In an apparent effort to pre-empt a norovirus outbreak like the one that sickened more than 150 people in Boston a few months ago, Chipotle has temporarily closed a restaurant in the nearby town of Billerica after a worker there was diagnosed with the virus.

TV news reports out of Boston say that no customers have turned up ill and that the temporary shutdown is a voluntary measure on the part of Chipotle.

In the wake of the earlier norovirus incident, along with a recent 9-state E. coli outbreak, Chipotle made policy changes intended to reduce the odds of future problems.

In addition to new food safety protocols — like having raw veggies chopped at a central kitchen, dipping onions in boiling water, and marinating raw chicken in sealed bags — the burrito chain decided to give employees sick leave, and said that restaurants will be temporarily shut down for cleaning after anyone vomits inside the building.

[via WCVB.com and WHDH.com]