Melissa Baggieri

Circulation of West Nile virus lineage 1 and 2 during an outbreak in Italy.

In 2011, from 26 September to 16 October, a small outbreak of West Nile virus (WNV) disease occurred on the island of Sardinia (Italy). According to the national case definition, six cases with acute neurological disease were confirmed in hospitalized patients, and four of them died; one of these was only 34 years old. In two case, WNV RNA was detected in urine, suggesting renal involvement. Sequence analysis showed lineage 1 and 2 circulation.

Measles elimination in Italy: data from laboratory activity, 2011–2013

BACKGROUND The European Regional Office of the World Health Organization developed a strategic approach to halt the indigenous transmission of measles in its 53 Member States by 2015, World Health Organization [1]. Many European countries, including Italy began the implementation of national programs to reach this goal. OBJECTIVES To describe and discuss the results of laboratory activity in measles surveillance, performed from January 2011 to December 2013 by the Italian National Reference Laboratory for Measles and Rubella. STUDY DESIGN Samples of suspected measles cases were collected from different Italian regions to confirm clinical diagnosis. Anti-measles IgM antibodies detection by Enzyme-Linked Immunosorbent Assay and/or molecular detection by Reverse Transcriptase-Polymerase Chain Reaction assay were performed. Positive samples were sequenced for viral characterization. RESULTS AND CONCLUSIONS According to results from the National Reference Laboratorys activity urine and blood seem to be the best specimens for measles laboratory surveillance. Phylogenetic analysis revealed a co-circulation of the genotypes D4 and D8 during the reviewed period, a cluster of B3 and sporadic cases of D9 and H1.

Ongoing outbreak with well over 4,000 measles cases in Italy from January to end August 2017 − what is making elimination so difficult?

We report an ongoing measles outbreak in Italy, with over 4,400 cases reported in 20 Regions from January to August 2017. Median age was 27 years, 88% of the cases were unvaccinated. The highest incidence was in infants below one year of age and 7% of cases occurred among healthcare workers. Three deaths occurred and two cases of encephalitis were reported. Wide immunity gaps and nosocomial transmission are major challenges to measles elimination in Italy.

Ongoing large measles outbreak with nosocomial transmission in Milan, northern Italy, March–August 2017

A large measles outbreak has been ongoing in Milan and surrounding areas. From 1 March to 30 June 2017, 203 measles cases were laboratory-confirmed (108 sporadic cases and 95 related to 47 clusters). Phylogenetic analysis revealed the co-circulation of two different genotypes, D8 and B3. Both genotypes caused nosocomial clusters in two hospitals. The rapid analysis of epidemiological and phylogenetic data allowed effective surveillance and tracking of transmission pathways.

Measles re-emergence in Northern Italy: Pathways of measles virus genotype D8, 2013–2014

Molecular surveillance and advanced phylogenetic methods are important tools to track the pathways of Measles virus (MV) genotypes, provide evidence for the interruption of endemic transmission and verify the elimination of the disease. The aims of this study were to describe the genetic profile of MV genotype D8 (D8-MV) strains circulating in Northern Italy (Lombardy Region) during the 2013-2014 period and to analyze the transmission chains and estimate the introduction time points using a phylogenetic approach. Forty-four strains of D8-MV identified from 12 outbreaks and 28 cases reported as sporadic were analyzed. Molecular analysis was performed by sequencing the highly variable 450nt region of the N gene of MV genome (N-450), as recommended by the WHO. Phylogenetic analyses and tree time-scaled reconstruction were performed with BEAST software. We could trace back the transmission pathways that resulted in three chains of transmission, two introductions with limited spread (two familiar outbreaks), and two single introductions (true sporadic cases). The D8-Taunton transmission chain, which was involved in 7 outbreaks and 13 sporadic cases, was endemic during the studied period. Furthermore, two novel local variants emerged independently in March 2014 and caused two transmission chains linked to at least 3 outbreaks. Overall, viral diversity was high and strains belonging to 5 different variants were identified. The results of this study clearly demonstrate that multiple lineages of D8-MV co-circulated in Northern Italy. Measles can be considered a re-emerging disease in Italy and additional efforts are necessary to achieve measles elimination goal.

Molecular epidemiology of measles virus in Italy, 2002–2007

BackgroundThe European Regional Office of the World Health Organization (WHO/Europe) developed a strategic approach to halt the indigenous transmission of measles in its 53 Member States by 2015. In view of the goal of measles elimination, it is of great importance to assess the circulation of wild-type measles virus (MV). Genetic analysis is indispensable to understand the epidemiology of measles.MethodsUrine and saliva samples were collected between May 2002 and December 2007, in order to find the origins and routes of wild type measles virus circulation. RT-PCR was performed on a total of 414 clinical samples of patients from different Italian regions. The results confirmed the genome presence in 199 samples, out of which 179 were sequenced. The sequences were genotyped by comparing the fragment coding for the carboxyl terminus of the nucleoprotein (450 nucleotides) with that one of the WHO reference strains.ResultsFrom the year 2002 to the year 2007 phylogenetic analysis of measles sequences showed a predominant circulation of the D7 genotype in the Italian territory for the years 2002–2004. This genotype was replaced by D4 and B3 genotypes in the biennium 2006–2007. During the same period C2, A, D5 and D8 genotypes were also detected.ConclusionsGenetic characterization of wild-type MV provides a means to study the transmission pathways of the virus, and is an essential component of laboratory-based surveillance. Knowledge of currently circulating measles virus genotype in Italy will help in monitoring the success of the measles elimination programme and will contribute to evaluate the effectiveness of future vaccination campaigns.

Genotyping of circulating measles strains in Italy in 2010

INTRODUCTION The European Regional Office of the World Health Organization developed a strategic approach to stop the indigenous transmission of measles in its 53 Member States by 2015. In Italy, laboratory surveillance activity is implemented by the National Reference Laboratory for Measles and Rubella at the Italian National Institute of Health (Istituto Superiore di Sanità, Rome). The role of the National Reference Laboratory is to strengthen surveillance systems through rigorous case investigation and laboratory confirmation of suspected sporadic cases and outbreaks. Genetic characterization of wild-type measles virus is an essential component of the laboratory-based surveillance. This study describes the molecular characterization of measles virus strains isolated during 2010. METHODS Dried blood spots, urine and oral fluid samples were collected from patients with a suspected measles infection. Serological tests were performed on capillary blood, and viral detection was performed on urine and oral fluid samples through molecular assay. Positive samples were sequenced and phylogenetically analysed. RESULTS AND DISCUSSION The phylogenetic analysis showed a co-circulation of genotypes D4 and D8, and sporadic cases associated to genotypes D9 and B3. Then, molecular epidemiology of measles cases permitted to establish that D4 and D8 were the endemic genotypes in Italy during 2010.

Measles in Italy: Co‐circulation of B3 variants during 2014

In 2013, the majority of the WHO/EUR countries reported an annual incidence of >1 case per one million population indicating that the elimination target is far from being met. Thus, there is the urgent need to uncover and analyze chains of measles virus (MV) transmission with the objective to identify vulnerable groups and avoid possible routes of introduction of MV variants in the European population. The analysis of molecular epidemiology of MV B3 strains identified in 2014 has shown that four different variants co‐circulated in Italy, including the strain that caused a cruise‐line ship outbreak at the beginning of the year. J. Med. Virol. 88:1081–1085, 2016.

Genetic variability of the S segment of Toscana virus

Toscana virus (TOSV) was originally isolated in 1971 from a pool of Phlebotomus perniciosus sandflies collected in Grosseto province (Central Italy). Since its first isolation, several studies have been conducted in Italy and other Mediterranean countries in order to identify its possible animal reservoirs, spread of infection and genetic variability. Phylogenetic analysis conducted on TOSV genome demonstrated the co-circulation of two major lineages in the Mediterranean areas, TOSV A and TOSV B. This study reports the results of the genetic analysis of 32 viral strains isolated in Italy in the last 30 years from patients hospitalized with neurological disease, from sandflies and from the brain of a bat. The genetic diversity of TOSV was investigated by determining the sequences of the whole S segment. Phylogenetic analysis showed that TOSV A lineage represents the lineage circulating in Italy. Moreover, the current variability of lineage A is similar to that of lineage B.

Molecular epidemiology of measles virus in Italy during 2008

INTRODUCTION In view of the goal of measles elimination, it is of great importance to assess the circulation of wild-type measles virus (MV). Genetic analysis is indispensable to understand the epidemiology of measles. A large measles outbreak occurred in Italy in 2008, with over 4000 cases reported to the enhanced measles surveillance system introduced in 2007, 37% of which were laboratory confirmed. METHODS Urine and saliva samples were collected during 2008. A phylogenetic analysis of measles sequences was performed in order to understand the epidemiological situation of wild-type (MV) circulation in that period. RESULT AND DISCUSSION Data showed predominant circulation of the genotype D4. Genotypes A, D8, D9 and H1 were also detected in a small number of samples, probably representing imported cases.