People wearing masks kiss each other at Milan Central Railway Station in Milan, capital city of Lombardy region, Italy, March 8, 2020. (Photo by Daniele Mascolo/Xinhua)

Deng Lingling (L) and Deng Junwei kiss while displaying their marriage certificates in front of the marriage registration office of the Civil Affairs Bureau of Nanshan District in Shenzhen, south China's Guangdong Province, Feb. 14, 2020. (Xinhua/Mao Siqian)

Cao Liyao (C), a female health worker on a team of 136 Beijing medical workers, kisses goodbye to her husband Wang Bin before leaving for Wuhan of Hubei Province to join the fight against the novel coronavirus epidemic, in Beijing, capital of China, Jan. 27, 2020. (Xinhua/Zhang Yuwei)

A newly-wed couple wearing face masks kiss each other during a wedding ceremony in Quezon City, the Philippines, on May 7, 2020. (Xinhua/Rouelle Umali)

Hao Tiedan kisses his son on his arrival at home in Taiyuan, north China's Shanxi Province, April 11, 2020. After 53-day work in Hubei and 14-day quarantine in Shanxi, Hao finally stepped on his way back home to reunite with his dear family who have been expecting and preparing for his return for days. (Xinhua/Cao Yang)

Li Peitao, a member of the medical team of Peking University Third Hospital supporting Hubei Province amid the coronavirus outbreak, kisses her daughter before attending a welcome ceremony in Beijing, capital of China, April 20, 2020. (Xinhua/Yin Gang)

A medical team member kisses her son before leaving for Hubei Province at Wusu International Airport in Taiyuan, north China's Shanxi Province, Feb. 20, 2020. (Photo by Chai Ting/Xinhua)

Little girl kisses the screen while chatting with her dad through video in Nanjing, east China's Jiangsu Province, Feb. 19, 2020. (Xinhua/Ji Chunpeng)