(AP) — COVID-19 cases are rising again as a new variant begins to circulate in some parts of the world. The World Health Organization said Wednesday the rise in cases is primarily in the eastern Mediterranean, Southeast Asia and western Pacific regions.

Airport screening in the United States has detected the new variant in travelers arriving from those regions to destinations in California, Washington state, Virginia and New York.

The new variant is called NB.1.8.1. It arrives as the United States’ official stance on COVID-19 vaccination is changing. On Tuesday, Health Secretary Robert F. Kennedy Jr. announced that COVID-19 shots are no longer recommended for healthy children and pregnant women — a move immediately questioned by several public health experts.

The new variant, increasing globally, had by mid-May reached nearly 11% of sequenced samples reported. The WHO has designated it a “variant under monitoring” and considers the public health risk low at the global level with current vaccines expected to remain effective.