San Francisco, Apr 19 (IANS): Executives at Google's Silicon Valley headquarters are discussing ways to protect themselves and their families from measles after one of them was found working at the office despite being infected by the highly contagious virus.

On Google's internal forums, employees expressed shock because they were not told sooner about their sick colleague who had been spending time in its Mountain View office building -- including a campus restaurant, BuzzFeed News reported on Thursday.

The employee was present in the office on April 4.

A select group of employees learned about the incident more than a week later, on April 13, when a company doctor emailed them about the infected the employee, the report said.

Later, however, the staff doctor sent a message to multiple internal groups at Google, reassuring a that they were safe while acknowledging that his communication had been "slow".

The reported case is part of a historic resurgence of measles in the US.

At least 555 people have been infected this year by the virus, which was declared eliminated in 2000, according to the Centres for Disease Control and Prevention (CDC).

Public health experts blame the uptick partially on the spread of anti-vaccine falsehoods on social media platforms, including Google's YouTube, which, under public pressure, recently removed ads from known anti-vaccine video channels, the report said.