A measles outbreak that surfaced among crew members working aboard a cruise ship docked in Italy last week prompted a risk assessment and mitigation steps yesterday from the European Centre for Disease Prevention and Control (ECDC).
Italian health officials reported the outbreak on Feb 28, the day after the cruise ship arrived in Civitavecchia from Palma de Mallorca, Spain, the ECDC said in its report. About 40 crew members had suspected infections, and a few days earlier a crew member had left the ship at another Italian port with a respiratory illness and a skin rash.
Nine of the workers were hospitalized in Rome, and lab tests confirmed measles in seven of them, according to the report. After the ship continued its voyage, probable infections were reported in two more crew members on Mar 1, and they and their close contacts were transferred to a resort for isolation.
No new suspected cases have been identified since then, and health officials have assessed sanitary conditions on the vessel. As of yesterday, all suspected cases were in crew members, with none in passengers.
The ECDC said the ship regularly sails on 7-day cruises in the western Mediterranean and had recently visited port cities in France, Spain, and Italy. It added that that the apparently high attack rate among crew hints at low vaccination coverage in the group.
The agency spelled out suggested response steps for passengers and crew who sailed with the sick workers and those who will be taking a cruise on the ship.
Norovirus outbreaks aren't unusual on cruise ships, but measles outbreaks are relatively rare, and measles is known as one of the most contagious infectious diseases.
The US Centers for Disease Control and Prevention (CDC) in its background information on cruise ship health says crew members and travelers often come from countries where vaccination is not routine, and outbreaks of chicken pox and rubella have been reported on cruise ships.
Mar 5 ECDC rapid risk assessment