HOUSTON : The US health watchdog has authorised the emergency use of a new and expensive saliva based laboratory diagnostic test for COVID-19 that could be a game changer in the diagnosis of the infection as it will enable rapid testing amongst more people easily.Stephen Hahn, the Food and Drugs Administration Commissioner, said the new saliva test would increase efficiency and avoid shortage of crucial test components like reagents.“Providing this type of flexibility for processing saliva samples to test for COVID-19 infection is groundbreaking in terms of efficiency and avoiding shortages of crucial test components like reagents," he said in a statement.The agency has previously authorised four other tests that use saliva for sampling,.