A 6-year-old boy who died from rabies over the weekend could have been saved by a vaccine, doctors say.
Ryker Roque died after being scratched by a bat his father had put in a bucket after finding it.
The vaccine that could have saved him is one of the most effective vaccines there is, with 100 percent efficacy against a virus that is otherwise nearly 100 percent fatal, according to the Centers for Disease Control and Prevention.
But it’s also one of the most widely feared and misunderstood vaccines.
Here's what you need to know about the modern rabies shot:
They did used to be awful
The first rabies vaccine was developed more than 100 years ago and it was crude. “It was a nerve tissue vaccine, which means you infect an animal with rabies, take its brain, mash it up and make a vaccine out of that,” said Dr. Ryan Wallace, a rabies expert at the CDC’s National Center for Emerging and Zoonotic Infectious Diseases.
“There are a lot of really bad reactions that people and animals have to nerve tissue vaccines.” They included a temporary paralysis similar to Guillain Barre Syndrome, caused when the body’s immune system mistakenly attacks healthy nerve tissue.
And yes, it once took 13 doses of vaccine delivered into the stomach muscle, in part because the vaccine itself was high-volume, delivering a lot of liquid.
Rabies vaccines are better now
Modern rabies vaccines are grown in cells in lab dishes and are cleaner and more effective. “They have very low rates of adverse events and they are more potent so we only need a series of four shots, as opposed to the 13 shots you would get in the stomach in the old version of the vaccine,” Wallace said.
The four-dose regimen is 100 percent effective in preventing rabies, Wallace said.
People who fear they’ve been exposed to rabies first get an injection of immune globulin — premade antibodies designed to grab any circulating virus right away. Then they get four doses over 14 days of the preventive vaccine, which boosts the body’s own immune response.
“It’s the same volume and same pain level as the flu vaccine,” Wallace said.
It’s not a routine vaccine for people
Dogs and cats get regular rabies vaccines and most jurisdictions have strict laws for vaccinating these pets. But not so for people. The Advisory Committee on Immunization Practices details who should get rabies vaccines routinely and they include vets, spelunkers (people who explore caves) and lab workers.
“The vaccine is given based on need,” Wallace said.
People traveling to areas with a lot of rabies, such as India or Peru, can ask for rabies vaccines as a precaution. And the vaccine is given to anyone who may have been exposed to rabies: such as people bitten by a known rabid animal; those bitten or scratched by an animal that potentially could be rabid; and those otherwise exposed to rabies by bites or saliva.
“Between 40,000 and 60,000 people a year get the rabies vaccine — almost everyone who should,” Wallace said. “It is widely available. It’s one of the reasons we have so few human deaths from rabies in the United States.”
There is time to get one, but not too much time
People usually have time to get vaccinated after they believe they’ve been exposed to rabies.
“With rabies, the incubation period is extremely variable — three weeks to three months,” Wallace said.
Once people start showing symptoms, it’s almost always too late to vaccinate. A treatment called the Milwaukee protocol has saved 18 people out of 80 people who have tried it, says its inventor, Dr. Rodney Willoughby of Children's Hospital of Wisconsin.
Any animal bite should be cleaned right away. “Washing the wound can reduce the risk of death by 40 percent,” Wallace said. And then people need to go see a doctor immediately.
“If you’ve been previously vaccinated … any future exposures require a two-dose booster series. Under that protocol we haven’t had any vaccine failures,” Wallace added.
There is still a lot of rabies around
Rabies still kills 55,000 or more people a year around the world, the World Health Organization says. There are only a handful of cases in the U.S. thanks to vaccination. Strict laws of immunizing dogs has eliminated the dog strain of rabies in the U.S. although other strains exist in bats, raccoons, cats and other species — and dogs can catch those strains.
“Cats are the No. 1 rabid animal among domestic species, more than dogs, more than cattle, more than horses,” Wallace said.
Any mammal can catch rabies, but bats are the main reservoir in the U.S. that’s dangerous, since bats have tiny teeth that can cause painless cuts, and people, especially small children, may not even realize they have been bitten.