COVID-19 exposed how quickly a respiratory outbreak can trap crew in place, close crew changes, and overwhelm shipboard medical resources. Pandemic preparedness is now a standing MLC 4.1 + ISM Code 7 topic — every operator should have a documented pandemic-response annex to the SMS covering PPE stock, isolation cabins, ventilation control, and stakeholder communications.
MLC 2006 Regulation 4.1 (medical care onboard + ashore), ISM Code Element 7 (development of plans for shipboard operations), WHO IHR 2005 (International Health Regulations), IMO MSC-MEPC.7/Circ.11 COVID-19-related crew-change guidance (extended for general pandemic preparedness).
Disclaimer. General information only — flag-state and port-state pandemic-response requirements vary. Consult your DPA, P&I club, and flag-state administration for the current operational advisory.