Acute Delta Hepatitis in Italy spanning three decades (1991–2019): Evidence for the effectiveness of the hepatitis B vaccination campaign

Updated incidence data of acute Delta virus hepatitis (HDV) are lacking worldwide. Our aim was to evaluate incidence of and risk factors for acute HDV in Italy after the introduction of the compulsory vaccination against hepatitis B virus (HBV) in 1991. Data were obtained from the National Surveillance System of acute viral hepatitis (SEIEVA). Independent predictors of HDV were assessed by logistic-regression analysis. The incidence of acute HDV per 1-million population declined from 3.2 cases in 1987 to 0.04 in 2019, parallel to that of acute HBV per 100,000 from 10.0 to 0.39 cases during the same period. The median age of cases increased from 27 years in the decade 1991-1999 to 44 years in the decade 2010-2019 (p < .001). Over the same period, the male/female ratio decreased from 3.8 to 2.1, the proportion of coinfections increased from 55% to 75% (p = .003) and that of HBsAg positive acute hepatitis tested for by IgM anti-HDV linearly decreased from 50.1% to 34.1% (p < .001). People born abroad accounted for 24.6% of cases in 2004-2010 and 32.1% in 2011-2019. In the period 2010-2019, risky sexual behaviour (O.R. 4.2; 95%CI: 1.4-12.8) was the sole independent predictor of acute HDV; conversely intravenous drug use was no longer associated (O.R. 1.25; 95%CI: 0.15-10.22) with this. In conclusion, HBV vaccination was an effective measure to control acute HDV. Intravenous drug use is no longer an efficient mode of HDV spread. Testing for IgM-anti HDV is a grey area requiring alert. Acute HDV in foreigners should be monitored in the years to come

Sylvatic rabies in the North Est of Italy: monitoring and evaluation of the effectiveness of prophylaxis in workers at risk and travelers

Rabies is a zoonotic viral encephalitis almost invariably fatal in both humans and animals. Rabies virus infects mammals through infected saliva via bites or scratches, although atypical exposures have been documented. In late 2008, wildlife rabies re emerged in Northeastern Italy. Since then, 287 animal cases have been documented with the last one diagnosed in a red fox in February 2011. No human cases have been reported linked to the recent epidemic and Italy has been declared as free from rabies in February 2013. Several oral fox vaccination campaigns and extensive monitoring of territories subject to the epidemic have been implemented together with education and preventive vaccination of workers at risk of viral exposure as forestry and wildlife workers, veterinarians, shelters \u2018operators and laboratory personnel. We have evaluated the level and persistence of serological response in workers at risk and travelers vaccinated following different immunization schedules. In 113 cases post exposure prophylaxis has been administered, five or four doses, with Rabipur (Novartis), Verorab (Sanofi Pasteur) vaccine. Serum samples from about 300 vaccinated volunteers at risk and travelers were collected from the Northeastern territories recently subject to the epidemic. All sera have been tested using an ELISA (Enzyme Linked Immunosorbent Assay) and a neutralising test, namely FAVN (Fluorescent Antibody Virus Neutralisation). The results of the ongoing analysis will be reported