01 Jul The Shingles Vaccine Controversy
Reactions to the Zostavax shingles vaccine inspired dozens of lawsuits, and now the CDC recommends rival Shingrix. But should you get it?
Shingles is a painful viral infection that causes a rash, usually as a mass of blisters wrapping around the right or left side of the torso. A million cases of the disease occur in the U.S. every year, and the risk rises with age. Shingles is caused by the same varicella-zoster virus that triggers chickenpox. Once you’ve had chickenpox, the virus remains dormant in nerve tissue and can reactivate in the form of shingles years later. Anyone who has ever had chickenpox can come down with shingles. Many experts anticipate that half the population over age 80 will develop shingles.
Approved by the U.S. Food and Drug Administration (FDA) in 2006, Zostavax shingles vaccine was recommended to those 60 and older. The live vaccine is given as a single injection in the upper arm. But many who got the shot say it gave them shingles, or non-shingles related injuries, due to the live virus in Zostavax. Hundreds of product liability claims are pending against drug maker Merck & Co. from those who got the vaccine. Plaintiffs allege that the vaccine caused them to develop a more severe, painful and less treatable form of shingles than the one they were trying to avoid, as well as other auto-immune disorders.
Chickenpox Exposure Affects Shingles
Before children were routinely vaccinated for chickenpox, exposure to the disease helped protect adults who had already had it from developing shingles. Many countries have previously avoided universal vaccination against chickenpox in childhood because of a belief that the rise in shingles cases would outbalance the dip in chickenpox disease. This is one argument against vaccinating children for chickenpox.
In the U.S., Gary Goldman, Ph.D., served as a research analyst for the Varicella Active Surveillance Project in a cooperative project with the CDC from 1995 to 2002. He believed having chickenpox in a population protected against shingles. In his resignation letter, he stated that “When research data concerning a vaccine used in human populations is being suppressed and/or misrepresented, this is very disturbing and goes against all scientific norms and compromises professional ethics.” In 2005, Goldman published a paper giving evidence that shingles is suppressed naturally in human populations by repeated exposure to naturally occurring chickenpox.
However, while experts used to think this asymptomatic boosting lasted up to 20 years, a recent study by researchers from the Universities of Antwerp and Hasselt (Belgium) shows the protection only endures for two years. The only age group that appears to show an uptick in shingles cases when a population vaccinates children against chickenpox is 31 to 40-year-olds. Therefore, scientists have concluded that the benefits of the chickenpox vaccine for children outweigh the risks.
“We were surprised to find that re-exposure to chickenpox is beneficial for so few years and also that the most pronounced effect of vaccination on increasing cases of shingles is in younger adults,” says lead author Dr. Benson Ogunjimi. “Our findings should allay some fears about implementing childhood chickenpox vaccination,” he says.
In 2017, the FDA approved a new vaccine for shingles, Shingrix, that is 90 percent effective at protecting against the virus. Developed by GlaxoSmithKline, Shingrix is different from most other vaccines, including Zostavax. Shingrix is made from a single protein that comes from the outer shell of the herpes zoster virus, rather than a weakened form of the whole virus. And the vaccine contains something called an adjuvant that helps your body fight the virus.
As people get older, their natural immunity declines, leaving them more susceptible to disease. This is often when the dormant chickenpox virus attacks, causing stabbing pain and flu-like symptoms.
A new study included more than 15,000 people in 18 countries who got two doses of the vaccine, two months apart. Participants were from Europe, North America, Latin America, Asia and Australia.
“The second dose of the vaccine is important to ensure long-term protection,” says lead researcher Professor Tony Cunningham from the Westmead Institute for Medical Research. “The efficacy is approximately 90 percent for all age groups, even for those over 70 years of age.
“This is quite remarkable because there are no other vaccines that perform nearly so well for people in their 70s and their 80s. We are seeing results comparable to those of childhood vaccinations. What’s particularly exciting, though, is that 90 percent of recipients had an increased immune response sustained across the three-year duration of the study.”
The study authors anticipate that protection will endure “much, much longer” than four years with the addition of the second recommended vaccine dose, given two to six months after the first.
CDC Switches to Shingrix
The Centers for Disease Control and Prevention (CDC) has promoted the use of Zostavax for years in spite of drawbacks. According to the manufacturer product insert, Zostavax “does not result in protection of all vaccine recipients. The duration of protection beyond four years after vaccination with Zostavax is unknown.” Studies found a significant decrease in vaccine effectiveness one year post-vaccination, and by nine years, Zostavax offered no protection. According to the CDC, Zostavax was effective in reducing shingles by about half (51 percent) in adults age 60 and over.
As of 2018, the CDC dubbed Shingrix the preferred vaccine for shingles. Additionally, the longer protection time of Shingrix caused the CDC to change its starting recommendation from age 60 to age 50 for the newer vaccine.
However, Shingrix comes with a downside. It’s more likely to cause unpleasant side effects than Zostavax, according to Dr. Kathleen Dooling, a medical officer in the division of viral diseases at the CDC.
“One of the important things is to go into this vaccination knowing that you’ll probably have some side effects after and be prepared for those,” Dooling says. “The advice we’ve been giving people is that if you plan to get the vaccine, in the day or two afterwards, don’t plan any big, strenuous activities. For example, don’t plan a big gardening project … don’t plan your big golf game for that period.”
Your arm is likely to be sore in the day or two after vaccination. Eighty percent of people reported injection-site pain, redness or swelling. You may also experience general flu-like symptoms such as tiredness, nausea, headache, shivering, muscle aches and fever. Taking an over-the-counter medication for pain would be “a reasonable thing to do,” Dooling says.
Three percent of “adverse events” related to Shingrix and reported through the Vaccine Adverse Event Reporting System were serious, out of about 3.2 million doses administered in the first eight months of the new vaccine’s use. It’s “not different from what we would expect for any new vaccination,” according to Dooling.
Who Should Get Shingrix Vaccine
People who are in good health age 50 or older should get vaccinated with Shingrix, according to the CDC. While you can’t get shingles if you’ve never had chickenpox, more than 99 percent of Americans over the age of 40 have had the disease. People should get the Shingrix vaccine even if they’ve gotten the Zostavax shot in the past or have already had shingles.
It’s important to get a second dose of Shingrix within two to six months after the first shot. It may trigger another bout of side effects, and those could be different than any you got from the first shot.