination rates, resistance to vaccines on the rise, and a Health and Human Services confirmation hearing for an apparent anti-vaxxer occurring on Jan. 29, I wonder how many parents and grandparents will continue to have that assurance.

I have worked in pediatric emergency departments for the past 35 years—since before the innovative conjugate vaccines against streptococcal pneumoniae and Haemophilus influenza type B were licensed in the ’80s and ’90s and introduced into the early-childhood vaccine schedule. Before these vaccines, the incidence of bacterial disease—bacteremia, meningitis, and death—was high. We had to depend on evidence-based testing parameters (blood, urine, and spinal fluid) to determine a sick child’s risk for developing life-threatening disease. Otherwise, we couldn’t tell whose illness was something benign and viral, and would resolve uneventfully, and whose was bacterial and might end very differently. With these vaccinations, the risk to young children of developing a dangerous illness was so dramatically reduced that extensive testing was no longer needed. And for those who could not be vaccinated—because they were too young, had a preexisting condition preventing vaccination, or couldn’t mount an immune response—they were protected by herd immunity.

If Robert F. Kennedy Jr. is confirmed, and if vaccine mandates are removed, and parents are given permission to opt out for their children, vaccine rates could drop to 50 percent, if the number of people who get the influenza vaccine is any guide. When sick, Sid, or any infant, will likely not be able to sit at home, sweating it out.

This is how it was when I first started my career; I remember it vividly, and don’t want to see it again.

Sid would be in the emergency department, dressed in a gown. Screaming, he would be held down by medical staff, one at each flailing appendage and a fifth faceplanted across his torso. A tourniquet would be tied around his arm or leg and the search for a vein would begin. Most in a young child are invisible (unlike adult veins that protrude like overflowing estuaries), but are occasionally palpable beneath the skin as linear squishy balloons. A tiny needle would be inserted blindly into the spot above that squishy place—that hopefully had not rolled away by then—and with any luck, a stream of garnet-colored liquid would emerge. With Sid still squirming, the blood would traverse the attached tubing, landing in the syringe at the end. Unintended needle sticks were always a possibility, made worse since none of us wore gloves.

The next procedure would be urine collection. The area below the belly button and above the pubic bone would be swabbed with a cold, brown, sterile cleaning solution, and a 2-to-3-inch-long needle inserted perpendicular to the skin directly into the abdomen, aimed at the bladder. The plunger of the syringe attached to the needle would be pulled back and, hopefully, urine quickly accumulated. If not, the procedure would be repeated in a different area. Or, with concern that he could be dehydrated, an intravenous catheter would be inserted in whatever vein could be found and IV fluids dripped in for a period of time, at which point the procedure would be attempted again.

Alternatively, a plastic catheter, with a diameter equal to the size of a strand of spaghetti, would be inserted into and threaded up his tiny, wildly moving urethra while he was held sprawled on the stretcher like an outstretched frog, continuing to scream.

At this point he may have progressed to a breath-holding spell, as prolonged screaming often does in infancy, with blue lips and no air movement. The sterile procedure would need to be temporarily halted while a nasal cannula with nasal prongs was placed in both nostrils and the delivery of oxygen was begun. At this point, the urine extraction procedure would be restarted from the beginning with the cold, brown, sterile cleaning solution.

If he looked ill enough, a spinal tap would be performed, during which he would be curled into a ball like a fetus. A 1 ½–inch needle would be inserted perpendicularly into his back, carefully navigating between his small vertebrae, and then delicately plunged into the spinal cord—with a diameter the size of a piece of bucatini pasta—without going even a millimeter too far. (If it went too far, the needle would exit the far side of the space around the cord, causing fluid to leak out. In older patients, this would cause what is known as a post–lumbar puncture headache. In infants, what we know for sure is that it would necessitate the recommencement of the procedure.)

Sid would then receive an antibiotic injection to protect him against the possibility of bacteria in the blood, as it would take 24 to 48 hours to really know for sure what he was up against. For kids who are lucky, it really will be “just a virus.” But it could end up being much scarier—and even fatal.

This ordeal at the emergency department would not be an infrequent occurrence; fever in young children is common, affecting millions of infants and young toddlers annually. Young, vaccinated children like Sid are protected against many of the diseases that killed our ancestors: pneumococcal pneumonia, Haemophilus influenzae type-B meningitis, pertussis whooping cough, tetanus, diphtheria, and hepatitis B, as well as rotavirus, influenza virus, and SARS-CoV-2. And children older than him are also shielded from the fatal lung and brain disease caused by measles; the deafness, encephalitis, and testicular atrophy caused by mumps; and the birth defects and stillbirths caused by rubella in pregnant women.

But this will change if vaccine mandates are lifted. “It is likely these diseases will return,” remarks Peter Dayan, who is a pediatric emergency department attending at a major children’s hospital and a colleague of mine. “This will mean medicine will step back in time and revert to subjecting young children to painful procedures that we had been able to nearly eliminate for the last decades.”

To be clear, this could affect even children who are vaccinated, since without herd immunity, there will be more circulating disease, and the risk of disease will be higher. From the trenches of the emergency department or urgent care, the waters will be muddied. Inconsistent vaccination in children could lead to cumbersome and worrisome testing for more people.

There are other issues at stake. Increased testing and medical visits will lead to shortages of blood culture bottles, IV fluids, and nurses, as well as antibiotic overuse, leading to increases in drug-resistant bacteria. And, because of health inequity, these challenges will be worse for babies of color or in poverty. Moreover, 80 percent of children are not seen in designated children’s hospitals with practitioners who are trained to perform procedures on children, which could add to the trauma sustained by our kids.

Sid has thankfully recovered from whatever virus caused his high fever—without an emergency department visit, testing, or antibiotics. Vaccinations shielded him from serious bacterial illness and from the painful, traumatic workup that many children may be subjected to if vaccine mandates are dropped. And in that case, physicians—and grandmothers—will lose the luxury of saying “It’s just a virus.”

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