Seroprevalence of vaccine-preventable and non-vaccine-preventable infections in migrants in Spain

BACKGROUND: Updated seroprevalence studies of infections in migrants may aid the design of tailored vaccination and prevention programmes. The objective of this study was to describe the seroprevalence rates for potentially transmissible viral infections in migrants attended at a referral centre in a major European city. METHODS: Descriptive analysis of seroprevalence of vaccine-preventable and non-vaccine-preventable infections in migrants attended at a centre in Madrid, Spain (2018-19). Recorded variables included age, gender, country of birth/continent of origin, time from arrival to Spain until first clinic visit, rubella, measles, mumps, varicella (VZV), hepatitis B virus (HBV), hepatitis A virus (HAV), hepatitis C virus (HCV) and HIV serology. RESULTS: In total, 468 patients were included, 135 females (28.8%) and 333 males (71.2%), mean age 30.4 years. The majority of patients were from Africa (52.5%, of which 88.2% from sub-Saharan Africa), followed by Latin America (38.5%) and other areas (9%). Seroprevalence for tested migrants for rubella, measles and mumps was 20 years (compared with those ≤ 20 years). Over 10% of females were potentially susceptible (negative/indeterminate serology) to rubella (11.4%), measles (12.7%) or mumps (10.3%). Lowest rates of rubella seropositivity were in Latin American migrants (over 12% potentially susceptible); measles and mumps seropositivity was lowest in migrants from areas other than Africa/Latin America (74% and 68%, respectively). Seroprevalence rates were 91% for VZV, 90% overall for HAV, ~6% for HBV chronic infection (~50% of migrants tested susceptible), 2% for HCV and 6% for HIV. CONCLUSIONS: Differences in seroprevalence for vaccine-preventable and transmissible infections according to gender, age range and area of origin were observed. Tailored screening, vaccination and prevention strategies in potentially vulnerable migrant groups should be designed.