South African scientists discovered a new and possibly more contagious coronavirus variant, resulting in countries closing their doors for travel again. The World Health Organization (WHO) listed the Omicron variant as a new strain of concern on Friday, November 26. Advisers are currently monitoring the situation. Scientists emphasize that there is not enough information on Omicron, such as if the variant is indeed more contagious, if it results in more severe infection, and what effect it might have on vaccination effectiveness. Dr. Francis Collins, head of the National Institutes of Health, says that the Omicron strain was particularly infectious in South Africa, but this does not mean the virus would spread abroad. However, former co-chair of the South African Ministerial Advisory Committee on COVID-19 Salim Abdool Karim explains that Omicron contains identical changes to the Delta variant and is expected to spread more quickly. Karim added in a statement that more information may be available in a few weeks.