FULLERTON, Calif. >> The post-Thanksgiving rush for coronavirus testing is on: Pharmacies in the Southern California suburbs are advising customers lucky enough to score appointments that it could be four days before they receive results. In Chelsea, Massachusetts, a line of people who hoped for testing, pelted by rain and wind, strung along an entire block early this week. In Atlanta, people have idled in cars, sometimes for hours, to get swabbed at drive-thrus.

Testing has long been one of the keys to controlling the spread of a virus that with the onset of winter is entering its most dangerous phase. Yet even as cases per capita have rocketed, securing a test has become enough of an ordeal that many people have been dissuaded from even trying.

That has begun to change in recent weeks as a handful of communities across the country have rolled out the first do-it-yourself home saliva tests, which require users to simply dribble into a test tube, seal it and send it to a lab. As the tests become widespread, they could provide a less-uncomfortable alternative to nasal swabs and enable more people to safely return to work and school in the months before a vaccine is widely available.

In California, Orange County, home to Disneyland and Surf City, last week kicked off an ambitious effort to distribute 500,000 home-use saliva test kits to its 3.4 million residents by the end of December. Its initial push has focused on Anaheim and Santa Ana, the two most populous cities where the pandemic has taken an outsize toll on the Latino and immigrant populations.

Among those who stopped by to collect kits outside the Family Health Matters clinic was Sandra Reyes-Aceves, 48, who lives with her two teenage children and aging parents in Anaheim.

“This is the best thing for my parents’ safety. I don’t have to make them leave the house to get tested,” Reyes-Aceves said. Although no one in her family has symptoms, she said, she worries that she or the children could have the virus and not know it.

Public health officials have long hoped that combining the ease of saliva sampling with at-home collection would open important new windows into the spread of the virus and help persuade those who did not know they were infected to stay home and limit further transmission.

“The big issue is, how do you get more people to get tested?” said Anne Rimoin, a professor of epidemiology at the UCLA Fielding School of Public Health. “Everyone has seen lines looping around stadiums and urgent cares.”

A test people can do at home and mail in “really helps,” she said. “It isn’t going to end the pandemic, but it is certainly a major step toward making testing more accessible and widespread.”

Minnesota, now with one of the highest rates of new cases in the country, became the first state, in early November, to offer at-home COVID-19 saliva testing for all residents, whether they have symptoms or not.

Once a testing kit is ordered, it is typically shipped within 24 hours. During sample collection, users are supervised via Zoom by a health worker at Vault Health, the company contracted by Minnesota’s health department to manage the tests. Results are available in 24 to 48 hours.

“With community spread at such high levels, we’ve focused on removing barriers to make testing as easy and accessible as possible,” said Dan Huff, assistant commissioner for health protection at the Minnesota health department.

Thus far, 261,000 kits manufactured by Infinity BiologiX, the first home saliva test to secure emergency use authorization from the federal Food and Drug Administration, have been distributed statewide.

The decision to make home saliva tests available came as infection rates in Minnesota climbed to new highs. State health officials said it was too early to ascertain whether the availability of new testing was helping to contain the virus because it was still so new. In fact, for the time being, the tests are likely to lead to higher case numbers.

Kristine Grover of Blackduck, Minnesota, said that she decided to order the home test after her 12-year-old son, Keaton, came down with a fever, cough and runny nose.

“We knew he would tolerate the saliva test better than the nasal swab,” she said. “I ordered the test on a Monday, he performed the test on Tuesday, and we received the negative results on Thursday morning.”

A well-designed saliva test can be as accurate as a nasal swab test, scientists say. Researchers have found significant levels of the coronavirus in oral secretions. Like nasal swab tests, saliva tests are based on polymerase chain reaction technology, which amplifies small amounts of viral material for analysis.

Sports leagues, schools and colleges were among the early adopters of saliva tests, and newly developed tests have been hitting the market after winning FDA approval. Whether they could supplant nasal swab tests depends, in part, on how quickly labs can ramp up production.

In St. Louis, the medical school of Washington University began offering a saliva test to some local teachers this week. In Greenwich, Connecticut, the Greenwich Academy, an all-girls private school, credits the use of regular use of spit tests for allowing it to stay open.

As home test kits become more widely available, their success in mitigating the spread of the coronavirus could hinge on how often they are used.

“What is necessary is for people to test frequently,” said Jerry Cangelosi, an infectious diseases expert at the University of Washington in Seattle. “Home testing is effective if it can be done repeatedly, such as weekly, not once a year.”

In New Jersey, Burlington County suspended its home-testing program after many people took kits and failed to use them. Of the more than 2,400 saliva kits requested by residents and paid for by the county since October, only 900 have been mailed into the lab.

“Unfortunately, numerous people have requested the test kits but failed to return them with collected samples for testing, essentially keeping the kits until they decide they need them,” Herb Conaway, the county’s health director, said in a statement. “This is not how the program was intended to work.”

In California, where a new, ominous wave of the coronavirus pandemic has led to a record surge in cases, widespread testing could be crucial.

While upscale coastal cities, like Newport Beach, have had relatively few cases, inland cities, like Santa Ana and Anaheim, account for a disproportionately high share of infections, hospitalizations and deaths, and the initial at-home tests are being targeted there.

“The inability of some residents who lack means to work remotely or quarantine appropriately has led to a disparity in infection rates between communities,” said Andrew Do, vice chair of the county’s board of supervisors. “Our challenge will be to get the message out: This is how you protect loved ones, and we’ll be able to go back to businesses and interacting with each other.”

Unlike Orange County’s nose swab testing program, which has targeted people with coronavirus symptoms, the in-home saliva effort is intended to widen testing to include people who might not be suffering from any symptoms.

In the initial phase, the county has partnered with five community clinics to distribute 11,000 testing kits. The test was developed by Ambry Genetics, a local company with expertise in genetic diseases that has converted part of its lab to produce the tests.

“Our test is, literally, you spit up to a point in the tube, seal the cap and mail it in,” said Aaron Elliott, the company’s chief executive officer, who compared it to consumer genetics tests like those from AncestryDNA. “It’s much easier than tickling your brain with a nasal swab.”

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