Frequency of infectious diseases in immigrants in a Western European country: a population-based study.

The aim of this population-based study was to assess the incidence rates of infectious diseases in native- (Italian) and foreign-born (immigrants) populations in a North Italy area, in 2006-2010. Crude, age-specific incidence rates (IRs) and age-standardised rate ratios (SRRs) between foreign- and native-born subjects and their 95% confidence intervals (95% CI) were estimated. A total of 32,554 cases of infectious diseases were found (9.9% in foreign-born subjects). The highest SRRs between foreign- and nativeborn subjects were found for tuberculosis (SRR = 27.1; 95% CI 21.3-34.3), malaria (SRR = 21.1; 14.6-30.4), scabies (SRR = 8.5; 7.6-9.4), AIDS (SRR = 2.5; 1.8-3.4) and viral hepatitis B (SRR = 3.3; 2.1-5.2). The highest IR was found for AIDS in people from the Americas (IR = 4.57; 95% CI 2.2-8.4), for malaria and tuberculosis in people from Africa (IR = 13.89; 11.6-16.5 and IR = 11.87; 9.8-14.3 respectively). Therefore immigrants are at a higher risk of acquiring some common infectious diseases compared to the native population in Western European countries.

Hepatitis B immune memory in children primed with hexavalent vaccines and given monovalent booster vaccines: an open-label, randomised, controlled, multicentre study.

BACKGROUND: In 2000, hexavac and infanrix hexa were licensed in Europe for primary immunisation of children against diphtheria, tetanus, pertussis, poliomyelitis, hepatitis B, and invasive infections caused by Haemophilus influenzae b. In 2005, hexavac was suspended because of concerns about the long-term immunogenicity of its hepatitis B component. We aimed to assess the duration of immunity and need for booster injections in children primed with these vaccines. METHODS: In an open-label, randomised, controlled, multicentre study in six local health units and at the Bambino Gesù Paediatric Research Hospital in Italy, antibody concentrations were measured 5 years after immunisation of infants with hexavac or infanrix hexa. Children with concentrations of antibodies to hepatitis B surface antigen (anti-HBs) lower than 10 mIU/mL were randomly assigned by simple randomisation to receive a booster of HBVaxPro or engerix B monovalent hepatitis B vaccine and tested 2 weeks later. Primary endpoints were the proportion of children with anti-HBs concentrations of at least 10 mIU/mL, geometric mean concentrations (GMCs) of antibody 5 years after vaccination, and the proportion of children with anti-HBs concentrations lower than 10 mIU/mL who had anamnestic response to booster. The study is registered with Agenzia Italiana del Farmaco, code FARM67NFPN. FINDINGS: 1543 children were enrolled, 833 had received hexavac and 710 infanrix hexa. 831 children who received hexavac and 709 who received infanrix hexa were included in the analysis. 319 children who received hexavac (38.4%, 95% CI 35.1-41.7) had anti-HBs concentrations of at least 10 mIU/mL compared with 590 who received infanrix hexa (83.2%, 80.5-86.0; p<0.0001). GMCs before booster were 4.5 mIU/mL in the hexavac group compared with 61.3 mIU/mL in the infanrix hexa group (p<0.0001). After booster 409 (92.1%, 89.6-94.6) of 444 children primed with hexavac and 99 (94.3%, 89.8-98.7) of 105 primed with infanrix hexa had anti-HBs concentrations of at least 10 mIU/mL (p=0.4); GMCs were 448.7 mIU/mL and 484.9 mIU/mL (p=0·6). The two booster vaccine groups did not differ in number of side-effects; no serious adverse events were reported. INTERPRETATION: 5 years after immunisation with hexavalent vaccines, immunological memory seems to persist in children with anti-HBs concentrations lower than 10 mIU/mL, suggesting that booster doses are not needed. Additional follow-up is needed. FUNDING: Agenzia Italiana del Farmaco.