Starbucks is temporarily restricting the use of reusable, personal mugs in stores because of the coronavirus, the company announced Wednesday.

In an open letter posted on the company's website, executive Vice President Rossann Williams wrote that the company has "taken a series of precautionary steps in response to this emerging public health impact."

In January, Starbucks closed half of its China stores because of the outbreak, though many have since reopened, officials have said.

"Our focus remains on two key priorities: Caring for the health and well-being of our partners and customers and playing a constructive role in supporting local health officials and government leaders as they work to contain the virus," Williams said in Wednesday's letter.

In her letter, Williams outlined five of the company's steps, which include "increased cleaning and sanitizing for all company-operated stores to help prevent the spread of all germs" and restricting "all business-related air travel, domestic and international through March 31." 

The company also is "pausing the use of personal cups and 'for here' ware in our store," Williams said, noting they will still honor "the 10-cent discount for anyone who brings in a personal cup or asks for 'for here' ware."

As part of the steps, Starbucks converted its annual shareholders meeting in hometown Seattle to a virtual-only event due to concerns about the virus. The meeting will be March 18, as originally planned.

The partylike event that attracted 4,000 shareholders last year was supposed to be held at a theater in downtown Seattle. A virus cluster has emerged in Washington state, however, with 10 reported deaths.

"We will continue to stay close to our partners and local health officials, and we are optimistic this will be a temporary situation," Williams said.

Contributing: Associated Press