"Blanket travel bans will not prevent the international spread, and they place a heavy burden on lives and livelihoods," the organization said. "Countries should continue to apply an evidence-informed and risk-based approach when implementing travel measures in accordance with the IHR [International Health Regulations]."
In addition, full travel bans "can adversely impact global health efforts during a pandemic by disincentivizing countries to report and share epidemiological and sequencing data," the WHO said.
Among advisable measures, the World Health Organization named "screening of passengers prior to travelling and/or upon arrival," including via the use of SARS-CoV-2 testing or the application of quarantine to international travelers. These measures, nonetheless, need to be "defined following a thorough risk assessment process." They also should be commensurate with the risk, time-limited and applied "with respect to travelers’ dignity, human rights and fundamental freedoms."
All countries should ensure that the measures are regularly reviewed and updated when new evidence becomes available on the epidemiological and clinical characteristics of Omicron or any other variant of concern (VOC). Any travel-related risk mitigation measures should be part of an "overall national response strategy" regarding VOC.
According to the WHO, as of November 28, 2021, 56 countries were reportedly implementing travel measures aimed at "potentially delaying the importation of the new variant."
Last Friday, the World Health Organization (WHO) designated the B.1.1.529 variant as a "Variant of Concern" (VOC) and assigned it the Greek letter Omicron. It also said that the new variant has "a large number of mutations, some of which are concerning." "Preliminary evidence suggests an increased risk of reinfection with this variant, as compared to other VOCs," it said.