The video posted on the Chinese mobile app Douyin (Tik Tok) and the article published by Liangshan News disproves the statement.
A video of a rainbow forming in the wake of a truck spraying moisture over a street has been shared on social media claiming that truck is disinfecting a street in China to control the novel coronavirus.
By reverse image search, the same video was found on the Chinese mobile app Douyin (Chinese version of the video-sharing app TikTok) with a caption that #Rainbow making machine.
As per the fact check done by the AFP, the Liangshan News, a local newspaper published an article on 21 March 2019 which shows a similar rainbow sighting photograph in its article. It had reported that in March, three additional dust control trucks were purchased. Every morning, afternoon and evening, a total of five dust control vehicles sprayed water on the main streets for dust control purposes, and it is also called 'aircraft artillery sprinkler'.
Therefore, the video showing a truck spraying in China's Sichuan province was for dust control purpose in March 2019, which was before the novel coronavirus outbreak.
The COVID-19 pandemic has given rise to a lot of potentially dangerous misinformation. For reliable advice on COVID-19 including symptoms, prevention and available treatment, please refer to the World Health Organisation or your national healthcare authority.