Dallas County may achieve herd immunity in the summer, but that does not mean things will be normal again

With the increase in vaccinations and new cases of COVID-19 declining in many parts of the country, the end of the pandemic may seem in sight. Many experts have predicted that the country will start moving between late spring and autumn at some point.

But what does normalcy look like? How will we know when we get there?

And how will Governor Greg Abbott’s decision to end coronavirus restrictions across the country affect the timeline?

Before the country can return to normal, enough of the population must develop resistance to the coronavirus to stop its spread.

Experts have set the threshold, known as herd immunity, at about 80 percent of the population. Recently, experts from the Parkland Center for Clinical Innovation, or PCCI, predicted that Dallas County could reach herd immunity by the end of June.

Abbott’s decision to lift coronavirus restrictions – to end a mask mandate and open businesses to full capacity – does not change the projection, say scientists at PCCI. But the move could shift the burden of disease to vital workers who have not yet been vaccinated, other experts have warned.

Many people equate herd immunity with normalcy, but the two are not the same, said Dr. Holt Oliver, PCCI, said.

With herd immunity, ‘your infection will be much lower’, he said. “But that does not mean that everyone should just take off their mask when we get to that place.”

When Dallas County reaches herd immunity, the virus will continue to circulate, but the risk of large increases overwhelming hospitals will be significantly reduced.

Normality will only resume when the number of confirmed and probable new cases falls below 14 per 100,000 or 27 new cases per day for 14 consecutive days, according to the COVID-19 response measurements in Dallas County. The country’s current infection rate is 21 new daily cases per 100,000, or 697 total daily new cases, placing it in the second “orange” category of community transmission, according to a database from Brown University’s School of Public Health.

According to the province’s definition, even normality is not the same as life before the pandemic. The public guidance for the ‘new normal’ calls for continued masking, social distance and hand washing when eating in restaurants, shopping in stores and attending large gatherings.

Experts also point out that herd immunity is not a permanent condition. “It’s a liquid state,” said Dr. Michael Mina, an epidemiologist at the Harvard TH Chan School of Public Health, said. “It comes and then it can go.” Mina said immunity among those infected early in the pandemic or vaccinated in early 2021 could decline with the decline, potentially causing new waves of cases.

Coronavirus variants can also undermine herd immunity. The Centers for Disease Control and Prevention have identified three key variants. The one is a highly contagious strain first identified in the UK. Two other strains, one first identified in South Africa and one first detected in Brazil, spread more rapidly and can also infect people who have been vaccinated or recovered from previous cases of COVID-19.

Last week, Houston became the first city to report finding all three variants of concern among its patient samples.

“It seems likely that we will have to constantly update the vaccines,” said Spencer Fox, a pandemic expert at the University of Texas at Austin. “I’m not sure about the frequency, but it might look like seasonal flu.”

Dr. John Carlo, former medical director of Dallas County Health and Human Services, said the new coronavirus could act more like measles. The measles virus circulates at very low levels and returns to their pockets when vaccination rates or herd immunity decline.

Experts from PCCI recognize that herd immunity can fade and return. Their prediction depends on the vaccination rates of at least 65,000 new shots per week and lasting immunity.

According to PCCI, 45.5% of Dallas County residents had immunity to the virus on March 1st. Between the end of June, PCCI expects that 130,000 adults and children (5% of the population) will be newly infected with COVID-19 and that approximately 1 million, or 40% of the population, will be vaccinated.

Steve Miff, PCCI’s president and chief executive, said he did not think Abbott’s decision to end the coronavirus restrictions in Texas would significantly affect the center’s projections.

“If there is anything, we can get to the immunity levels of the herd faster, but it is safe for no one to get there by more people being infected,” he said. “We can and should get herd immunity through vaccinations.”

Dr. Philip Huang, director of health and human services in Dallas County, said in an interview that matters could bounce back, similar to the way it happened after Memorial Day weekend, after Abbott lifted the state’s initial exclusion.

“There are still a lot of people who are not vaccinated and remain unprotected,” he said.

Along with its forecast, PCCI released a map showing the estimated percentage of people in each North Texas zip code with an immunity to the coronavirus. Rates range from 5.6% in the 75067 zip code north of Coppell to 69.6% in downtown Dallas’ 75202 zip code. Miff said PCCI has no insight into what the different rates represent.

Huang said the zip code would be useful in identifying priority areas for vaccinations.

Carlo added that frontline workers and those with the least access to vaccines will bear the brunt of any new congestion.

“This is completely unfair to those in the essential workforce who have not yet been able to get the vaccines, and are now more exposed to people entering their grocery stores and restaurants and bars without their masks,” he said. “It’s really unfortunate that we could not wait a little longer to get these people vaccinated.”