As the coronavirus spread across the globe last February, the World Health Organization urged people to avoid terms like the “Wuhan virus” or the “Chinese virus,” fearing it could spike a backlash against Asians.

President Donald Trump didn’t take the advice. On March 16, 2020, he first tweeted the phrase “Chinese virus.”

That single tweet, researchers later found, fueled exactly the kind of backlash the WHO had feared: It was followed by an avalanche of tweets using the hashtag #chinesevirus, among other anti-Asian phrases.

“The week before Trump’s tweet the dominant term [on Twitter] was #covid-19,” Yulin Hswen, an epidemiology professor at the University of California at San Francisco and a co-author of the study, told The Washington Post. “The week after his tweet, it was #chinesevirus.”

Hswen is among a group of researchers who analyzed hundreds of thousands of #covid-19 and #chinesevirus hashtags drafted the week before and after Trump first referred to the coronavirus as the “Chinese virus” on the social media platform.

Not only did more people use the #chinesevirus hashtag days after Trump’s tweet, but those who did were more likely to include other anti-Asian hashtags in their tweets, according to the peer-reviewed study published by the American Journal of Public Health on Thursday.

The group’s findings come amid a wave of racist attacks and threats against Asian Americans, which some advocates have blamed on Trump’s anti-China rhetoric over the pandemic. Trump repeatedly referred to the disease as the “Chinese virus” and the “Kung flu” during White House briefings, campaign rallies and other public appearances. Earlier this week, he once again called the disease the “China virus” in an interview with Fox News’s Maria Bartiromo.

The study also arrives days after eight people, including six Asian women, were shot dead in Atlanta-area spas. While the suspected gunman allegedly blamed a “sex addiction” for the rampage, authorities have not ruled out whether the killings were racially motivated.

Despite public health experts’ request that people refrain from attaching locations or ethnicity to the disease, Trump argued that the term “Chinese virus” was not discriminatory or racist because the virus “comes from China.”

Researchers, though, suspected they could demonstrate how his rhetoric inspired racist backlash against Asians.

“We wanted to provide evidence to show that the term ‘Chinese virus’ is associated with racist undertones,” Hswen said.

To test their theory, Hswen and other researchers analyzed nearly 700,000 tweets containing the hashtags #covid-19 and #chinesevirus published between March 9 and 23, 2020, corresponding to the week before and the week after Trump’s tweet. (All of the tweets analyzed were in English, and although most were published by U.S. users, the team did not set any geographic limitations when collecting the tweets.)

The group’s analysis found that the week after Trump first tweeted the phrase “Chinese virus,” the number of users tweeting the hashtag increased more than 10 times compared with before his post. Most who tweeted the phrase used it with a negative connotation and were more likely to display anti-Asian hate, the study found. Half the users who tweeted the #chinesevirus hashtag used other anti-Asian hashtags, while only 20 percent who used the #covid-19 hashtag did, according to the study.

“It perpetuated this idea that the disease was the fault of the Chinese,” Hswen told The Post. “It normalized these racist attitudes. That might have perpetuated these beliefs and behaviors offline.”

The findings did not surprise Russell Jeung, a professor of Asian American studies at San Francisco State University and co-founder of Stop AAPI Hate, which tracks incidents of hate and discrimination against Asian Americans and Pacific Islanders in the United States. Jeung argued that Trump’s repeated use of the phrase “Chinese virus” has a direct correlation with the rise in hate crimes.

“It demonstrates how words matter,” Jeung told The Post. “The term ‘Chinese virus’ racializes the disease so that it’s not simply biological but Chinese in nature, and stigmatizes the people so that Chinese are the disease carriers and the ones infecting others.”

Dean Winslow, a professor of medicine at Stanford University, said the study’s findings are consistent with what the public has continued seeing in the news: a rise of violence and harassment against Asian Americans. He wonders whether Americans would have used a geographical location to refer to the virus had it originated somewhere in the United States.

“It just happened that this particular virus may have arisen in China,” Winslow told The Post. “If this virus had arisen from a cave in New Mexico, I don’t think that people would be tweeting or calling it the ‘New Mexico virus.’ It’s not appropriate. This is science, and viruses don’t discriminate.”