Better check the calendar because it's feeling a whole lot like 1959.

There have been more than 18,000 cases of whooping cough reported in the United States so far this year, and nine deaths. Winter, when respiratory illnesses hit hardest, is yet to come, so they will likely far surpass the record 40,000 cases back in '59.

Canada doesn't do nearly as good a job at data collection as the U.S., but we know anecdotally that there are significant outbreaks of whooping cough in British Columbia, Alberta, New Brunswick and Southwestern Ontario. At least one baby has died, one-month-old Harper Whitehead of Lethbridge, Alta.

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Pertussis – the formal name for whooping cough – is a bacterial infection. It's preventable. In fact, we've had a vaccine for 70 years, yet we're galloping blithely toward levels of disease not seen since the prevaccination era.

What is going on here? Has science failed us? Or have we failed to use the tools we have to protect children from sickness and death?

The ongoing whooping cough outbreaks occurring now in North America – and in parts of Europe, where rates have jumped 10-fold in the past year – are a striking example of the latter.

Well-meaning parents are shunning vaccination in small but significant numbers because of imaginary fears largely concocted by quacks and charlatans. In doing so, they are giving almost-forgotten diseases the ability to resurface and cause real harm.

The bacterium Bordetella pertussis is, for adults, largely a bother. It infects airways and causes a persistent, nagging cough, which is why the illness is sometimes called the 100-day cough.

Pertussis actually means "violent cough" and, in some cases, the coughing is so violent that people suffer broken ribs, hernias, vomiting or loss of consciousness.

In children, however, pertussis clogs up the airways even more thoroughly, causing kids to gasp for breath between coughs and producing the telltale "whoop, whoop" sounds that gives the disease its moniker.

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In some cases, it can lead to pneumonia, convulsions, brain damage and death. One in every 200 young children who is infected with pertussis dies; all of them suffer.

The younger the child, the greater the danger: About 90 per cent of pertussis deaths occur in babies under the age of one.

Whooping cough remains a major cause of death globally, killing more than 300,000 children each year.

But in Canada, like in all developed countries (and many developing ones), we vaccinate kids. They get pertussis vaccine, along with diphtheria and tetanus, a combo known as DTaP (we will explain the little "a" in a minute) at two, four, six and 18 months, and then again at ages 4-6 and 14-16.

Babies like Harper Whitehead are too young to be vaccinated. They depend on others to do so. Universal vaccination creates what is called herd immunity, making it difficult for bacteria like pertussis to circulate and infect the vulnerable, like babies, the frail elderly and those with weakened immune systems.

"We're hopeful that sharing our story will send a message to people who don't think the disease is real and choose not be immunized or have their children immunized. This is real," said Dani Whitehead, Harper's grieving aunt.

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These tragedies were all too real before vaccination was developed and embraced. It was so effective that the childhood whoop-whoop became a rarity; in Canada, pertussis rates fell from 200 per 100,000 people to below two per 100,000.

But we became complacent. In the early 1990s, rates began to creep up again. This was a direct result of fears about vaccination, which really took off as the popularity of the World Wide Web grew.

Much has been written about the MMR (measles, mumps, rubella) vaccine and claims that it causes autism – which are totally unfounded, by the way, and were perpetuated by a researcher trying to get rich off a new measles vaccine. But the DTaP vaccine was also a target, the victim of unscientific claims that it caused neurological damage.

The reality is that DTaP did have a lot of mild side effects, mostly redness and swelling at the injection site, and some fever. But it is pertussis infection, not vaccination, that can cause neurological damage and death.

Nevertheless, the vaccine was reformulated. Instead of using whole killed bacterium, only proteins from the surface were used. That made it an acellullar vaccine (hence the little "a.") The change almost eliminated the side effects but also seems to have lessened the potency of the vaccine. That means adolescents and adults now need booster shots. This is particularly important for anyone who is around young children, from parents through to daycare workers.

The combination of lesser effectiveness and reduced vaccination rates is fuelling the current outbreaks. But the real culprit is ignorance, this erroneous notion that vaccines are more dangerous than disease.

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Failing to get vaccinated is selfish – and it can be deadly.

Chelsea Charles, whose 27-day-old baby Kaliah Jeffery died of pertussis earlier this year, pleaded with people to roll up their sleeves. A little pain from a needle prick, she told USA Today, can save a lot of suffering.

Ms. Charles put it in these stark terms: "Would you rather have a baby die than be vaccinated?"

Editor's note: The DTP vaccine was made with whole killed bacteria; it was reformulated using only proteins from the surface of the bacteria.