Solar radiation drives methane emissions from the shoots of Scots pine.

Plants are recognized as sources of aerobically produced methane (CH4 ), but the seasonality, environmental drivers and significance of CH4 emissions from the canopies of evergreen boreal trees remain poorly understood. We measured the CH4 fluxes from the shoots of Pinus sylvestris (Scots pine) and Picea abies (Norway spruce) saplings in a static, non-steady-state chamber setup to investigate if the shoots of boreal conifers are a source of CH4 during spring. We found that the shoots of Scots pine emitted CH4 and these emissions correlated with the photosynthetically active radiation. For Norway spruce, the evidence for CH4 emissions from the shoots was inconclusive. Our study shows that the canopies of evergreen boreal trees are a potential source of CH4 in the spring and that these emissions are driven by a temperature-by-light interaction effect of solar radiation either directly or indirectly through its effects on tree physiological processes.

Hepatitis E in Italy: 5 years of national epidemiological, virological and environmental surveillance, 2012 to 2016.

Increasing numbers of hepatitis E cases are being reported in several European countries, including Italy, but the burden of hepatitis E virus (HEV) infection is largely unknown in the latter. To gain a better understanding of HEV epidemiology at national level in Italy, we piloted a strengthened and integrated human (epidemiological and virological) and environmental HEV surveillance system between 2012 and 2016. Over the 5-year period, 169 confirmed hepatitis E cases were identified, with a national annual incidence of 0.72 cases per 1,000,000. Of 65 HEV-RNA positive samples of sufficient quality for molecular analysis, 66% were genotype HEV3, 32% HEV1 and 1% HEV4. The most frequent risk factor reported by all HEV3 infected cases, was the consumption of undercooked pork and sausage. For the environmental surveillance, 679 urban sewage samples were collected from 53 wastewater treatment plants and HEV-RNA was detected in 38/679 of the samples. Among these, 25 (66%) were genotype HEV3 and the remaining were HEV1. We demonstrate that autochthonous transmission and environmental circulation of genotype HEV3 is adding to travel-related HEV transmission in Italy. We recommend the 'One Health' approach to integrated surveillance, and to include HEV-related messages within health information campaigns focussing on food security.

Acute Hepatitis B After the Implementation of Universal Vaccination in Italy: Results From 22 Years of Surveillance (1993-2014).

BACKGROUND: Hepatitis B vaccination has proven to be very safe and highly effective. This study assessed the proportion of successfully vaccinated individuals among cases with acute hepatitis B, the proportion of preventable cases if individuals were vaccinated as recommended, and the reasons for failures. METHODS: We analyzed data reported to the Italian Surveillance System for Acute Viral Hepatitis from 1993 to 2014. RESULTS: A total of 362 of 11 311 (3.2%) cases with acute hepatitis B were vaccinated. Of the 277 cases for whom immunization data were available, 50 (18%) received a complete vaccination course according to the correct schedule and before exposure to hepatitis B virus. Molecular characterization of 17 of these cases showed that 6 were infected with S-gene mutants. Among the 10 949 unvaccinated cases, 213 (1.9%) escaped mandatory vaccination and 2821 (25.8%) were not vaccinated despite being at increased risk of infection. Among the latter, the most common risk factors were cohabitation with hepatitis B surface antigen (HBsAg) carriers, intravenous drug use, and homosexual/bisexual practices. Thirty-seven percent of the unvaccinated households with HBsAg carriers were aware of their risk. Lack of trust in the vaccination, negative attitude, and inaccurate beliefs followed by lack of or poor communication and low perceived severity of the disease were the most frequent reasons for vaccine hesitancy. CONCLUSIONS: Development of acute disease in successfully vaccinated individuals is a rare event. Further efforts are needed to enhance the vaccine coverage rate in individuals at increased risk of infection.

Clinical, epidemiological and virological features of acute hepatitis B in Italy.

PURPOSE: To evaluate the association of hepatitis B virus (HBV) genotypes, basal core promoter (BCP)/precore (PC) and S gene mutations with the clinical-epidemiological characteristics of acute hepatitis B (AHB) in Italy. METHODS: During July 2005-January 2007, 103 symptomatic AHB patients were enrolled and prospectively followed up at 15 national hospitals. HBV genotypes, BCP/PC and S gene variants were determined by nested-PCR and direct sequence analysis. RESULTS: Genotype D, A and F were detected in 49, 45 and 6% of patients, respectively. BCP, PC, and BCP plus PC variants were found in 3.1, 11.3 and 7.2% of patients, respectively. At enrollment, 68.3% of patients were hepatitis B e antigen (HBeAg)-positive and 31.7% HBeAg-negative. BCP/PC mutations were more common in HBeAg-negative than in HBeAg-positive patients (p < 0.0001). Compared to genotype D patients, those harboring non-D genotypes were more frequently males (p = 0.023), HBeAg-positive (p < 0.001), had higher bilirubin (p = 0.014) and viremia (p = 0.034) levels and less frequently carried BCP/PC mutations (p < 0.001). Non-D genotype patients more often were from Central Italy (p = 0.001) and reported risky sexual exposure (p = 0.021). Two patients had received vaccination before AHB: one harbored genotype F; the other showed a S gene mutation. Four patients developed fulminant AHB; mutations were found in 2 of 3 patients who underwent BCP/PC sequencing. After a 6-month follow-up, only 2 (2.8%) patients developed persistent infection. CONCLUSION: AHB by non-D genotypes is increasing in Italy and is associated with risky sexual exposure. The ability of some genotypes to cause persistent and/or severe infection in Italy warrants larger studies for clarification.

[Universal vaccination against varicella in Italy: the same opportunity for all children]. / La vaccinazione universale contro la varicella in Italia: una questione di equità.

Varicella is an infectious disease still frequent in Italy, where 8 out 20 Regions have adopted universal vaccination programs starting from 2003. Accordingly to National Vaccination Plan, all Regions should introduce universal varicella vaccination in 2015. An independent multidisciplinary group of experts met to discuss some debated questions. The available evidence of varicella vaccine efficacy in the 8 Regions was evaluated and the evidence of safety of monovalent and combined varicella vaccines are presented. The strategy for introducing universal varicella vaccine in the pediatric immunization schedule is discussed. The expert group concludes that available evidence supports the active offer of varicella vaccine in all Italian Regions and that catch up programs for susceptible cohorts should be encouraged.

Surveillance of hepatitis A virus in urban sewages and comparison with cases notified in the course of an outbreak, Italy 2013.

BACKGROUND: Over the past 20 years, Hepatitis A notifications in Italy have been in decline. Since the beginning of 2013 however, Italy has been experiencing a foodborne hepatitis A outbreak caused by genotype IA, involving hundreds of cases. Consumption of frozen mixed berries was deemed the potential vehicle of infection.We aimed to investigate the spread of hepatitis A virus (HAV) in Italy through the monitoring of urban sewages collected at Wastewater Treatment Plants (WTPs) and a subsequent comparison of environmental surveillance data with data from the clinical surveillance performed during the epidemic. METHODS: The study covered 15 months, from July 2012 to September 2013, comprising the outbreak and the preceding six months. Environmental surveillance consisted of the analysis of urban sewage samples collected at 19 WTPs in seven of the Italian regions most affected by the epidemic. HAV isolates were detected and typed using a nested RT-PCR targeting the VP1/2A junction. Parallel clinical surveillance was performed by the sentinel surveillance system for acute viral hepatitis (SEIEVA) and by the ministerial Central Task Force on Hepatitis A, established with the purpose of determining the source of the outbreak and adopting appropriate outbreak control strategies. RESULTS: A total of 38/157 wastewater samples (24.2%) were positive for HAV, 16 collected in 2012 and 22 in 2013. Several HAV strains were detected, including the IA variant implicated in the outbreak and isolated from clinical cases over the same period. The vast majority of sequences belonged to genotype IB. Interestingly however, although these included variants related to strains that had been involved in past Italian epidemics, none were detected in recent clinical samples, probably due to underreporting or asymptomatic circulation. Conversely, a number of sequences were identified in clinical samples that were not found in wastewaters. CONCLUSIONS: The percentage of sewage samples detected as HAV-positive in this study are consistent with the classification of Italy as a country with low/intermediate endemicity. A combined environmental/clinical surveillance is able to provide a more complete picture of the spread of HAV and of the genotypes circulating in the population, allowing a better understanding of changes in disease trends.

Multiple clusters of A(H1N1)pdm09 virus circulating in severe cases of influenza during the 2010-2011 season: a phylogenetic and molecular analysis of the neuraminidase gene.

The molecular characterization of circulating influenza A viruses is crucial to detect mutations potentially involved in increased virulence, drug resistance and immune escape. A molecular and phylogenetic analysis of A(H1N1)pdm09 neuraminidase (NA) gene sequences from different patient categories defined according to the severity of influenza infection were analyzed. A total of 126 influenza A(H1N1)pdm09 positive samples from patients with severe infections in comparison with those with moderate and mild infections was performed in Lombardy (Northern Italy, nearly 10 million inhabitants) during the 2010-2011 season. NA sequences included in this study segregated into five distinct clusters. Nineteen amino acid substitutions were detected exclusively in NA sequences of viruses identified in patients with severe or moderate influenza infection. Three of them (F74S, S79P, E287K) were observed in virus strains with the 222G/N hemagglutinin mutation. None of NA sequences under study had mutations related to the resistance to the NA inhibitors. Four out of 126 (3.2%) NA sequences from patients with severe infection lost a N-linked glycosylation site due to the change from N to K at residue 386. Two additional N-linked glycosylation sites in the NA stalk region (residues 42 and 44) were found in 12 (9.5%) NA sequences. Sporadic NA mutations were detected in NA viral sequences from critically ill patients, and no variants with reduced sensitivity to NA inhibitors were observed either in treated or untreated patients.

Switched memory B cells maintain specific memory independently of serum antibodies: the hepatitis B example.

The immunogenicity of a vaccine is conventionally measured through the level of serum Abs early after immunization, but to ensure protection specific Abs should be maintained long after primary vaccination. For hepatitis B, protective levels often decline over time, but breakthrough infections do not seem to occur. The aim of this study was to demonstrate whether, after hepatitis B vaccination, B-cell memory persists even when serum Abs decline. We compared the frequency of anti-hepatitis-specific memory B cells that remain in the blood of 99 children five years after priming with Infanrix -hexa (GlaxoSmithKline) (n=34) or with Hexavac (Sanofi Pasteur MSD) (n=65). These two vaccines differ in their ability to generate protective levels of IgG. Children with serum Abs under the protective level, <10 mIU/mL, received a booster dose of hepatitis B vaccine, and memory B cells and serum Abs were measured 2 wk later. We found that specific memory B cells had a similar frequency in all children independently of primary vaccine. Booster injection resulted in the increase of memory B cell frequencies (from 11.3 in 10(6) cells to 28.2 in 10(6) cells, p<0.01) and serum Abs (geometric mean concentration, GMC from 2.9 to 284 mIU/mL), demonstrating that circulating memory B cells effectively respond to Ag challenge even when specific Abs fall under the protective threshold.

Hepatitis B Vaccination: A Historical Overview with a Focus on the Italian Achievements.

Vaccination is the most effective way to control and prevent acute and chronic hepatitis B, including cirrhosis and HCC, on a global scale. According to WHO recommendations, 190 countries in the world have introduced hepatitis B vaccination into their national childhood immunization programs with an excellent profile of safety, immunogenicity, and effectiveness. Following vaccination, seroprotection rates are close to 100% in healthy children and over 95% in healthy adults. Persistence of anti-HBs is related to the antibody peak achieved after vaccination. The peak is higher the longer the antibody duration is. Loss of anti-HBs does not necessarily mean loss of immunity since most vaccinated individuals retain immune memory for HBsAg and rapidly develop strong anamnestic responses when boosted. Evidence indicates that the duration of protection can persist for at least 35 years after priming. Hence, booster doses of vaccines are currently not recommended to sustain long-term immunity in healthy vaccinated individuals. In Italy, vaccination against hepatitis B is met with success. In 2020, Italy became one of the first countries in Europe to be validated for achieving the WHO regional hepatitis B control targets.

Hepatitis E in Italy: a long-term prospective study.

BACKGROUND & AIMS: In developed countries, hepatitis E is usually associated with travelling to endemic areas, but a growing number of sporadic cases are also seen in patients with no travel history. The aim of this study was to assess the impact and the molecular epidemiology of hepatitis E in Italy. METHODS: Between January 1994 and October 2009, we analyzed 651 patients with acute non-A-C hepatitis. Diagnosis of hepatitis E was based on the presence of IgM anti-HEV and/or the detection of HEV RNA by RT-PCR. Viral isolates were sequenced and phylogenetically characterized. RESULTS: A total of 134 out of 651 (20.6%) patients tested had acute hepatitis E. All were anti-HEV IgM and IgG positive and 96 (71.6%) were also positive for HEV RNA. Moreover, 39 (6%) patients were anti-HEV IgG positive but negative for both IgM anti-HEV and HEV RNA. A total of 109 (81.3%) patients developed hepatitis E travelling to endemic areas, 3 (2.3%) acquired intra-familial infection from relatives who developed travel-related disease, while 22 (16.4%) patients denied having travelled abroad. In all patients, acute disease had a self-limited course with ALT normalization within 3-6 weeks. Phylogenetic analysis of 39 isolates from patients with a travel-related disease showed that they belonged to genotype 1, while sequences from five patients with autochthonous hepatitis E belonged to genotype 3. CONCLUSIONS: In Italy, most cases of hepatitis E are travel related, caused by viral genotype 1, while autochthonous cases are caused by genotype 3. The prevalence of genotype 3 among pigs and boars suggests that HEV infection may have zoonotic origins in non-endemic countries.

Co-circulation of genetically distinct human metapneumovirus and human bocavirus strains in young children with respiratory tract infections in Italy.

The discovery of human Metapneumovirus (hMPV) and human Bocavirus (hBoV) identified the etiological causes of several cases of acute respiratory tract infections in children. This report describes the molecular epidemiology of hMPV and hBoV infections observed following viral surveillance of children hospitalized for acute respiratory tract infections in Milan, Italy. Pharyngeal swabs were collected from 240 children ≤3 years of age (130 males, 110 females; median age, 5.0 months; IQR, 2.0-12.5 months) and tested for respiratory viruses, including hMPV and hBoV, by molecular methods. hMPV-RNA and hBoV-DNA positive samples were characterized molecularly and a phylogenetical analysis was performed. PCR analysis identified 131/240 (54.6%) samples positive for at least one virus. The frequency of hMPV and hBoV infections was similar (8.3% and 12.1%, respectively). Both infections were associated with lower respiratory tract infections: hMPV was present as a single infectious agent in 7.2% of children with bronchiolitis, hBoV was associated with 18.5% of pediatric pneumonias and identified frequently as a single etiological agent. Genetically distinct hMPV and hBoV strains were identified in children examined with respiratory tract infections. Phylogenetic analysis showed an increased prevalence of hMPV genotype A (A2b sublineage) compared to genotype B (80% vs. 20%, respectively) and of the hBoV genotype St2 compared to genotype St1 (71.4% vs. 28.6%, respectively). Interestingly, a shift in hMPV infections resulting from A2 strains has been observed in recent years. In addition, the occurrence of recombination events between two hBoV strains with a breakpoint located in the VP1/VP2 region was identified.

Transmission of hemagglutinin D222G mutant strain of pandemic (H1N1) 2009 virus.

A pandemic (H1N1) 2009 virus strain carrying the D222G mutation was identified in a severely ill man and was transmitted to a household contact. Only mild illness developed in the contact, despite his obesity and diabetes. The isolated virus reacted fully with an antiserum against the pandemic vaccine strain.

Epidemiological and clinical features of rotavirus among children younger than 5 years of age hospitalized with acute gastroenteritis in Northern Italy.

BACKGROUND: Rotavirus is the major cause of acute gastroenteritis and severe dehydrating diarrhea in young children. METHODS: To estimate the proportion of hospital admissions for rotavirus acute gastroenteritis and identify the circulating G and P genotypes among children under five years of age, we conducted a prospective observational study from January to December 2008, recruiting children consecutively admitted to six hospitals in Milan and nearby towns in northern Italy. Typing was done on stool samples by reverse transcriptase polymerase chain reaction amplification. RESULTS: Of the 521 stool samples from children with acute gastroenteritis, 34.9% (95%CI, 30.8 to 39.2%) were rotavirus-positive. Two thirds (67.6%) were under two years of age, and 13.2% were under six months. The predominant G type was G1 (40.7%), followed by G9 (22.5%), G2 (13.2%), G3 (5.5%), G4 (3.8%) and G10 (1.6%). Twenty-one (11.7%) mixed-G infections were identified: G1+G10 (8.8%); G1+G9 (1.6%); and G2+G10 (1.2%). Only P[8] (67.6%) and P[4] (12.6%) types were P genotyped. The predominant single G/P combination was G1P[8] (39.7%), followed by G9P[8] (25.3%), G2P[4] (14.3%), and G3P[8] (4.1%). All G-mixed types combined with P[8]. CONCLUSIONS: These findings show an high prevalence of rotavirus infections among children admitted to hospital for acute gastroenteritis caused by different rotavirus strains circulating in the area studied.

Prevalence, incidence and residual risk of transfusion-transmitted hepatitis B virus infection in Italy from 2009 to 2018.

BACKGROUND: In Italy, the use of nucleic acid testing for hepatitis B virus (HBV) in donor screening has allowed the detection of infections in the window phase, as well as the presence of occult infections which could potentially be transmitted. The aim of this study was to analyse the trends of epidemiological data focused on HBV infection in blood donors and to estimate the residual risk of transmitting HBV from both the window phase and occult infection over a 10-year period in Italy. MATERIALS AND METHODS: Data were obtained from the Italian Haemovigilance System which includes the results of screening tests for transfusion transmissible infections. During the period of this survey (2009-2018), the molecular methods used for HBV screening were transcription-mediated amplification and polymerase chain reaction tests. Prevalence and incidence were calculated. The residual risk was estimated by applying the incidence-window period model for acute cases and a more recently reported model for estimating the risk due to occult infections. RESULTS: A total of 17,424,535 blood donors and 30,842,794 donations were tested for HBV. Altogether, 6,250 donors tested positive for HBV markers: 4,782 (175.6×105) were first time donors and 1,468 (10.0×105) were repeat donors. The prevalence of HBV markers in first time donors was 275.9×105 in 2009, declining to 143.6×105 in 2018. The incidence of new infections was 3.37×105 in 2009 and 2.17×105 in 2018. The overall residual risk for HBV amounted to 1 in 2,566,854 donations calculated as the sum of risks of both acute infections in the window period (1 in 5,835,306 donations) and occult infections (1 in 4,582,270 blood units). DISCUSSION: In Italy, the residual risk of transfusing a blood unit infected with HBV, both from window phase and occult infections, is currently very low, amounting to levels that can be considered tolerable.

Molecular characterization of influenza viruses circulating in Northern Italy during two seasons (2005/2006 and 2006/2007) of low influenza activity.

The influenza activity and circulation of influenza viruses in Lombardy (the most populous Italian region) were observed during two consecutive seasons (2005/2006 and 2006/2007) characterized by low influenza activity by the Italian Influenza Surveillance Network. The molecular characteristics of circulating viruses were analyzed to evaluate the introduction of new variants and emergence of vaccine-escape viruses. In both seasons, the epidemic in Lombardy was sustained almost exclusively by influenza A viruses, accounting for 80.5% and 93.6% of total detections, respectively, and the co-circulation of A/H3 viruses belonging to distinct phylogenetic groups was observed. The A/H1N1 viruses isolated during the 2005/2006 season were closely related to A/New Caledonia/20/99, while the hemagglutinin (HA) sequences of the A/H1N1 viruses from the 2006/2007 season exhibited a greater diversity. These viruses were A/Solomon Islands/3/2006-like and showed several variants. All B isolates were similar to B/Malaysia/2506/2004 belonging to the B/Victoria/2/87-lineage. Influenza B virus was the dominant virus in Europe in the 2005/2006 season and accounted for the 20% of total detections in Lombardy. Overall, the viruses studied presented heterogeneity in their HA sequences suggesting the circulation of a miscellaneous set of variants during the two seasons notwithstanding the medium-low activity of influenza. The importance of virological surveillance of influenza viruses is recognized widely and the molecular characterization of the viruses, especially in vaccinated subjects, is of particular importance to evaluate the introduction and circulation of new variants.

Impact of nucleic acid testing for hepatitis B virus, hepatitis C virus, and human immunodeficiency virus on the safety of blood supply in Italy: a 6-year survey.

BACKGROUND: Nucleic acid testing (NAT) for hepatitis C virus (HCV) and human immunodeficiency virus (HIV) has been implemented in several European countries and in the United States, while hepatitis B virus (HBV) NAT is still being questioned by opinions both in favor and against such an option, depending on the HBV endemicity, health care resources, and expected benefits. STUDY DESIGN AND METHODS: This survey was aimed to assess the NAT impact in improving the safety of blood supply in Italy, 6 years after implementation. The study involved 93 Italian transfusion centers and was carried out in 2001 through 2006. A total of 10,776,288 units were tested for the presence of HCV RNA, 7,932,430 for HIV RNA, and 3,405,497 for HBV DNA, respectively. RESULTS: Twenty-seven donations or 2.5 per million tested were HCV RNA-positive/anti-HCV-negative; 14 or 1.8 per million units tested were HIV RNA-positive/anti-HIV-negative; and 197 or 57.8 per million donations tested were HBV DNA-positive/hepatitis B surface antigen-negative. Of the latter, 8 (2.3/10(6)) were collected from donors in the window phase of infection and 189 (55.5/10(6)) from donors with occult HBV. Sixty-eight percent of the latter donors had hepatitis B surface antibody, 74.5 percent of whom with concentrations considered protective (>or=10 mIU/mL). CONCLUSION: NAT implementation has improved blood safety by reducing the risk of entering 2.5 HCV and 1.8 HIV infectious units per million donations into the blood supply. The yield of NAT in detecting infectious blood before transfusion was higher for HBV than for HCV or HIV. However, the benefit of HBV NAT in terms of avoided HBV-related morbidity and mortality in blood recipients needs to be further evaluated.

Prevalence, incidence and residual risk of transfusion-transmitted hepatitis C virus and human immunodeficiency virus after the implementation of nucleic acid testing in Italy: a 7-year (2009-2015) survey.

BACKGROUND: In Italy nucleic acid testing (NAT) became mandatory for hepatitis C virus (HCV) in 2002 and for human immunodeficiency virus (HIV) and hepatitis B virus in 2008. The aim of this study was to monitor the incidence and prevalence of HIV and HCV infections in Italian blood donors and the current residual risk of these infections after the introduction of NAT. MATERIALS AND METHODS: The Italian national blood surveillance system includes data from tests used to screen for transfusion-transmissible infections. During the period of this survey (2009-2015), the NAT methods used were the transcription-mediated amplification test, for individual donor testing, and polymerase chain reaction analysis, mainly for pools of six donors. Prevalence and incidence were calculated. Three published formulae were applied to estimate the residual risk (the window period ratio model and the formulae recommended by the European Medicines Agency and the World Health Organization). RESULTS: Overall, 12,258,587 blood donors and 21,808,352 donations were tested for HCV and HIV. The prevalence of HCV decreased from 110.3×105 to 58.9×105 in years 2009 and 2015, respectively, while that of HIV remained stable over time (15.5×105 vs 15.4×105). The incidence of HCV decreased from 3.19×105 in 2009 to 1.58×105 in 2015, while the incidence of HIV did not show any significant fluctuations (average incidence 4.39×105). The residual risk of a viraemic unit entering the blood supply was estimated to be 0.077×106 or 1 in 12,979,949 donations for HCV and 0.521×106 or 1 in 1,917,250 for HIV, according to the window period ratio model, and lower with the other two formulae. DISCUSSION: HCV infection has declined over time in both first-time and repeat donors, while the data for HIV infection are stable. All three methods employed in this study showed that the residual risk of transmitting HCV or HIV through an infected blood unit is currently very low in Italy, but there are considerable differences in estimates between methods. Thus, harmonisation of these methods is advisable.