Whole genome sequencing and phylogenetic analysis of West Nile virus lineage 1 and lineage 2 from human cases of infection, Italy, August 2013.

A human outbreak of West Nile virus (WNV) infection caused by WNV lineage 2 is ongoing in northern Italy. Analysis of six WNV genome sequences obtained from clinical specimens demonstrated similarities with strains circulating in central Europe and Greece and the presence of unique amino acid changes that identify a new viral strain. In addition, WNV lineage 1 Livenza, responsible for a large outbreak in north-eastern Italy in 2012, was fully sequenced from a blood donor during this 2013 outbreak.

Clinical and virological findings in the ongoing outbreak of West Nile virus Livenza strain in northern Italy, July to September 2012.

In July-September 2012, one month earlier than in previous years, 13 confirmed human cases of West Nile virus infection were diagnosed in northern Italy, including five with neuroinvasive disease, three with West Nile fever, and five West Nile virus (WNV)-positive blood donors. In nine cases, the presence of the WNV lineage 1a Livenza strain, characterised in 2011, was ascertained. Symptomatic patients had prolonged viruria with high viral load.

Novel West Nile virus lineage 1a full genome sequences from human cases of infection in north-eastern Italy, 2011.

During 2008-2009, several human cases of WNV disease caused by an endemic lineage 1a strain were reported in areas surrounding the Po river in north-eastern Italy. Since 2010, cases have been recorded in nearby northern areas, where, in 2011, both lineage 1a and 2 were detected. We describe here two new WNV complete genome sequences from human cases of WNV infection occurring in 2011 in the Veneto Region. Phylogenetic analysis showed that both genome sequences belonged to lineage 1a and were related to WNV strains of the Western Mediterranean subtype. The novel WNV genomes had high nucleotide and amino acid sequence divergence from each other and from the WNV strain circulating in Italy in 2008-2009. The presence of different WNV strains in a relatively small geographical area is a novel finding with unpredictable impact on human disease that requires further investigation.

New endemic West Nile virus lineage 1a in northern Italy, July 2012.

We report here the first blood donation positive for West Nile virus (WNV) by nucleic acid amplification testing collected in north-eastern Italy in July 2012.Partial sequencing of the WNV RNA demonstrated identity with a WNV lineage 1a genome identified in the same area in 2011 and divergence from the strain responsible for the outbreak in northern Italy in 2008­09. These data indicate that WNV activity in northern Italy is occurring earlier than expected and that different WNV strains are circulating.

Human cases of West Nile Virus infection in north-eastern Italy, 15 June to 15 November 2010.

In 2010, for the third consecutive year, human cases of West Nile virus (WNV) infection, including three confirmed cases of neuroinvasive disease and three confirmed cases of West Nile fever, were identified in north-eastern Italy. While in 2008 and 2009 all human cases of WNV disease were recorded in the south of the Veneto region, cases of WNV disease in 2010 additionally occurred in two relatively small northern areas of Veneto, located outside those with WNV circulation in the previous years. WNV IgG antibody prevalence in blood donors resident in Veneto was estimated as ranging from 3.2 per 1,000 in areas not affected by cases of WNV disease to 33.3 per 1,000 in a highly affected area of the Rovigo province. No further autochthonous human cases of WNV disease were notified in Italy in 2010. The recurrence of human cases of WNV infection for the third consecutive year strongly suggests WNV has become endemic in north-eastern Italy.

Prevalence of IgM and IgG antibodies to West Nile virus among blood donors in an affected area of north-eastern Italy, summer 2009.

Following reports of West Nile neuroinvasive disease in the north-eastern area of Italy in 2009, all blood donations dating from the period between 1 August and 31 October 2009 in the Rovigo province of the Veneto region were routinely checked to exclude those with a positive nucleic acid test for West Nile virus (WNV). Only one of 5,726 blood donations was positive (17.5 per 100,000 donations; 95% confidence interval (CI): 0.4­97.3). In addition, a selection of 2,507 blood donations collected during the period from 20 July to 15 November 2009 were screened by ELISA for IgG and IgM antibodies against WNV. A positive result was received for 94 of them. The positive sera were further evaluated using immunofluorescence and plaque reduction neutralisation test (PRNT), in which only 17 sera were confirmed positive. This corresponds to a prevalence of 6.8 per 1,000 sera (95% CI: 4.0­10.9). In a case-control study that matched each of the 17 PRNT-positive sera with four negative sera with the same date of donation and same donation centre, we did not find a significant association with age and sex of the donor; donors who worked mainly outdoors were significantly more at risk to have a positive PRNT for WNV.

Genome sequence analysis of the first human West Nile virus isolated in Italy in 2009.

In 2009, six new human cases of West Nile neuroinvasive disease (WNND) were identified in Veneto region, following the six cases already reported in 2008. A human West Nile virus (WNV) isolate was obtained for the first time from an asymptomatic blood donor. Whole genome sequence of the human WNV isolate showed close phylogenetic relatedness to the Italy-1998-WNV strain and to other WNV strains recently isolated in Europe, with the new acquisition of the NS3-Thr249Pro mutation, a trait associated with avian virulence, increased virus transmission, and the occurrence of outbreaks in humans.

West Nile virus infection in Veneto region, Italy, 2008-2009.

We report here an update on human cases of West Nile virus (WNV) infection in Veneto region, northeastern Italy. In addition to two cases of WNV neuroinvasive disease notified through a surveillance programme started in September 2008, further four cases were retrospectively identified (in May 2009) by investigating patients with aseptic meningoencephalitis of unknown aetiology occurring in Veneto region in June-September 2008. All six patients had symptom onset in August-September 2008 and were resident in a wetland area close to the Po river delta in Rovigo province. Further five cases of asymptomatic WNV infection, including four residents of the same area in Rovigo, were identified in a seroprevalence study in farm workers from Veneto region. To date, no human cases have been notified in 2009.

[Epidemiology of reproductive tract infections in a symptomatic population of North-East of Italy]. / Prevalenza di agenti d'infezioni del tratto riproduttivo in una popolazione sintomatica del Nord-Est.

AIM: Reproductive tract infections (RTIs) are one of the main causes of morbidity in the world and sexually transmitted infections (STIs) can give rise to severe sequels (inflammatory pelvic disease, etc.). The epidemiology of these infections is changeable and depends on geographical and economical factors, migratory flows and social and sexual habits. This variability, along with the lack of sufficient data in literature, is a serious problem in the development of screening, prevention and therapy strategies centered on local needs. The aim of our study was to evaluate the epidemiology of reproductive tract infections in a symptomatic population of the Nord-East of Italy. METHODS: In the period January-June 2006, we investigated 207 subjects at the Microbiology and Virology Service of Padua's Hospital, 18-65 years old, males and women, Italian and foreigners. All had symptoms or personal history pointing to a possible reproductive tract infection. For female we collected vaginal and cervical swabs, and for male urethral swabs, for microscopy, the culture for Neisseria gonorrhoeae, Trichomonas vaginalis, Mycoplasma spp., other bacteria and yeasts, and for molecular assay for Chlamydia trachomatis. RESULTS: Among our population, the prevalence of Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis were respectively 6.28%, 1.93% and 3.86%. STIs were more frequent in males, among foreigners, and in patients aged 18-30 years. CONCLUSION: From the results obtained, ideas have emerged in order to arrange a qualitative and quantitative optimization of the diagnosis of RTIs, implementing diagnostic paths based on the different typologies of patients and on the local epidemiology.