The Food and Drug Administration (FDA) has officially approved new, updated COVID-19 vaccines from both Pfizer and Moderna, marking the third revision of these vital immunizations. These latest vaccines are specifically engineered to target currently circulating strains of SARS-CoV-2, including the KP.2 strain mentioned in initial reports and the XBB.1.5 Omicron subvariant, demonstrating a strategic effort to enhance protection against evolving viral threats.

Peter Marks, MD, PhD, director of the FDA’s Center for Biologics Evaluation and Research, underscored the ongoing importance of vaccination, stating that it "continues to be the cornerstone of COVID-19 prevention." He affirmed that the updated vaccines meet the agency’s stringent scientific standards for safety, effectiveness, and manufacturing quality. Given the observed waning immunity within the population, the FDA strongly encourages eligible individuals to consider receiving these updated vaccines for improved defense against current variants.

Thomas Russo, MD, a professor and chief of infectious disease at the University at Buffalo in New York, identifies the Pfizer and Moderna mRNA vaccines as the most current options available, explaining their refinement to more closely target contemporary circulating strains and provide enhanced protection against serious infection. He noted that the Novavax vaccine is not yet ready for this update. The FDA and Centers for Disease Control and Prevention (CDC) currently recommend that everyone aged 6 months and up receive the new vaccine, with specific guidance for timing: high-risk individuals should get vaccinated as soon as possible, while others are advised to receive it by Halloween. For those recently infected with COVID-19, a waiting period of three months from the time of infection before vaccination is suggested.

Regarding availability, pharmacies are in the process of transitioning to the new stock. CVS has indicated it is removing the 2023-2024 COVID-19 vaccine from its inventory and awaiting the new version, though appointments for the near future can be booked. Walgreens, on the other hand, had not yet updated its website to reflect the new vaccine at the time of reporting. Dr. Russo estimates it will likely take about a week or so for the shots to become widely available at pharmacies once Pfizer and Moderna have the green light for distribution.

The cost of the new COVID-19 vaccine can vary. While most health insurance companies are expected to cover the vaccine fully, uninsured adults may face out-of-pocket expenses. Dr. Russo pointed out that public health programs that previously covered vaccine costs for adults are no longer funded. However, children typically remain covered through various pediatric vaccination programs. For uninsured adults, the CDC recommends seeking free vaccination through local health centers or pharmacies participating in the CDC’s Bridge Access Program, which aims to reduce financial barriers to care.

As for the current landscape of the virus, COVID-19 cases and hospitalizations are on the rise again with cooler weather, and new variants are continually emerging. Data from the CDC shows several variants circulating, including EG.5, nicknamed "Eris," which became the most common variant in the U.S. over the summer, accounting for nearly 25 percent of infections. Eris is considered a "grandchild" of Omicron, known for its high infectivity. Another variant, BA.2.86, or "Pirola," is also under monitoring by the World Health Organization (WHO), despite fewer reported cases globally.

The new COVID-19 boosters appear to offer protection against these emerging variants. Preliminary data from Pfizer and Moderna indicates a significant increase in neutralizing antibodies against both EG.5 and BA.2.86. A key distinction of these new boosters is their monovalent nature, meaning they target a single strain of SARS-CoV-2 (XBB.1.5), in contrast to the previous bivalent vaccines that targeted multiple strains.

Dr. Russo emphasizes the effectiveness of these updated shots, noting they are better matched to circulating variants than earlier versions. Boosters have been shown to strongly protect against severe COVID-19 and death, and to a lesser extent, prevent infection. Their impact is particularly dramatic for high-risk individuals, such as older adults and immunocompromised people. He likens the approach to the annual flu vaccine, where scientists update the formula each year to anticipate the most common variants. Although clinical data for the exact percentage effectiveness against the virus is not yet available, the expectation is for a good match.

The names of the updated vaccines remain Comirnaty (Pfizer) and Spikevax (Moderna), with this year's version simply referred to as the "2023-2024 formula." Side effects are similar to those experienced with previous COVID-19 vaccines, including pain, swelling, and redness at the injection site, fatigue, headache, chills, muscle pain, joint pain, and fever.

For individuals considering concurrent vaccinations, it is acceptable to receive the COVID-19 booster and the flu shot at the same time. However, Dr. Russo advises that if time permits, separating the vaccinations by a week or two might be beneficial to mitigate the potential for a "double whammy" of side effects, especially for those who have experienced notable reactions in the past. Despite lingering questions and the evolving nature of the virus, Dr. Russo strongly recommends getting vaccinated, reiterating that "there is still a lot of COVID going around."