News Scan: Health developments on Nov 17, 2021

A Mayo Clinic study published Nov. 16 found monoclonal antibody treatment was linked with a lower hospitalization rate among 1,395 breakthrough COVID-19 cases; U.S. and international agencies also reported an imported monkeypox case, an investigation of smallpox-labeled vials at a Pennsylvania lab, and an out-of-season flu increase in South Africa.

New research and public health reports were posted on Nov. 16–17, 2021. A Mayo Clinic retrospective study and several agency statements prompted renewed attention to respiratory and pox-related infections. The reports cover clinical findings, public health investigations, and regional surveillance results. Officials and researchers described follow-up actions and ongoing inquiries where relevant. Key reports: - Monoclonal antibody study: A Mayo Clinic retrospective study of 1,395 fully vaccinated patients with confirmed breakthrough COVID-19, published Nov. 16 in the Journal of Infectious Diseases, found treatment with single infusions of bamlanivimab, bamlanivimab-etesevimab, or casirivimab-imdevimab was associated with a 77% reduced risk of hospitalization; hospitalization was 2.7% with treatment versus 10.7% without treatment. - Patient details and variant context: The average age in the breakthrough cohort was 54 years, about 10% were cancer patients, and 69.8% had received the Pfizer–BioNTech vaccine a mean 120 days before infection; 71.8% of breakthroughs occurred after June 2021 during the Delta (B.1.617.2) surge, and authors noted casirivimab-imdevimab retained activity against that lineage in experimental data. - Imported monkeypox case: Maryland and the CDC confirmed a monkeypox infection in a resident recently returned from Nigeria; the patient has mild symptoms, is isolating and not hospitalized, and CDC said it is working with the airline and partners to reach possible contacts, noting the virus matches a strain re-emerging in Nigeria since 2017. - Smallpox-labeled vials found: Federal officials and law enforcement are investigating vials labeled "smallpox" discovered by a lab worker cleaning a freezer at a Pennsylvania vaccine research facility; the CDC reported no sign of exposure among staff and said it will provide more information as available. - Influenza activity abroad: South Africa's NICD issued an alert about an out-of-season rise in influenza activity that began in late August and increased in early November, with influenza B most commonly detected and clusters reported in schools and workplaces; the ECDC also reported rising flu detections in Europe with H3N2 dominant for the new season. Summary: The items together show both clinical findings and active public health monitoring: the Mayo Clinic study reported lower hospitalization rates among vaccinated patients treated with certain monoclonal antibodies, and agencies reported ongoing investigations or contact tracing for an imported monkeypox case and discovery of smallpox-labeled vials. Surveillance agencies in South Africa and Europe reported increased influenza activity and provided virus characterizations. Follow-up actions and investigations are ongoing and being reported by the respective health authorities.