Rabies: The Deadliest Disease in the World Kills 160 People Every Day

Rabies has always been seen as something of an enigma in the healthcare world. An uncommon disease, rabies has all but disappeared in developed worlds. However, its capacity to quickly and mercilessly kill its victims - even those treated with modern medicines - has made it seen as the deadliest disease in the known world. Now new data has revealed that it's not nearly as uncommon as thought, killing a stunning 160 people every single day.

That's at least according to a study recently published in the aptly named Public Library of Science's (PLOS) journal Neglected Tropical Diseases.

"This ground-breaking study is an essential step towards improved control and eventual elimination of rabies," professor Louis Nel, Executive Director of the Global Alliance for Rabies Control (GARC), said in a statement. "An understanding of the actual burden helps us determine and advocate for the resources needed to tackle this fatal disease."

The GARC-led study specifically shows that although this disease is preventable and (somewhat) treatable, around 59,000 people die every year of rabies transmitted specifically by dogs. (Scroll to read on...)

So Just What is Rabies?

Before we delve into the implications of the study's numbers, it might be a good idea to remind you what rabies does. With a nearly 100 percent mortality rate even in developed worlds, it seems silly to think that rabies is a disease we'd soon forget. However, few actually know how it kills, especially with diseases boasting far lower mortality rates (50-60%), like Ebola and Middle Eastern Respiratory Syndrome (MERS), taking the spotlight for the last year.

According to the US Centers for Disease Control and Prevention (CDC) "the first symptoms of rabies may be very similar to those of the flu including general weakness or discomfort, fever, or headache. These symptoms may last for days."

At this point, a patient may start treating that flu, but unfortunately, this won't be enough.

What makes rabies different than other viruses is that it doesn't use the blood stream to help it spread its infection cell-by-cell. Instead, it grabs the first nerve it can and climbs the human nervous system like a ladder (progress is estimated to be about 1 to 2 cm a day) until it finds its way into the brain. It can only be transmitted via the saliva of a rabid animal bite, and its progression can be halted if a vaccine is administered soon after a victim is bit. However, once the virus reaches the brain...

"There are videos online where you can see people [with rabies] in this state," RadioLab producer Tim Howard said in a chilling episode of the popular podcast. "I find them impossible to watch."

You can certainly find these videos for yourself, but due to their graphic nature, NWN will not post them here. Simply said, the virus drives its victim mad with discomfort, insomnia, cerebral dysfunction, delirium, and fits of rage to the point that they seem inhuman. (Scroll to read on...)

"From the viruses prospective, it's trying to drive it's host to be more aggressive so that they bite somebody else and spreads more virus," Howard explained.

And because researchers are unsure how exactly the virus does this (all they know for sure is that cognitive function decays), reaching this state is essentially a death sentence.

Getting Fido Fortified

That's why experts have been struggling to ensure that no one is bit by rabid animals in the first place, calling for a One Health approach - a recognition that human health is tied in with the health of animals and their ecosystems.

"Rabies is close to 100 percent fatal, but it is also almost 100 percent preventable, and the best, most cost-effective way of preventing canine rabies is by vaccinating dogs," GARC spokesperson Kevin Doran added.

It should go without saying that it is far less likely that humans will be bit by bats (one of the primary vectors of the rabies virus) compared to dogs. Likewise, domestic dogs, when rabid, are very likely to bite their owner. This then explains some of the GARC paper's latest figures, with countries that have invested mostly in dog vaccination being the ones where human deaths from the disease have been virtually eliminated.

In the United states, for instance, pet owners are required to have their pets immunized for rabies every three years, with some states asking for annual vaccinations. Thus, more than 90 percent of animal cases (reported by the CDC) now occurrs among wildlife. Before the vaccination mandates were in place, the majority was among domestic animals. (Scroll to read on...)

[Credit: GARC]

The new GARC paper also details how the death rate for rabies is highest in countries in sub-Saharan Africa, while India has the highest number of fatalities, with over 20,000 human deaths annually.

"The proportion of dogs vaccinated is far below what's necessary to control the disease across almost all countries of Africa and Asia," Doran explained.

Unfortunately, the rabies vaccine does not come without risk, which is why human administration only occurs in rare and desperate instances. Some of the most severe known side effects include seizures, epilepsy, a harsh autoimmune reaction, and even cancer at the injection site.

Still, these latest findings bolster the argument that the benefits of canine vaccination heavily outweigh the risks.

"No one should die of rabies and GARC and its partners will continue to work together using a One Health approach towards global rabies elimination," Nel concluded.

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