Vaccine Safety. How Much do We Know?
The Johnson & Johnson’s vaccine pause in the US
The US health authorities recommended pausing the distribution of Johnson & Johnson’s vaccine to investigate cases of blood clots in women, including one death.
Although the cases are rare, the US Food and Drug Administration, regulators, and researchers still don’t know if it was the vaccine or something else causing these effects in women from 18 to 48 years old and the recommendation is to keep track of symptoms for those who took it within the last 2 weeks. For those who received a dose more than a month ago, the risk of blood clots is very low.
Nearly 7 million people in the US received a single dose of the Johnson & Johnson vaccine. Dr. Janet Woodcock, the acting commissioner of the F.D.A. says the pause will only last a few days, although this time frame depends on what we learn in the next few days. This is necessary to validate these findings and prepare the health care systems to recognize adverse events and treat patients appropriately.
The Broader Picture
As of Sunday, April 11th, 2021, about 119.2 million people in the US have received at least one dose of a COVID-19 vaccine. Before vaccines releases, data was already being collected in clinical trials to demonstrate the safety and efficacy - and it is crucial that data keeps being collected during the vaccine roll-out as a continuous process to reevaluate what we know about their long and short-term effects and help ensure the safety of our communities.
Long- and Short-Term Symptoms of COVID-19 vaccines
The new surveillance system collecting data from COVID-19 in the US launched by The Center for Disease Control and Prevention (CDC) includes data on the effectiveness of COVID-19 vaccines and monitors short and long-term symptoms of the vaccine. Using text messages to communicate with vaccinated individuals, data shows that individuals receiving the Moderna vaccine reported a higher number of symptoms as opposed to those who received the Pfizer-BioNTech vaccine. Findings are based on data collected from approximately 3.6 million people in the US who received their first dose of a vaccine before February 21st.
After receiving the first dose of Moderna vaccine, recipients reported:
73% reported injection-site reaction.
51% reported full-body symptoms.
On the other hand, Pfizer recipients reported:
65% injection-site reaction.
48% full-body symptoms.
A similar trend was reported in response to the second dose, where Moderna recipients had a higher prevalence of reporting symptoms.
Fortunately, current data on post-vaccination symptoms remains unalarming and these effects are considered a normal reaction of the human immune system, according to immunology experts. However, there is a strong call to maintain the current monitoring efforts in both the short and long term. This includes tracking symptoms, analyzing the data collected, interpreting, and comparing it among the different available vaccines. This data can direct intervention measures, policymaking, and shape future strategies for vaccine production and administration.
To be able to monitor how vaccines behave in the human body over time, it is necessary to collect data, track, evaluate, process and inform policies that will improve the planning for potential future outbreaks. The Aztute public health platform allows public health agencies to collect accurate and reliable data from the community, in any phase of a public health crisis.