Editor's note: This story has been updated throughout.

Local health officials said Wednesday they did not know how a Houston-area man who tested positive for the new coronavirus this week became infected, suggesting the first signs of community spread of the virus within Texas.

“It could very likely be the first community spread,” said Alicia Williams, director of the Montgomery County Public Health District. If the virus is being transmitted from person to person in the general population, it is much harder to contain.

The case raises questions about the number of unknown infections in Texas, given that government testing capacity for the COVID-19 disease remains limited. The largest public health lab in Texas is able to conduct a maximum of just 26 tests per day. It's unclear how many tests a state network of 10 laboratories has conducted so far, but that figure is likely in the "dozens" as of Wednesday, Texas Department of State Health Services spokesman Chris Van Deusen said.

Local officials said they were taking the threat of community spread seriously, and Houston leaders announced Wednesday they were calling off the remainder of the weekslong rodeo event. Houston officials later said the man, who is in his 40s, attended a Feb. 28 barbecue at the city’s biggest annual event, the Houston Livestock Show and Rodeo. But it's unclear if he had symptoms at the time he attended.

Public health workers have been monitoring dozens of Montgomery County residents, officials said, and Montgomery Independent School District will cancel classes beginning Thursday, ahead of spring break.

Asked how the Montgomery County man might have contracted the virus, Melissa Miller said the case was still under investigation but that he had not traveled outside of Texas. “At this time, I don’t have an answer to that question,” Miller, the chief operating officer of the Montgomery County Hospital District, told reporters. “Anything is possible.”

Gerald Parker, associate dean for Global One Health at Texas A&M University, said confirmation of community spread would put Texas at an "inflection point."

"Things that we can do as individuals to avoid exposure and avoid exposing others is still just as important a message as it was yesterday," he said. "But it will also mean that we need to think more seriously about what are some of those social-distancing measures and community mitigation measures as well."

As of Wednesday afternoon, the tally of confirmed COVID-19 cases in Texas was 33. Eleven of those stem from people traveling abroad who were forced by the federal government to quarantine in San Antonio’s Lackland Air Force Base, where about 100 more people arrived to be quarantined Tuesday night. There have been other cases, linked to international and domestic travel, in the Houston area, the Dallas-Fort Worth area and the Longview area in East Texas.

The Montgomery County case was first reported Tuesday.

Lack of testing

Community spread in Texas will almost certainly increase the urgency around the availability of testing. State officials said they don't know how many tests have been issued in total so far. They're also fuzzy on how many tests the state should ideally have access to every day.

Gov. Greg Abbott told reporters March 5 that in the coming weeks, the state lab network would be able to handle more than 125 tests per day. Texas’ testing capacity is limited due to a shortage of testing materials and lab personnel, Van Deusen said.

Lack of testing is preventing officials from fully assessing the risks posed to Texans, said Dennis Perrotta, a retired Texas state epidemiologist.

“Clearly, the limited number of tests available at the current time is hindering our ability to understand what the epidemic looks like and where it’s moving,” Perrotta said. “That’s important from a public health perspective, and it’s also important to give our cities and companies and industries the information that they can make smart decisions about taking the appropriate precautions.”

But Van Deusen said he disagrees with the notion that the availability of tests is a problem.

"We have plenty of capacity in our state lab and the other public health labs at this point. Those labs have enough testing materials to meet demand," he said. "That capacity is expanding. CDC’s approval of testing both specimens from a single person together instantly doubles capacity across the entire system, and the federal government is in the process of approving new equipment that will let us process even more tests in a shorter period of time."

"There is not a shortage of available testing in the public health system," Van Deusen added.

On Tuesday, Texas Department of State Health Services Commissioner John Hellerstedt told state lawmakers that doctors and hospitals did not yet have access to testing on their own premises. For now, he said, public health labs are trying to stretch their available capacity by testing samples from people who appear most likely to have been exposed.

There are 10 public health labs in Texas that are operational or soon coming online to test nose and throat swabs for the presence of genetic material from the new strain of the coronavirus, known as SARS-CoV-2. (COVID-19 is the disease caused by the virus.) The U.S. Centers for Disease Control and Prevention has said that anyone can receive a test for the virus as long as a doctor agrees.

“As we progress, if we expect to see community-based spread of COVID-19, it will be useful to have wider availability of the testing,” Hellerstedt said. “I don’t know where they are with the development of point-of-care testing, but I think it’s still some months off.”

In an effort to keep up with the growing number of infected Americans, the U.S. Food and Drug Administration has given some private labs permission to develop their own tests.

Texas doctors can order tests from at least two private labs, LabCorp and Quest Diagnostics, Van Deusen said, adding that he could not speak to the cost of that testing to consumers, but DSHS is “not charging for tests we run in our lab.”

A LabCorp spokesperson said pricing for the test has not been finalized and declined to speculate on what the price will be. Quest Diagnostics expects to be able to perform tens of thousands of tests a week within the next six weeks, a spokesperson said. The lab has not yet finalized their uninsured patient price, but their "goal is to enable broad access," the Quest spokesperson added.

As more labs – both public and private – gain the ability to test for the virus that causes COVID-19, federal health officials have broadened the criteria for who may be tested.

Local leaders demand more testing

Still, local officials have said the availability of testing is insufficient. It's "very possible" that there are more people in the Houston region who are sick with COVID-19, Harris County Judge Lina Hidalgo said Wednesday.

"If we had the capability to test more people, we surely would be having more positives and perhaps more evidence of community transmission," she said.

But you do not have to test every person who is sick to deduce evidence of community spread, said Jessica Gullion, a former infectious disease epidemiologist and the associate dean of research at Texas Woman's University's College of Arts and Sciences.

"There's an assumption that every single person who's sick with a respiratory disease should be tested for corona. That's not really necessarily true," Gullion​​​​​​ said​. "If we know that somebody's been exposed, we may not have to test them because it's probably what they have."

The CDC has urged doctors to “use their judgment” when deciding if a patient merits testing and said they should consider symptoms as well as travel history and the possibility of close contact with people who tested positive.

Symptoms can include fever, cough and difficulty breathing, similar to seasonal flu. Doctors should rule out other causes of respiratory illness before ordering a coronavirus test, according to the CDC guidance.

On Tuesday, San Antonio Mayor Ron Nirenberg said the city "needs a heck of a lot more testing, and we’re requesting that ASAP."

In El Paso, Darlene Tarango, the laboratory manager for the city’s Department of Public Health, said Tuesday the city has the ability to test 400 people.

Mayor Dee Margo said the city can make a 24-hour request for additional test kits, if necessary. But because of shortages in other cities, there could be a need to test samples from outside El Paso.

"There is a possibility that we might be doing more testing, but not for El Pasoans," said Robert Resendes, the director of the city's health department. "If some of the other parts of Texas are running out of kits or they have too many cases, we are like a backup for them."

Julián Aguilar, Raga Justin and Emma Platoff contributed to this report.

Disclosure: Texas A&M University and the Texas Woman's University Board of Regents have been financial supporters of The Texas Tribune, a nonprofit, nonpartisan news organization that is funded in part by donations from members, foundations and corporate sponsors. Financial supporters play no role in the Tribune's journalism. Find a complete list of them here.