They Don’t Want the Shot. They Don’t Want Colleagues to Know.

Vincent Taranto has felt like less of a pariah at work in the last few days.

For more than two months, Mr. Taranto, 31, was among the only employees required to wear a mask at his job because he was unvaccinated. Though he was wary of the vaccine and skeptical that he was at risk of getting seriously sick, he was concerned that his decision to avoid the shot had left him exposed to judgment from colleagues.

“I don’t want to look like the crazy anti-vaxxer to my co-workers,” he said.

But after the Centers for Disease Control and Prevention recommended last week that Americans in high-risk areas should wear masks indoors, Mr. Taranto, who works at a large company in the outdoor industry, no longer worried that he was sticking out like a sore thumb.

“Everyone complained about it,” he said about the new masking guidelines. “And I’m like, ‘It’s not that big of a deal; I’ve been doing it the whole time.’”

Whether or not to receive a coronavirus vaccine has for the most part been a private medical decision. But as some workplaces have begun determining how to safely bring employees back to the office — drawing them from behind dissociated Zoom screens into interactive meeting rooms — that choice is becoming increasingly public.

The vaccines have been shown to be vigorously effective against severe illness and death after infection, including the highly contagious Delta variant, and public health officials, doctors and political leaders are urging inoculation. The Kaiser Family Foundation reported in late July that more than 90 percent of Covid-19 cases, hospitalizations and deaths have occurred among people who are unvaccinated or not yet fully vaccinated.

“The more people who are out there without the vaccine, the more Covid will spread,” said Luisa Borrell, distinguished professor at the CUNY Graduate School of Public Health & Health Policy.

A growing number of companies are mandating vaccines as a condition of employment, leaving unvaccinated workers at risk of being fired. CNN, which has required full vaccinations for all employees working in its offices and in the field, said on Thursday that it had fired three people who went into the office unvaccinated. Many others are adopting less sweeping — but perhaps more conspicuous — approaches, including mask mandates for unvaccinated workers or the requirement that they work remotely.

For employers, keeping workers safe while being equitable is one of the thorniest workplace challenges of the pandemic to date. In addition to potential legal ramifications if any of their policies are viewed as discriminatory, many companies are concerned that implementing separate protocols for unvaccinated workers could lead some of them to quit amid an already tight labor market. As of Aug. 5, roughly 39 percent of Americans ages 18 and over were not fully vaccinated, representing a large pool of people who could be in close contact with others at their jobs.

“If you’re going to treat vaccinated and unvaccinated employees differently, it needs to have a well-reasoned basis and not be done in a sort of harsh and derogatory way,” said Todd Logsdon, an employment attorney in Louisville, Ky., who is co-chairman of his firm’s workplace safety practice group. From a non-legal standpoint, he added, “the fact that you have some real morale issues — yeah, that employee is going to feel left out so you may have more turnover.”

But unvaccinated workers like Mr. Taranto fear that any company policy that identifies them is like a scarlet letter on their chests.

“My big comment to my boss is this is kind of like a big visual marker of the kind of belief I have,” Mr. Taranto said. “I don’t want this stuff broadcasted out to the world.”

Tension between the vaccinated and the unvaccinated has simmered since the shots became more widely available in the spring. But with the virus’s resurgence has come mounting frustration among vaccinated Americans toward the unvaccinated, making some unvaccinated workers especially circumspect about revealing themselves.

That is partly why some unvaccinated employees are so troubled by workplace policies that clearly distinguish them, though it seemed unlikely the protocols would change their minds about getting the shot.

Though her employer did not require her to be vaccinated, Ashley Williams, 25, said she felt her colleagues were crossing boundaries when they asked her if she was.

A licensed practical nurse in Bridgeport, Conn., Ms. Williams said she was constantly reading about vaccine development, but wasn’t confident enough in the information she gathered to get the shot. She said she believed that she would avoid getting infected by using personal protective equipment and hand sanitizer.

“Every time you tell someone you’re not vaccinated, people assume you’re a conspiracy theorist or you think the government is trying to poison you,” said Ms. Williams, who left her job at a mental health residential facility last month. “Now it’s a normal thing to go up to someone and ask if you’re vaccinated. This is personal information. Then there’s the judgment behind it.”

Without a federal vaccine policy, employers have largely been left to figure out guidelines themselves. They also must reckon with workers who have underlying health conditions and cannot receive the vaccine, and those with religious objections. The result is a patchwork of disparate policies for all workers to navigate.

And though the gap is shrinking, Black and Hispanic Americans have received a disproportionately smaller share of vaccinations, making it potentially more likely that protocols for unvaccinated workers would have a greater effect on people of color.

“Inclusivity — being equitable — has to be a consideration just given that so many companies have sort of loudly and proudly put on the table that they are going to focus on this in a way that they never have before,” said Tom Johnson, the chief executive of Abernathy MacGregor, a strategic communications firm that is working with companies on how to determine and communicate Covid safety guidelines.

Some companies, including Twitter and Salesforce, are requiring unvaccinated employees to work remotely. Others are asking unvaccinated workers to wear masks — often on the honors system.

Employees of Goldman Sachs, the global bank based in New York, are asked to report their vaccination status, which allows them to enter the building with their company ID card; the card won’t allow entry for those who have not done so, a company spokeswoman said. Unvaccinated workersmust undergo twice-weekly testing on site and wear a mask in the office.

For smaller firms, the issue can be a matter of staying in business at all. Pablo Lucanera, who owns a security guard business in Southern California’s Inland Empire, said he has been reluctant to mandate vaccines because he worries workers will leave for firms that don’t require them. Though he has asked workers’ vaccination status, he has not implemented separate policies for vaccinated and unvaccinated workers.

“We’ve taken the stance that we’re not going to ask employees to get vaccinated because of the sheer multiple who don’t want to get vaccinated,” said Mr. Lucanera, who is vaccinated. “If we demand for a lot of them to get vaccinated to come back to work, we are afraid they’re not going to come back.”

But as Covid cases have escalated, some of his unvaccinated workers have gotten sick. To cover their shifts, he has had to pay others overtime, which has been a drain on the company’s bottom line. Recently, he turned down a contract with a school district because he didn’t have enough officers to fulfill the request.

“It almost seems that whoever already doesn’t have it by this time has made up their minds,” Mr. Lucanera said. “If I put my foot down, will it hurt the company in terms of creating a bigger problem than we have?”

Still, for many unvaccinated workers, finding a new job is often not a desirable, or feasible, option.

Benjamin Rose, 28, who works at a global bank in the Chicago area, said his decision not to get the shot was “really just a cost-benefit analysis.” He contracted Covid-19 six months ago, he said, and a recent blood test showed he still had antibodies.

But because he is not vaccinated, his company requires that he work remotely even as it has begun to allow vaccinated employees back in the office. While he said he enjoyed the flexibility of remote work and was not opposed to vaccine mandates, he also did not want to feel like he was being coerced.

“I find it a little irksome how big corporations, the media and the government are all sort of this united front in pushing the vaccine so hard,” Mr. Rose said.

At the same time, he said, if his company instituted a vaccine mandate, he would likely comply.

“It’s not the hill I’m going to die on,” he said. “If it really became something that was going to strongly affect my career, I would probably just get it.”