House Republican leaders and doctors rallied for a news conference Thursday morning allegedly to urge Americans to get the coronavirus vaccine amid rising infections in the United States, but they used the event to attack Democrats, from whom they are said they had misrepresented the origins of the virus with no evidence.

The appearance of second- and third-tier Republicans in the House of Representatives, Reps Steve Scalise from Louisiana and Elise Stefanik from New York, along with a dozen doctors suggested that a resurgence in the spread of the virus fueled by the more contagious Delta variant was not had taken place called on the party to change its tone. Instead, Mr. Scalise and Ms. Stefanik beat up the Democrats for what they called a cover-up on behalf of the Chinese Communist Party.

Only at the urging of reporters did the leaders mention vaccinations.

“I would encourage people to get the vaccine,” said Mr. Scalise towards the end of the event, when his position pushed him to do so. “I have great confidence in that. I got it myself. “

He and other Republicans spent most of Thursday discussing unsubstantiated claims that the Chinese released a virulent, man-made virus in the world, accusing Democrats of ignoring it.

The event in front of the Capitol was planned as a “press conference to discuss the need for vaccinations for individuals, uncover the origins of the pandemic and keep schools and businesses open”. Yet the Republicans who attended, many of whom represent constituencies that have refused to get the vaccine, seem unable to bring themselves to stress the importance of the move.

Even the doctors who emphasized vaccinations, Rep. Andy Harris from Maryland and Senator Roger Marshall from Kansas, quieter and narrowed their statements.

“If you are at risk you should get this vaccine,” said Dr. Harris, adding, “We urge all Americans to speak to their doctors about the risks of Covid, speak to their doctors about the benefits of vaccination, and” then make a decision that is right for them. “

The Centers for Disease Control and Prevention recommend that everyone aged 12 and over – not just those at higher risk – get the coronavirus vaccine as soon as possible.

North Carolina Republican Rep. Greg Murphy countered, “This vaccine is a medicine and, like any other medicine, there are side effects and this is a personal choice.”

The emphasis on the so-called lab leak theory was surprising given the surge in infections that were concentrated in rural, heavily Republican regions of the country.

Nationally, the average of new coronavirus infections in 14 days is up 171 percent to more than 41,300 a day on Wednesday, and the death toll – a delayed figure – is up 42 percent from two weeks ago to nearly 250, so a New York time database. Still, new cases, hospital admissions and deaths remain at a fraction of their previous devastating highs.

Vaccines remain effective against the worst effects of Covid-19, including the Delta variant. Experts say that breakthrough infections are still relatively rare in vaccinated people. The delta variant accounts for an estimated 83 percent of new cases in the United States, the CDC said earlier this week.

The Kaiser Family Foundation reported in late June that 86 percent of Democrats had at least one shot, compared to 52 percent of Republicans. An April analysis by the Times found that the country’s least vaccinated counties had one thing in common: they voted for Mr Trump.

But dr. Murphy said the notion that conservatives are reluctant to get the vaccine “isn’t just insincere; It is a lie.”

As for the theory of the laboratory leak, the Republicans successively presented the issue as practically done: Research in a virus laboratory in Wuhan, China, created the novel coronavirus through risky experiments to “gain functionality” and then released it into the world.

“Criminals have been convicted on less evidence than is currently the case, and more evidence is being revealed every day,” said Iowa representative Mariannette Miller-Meeks.

Recently, some scientists have urged the possibility of a laboratory leak to be taken seriously, along with the possibility that the coronavirus emerged naturally, most likely from an animal. But they are mainly testing the possibility that a naturally developed virus was present in the laboratory and escaped, not that the virus was created on purpose. Even some of the most vocal scientific proponents of a laboratory leak do not claim that there is definitive evidence as to the origin of the virus.

Instead of covering up the matter, President Biden ordered U.S. intelligence services in late May to investigate the origins of the coronavirus and report back in 90 days.