MUMBAI, Sept. 10 -- Although the use of rapid antigen tests in Maharashtra began in July, the diagnostic tool already accounts for 31% of the total Covid-19 tests, with more than 60% of the daily tests in Maharashtra being carried out using the kits, according to the state health department data. RT-PCR test results come in eight hours, while antigen tests give results in 30 minutes and are considered less reliable. P4...