Washington, Aug 27 : The US Centers for Disease Control and Prevention (CDC) has changed its Covid-19 testing guidelines, which no longer recommends testing for most people without symptoms. The new guidelines, updated earlier this week, asks people to get tested if they have coronavirus symptoms or have had close contact (within 6 feet of an infected person for at least 15 minutes), or have been asked or referred to get testing by their healthcare provider, local or state health department, reports Xinhua news agency. "Not everyone needs to be tested," said the new guidelines. Previously, the CDC said viral testing was appropriate for people with recent or suspected exposure, even if they were asymptomatic. The updated guidelines prompted concerns from some doctors and experts, who warned asymptomatic carriers play a major role in spreading Covid-19. Testing and isolating those silent emitters are vital to containing the spread of the pandemic, experts said. The US currently accounts for the world's highest number of cases and deaths at 5,821,195 and 179,708 respectively. /IANS