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Many countries have given us a preview of what’s to come with COVID subvariant BA.5. Prepare.

Our fate over the next few months will be defined by not only the behavior of BA.5 and emerging subvariants, but by human behavior.

A woman in Nicosia, Cyprus, Jan. 19. Cyprus has brought back compulsory mask-wearing in all indoor areas for everyone age 12 and over following a surge of COVID-19 infections. The government said Wednesday the infection spike is in line with a global trend that's mainly owed to the BA.4 and BA.5 variants of the coronavirus.Petros Karadjias/Associated Press

The BA.5 Omicron subvariant is here and is the dominant COVID-19 virus in the United States. Case positivity rates have been higher than they are now only twice since the beginning of the pandemic — during the first weeks of the pandemic, and a few weeks during the January 2022 Omicron spike.

Many countries have given the United States a preview of what’s coming with BA.5. Portugal is one of the most highly vaccinated countries, yet BA.5 has completely overwhelmed it. ICU admissions in Israel are going “vertical,” with similar effects in many European countries and rapidly increasing case numbers around the world. Though the severity of BA.5 compared to previous variants is unclear, there is a worrying uptick in US hospitalizations, including a growing national trend of rapidly increasing pediatric COVID hospitalizations.


Though we have faced waves of several different variants since the original strain was first detected in Wuhan, BA.5 is a new beast with a host of challenges that we have not seen before. Not only does BA.5 have critical mutations in its spike protein, it also has numerous non-spike mutations in other areas of the protein, allowing it to largely evade immunity from prior infection (even recent infections), prior vaccination (even with boosters), and “hybrid immunity” — a combination of vaccination and infection that was believed to denote a higher degree of protection, but is unable to prevent reinfection from BA.5. COVID-19 vaccination is still expected to provide substantial protection against severe disease leading to hospitalization and death. However, it is far less effective at preventing infection and transmission now than it once was, and every infection and reinfection is accompanied by the risk of long COVID.

Our fate over the next few months will be defined by not only the behavior of BA.5 and emerging subvariants, but by human behavior. For the most part, mandates have disappeared in the United States and are unlikely to return. With the prevalence of pandemic fatigue, it is also doubtful that universal masking will return, no matter how large the surge.


Over the next few months, either BA.5 will infect so many people that it will burn itself out, or it will be replaced by a variant that is even better at infecting people. High-quality masks (N95/KN95), proper ventilation, physical distancing, and air filtration would help, but it seems unlikely that leadership at the local, state, or federal level will act on the coming BA.5 COVID-19 wave unless hospitals again become overwhelmed. Boosters would also help, but only about 1 in 4 of those 65 and older who received the first booster have received the second. A second booster will not protect fully against reinfection, but it significantly reduces the risk of dying from COVID-19 — especially for those over the age of 50. People who can get a second booster, absolutely should.


If you're not being strict with your mask wearing & other infection control measures, now would be a good time to start

♬ Take my Time 2K19 by Vivid The Producer - JLW

The ever-changing nature of the pandemic means that there is a constant flow of new information, as well as endless opportunities for misinformation to spread — from the distortion of facts on vaccine safety and effectiveness to ignorance about long COVID and misconceptions about new variants. I am a part of Team Halo, a global team of scientists and vaccine experts working with the United Nations to combat COVID-19 vaccine misinformation. As we learn about new variants and gather additional details about vaccine effectiveness, I use social media platforms like TikTok (@dr_asherwilliams) to bring updated information to the public and educate and engage those who get their news mostly through social media. When people choose not to get vaccinated or disregard public health measures based on inaccurate information, they put the health of many at risk — leading to premature and preventable deaths in some cases. The fight to educate the general population is an often overlooked but vital component of public health.


On the horizon, we have Moderna’s Omicron bivalent booster vaccine candidate with promising data recently released showing higher efficacy against all variants of concern, including BA.5, compared to current boosters. Keep in mind that it took more than seven months for the bivalent Omicron booster to be tested. Meanwhile, this virus continues to outrun us. The time between new variant waves is becoming shorter as new versions of the virus continue to accelerate, and our rollout of adapted vaccines, clinical trials, and the Food and Drug Administration authorization timeline is racing to keep up with this furious pace. More focus should be placed on developing universal vaccines that are variant-proof and can protect against a wide range of coronaviruses.

Additionally, there needs to be further exploration of nasal vaccines, which harness the protective benefits of mucosal immunity and can deliver vaccines directly to the site where the virus first makes contact. In the meantime, it is up to each of us to determine our own risk tolerance, individually and as families, and use this to govern our behavior. If you’ve already had COVID, this is no excuse to throw caution to the wind as there is now evidence that long COVID risk increases with each reinfection.


Regardless of COVID-19 history and vaccination status, everyone will need and benefit from reinfection prevention strategies like universal masking while vaccine-makers are working on updated shots. Unfortunately, variants have changed the game for us and BA.5 is yet another COVID challenge to be dealt with.

Asher Williams is a postdoctoral fellow at Cornell University and incoming professor of chemical engineering at Columbia University.