COVID-19 Vaccinations: Answering Your Questions

As COVID-19 vaccination efforts continue, there are many questions about the vaccines in use, the current status of the vaccination campaign, and the effects of vaccines on the trajectory of the pandemic. Jason L. Schwartz, Ph.D., an assistant professor in the Department of Health Policy and Management, has been a leading national voice on COVID-19 vaccination policy throughout the pandemic and an advisor to Connecticut Gov. Ned Lamont during the state’s successful COVID-19 vaccination program. Recently, he answered several frequently asked questions about the vaccines and the impact of increasing rates of vaccination.

Where do things currently stand with COVID-19 vaccination in the United States? What are the major challenges ahead?

J.S. The vaccination program is at a transition point. The phase when vaccine supply was limited and eligibility for vaccination was restricted to specific populations has ended. With ample vaccine supply now available, we must now turn our attention fully to the nearly 50% of the adult population that has not yet received the vaccine. This includes people who encountered barriers when attempting to schedule a vaccine appointment or traveling to a vaccination site, as well as those who may have questions or concerns about the safety and importance of the vaccines. The pace of vaccination will slow in the coming weeks and months compared to what we’ve seen thus far, but reaching a large percentage of this unvaccinated population is critical to an equitable vaccine rollout and control of the pandemic in the months ahead.

The Johnson & Johnson vaccine has been in the news recently following a “pause” due to reports of rare adverse events among a small number of people who received the vaccine. Should the public be worried about the safety of this vaccine or the other COVID-19 vaccines?

No medical intervention is more extensively monitored for potential safety concerns than vaccines, and COVID-19 vaccines, in particular, have received unprecedented, ongoing scrutiny from public health officials. It was through that careful examination that a small number of potentially serious blood clots were identified among the millions of individuals who received the Johnson & Johnson vaccine. That observation prompted government health officials to briefly pause use of the vaccine in the United States while that risk could be studied, and appropriate steps taken to educate the public and health care providers about it. After a thorough review that confirmed the rarity of the risk and the overwhelmingly positive risk-benefit profile of the vaccine, the pause was lifted on April 23, and the vaccine is now available once again as an option alongside the Pfizer and Moderna COVID-19 vaccines. The seriousness, rigor and transparency with which this issue was examined should reassure the public that confidence in the safety of the vaccines is well deserved.

Can vaccinated people still get COVID-19? How long does vaccine immunity last? Do the currently available vaccines protect against variants?

We know a tremendous amount about the currently available vaccines, evidence that has led us to be confident and enthusiastic about their safety and effectiveness. But as more and more vaccines are administered, we continue to learn more about them, as is the case with every medical and public health intervention that is implemented. The effectiveness of the COVID-19 vaccines has exceeded nearly all expectations, but no vaccine is 100% effective, and there have been extremely rare cases in which vaccinated individuals have subsequently tested positive for COVID-19. But those cases were generally mild, and they’ll become even less frequent as vaccination rates continue to increase.

We don’t yet know precisely how long protection lasts following vaccination, but it’s thought to be at least six months – and likely considerably longer. That duration is being carefully monitored in case booster doses are needed for COVID-19 vaccines, as they are for other diseases. Regarding protection against variants, the vaccines look to be faring very well so far against the most concerning variants, but this, too, requires ongoing attention. In the meantime, vaccinating as many individuals as quickly as possible is unquestionably our best tool to protect ourselves and our communities.

Do people still need to wear masks and practice physical distancing after they are vaccinated?

When COVID-19 vaccination was just getting underway, our message to the public was to view the vaccine as an addition – not a replacement – to all of the other strategies important to reducing the spread of the disease, including masks, physical distancing and limits on large gatherings, especially indoors. Now that significant portions of the population have been vaccinated – including a large majority of the highest-risk groups – and hospitalizations and deaths are declining, updated guidance from public health officials is increasingly relaxing some of those recommendations. Masks continue to be prudent for many indoor settings, particularly public venues where large groups are assembled. On the other hand, smaller gatherings of vaccinated individuals, most especially outdoors, are thought to be fairly low-risk, and so we can look forward to further relaxation of the public health precautions we’ve all grown familiar with over the past year as vaccination rates continue to increase.

Jason Schwartz, Ph.D., is an assistant professor in the Department of Health Policy and Management, an assistant professor in the History of Medicine, and an assistant professor in the Institution for Social and Policy Studies at Yale University.

This commentary is part of a series produced by Yale School of Public Health highlighting important issues related to COVID-19 and public health.