June 28 (Reuters) - Los Angeles County health officials have recommended that all residents wear masks in public indoor spaces irrespective of whether they have been vaccinated or not for COVID-19 due to the increased circulation of the highly transmissible Delta variant.

Monday's announcement of the recommendation by the health department in the country's most populous county comes as the U.S. Centers for Disease Control and Prevention (CDC) noted that Delta variants are now responsible for about one in every five new infections across the country.

Despite the latest recommendation, LA County health officials noted that "fully vaccinated people appear to be well protected from infections with Delta variants."

"Public Health strongly recommends people wear masks indoors in settings such as grocery or retail stores; theaters and family entertainment centers, and workplaces when you don't know everyone's vaccination status," the county's health department said.

Till date, the department has identified 1,249,560 positive cases of COVID-19 across all areas of LA County and a total of 24,480 deaths, it said.

The Delta variant was first detected in India and is now circulating widely in many countries. It could quickly become the dominant version of the virus in the United States, CDC Director Rochelle Walensky has warned.

Cases of COVID-19 and the more contagious Delta variant are rising in some parts of the United States, particularly where vaccination rates are low.

(Reporting by Kanishka Singh in Bengaluru; Editing by Stephen Coates)