A woman is holding a beautiful infant, swaddled in a thick blanket, a small purple bow affixed to her head. The baby looks up at her, all watery red eyes and foreboding, a cheek mashed into the thin tube that stretches across her face, through her nose and down the baby’s throat. Then the coughing starts. This baby is in the ICU with pertussis, and the footage of her desperate, gasping breaths and strangled, choking cough is heartbreaking. Less than 15 seconds into the video, the baby turns tomato red, her tiny lungs out of air, but still furiously coughing. The woman quietly soothes the baby and implores her to breathe, but the baby starts to writhe, fists balled up and pleading, silent and purpled. The baby furrows her brow and sways her head, starving for air, unable to breathe. The woman, holding that little bundle close, is ever so sweetly asking the baby to take a breath. And the baby isn’t breathing; in fact, it looks like she’s choking.

And then the breath happens.

It’s the most strained, urgent, sucking, gasping sound I think a being of that size could make, which is to say it is something immediate and terrifying enough to make your insides go cold. Hearing that baby breathe after struggling so hard should feel like seeing your lover’s ship sail into the bay, but instead that moment of joy is tainted by that sick feeling when you just know something is very, very wrong.

This disease is a baby killer; one or two out of a hundred will die.

Unlike many of the vaccine-preventable diseases — polio, HPV, and yes, measles — whooping cough is caused not by a virus, but rather a bacterium, Bordetella pertussis. Whooping cough itself is a respiratory infection, named for the awful sound that lungs make when they are struggling desperately to suck in air following a coughing fit. Before the development of vaccines, whooping cough was a leading killer of children. And pertussis is not to be outdone in our revival of the sickest: In fact, it’s been working on a comeback since the 1980s.

In the pre-vaccine era, whooping cough was a major player in infant mortality, with the U.S. seeing an average of 165,000 cases a year in the 1930s and 1940s. After the first pertussis vaccine became available in 1948, things dropped dramatically: We hit an all-time low of 1,010 cases in 1976, but the disease has been creeping back ever since. And it’s not just the antivaccine movement that’s boosting the numbers.

There are a couple of things that make whooping cough more complicated than, say, measles. Whereas catching measles in the wild gives you lifetime immunity, those who catch whooping cough can see protection drop off in as little as seven years. The same is true of vaccines: One doctor in Marin County, California, discovered that the majority of his whooping cough cases were aged 8 to 12 — and had been vaccinated. And because it can be carried without the carrier realizing it, this means it’s often the mother or a relative who exposes the infant to the bacteria.

The previous whooping cough vaccine was developed in the 1930s. It worked well, but it was a whole-cell vaccine — effectively injecting dead pertussis bacteria into patients — which had a high rate of side effects such as redness and swelling. So an alternative was developed, one that uses only part of the bacteria, but just enough to put the immune system through its training exercises. But the newer, safer vaccine has only an 80 to 90 percent success rate, making it less successful than its predecessor.

This is not to diminish the importance of this vaccine. Sure, it may not work as well as it could, but that doesn’t mean we should abandon it: The World Health Organization estimates that in 2008 global vaccination efforts against pertussis saved 687,000 lives. In less positive news, the U.S. pertussis rate in 2012 was its highest since 1956, with 48,277 cases.

No other creature — that we know of — gets pertussis. Like measles, it’s an exclusively human disease. It’s also a highly contagious one: Expose a susceptible individual, and there is an 80 to 90 percent chance that he’ll develop the infection himself.

It spreads because the human body does a great job turning the wet flesh of our lungs into a proficient and economical aerosolizer, launching a mist of infectious spittle with just a few rather forceful abdominal contractions. When a bystander breathes in this cloud of particulate pertussis, the hitchhiking bacteria dive right into the ciliated cells of his windpipe. These cells are the little guys on the surface who, upon closer inspection, appear to be quite hairy. They use their sticky tendrils to snag intruders, which works out just fine for B. pertussis.

Once inside the body, the bacteria happily multiply on the respiratory epithelium, a tract of pink and sticky skin that starts up in the nose and throat area and creates a lush home for our invasive bacterial lawn all the way down into the tender air sacs of the lungs.

In the early days of a whooping cough infection, it really does kind of just look like a cold: nasal congestion, drippy snots, runny eyes, and a low-grade fever. This soon gives way to the next stage, the cough, characterized by coughing fits so bad that lungs audibly scream for oxygen once the spasming passes. Patients cough so hard that they vomit, cough so hard their lips turn blue. They cough so hard they break their own ribs, give themselves a seizure or even brain damage.

The reason for this horrible hacking comes down to what whooping cough does to those little hairs. By damaging the cilia, B. pertussis takes away your body’s mechanism to clear its airways of mucus and crap in the air and infectious invaders. Without the cilia, thick goo collects in the delicate respiratory tract; this mucus-pus-blood cocktail, called mucopurulent-sanguineous exudate, creates desperate coughing fits as the body tries to clear its airway.

The third and final stage of pertussis — assuming no complications — is a cough that can last for weeks. But what if there are complications? One in five people with whooping cough had to be hospitalized because of their illness, and one of the most serious complications is pneumonia; it occurs in about one in 20 patients, but over one in 10 infants under six months. Other complications include neurological problems such as seizures (likely due to not meeting the brain’s oxygen demands), ear infections, and rib injuries.

It’s a lot like the flu: Healthy people can spread the virus without showing symptoms, the vaccine provides some degree of incomplete coverage, and those at risk are the immunocompromised — infants who are not old enough to have completed the vaccine schedule, infants born to those those who decline vaccinations, and the already ill. Combined with the shortened window of efficiency, what are public health institutions to do? As a representative from the Centers for Disease Control and Prevention told me, “Our current vaccination efforts are focused on… providing the best protection to those who are most at risk of catching and dying from whooping cough — babies — by vaccinating pregnant women.”

So yes, when a person says “eh” to whooping cough vaccines, all I can hear is “I’m okay with dead babies.” And while I have no doubt that there are those of you out there who are sociopathic enough to be unmoved by an unused baby shoes ad on Craigslist, it seems that for many there is a gulf between theoretical and applied empathy.

It’s easier to get people to care than it is to get them to act.

“A prevalent misconception is that herd immunity will product us,” explained the CDC. “It does not appear that we can gain herd (population) immunity from the currently available whooping cough vaccines, which although very effective, do not provide long-lasting protection. But even with that in mind, our current pertussis vaccines continue to be the best way to protect ourselves from whooping cough and its complications.”

Vaccines are not magic-bullet cure-alls. They exist to prevent disease, not establish a utopia where the only kids who get sick are other people’s. Like hand washing and covering your mouth when you sneeze, vaccinations are something we do for the health of ourselves, the health of our families, and the greater good of our communities. Are they perfect? No. Some are better than others. But the alternative is not good.

So if you’re pregnant, get vaccinated. If you have little ones, protect them. And if you’re coughing and you’re not sure if its just a cold or something worse, then, for fuck’s sake, stay away from babies.

A portion of the research for this series was crowdfunded on Inkshares.

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