Vaccination is one of public health’s greatest achievements, but today’s sociopolitical climate promotes unfounded fears. In turn, this fear-mongering has led to outbreaks of otherwise rare infectious diseases, such as measles and whooping cough. Human papillomavirus (HPV) vaccines protect against two HPV strains that cause 70 percent of cervical cancers, which itself is the second-most common type of cancer in women worldwide. Immunization has the potential to eliminate these viral strains, which would save lives and reduce health care costs — but, unfortunately, vaccine horror stories are a dime a dozen on the Internet, and HPV vaccines like Gardasil are popular targets for vaccine opponents.

Of 57 million Gardasil doses given in the United States, 40 confirmed deaths have occurred in recipients. However, these deaths were not caused by vaccination.

There are many claims flying around that Gardasil causes serious side effects, including death. However, claims that Gardasil can lead to death aren’t supported by good evidence. Generally speaking, people who make these accusations obtain their information from a publicly accessible database called the Vaccine Adverse Event Reporting System (VAERS), which collects claims of adverse events from anyone — including health care providers, patients, or family members.

What is an adverse event?

Most people don’t realize that the phrase “adverse event” cannot be used interchangeably with the term “side effect.” An adverse event is something that occurs after a vaccination — such as a headache, seizure, depression, or death. It could happen one second after being injected with a vaccine or more than a year afterward. It could be a coincidence, or it might be caused by vaccination. For example, if two weeks after receiving a flu shot I get a headache, I could legitimately claim it is an “adverse event,” even if my headache had nothing to do with the shot. An adverse event is only called a side effect if it is found to have been caused by vaccination.

What is VAERS?

Despite its occasional misrepresentation in print media, social media, and the blogosphere, VAERS is not a source of information about verified side effects — it is a database of adverse events that have been self-reported by the public. Anyone can submit a report to VAERS — heck, I could claim that the flu shot gave me telekinetic powers in addition to that headache, and it would be recorded in the database. That doesn’t mean that you should worry about coming down with a nasty case of telekinesis after getting a flu shot at the corner drug store.

According to the VAERS website,

for any reported event, no cause-and-effect relationship has been established. Reports of all possible associations between vaccines and adverse events (possible side effects) are filed in VAERS. Therefore, VAERS collects data on any adverse event following vaccination, be it coincidental or truly caused by a vaccine. The report of an adverse event to VAERS is not documentation that a vaccine caused the event.

If VAERS isn’t a useful source of information about side effects, what is it good for? It’s primarily used by scientists on the lookout for unusual patterns to investigate, and is integral to monitoring vaccine safety. So if you see a Facebook friend or a journalist using VAERS as a source of information about side effects, be critical, as this person probably doesn’t understand what VAERS is — or is deliberately misrepresenting it in order to stoke fear.

Have people died after being vaccinated with Gardasil?

In the United States, we’ve been keeping track of adverse events connected to Gardasil since it came onto the market. An article published in JAMA summarized the data compiled by VAERS from Gardasil’s 2006 debut through the end of 2008. The Centers for Disease Control and Prevention provided data that start where the JAMA article left off, from January 1, 2009 until March 31, 2013. All told, there have been 74 deaths following Gardasil vaccination reported to VAERS, and a total of 57 million doses of Gardasil have been distributed during this time. However, only 40 of these deaths have been confirmed. In order to verify deaths, investigators needed to get their hands on medical records, autopsy reports, or death certificates. Thirty-four of the 74 reported deaths couldn’t be verified, for example if the deceased patient or the patient’s doctor were not identified by name.

These deaths didn’t necessarily occur immediately following vaccination, either. For example, they could have occurred more than a year after the patient received Gardasil, yet still someone saw fit to file a VAERS report. Furthermore, none of these deaths was found to have been caused by vaccination. Of the confirmed deaths, no patterns emerged with respect to cause of death, number of doses received, or amount of time passed between vaccination and death. Causes of death were varied, and included bacterial infection, seizure, pulmonary embolism, prescription drug abuse, influenza, heart problems, and suicide. Of course it’s always tragic when a young person dies, but investigators did not see any red flags that might indicate that deaths following vaccination were due to anything other than coincidence.

In other words, out of the tens of millions of people vaccinated with Gardasil, some of them died — but there’s no reason to think these deaths indicate anything other than an unfortunate coincidence. In a population as large as the group of people who have received Gardasil, there are bound to be deaths — just as there are deaths among the unvaccinated population. The same goes for injuries reported to be correlated with any given vaccine. When a vaccine recipient has a problem following vaccination, these problems are usually found by investigators to be coincidental.

Is Gardasil safe?

More than 57 million doses of Gardasil have been administered in this country, and worldwide more than 170 million doses have been given. Though claims that Gardasil can kill seem alarming, we have no evidence that deaths following Gardasil vaccination were due to anything other than coincidence. Gardasil is safe, effective, and its benefits are great while its risks are small.

Planned Parenthood health centers offer Gardasil. More information is available at Planned Parenthood and the National Cancer Institute.