FILE PHOTO: A visitor uses a mobile phone in front of the Cisco booth at the Mobile World Congress in Barcelona, Spain, February 26, 2019. REUTERS/Rafael Marchante

(Reuters) - Cisco Systems Inc’s video-conferencing app Webex registered a record 324 million attendees in March, with usage more than doubling in the Americas, as the coronavirus-led lockdowns forced businesses to have employees work from home.

Webex and rival meeting platforms from Zoom and Microsoft Corp’s Teams are being used worldwide to host everything from virtual classrooms and business meetings to church services, as people stay at home to restrict the spread of the pandemic.

Zoom's daily users ballooned to more than 200 million in March from a previous maximum total of 10 million, the company said here on Wednesday. It was, however, not clear if the number was comparable with Cisco's due to the different ways the companies calculate meeting attendees.

“Webex grew 2.5 times in Americas, four times in Europe and 3.5 times in Asia Pacific. Our growth is sourced from enterprise expansion, education and telehealth,” said Sri Srinivasan, senior vice president and general manager, Cisco Collaboration.

About 73 million meetings took place in March and well over 22 million meetings per week in the last two weeks, Sri Srinivasan added.

Cisco said the latest user numbers have more than doubled since January.

The explosion in demand has spurred a huge boom for what were often relatively small businesses while raising issues of privacy and abuse.

Zoom’s share price has surged five-fold in value since going public in April last year, but the company has faced a backlash in the past week from users worried about the lack of full encryption of sessions and zoombombing, where uninvited guests crash meetings.

Cisco said its Webex system, which includes teleconferencing and is older, was fully encrypted.