Delta is coming. But contrary to alarmists at home and abroad, there is little reason to panic.
Scientists first identified the Delta variant of the COVID-19 virus in India. Since then, it has been detected in more than 80 countries and is rapidly becoming the dominant strain in most. It is substantially more transmissible than other variants. This has led public-health authorities to reimpose or extend mask mandates and other restrictions.
But they’re overreacting.
In Israel — the most thoroughly vaccinated nation in the world — a small bump in new COVID-19 cases, mostly Delta, led the authorities to re-impose indoor mask requirements and to delay allowing foreign tourists to enter. Britain, which also has high vaccination rates but a high prevalence of Delta cases, pushed back the easing of restrictions by a month.
Several countries are limiting British travelers, even the vaccinated. The World Health Organization, citing Delta concerns, has urged even vaccinated people to wear masks and continue other precautions.
On this side of the Atlantic, Los Angeles County authorities, citing a high prevalence of Delta variants among COVID-19 infections, recommended that everyone wear masks indoors in public — regardless of vaccination status.
Surprisingly, the most reasonable response to Delta has come from the normally ultra-cautious US Centers for Disease Control and Prevention. Even though the Delta variant has become the most common strain circulating in the United States, CDC Director Rochelle Walenksy said that vaccinated people needn’t wear masks, since the vaccines are effective against all the variants, including Delta.
Scientific evidence backs this up: COVID-19 vaccines are highly effective in general and against Delta, as well. A just-published study in the New England Journal of Medicine, focusing on a population of health-care and other front-line workers, confirmed earlier reports that two doses of the Moderna and Pfizer vaccines were 91 percent effective in preventing infection; a single vaccine dose was 81 percent effective.
Equally important, the few vaccinated participants who were infected had less severe and shorter illness than unvaccinated people and had much less detectible virus, suggesting they would pose a lower risk of transmitting the virus to others.
Preliminary data from Public Health England indicate that one or two doses of the Pfizer or Astra-Zeneca vaccines are roughly as effective in preventing hospitalizations in people infected with Delta as with earlier variants. Moderna announced that its vaccine makes neutralizing antibodies to all known SARS-CoV-2 variants, including Delta. A Pfizer official in Israel reported that its vaccine is 90 percent effective in preventing COVID-19 disease.
As with earlier variants, vaccinated people infected by Delta will likely suffer mild cases and pose minimal risk to others. Delta poses the greatest risk to those who remain unvaccinated. Delta cases in Britain have primarily been in unvaccinated, younger age groups.
While a Scottish study published in the journal Lancet found a higher risk of hospitalization with Delta infections than earlier variants, the effect was concentrated in those with five or more relevant comorbidities — a group already known to be at higher risk of severe COVID-19 disease. Thankfully, the UK data show hospitalizations and deaths increased at a much lower rate than infections.
The accumulating evidence bodes well for US regions where vaccination is widespread. COVID-19 disease severity and mortality are highly correlated with advancing age. It is rarely a severe disease in people under 18, and deaths in that age group account for only 0.1 percent of COVID-19 deaths. Indeed, severe disease in people under 50 is rare unless they have comorbidities.
Fifty-five percent of Americans 12 and older —the group that vaccines are authorized for — are fully vaccinated, and 64 percent have received at least one dose. Importantly, in the most vulnerable population 65 and older, four in five have been fully vaccinated, and nine in 10 have received at least one dose. Despite rising Delta prevalence, new COVID-19 cases, hospitalizations and deaths continue their steady decline.
The bottom line is that Americans should get vaccinated — not panic. At worst, the Delta variant will cause localized outbreaks in areas where vaccination rates remain low. But these cases will likely be concentrated among younger people who are far less likely to get severely ill or die.
Joel Zinberg, M.D., is a senior fellow at the Competitive Enterprise Institute.