Three U.S. universities have announced a reinstatement of masks on campuses, citing increasing COVID-19 cases among students. At Georgetown University in Washington, D.C., an indoor mask requirement began on April 7 and is applicable on the main and medical center campuses. The decision was taken after undergraduate students exhibited higher rates of infection. The rules apply in all circumstances except when students are at a private office or personal residence or are eating and drinking. “This increase is partly due to the impact of the BA.2 Omicron subvariant. BA.2 is now the dominant strain in the United States, including in D.C. and on our campuses. While recent studies show that BA.2 does not cause more severe illness than the initial Omicron variant, they also show that BA.2 is even more transmissible,” the university said in a notice. In addition, Georgetown also “strongly” recommended community members to wear a mask when …