The World Health Organization (WHO) has its eye a new Covid variant which seems to have a new symptom in children rarely caused by other Omicron sub variants. Dubbed as Arcturus, XBB.1.16 is fueling a new surge in many countries including US, Singapore, and Australia, among others.

The WHO declared XBB.1.16 a “variant under monitoring” in late March saying that it is the most transmissible variant yet. Maria Van Kerkhove, Covid technical lead for the WHO, said, XBB.1.16 variant is considered “one to watch” by the world health body.

Dr. Vipin Vashishtha—a pediatrician and former head of the Indian Academy of Pediatrics Committee on Immunization—said the symptoms of the variant include: high fever, cough and “itchy” conjunctivitis or pinkeye.

Richard Reithinger, an infectious disease epidemiologist at the RTI International, told Fortune that it is “probably too early to tell” if the virus’s symptom set has truly shifted. Conjunctivitis has previously been reported as a Covid symptom, he noted.

The XBB 1.16 variant is also known as Arcturus, a name that was made popular by Vipin M Vashishtha, former convenor of the Indian Academy of Paediatrics, who used it (as a hashtag) in a tweet on March 17 while warning about new COVID-19 cases.

“All eyes should be on India! If XBB.1.16 aka #Arcturus could succeed in wading through the ‘sturdy’ population immunity of Indians that successfully resisted the onslaught of variants like BA.2.75, BA.5, BQs, and XBB.1.5, then the whole world must be seriously worried!!” he said in another tweet.

The number of cases related to this variant is also rising in the US, Singapore, and Australia, among others.