Herd immunity from COVID? Not going to happen. Let’s shoot for ‘herd resistance,’ instead | Opinion

COVID-19’s omicron variant of seems likely to infect almost everyone, including those already vaccinated and many of those infected by earlier variants. It is rapidly pushing the United States toward “herd resistance.” Unlike herd immunity, where new infections are minimal (think mumps or measles when almost all are vaccinated), herd resistance means that infections will continue, but almost everyone will have defenses (from vaccination, prior infection or both) that usually prevent severe disease or death.

For COVID-19, herd resistance is achievable, but herd immunity is not, given far-from-universal vaccination levels, very high infectivity and the likelihood of future mutations. Herd resistance, however, is enough to let us return to normal life.

The omicron infection spike has peaked in some states — including Florida, experts say — but collectively, we still need to take steps to reduce hospital overload and buy time so that pharmaceutical companies can ramp up supplies of treatments that can keep people out of the hospital.

What might herd resistance look like? Many of the vaccinated will have mild cases of omicron and develop stronger resistance to infection from future variants than from vaccination alone or prior infection alone. We are closer to herd resistance than many realize. About 86% of adults and 95% of the elderly are at least partly vaccinated. Many have been infected — possibly a multiple of the official count of 71 million.

For those at higher risk of serious illness, we increasingly have early treatments that can reduce that risk. The current list of effective early treatments includes the Pfizer Paxlovid pill, the monoclonal antibody Sotrovimab and, potentially, Fluvoxamine, which has performed well in clinical trials.

The unvaccinated face higher risk from omicron, but still well below the risk from the Delta variant. Moreover, there are ever fewer COVID-naïve people. A back-of-the-envelope estimate is that 10% of adults remain COVID-naïve — neither vaccinated, nor infected. For people over 65, this percentage is probably below 5%.

There is no magic bullet to get us to herd resistance. Instead, several actions can help:

▪ Healthcare professionals, especially nurses, are scarce. State legislatures can let retired providers help, despite holding expired licenses. Government pay incentives could increase the near-term supply.

▪ The CDC recently shortened the period between primary doses and booster to five months and authorized boosters for children age 12-15. But five months is still too long — vaccine efficacy against omicron infection wanes faster than that. Israel now authorizes boosters after three months.

▪ Vaccine and booster campaigns and, yes, vaccine mandates for specific groups (healthcare workers, first responders, schoolteachers) can limit spread and reduce infection severity.

▪ Stores can provide high-quality “respirator masks. Pharmacies can give them out at the entrance and offer advice on fitting them.

▪ Companies can encourage distance working. For high-risk locations such as restaurants, bars and gyms, state and local governments can impose “green passport” requirements that patrons be vaccinated, to be relaxed when the omicron surge passes.

▪ We can ask people to try to reduce contact with others for a few weeks. Every infection delayed, even for a month, helps our hospitals.

Omicron is rapidly pushing us toward herd resistance and a return to normalcy. But there are more and less-painful ways to get there. Prompt actions can still do much to reduce the pain.

Bernard Black is professor of law at Northwestern University Pritzker School of Law and professor of finance at Northwestern’s Kellogg School of Management. Martin Skladany is a law professor at Penn State University, Dickinson Law.