The phenomenon has already been already established in Asia, with contagion fears leading to the cancellation of events on mainland China and in Hong Kong. Even outside the region, events such as the AAAI artificial intelligence conference in New York have seen a drop in delegate numbers from China, due to travel restrictions and risks.

But this week, two non-Chinese technology giants have pulled out of major European events, citing the same concerns. On Wednesday, South Korea’s LG said it would be staying away from the enormous Mobile World Congress (MWC) gathering in Barcelona at the end of this month. The next day, LG also pulled out of Integrated Systems Europe, an Amsterdam audiovisual trade show with over 80,000 attendees. And on Friday, Ericsson followed LG’s lead in dropping out of MWC.

“After an extensive internal risk assessment, Ericsson has decided to take further precautionary measures by withdrawing from MWC Barcelona 2020, the largest event in the telecom industry,” the Swedish telecoms firm said.

Ericsson said it appreciated the efforts made by MWC organizer and mobile industry body GSMA to control the risk—the GSMA announced a range of measures earlier this week, such as the heavy disinfection of surfaces. However, it continued: “As one of the largest exhibitors, Ericsson has thousands of visitors in its hall each day and even if the risk is low, the company cannot guarantee the health and safety of its employees and visitors.”

The GSMA responded with regret to Ericsson’s decision, noting that the cancellation “will have some impact on our presence at this time and will potentially have further impact.”

But the show must go on, the organization said, because—as is true, thanks to developments such as 5G—the telecoms industry is in the midst of upheaval. “It is of great importance to the GSMA to continue to convene the industry at this critical time where connectivity is on the cusp of a new industrial revolution,” the GSMA said.

As for whether conferences should be going ahead at all right now, LG seems to think not. In its Thursday statement about its withdrawal from Integrated Systems Europe, the company pointed to advice issued by the World Health Organization (WHO) last week, when the body upgraded the coronavirus outbreak to global health emergency status.

“With the WHO recommending that individuals ‘promote social distancing,’ LG management believes that the most responsible decision is to avoid participating in large public events until the situation stabilizes,” the company said.

Mike Blackman, the managing director of Integrated Systems Events, the company running the Amsterdam show, gave a very different interpretation of the WHO’s advice, telling Fortune it “really talks about when you’re meeting people who you believe may be sick.”

The WHO has recommended that everyone should “maintain at least 1 meter (3 feet) distance between yourself and other people, particularly those who are coughing, sneezing and have a fever.”

“There is no evidence at present to suggest that there is community spread in Europe, so WHO/Europe is not currently requesting that large gatherings are cancelled,” a WHO spokesperson said in a statement. “This type of issue is for national authorities to address, based on their assessment of the risk of holding the event in their country. Similarly, companies and other organizations are at liberty to make their own decisions according to their specific circumstances and their assessment of the risk to business. WHO works closely with organizations that plan mass gatherings to provide advice and support on any potential impact on health.”

Blackman said almost 50 Chinese companies, out of 250 that signed up to exhibit at the show, had withdrawn from Integrated Systems Europe because of Chinese travel restrictions. Three non-Chinese companies have pulled out—LG and two unnamed German and Japanese firms—all of which were worried about contagion.

Leading exhibition organizers met this week at a long-planned summit of UFI, the global association of the exhibition industry, in Rome. Blackman was there, and he said everyone was facing the same situation.

“Yes we are being affected [but] there is more effect from the rumor about the virus than the virus itself,” he said.

Indeed, on Friday the European Centre for Disease Prevention and Control said there were still just 29 confirmed coronavirus cases in the EU and U.K., and the risk of contagion in the region remained low.

But then again, Singaporean authorities reported Wednesday that several businesspeople—from Singapore, Malaysia and South Korea—came away from a conference there with a coronavirus infection. The question now is whether this reality does spread to European events, or whether such fears remain unfounded.

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