Business review platform Yelp announced Thursday it is adding COVID-19 guidelines to its business listings, allowing users to filter companies based on vaccination requirements.

The platform said in a blog post that users will be allowed to filter businesses based on whether they require proof of vaccination and whether staff are fully vaccinated.

The company further said it will be monitoring Yelp pages of businesses that activate these attributes for any backlash they receive.

The move comes as businesses and some state and local governments impose stricter vaccine mandates amid an increase in coronavirus infections fueled by the delta variant.

Yelp said that in recent weeks it has seen a rise in “review bombing,” when businesses get a flurry of comments based on people’s opinions about the pandemic rather than their customer experiences.

The company has placed 100 “Unusual Activity Alerts” on pages where such instances have occurred, leading to the removal of nearly 4,500 reviews from the platform.

Yelp said its team of investigators may investigate if an “unusual spike in traffic” on a business’s page is detected. The company may temporarily disable the ability to post on that business’s page as it places an alert over the reviews.

Once the activity has stopped or decreased dramatically, it will then “clean up” the page so that only firsthand customer experiences are reflected.