A comprehensive review of 20-year data has found that thanks to ongoing safety monitoring after the US vaccine hit the market, according to an Israeli study published Monday in the Annals of Internal Medicine.
The study’s lead author stated, “Our study suggests that even though a potential vaccine does not have rare or long-term side effects in clinical trials, a monitoring program is in place to identify those issues.” Dr. Daniel Shepshlovich, Head of Internal Medicine at Tel Aviv Sorsky Medical Center.
“Most such studies show a complex picture, but here, we saw almost no complexity,” he said. “Vaccines are safe.”
Compared to similar studies Shepashilovich has done on medical interventions, new studies show that vaccines are safer than many drugs, which can be beneficial but often come with side effects.
“Vaccines have almost no side effects and are especially safe compared to medical devices,” he said.
In the study, researchers used data from the Vaccine Advanced Event Reporting System, or VARS, a database created in 1990 by the Food and Drug Administration and the Centers for Disease Control and Prevention. The national surveillance system collects approximately 30,000 reports each year from health professionals, vaccine manufacturers, and the public concerning potential vaccine safety concerns. The FDA continuously monitors reports to find patterns or spikes in adverse events reported about a particular vaccine.
Researchers investigated post-approval safety issues, with VAERS picking up 57 FDA-approved vaccines between January 1996 and December 2015. Most of the newly approved vaccines were annual flu shots. The team found 58 post-market safety-related label changes involving 25 vaccines and prescribed changes of limited importance.
Approximately 40 percent of the updated safety guidelines were related to prohibiting the use of the vaccine in some groups, such as people not vaccinated, pregnant women and preterm infants who were removed by not giving the vaccine. The second most common update, accounting for more than 20 percent of post-market modifications, was related to allergies, almost always to latex packaging.
About 20 percent of the safety modifications were related to patients’ unconsciousness after receiving the vaccine, although Shepashlovich stated that those who feared the needle may have had side effects instead of the vaccine. Five percent of the update actually removed previous warnings and precautions, and only one vaccine for rotavirus, was recalled in 1999.
This study actually shows once again that vaccines are one of our safest interventions.
“This study actually shows once again that vaccines are one of our safest interventions,” said Tara Smith, a professor of epidemiology at Kent State University in Ohio. “The issues they saw were largely correct, only they can change what vaccines they give.”
Smith, who was not involved in the new research, said that some safety concerns that have not caught on during clinical trials are that phase 3 clinical trials involve thousands of people, rather than the millions who are vaccinated. Once it is part of standard practice.
“Even the largest clinical trial that we still have, which will be smaller than the number of people receiving the vaccine after it is used in the population,” she said. “Post-approval monitoring may show minor issues in some populations that were missed in early clinical trials but are still caught up over time.”
Indeed, this is why strong safety monitoring programs are necessary, with Dr., director of the Vaccine Education Center at the Children’s Hospital of Philadelphia. Paul Offit, who was also not involved with the new study, said.
“The important thing is that you have systems to take on these adverse reactions, and in the US, we have many layers of systems that do this.” Monitoring programs for the COVID-19 vaccine will be particularly important, he said, because most vaccines take at least 15 years to develop and test in clinical trials, while developing a vaccine for coronovirus May take less than 18 months.
Nevertheless, Shepashlovich said that he believes the FDA will take extra precautions in monitoring the potential adverse effects of a COVID-19 vaccine as the world is paying close attention.
The office agreed. “I think the FDA and CDC would be extremely cautious about the possible side effects of the SARS-CoV-2 vaccine, as they are for every vaccine given to children,” he said. (SARS-CoV-2 is the name of the coronavirus that causes COVID-19.)
An anti-vaccine movement, however, has found support among some. Another paper published on Monday in the journal Pediatrics reported that measles, mumps and rubella vaccination rates had dropped below 90 percent in 20 states. A 95 percent vaccination rate is required to prevent the spread of measles.
“I think you should be suspicious of anything put into your body. You want to see the data, and you want to make sure that these vaccines are held at a high level.” “When you shouldn’t do that, it’s terrifying when data appears that outweigh the potential risks to vaccine benefits. The notion that the FDA or CDC is hiding something isn’t even close to the truth.”
Shepshilovich said that he understands that some people will not accept the findings of his study.
“But if you look at the facts, they are very clear,” he said. “Vaccines are safe.”
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