The US might never reach herd immunity—here’s why

Here's what you need to know about the COVID-19 pandemic this week.
People with masks walk through long hallway.
Herd immunity may be out of reach for the US. Manuel Alvarez/Pixabay

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The US continues to see a decline in daily COVID cases, hospitalizations, and deaths, but multiple variants at home and abroad are a source of concern on the path to normality. Looking ahead, new routes of administering vaccines could be on the way. Here are the latest pandemic updates.

Herd immunity is likely out of reach for the US 

The phrase “herd immunity” has long been thrown around during the pandemic, a glimmering, idealistic term for when a high enough percentage of a population is immune to provide protection for the community as a whole. But even as more than 30 percent of the US population has been fully vaccinated, experts say that herd immunity is unlikely for Americans—not now, and maybe not ever. 

This unwelcome prediction comes as vaccination rates slow down and new and dangerous variants circulate. Experts now calculate that reaching herd immunity would require 80 percent of the population to be protected via immunization or prior infection. But polls show 30 percent of adults are still hesitant to get inoculated. Experts previously estimated that 60 to 70 percent immunity would be sufficient for herd immunity, but more contagious variants raised that threshold.

“The virus is unlikely to go away,” said Rustom Antia, an evolutionary biologist at Emory University, to the New York Times. “But we want to do all we can to check that it’s likely to become a mild infection.”

While COVID-19 may be here to stay, it is predicted to become a much more manageable part of life, especially as vaccinating the most vulnerable will make future spikes less deadly. 

Vaccine shortages fuel India surge 

As India faces a devastating second wave of COVID-19, vaccine availability is extremely limited and is expected to continue that way for at least the next few months. The country has been setting deeply worrying new worldwide records for daily case rates, and on Sunday reported 401,993 new cases

Although more than 600 million Indians are now eligible for the vaccine, currently only 12 of India’s 36 states and union territories have had enough vaccines in store to start vaccinating people over 18. 

[Related: Which COVID-19 vaccine is the best?]

By Sunday, only 86,023 people aged between 18 and 45 in a country with a population of over 1.3 billion had been vaccinated. Previously, only people over 45 and those with comorbidities were eligible. 

The Indian government is also under scrutiny for acting too slowly to order vaccine doses and failing to cancel mass religious ceremonies and political rallies that may have fueled the spread of the virus. 

CVS and Walgreens have wasted over 100,000 shots 

Reports of tossed-out COVID-19 shots have been coming out since the early days of the vaccine rollout, but data from the CDC as of late March shows that US pharmacy chains are responsible for the majority of this waste. 

Of the 182,874 reported discarded doses, CVS was responsible for half of the waste and Walgreens was responsible for another 21 percent. This totals more tossed doses than most of the state-run vaccine campaigns combined. 

The Pfizer vaccine made up 60 percent of the wasted doses—it was the first to enter the market and initially required extremely cold storage temperatures. 

While it is not totally clear why this is occurring, CVS officials said that “nearly all” of its waste happened in the early stages of vaccine rollout, when the Trump administration was relying on the pharmacies to execute vaccination campaigns in long-term care facilities. 

Iowa state government declines COVID-19 vaccines 

Amid decreasing demand for vaccines, the Iowa government declined 71 percent of the supply offered to the state by the Biden administration for the upcoming week of May 10. The state is asking the feds to hold back on 75,280 doses, in addition to the 21,000 doses it declined for the current week of May 3.

This comes as 88 of the state’s 99 counties told state leadership they didn’t need their full allocated share of vaccines for next week, up from 80 counties that did the same this week. 

The state has now fully vaccinated nearly 1.1 million residents, out of a population of about 3.2 million, and nearly 57 percent of adults have received at least one shot.  

Next-generation vaccines could be pills or sprays

Phrases like “shots in arms” are currently synonymous with the COVID-19 vaccine rollout, but this could change as researchers work on innovations that could transform the way we receive this essential protection. 

Future vaccines in the form of pills and nasal sprays could make vaccine distribution more accessible in rural areas, as they would be easier to store and transport than the current shot form. 

These newer vaccines are under development by government labs and companies like Sanofi SA, Altimmune Inc., and Gritstone Oncology Inc. These companies said their new vaccines could also provide longer-lasting immune responses and better protection against emerging variants, which are likely to fuel the continued longevity of the pandemic.

Currently two pills and seven nasal-spray COVID-19 vaccines are in clinical testing, although they would likely not become available until later in 2021 or 2022, and there is no guarantee that these next-generation formulations will succeed in testing and hit the market. Around the world, 277 vaccines are in development, with 93 in the human testing stage, according to the World Health Organization.