A major hospital near the Portuguese capital will implement a two-week closure of multiple children’s wards after a doctor there tested positive for the Covid-19 Omicron variant, with dozens now in quarantine amid a new outbreak.

The Garcia de Orta hospital in Almada, located some 12 kilometers (7 miles) south of Lisbon, said it would temporarily shut down its pediatric emergency and outpatient departments on Tuesday night, citing a single Omicron infection among staff, according to a statement obtained by Reuters. The wards will remain closed for 14 days.

The hospital noted that 28 people believed to have interacted with the infected doctor are now in isolation, while another 69 people across Portugal are currently in quarantine after coming into contact with other suspected Omicron carriers, bringing the total to 97, according to local media reports.

The Garcia de Orta doctor who tested positive on Tuesday also serves on the medical staff of a top division football club, Belenenses SAD. In addition to the doctor, 12 other Omicron cases have been detected among the team as of Monday, health authorities said. At least one athlete on the team recently returned from South Africa, where some of the first Omicron infections were detected earlier this month.

The World Health Organization (WHO) designated the new “variant of concern” last week, with its chief scientist Soumya Swaminathan noting that Omicron was seen to have a large number of mutations in its spike protein, the mechanism by which the coronavirus hijacks host cells and causes infection. However, while Omicron has already triggered alarm around the world, prompting travel bans and other restrictions in a growing number of countries, it remains unclear if the new strain is more infectious or deadly than others seen before it. The WHO has suggested it could take several weeks before much insight is gleaned into the variant, as researchers race to determine whether it is resistant to existing Covid-19 vaccines or therapies.

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