Laura Bubba

Detection and distribution of culturable Human Enteroviruses through environmental surveillance in Milan, Italy.

Human Enteroviruses (HEVs) infections have a significant impact on public health, being implicated in outbreaks of meningitis, encephalitis, hand‐foot‐mouth disease and other acute and chronic manifestation. In the strategic plan for poliomyelitis eradication, the environmental surveillance of poliovirus (PV) has been identified by the World Health Organization (WHO) as an activity that can complement the surveillance of polio. Having wastewater samples available for PV surveillance allows us to study nonpolio enteroviruses (NPEVs) circulating in the study population, which are widely spread.

Two cases of neonatal human parechovirus 3 encephalitis

We report 2 neonates with human parechoviruses type 3 encephalitis. Both newborns presented with fever, irritability and seizures. Cerebrospinal fluid analyses were normal, but magnetic resonance imaging revealed white matter damage, suggesting human parechoviruse infection. Human parechoviruses type 3-RNA was detected in cerebrospinal fluid samples and in blood, stool, urine and respiratory samples, indicating the dissemination of the virus.

Ten years (2004-2014) of influenza surveillance in Northern Italy

As the regional influenza reference centre operating within the Italian network InfluNet, here we report data on virological and epidemiological surveillance of influenza, as well as on the vaccination coverage rates achieved in Lombardy (Northern Italy) over 10 consecutive winter seasons (2004–2014). Over the past 10 years, influenza vaccine coverage declined both in the general population (from 15.7% in 2004–2005 to 11.7% in 2013–2014) and in the vaccine-target population of individuals ≥65-y-of-age (from 65.3% in 2004–2005 to 48.6% in 2013–2014) and is far below the minimum planned threshold level (75%). The highest influenza-like illness (ILI) rates were recorded during the 2004–2005 and 2009–2010 epidemics (peak incidence: 12.04‰ and 13.28‰, respectively). Both seasons were characterised by the introduction of novel viral strains: A/Fujian/411/2002(H3N2) (a drifted hemagglutinin variant) and A/California/7/2009(H1N1) pandemic virus (a swine origin quadruple reassortant), respectively. Because the antigenic match between vaccine and circulating strains was good in both of these seasons, a relevant proportion of cases may have been prevented by vaccination. A different situation was observed during the 2011–2012 season, when ILI morbidity rates in individuals ≥65-y-of-age were 1.5–6-fold higher than those registered during the other epidemics under review. The higher morbidity resulted from the circulation during the 2011–2012 season of an A/Victoria/361/2011(H3N2)-like variant that presented a reduced genetic match with the A(H3N2) strain included in the 2011–2012 vaccine composition. The continuous surveillance of the characteristics of circulating viruses is an essential tool for monitoring their matching with seasonal vaccine strains. Strategies to increase coverage rates are warranted.

What people know about congenital CMV: an analysis of a large heterogeneous population through a web-based survey

BackgroundCongenital CMV (cCMV) infection is a serious public health issue due to both its worldwide prevalence and the severe and permanent impairments it causes. However, awareness of this infection is low in the general population and among pregnant women, and it also seems to be generally disregarded by healthcare providers. The identification of factors behind this inadequate level of knowledge could provide a basis for future preventive measures. This study aimed at evaluating awareness of CMV and cCMV infection and its correlation with socio-demographic variables in a general population.MethodsThe survey was carried out by computer-assisted web interviewing (CAWI). A questionnaire was sent via e-mail to the 70,975 individuals who comprised the whole population (students, administrative staff, teaching staff) of Milan University, Italy in 2015.ResultsOut of the 10,190 respondents, 5,351 (52.5 %) had already heard of CMV but only 3,216 (31.8 %) knew that this virus could be implicated in congenital infection. Urine and breastfeeding were the least recognized transmission routes for CMV infection; less than half of respondents accurately identified the right symptoms and sequelae caused by cCMV infection. The correct hygienic measures against cCMV infection were identified in percentages ranging from 55.6 to 75 % depending on the measures proposed but about one in three of interviewees deemed those measures unnecessary in the event of a pregnant woman already being CMV seropositive. From the mean knowledge scores the most complete quality of awareness of CMV turned out to be linked to childbearing-age (25–40 year) and with not having children, even if results for non-parents showed less of them having heard of cCMV than parents.ConclusionOur results indicate a limited and confused awareness of cCMV infection in a large, fairly young and well-educated Italian population.

A 4-year Study on Epidemiologic and Molecular Characteristics of Human Parechoviruses and Enteroviruses Circulating in Children Younger Than 5 Years in Northern Italy.

Background: Human parechovirus (HPeV) and enterovirus (EV) infections are widespread and can lead to a broad range of symptoms, from the common cold to severe disease (SD). Because of the lack of Italian data, this 4-year retrospective cross-sectional study aimed to investigate the frequency, seasonality and molecular characteristics of EV and HPeV circulating in children younger than 5 years. Methods: A total of 812 samples were collected from children ⩽5 years (56.5% males; median age: 20.6 months; interquartile range: 30.1 months) from September 2010 to August 2014. Two real-time RT-PCR assays were used for EV/HPeV and EV-D68 detection. Phylogenetic analysis was performed on the EV-VP1 gene and the HPeV–VP3/VP1 junction. Results: 16.1% and 5.2% of samples were EV- and HPeV-positive, respectively. One sample was EV-D68-positive. The majority (nearly 80%) of EV/HPeV-positive samples was detected in children ⩽3 years, during the summer/autumn seasons. The risk of EV infection was higher in children presenting with SD, whereas the risk of infection from HPeV was higher in infants ⩽1 year. Most (61.7%) of molecularly characterized EVs belonged to species B, followed by A (29.4%). The majority (66.7%) of characterized HPeVs were type 1, followed by types 3 (20%) and 6 (13.3%). Conclusions: This study shows the significant impact of EV/HPeV circulation in children, particularly among those ⩽3 years and during and early autumn, with different pattern of viral strains. The implementation of a national surveillance system could clarify the epidemiologic and clinical characteristics of these viruses in the general population.

Surveillance and vaccination coverage of measles and rubella in Northern Italy.

Measles and rubella are infectious diseases and humans are the only reservoir of these infections. Effective vaccines are available with the potential for measles (MV) and rubella (RuV) virus eradication. According to the World Health Organisation guidelines, a national plan was approved in Italy in 2013 to achieve the MV/RuV elimination by 2015, and active MV/RuV integrated surveillance initiated. Towards this purpose, a regional laboratory centre was set up on 1 September 2013 in Lombardy, Northern Italy. This paper aimed at: (1) evaluating measles-mumps-rubella (MMR) vaccine coverage and MV/RuV notified cases retrospectively; and (2) presenting the results of MV/RuV integrated surveillance (laboratory confirmed and viral genetic profiles). The 95% target for MMR vaccine coverage was achieved in 2001, and coverage increased until 2007 (96.6%), but then a decreasing trend was observed. Since 2000 to 2014, 3026 rubella cases were notified, with nearly 58% of them in the 2002 epidemic. From 2009, less than 45 RuV cases per year were reported. From 2000 to 2014, 5024 measles cases were notified. Since 2008, three large outbreaks (in 2008, 2011, and 2013) were observed. From data obtained during our surveillance activity, there were no rubella cases, and 57.5% (46/80) collected samples were MV-positive by real-time RT-PCR. A fragment of the MV N gene was sequenced from 37 MV-positive samples; D8, D9, and B3 genotypes were detected. Data obtained retrospectively and from active surveillance underline the necessity to achieve and maintain high vaccination coverage and to improve surveillance and the effectiveness of healthcare actions.

Surveillance of acute flaccid paralysis (AFP) in Lombardy, Northern Italy, from 1997 to 2011 in the context of the national AFP surveillance system

An Acute Flaccid Paralysis (AFP) surveillance system was set up in Lombardy (Northern Italy) in 1997 in the framework of the national AFP surveillance system, as part of the polio eradication initiative by the World Health Organization (WHO). This surveillance system can now be used to detect Poliovirus (PV) reintroductions from endemic countries. This study aimed at describing the results of the AFP surveillance in Lombardy, from 1997 to 2011. Overall, 131 AFP cases in Lombardy were reported with a mean annual incidence rate of 0.7/100 000 children <15 years of age (range: 0.3/100 000–1.1/100 000). The sensitivity of the surveillance system was optimal from 2001–2003. The monthly distribution of AFP cases was typical with peaks in November, in January, and in March. The major clinical diagnoses associated with AFP were Guillain-Barré Syndrome (GBS, 40%) and encephalomyelitis/myelitis (13%). According to the virological results, no poliomyelitis cases were caused by wild PV infections, but two Vaccine-Associated Paralytic Paralysis (VAPP) cases were reported in 1997 when the Sabin oral polio vaccine (OPV) was still being administered in Italy. Since a surveillance system is deemed sensitive if at least one case of AFP per 100,000 children <15 years of age is detected each year, our surveillance system needs some improvement and must be maintained until global poliovirus eradication will be declared.

Surveillance of poliomyelitis in Northern Italy: Results of acute flaccid paralysis surveillance and environmental surveillance, 2012–2015

ABSTRACT Although in the last years poliovirus (PV) transmission has been reported at the lowest levels ever recorded, the spread of virus from endemic countries endures; the high levels of immigration flows across the Mediterranean Sea jeopardize Italy for PV reintroduction. The World Health Organization (WHO) strategic plan for global poliomyelitis (polio) eradication indicates the nationwide surveillance of Acute Flaccid Paralysis (AFP) as the gold standard for detecting cases of polio. In addition, the Environmental Surveillance (ES), seeking the presence of PV and Non-Polio Enterovirus (NPEV) in sewage, is recognized as a powerful tool to confirm PV circulation in absence of AFP cases, especially in polio-free countries. Here we report the results of AFP surveillance (AFPS) and ES in Lombardy (Northern Italy) from 2012 to 2015. Forty-eight AFP cases were identified during the study period. No AFP case was caused by PV infection. NPEVs were identified in 6.3% (3/48) of AFP cases. The annual AFP incidence rate was 0.87/100′000 children <15 y in 2012, 1.42/100′000 in 2013, 1.02/100′000 in 2014, and 0.47/100′000 in 2015; according to WHO indicators, the sensitivity of AFPS was adequate in 2013 and 2014. Completeness of case investigation raised progressively during the study period to achieve the WHO standards in 2014 (92.3%) and 2015 (100%). Completeness of follow-up increased from 72.7% in 2012 to 100% in 2014. In the framework of the ES conducted in Milan, 268 wastewater samples were collected from 2012 to 2015 and no PVs were isolated. In contrast, NPEVs were detected in 65.3% (175/268) of samples. All NPEVs characterized belonged to enterovirus species B: echovirus type 11, 6 and 3 were the most frequently detected viruses, representing 29.1% (41/141), 20.6% (29/141) and 9.2% (13/141) of genotyped NPEVs, respectively. Keeping strong and encouraging both AFPS and ES is crucial to ensure that PV will not return unnoticed in Italy - as well as in other polio-free countries - and, as a final point, to achieve the global polio eradication goal.

Frequency of respiratory virus infections and next-generation analysis of influenza A/ H1N1pdm09 dynamics in the lower respiratory tract of patients admitted to the ICU

Recent molecular diagnostic methods have significantly improved the diagnosis of viral pneumonia in intensive care units (ICUs). It has been observed that 222G/N changes in the HA gene of H1N1pdm09 are associated with increased lower respiratory tract (LRT) replication and worse clinical outcome. In the present study, the frequency of respiratory viruses was assessed in respiratory samples from 88 patients admitted to 16 ICUs during the 2014–2015 winter-spring season in Lombardy. Sixty-nine out of 88 (78.4%) patients were positive for a respiratory viral infection at admission. Of these, 57/69 (82.6%) were positive for influenza A (41 A/H1N1pdm09 and 15 A/H3N2), 8/69 (11.6%) for HRV, 2/69 (2.9%) for RSV and 2/69 (2.9%) for influenza B. Phylogenetic analysis of influenza A/H1N1pdm09 strains from 28/41 ICU-patients and 21 patients with mild respiratory syndrome not requiring hospitalization, showed the clear predominance of subgroup 6B strains. The median influenza A load in LRT samples of ICU patients was higher than that observed in the upper respiratory tract (URT) (p<0.05). Overall, a greater number of H1N1pdm09 virus variants were observed using next generation sequencing on partial HA sequences (codons 180–286) in clinical samples from the LRT as compared to URT. In addition, 222G/N/A mutations were observed in 30% of LRT samples from ICU patients. Finally, intra-host evolution analysis showed the presence of different dynamics of viral population in LRT of patients hospitalized in ICU with a severe influenza infection.

Burden of pediatrics hospitalizations associated with Rotavirus gastroenteritis in Lombardy (Northern Italy) before immunization program

AIM Rotavirus is recognized as the main cause of acute gastroenteritis in children under 5 years old, representing a considerable public health problem with a great impact on social and public health costs in developed countries. This study aims to assess the frequency and the epidemiological aspect of the hospitalization associated with Rotavirus-gastroenteritis in Lombardy, Northern Italy, from 2005 to 2011. METHODS The Lombardy Hospital Discharge Database was inquired from the official data of the Italian Ministry of Health and investigated for acute gastroenteritis (ICD9-CM code for bacteria, parasitic, viral and undetermined etiologic diarrhea) in primary and secondary diagnosis in children ≤ 5 years, between 2005 and 2011. RESULTS Out of the 32 944 acute-gastroenteritis hospitalizations reported in Lombardy, the 50.8% was caused by Rotavirus infection; of these, the 65.5% were reported in primary diagnosis. The peak of Rotavirus-gastroenteritis hospitalization was observed in February-March in children < 2 years old, with a cumulative prevalence of 64.5%. Patients admitted to hospital with diarrhea of undetermined etiology (about 14% of overall acute-gastroenteritis) showed epidemiological characteristics similar to the Rotavirus-gastroenteritis, suggesting that the virus infection could also be involved in at least some of these. CONCLUSION Our data confirm that Rotavirus are the most important agents involving in acute gastroenteritis hospitalizations. The use of Hospital Discharge Database had proved to be a simple tool to estimate the burden and to describe the epidemiological characteristics of Rotavirus gastroenteritis and could be used as a surveillance activity before and after the introduction of mass vaccination at national and regional level in Italy.