Measles outbreak in a public hospital, Szczecin, Poland, January 2019

Abstract

Abstract Background In January 2019, a measles infection in an employee in a 168-bed hospital was reported to the local sanitary station (PSSE) in Szczecin, Poland. Further transmission occurred in the hospital and more cases were reported in the community. We investigated to identify transmission routes and implement control measures. Methods An outbreak case was any hospital staff, visitor, or patient, or any person in contact with them, meeting clinical criteria, from 3rd January. Cases were interviewed by PSSE to identify contacts and verify vaccination status. Susceptible contacts were offered post exposure vaccination (PEV). Clinical specimens were sent to the National Reference Laboratory for RT-PCR and serology confirmation. We collected vaccination status, geographical location and queried hospital authorities about control measures. Results The index case, the hospital employee, returned from Ukraine one day before onset of symptoms. We identified 17 (8 confirmed, 7 probable, 2 suspect) outbreak cases including 11 hospital personnel. Four of the personnel provided vaccine documentation (36%), of which three had received 2 doses. Contacts identified as susceptible (130) received PEV. Eight cases were contacts of the index case but were not promptly identified and did not receive PEV. The hospital refused new admissions for 19 days. Another 16 cases were identified in the community, with exposure information not sufficient to establish an epidemiologic link with the outbreak. Conclusions The introduction of measles into a susceptible population and missing contacts for PEV led to a hospital-associated outbreak. For the community cases, exposure may have occurred in multiple public spaces around the hospital. Most of the hospital staff who developed measles lacked vaccination records. The PSSE has recommended MMR vaccination for all hospital personnel without such documentation. Key messages This study shows how a single imported case, in an environment poorly immunized could lead to an outbreak and potentially transmit it to the community. It is very important to keep a high rate of measles vaccination (95% recommended by WHO) in the community and insure of immunization status of health workers.