The confirmation of the new coronavirus in a Montgomery County man who hadn’t recently traveled outside Texas marks the expected but challenging next phase in the Houston-region outbreak: community spread.

Public health officials Wednesday provided no information about how the patient might have acquired the virus but acknowledged that it must have been transmitted locally, not brought in from another area, like the other 13 cases in the region.

“We all knew that it was probably a matter of time before this was going to happen,” said Dr. David Persse, the city of Houston’s public health authority.

Persse called the case “the tip of the iceberg.”

Late Wednesday, city of Houston officials announced the city’s third confirmed case, a female between 15 and 25, who is self-quarantined in her home with mild symptoms. She apparently represents another travel-related case, having recently traveled to New York state.

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Community spread is important because it expands the number of patients health care providers have to consider when treating a respiratory illness characterized by fever. Previously, it was relatively easy to identify those with a risk factor, such as the 12 Houston-area patients who contracted the virus on a Nile River cruise and a woman who returned to Houston after living abroad in Italy. Now many of the patients seeking treatment will have no idea where they became infected.

“This opens up the possibility of patients coming in without a particular travel history or suspected contact with a recognized case,” said Dr. Robert Atmar, a professor of infectious diseases at Baylor College of Medicine. “It makes it more important that we have rapid testing that provides a quick turnaround.”

Such testing is in the process of coming to Houston, Atmar said, either through tests a hospital develops itself or private ones that began being rolled out to some hospitals this week. Last week, the Houston Health Department laboratory was verified to conduct coronavirus testing using a kit from the Centers for Disease Control and Prevention. But the city, which serves a 17-county area, has limited capacity and fairly stringent standards for the suspected cases it accepts.

The Montgomery man, who is in his 40s, is in fair but stable condition in a hospital in Montgomery County.

Public health officials announced Tuesday that he tested presumptively positive for COVID-19, the disease caused by the virus, but they didn’t disclose until Wednesday that he hadn’t traveled recently. And they noted he attended the Houston Livestock Show and Rodeo’s BBQ Cookoff event Feb. 28. Mayor Sylvester Turner announced Wednesday that the annual festival was being closed to prevent “community spread.”

The Houston tie to the case was disclosed Wednesday afternoon at Turner’s news conference. Montgomery County officials had informed Houston officials of the patient’s attendance at the cookoff Tuesday evening between 6 p.m. and 7 p.m., said Jason Millsap, chief of staff to County Judge Mark Keogh. That was not long before a packed crowd gathered for a K-pop concert featuring the group NCT 127.

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Montgomery County did not mention the patient’s visit to Houston during a morning news briefing because it was out of their jurisdiction, Millsap said.

The lack of disclosure was criticized by state Rep. Steve Toth, R-The Woodlands, who attended the briefing but didn’t learn of the patient’s time at the rodeo grounds until hours later on his drive back to Austin.

“I’m frustrated,” Toth said in a phone call. “I get the whole thing about wanting to make sure we don’t violate their (privacy rights), but I think the lack of frank reporting [from public officials] of honest information is going to cause more doubt when we speak later on what we know to be true.”

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Harris County public health officials have launched an investigation into who the man came into contact with while he attended the cookoff in Houston, and Montgomery County officials are monitoring his close contacts in the county’s northwest areas. All of them are under a 14-day quarantine.

Texas Health and Human Services officials said in a news release that the man had no out-of-state travel and no identified contact with another person with COVID-19. Officials are continuing to investigate whether it is definitely a case of community spread or if there’s still a chance it might be connected to another case.

The presumptive positive test still must be further confirmed by the CDC. Its lab is expected to conduct testing next week.

“From the very start, the state of Texas has anticipated the possibility of community spread of COVID-19, and the proactive strategies we have in place were developed with this very scenario in mind,” Gov. Gregg Abbott said in the release. “State personnel are trained and equipped to respond to this situation, and are actively working to mitigate the impact of community spread.”

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Also in the release, Texas Department of State Health Services Commissioner Dr. John Hellerstedt called on Texans to continue to take personal preventive actions like washing their hands, disinfecting homes and businesses and staying home if sick.

“With the possibility of spread in one of our communities, now is the time to intensify our efforts to stop the spread of COVID-19 in all our communities,” he said.

Hellerstedt also emphasized the importance to heed the advice of local leaders because there may be calls to take broader community actions.

Health officials said suspending large events, closing places where many people gather, and encouraging people to keep 6 feet of physical separation between them are recommended to slow the spread of the coronavirus.

Minimizing exposure is especially important for people who are 65 or older or who have an underlying health condition like heart disease, lung disease, diabetes, high blood pressure or cancer. People in those groups have a higher risk of developing severe diseases such as pneumonia if they get COVID-19. The safest thing for them during an outbreak will be to stay home as much as possible and minimize close contact with other people, city, county, state and federal health authorities have said. To get ready, they should talk to their doctor about getting additional prescription medications and have enough household items and groceries on hand to stay home as needed.

People who experience COVID-19 symptoms like fever, cough and shortness of breath should contact their health care provider and follow their instructions on being assessed, officials said.

To date, Texas has had 21 confirmed or presumptive cases of COVID-19. Texas Health and Human Services is posting the latest information, guidance for the public, health care providers and others, and updating case counts daily at www.dshs.texas.gov/coronavirus

todd.ackerman@chron.com

nicole.hensley@chron.com