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The emergence of Zika virus in the Americas has caused an increase of babies born with microcephaly or other neurological malformations. The differential diagnosis of Zika infection, particularly serological diagnosis, is an important but complex issue. In this study, we describe clinical manifestations of 94 suspected cases of congenital Zika from Bahia state, Brazil, and the results of serological tests performed on children and/or their mothers at an average of 71 days after birth. Anti‐Zika immunoglobulin M (IgM) antibodies were detected in 44.4% and in 7.1% of samples from mothers and children, respectively. Nearly all the IgM, and 92% of immunoglobulin G positive results were confirmed by neutralization test. Zika specific neutralizing antibodies were detected in as much as 90.4% of the cases. Moreover, dengue specific neutralizing antibodies were detected in 79.0% of Zika seropositive mothers. In conclusion, Zika IgM negative results should be considered with caution, due to a possible rapid loss of sensitivity after birth, while the NS1‐based Zika IgM enzyme‐linked immunosorbent assay test we have used has demonstrated to be highly specific. In a high percentage of cases, Zika specific neutralizing antibodies were detected, which are indicative of a past Zika infection, probably occurred during pregnancy in this population., Highlight In this study we have analyzed serum samples collected a mean of 71 days after birth from 94 suspected congenital Zika cases.Our results have shown a high percentage of positive neutralization test results for ZIKV, and also DENV, but low prevalence of anti‐ZIKV IgM antibodies.Our data confirm the difficulty of an accurate retrospective diagnosis of ZIKV congenital infection.

In 2017, a chikungunya outbreak in central Italy later evolved into a secondary cluster in southern Italy, providing evidence of disease emergence in new areas. Officials have taken action to raise awareness among clinicians and the general population, increase timely case detection, reduce mosquito breeding sites, and promote mosquito bite prevention.

Chikungunya virus (CHIKV) appeared for the first time in the Western Hemisphere--the French West Indies--in December of 2013. From there, the virus has spread to other Caribbean islands. Following the diagnosis of first autochthonous CHIKV cases in the Caribbean island of Saint Martin, a large outbreak is ongoing in the Americas. As of September 12, 2014, a total of 706,093 suspected and 9803 confirmed CHIKV cases have been reported in the Americas. This case study highlights the possibility of false-negative immunochromatographic CHIKV immunoglobulin M (IgM) tests and the need of confirmatory tests for suspected cases. Moreover, a greater spread of virus together with the presence of a mosquito vector (Aedes albopictus) enhances the risk of autochthonous transmission in Europe.

An autochthonous chikungunya outbreak is ongoing near Anzio, a coastal town in the province of Rome. The virus isolated from one patient and mosquitoes lacks the A226V mutation and belongs to an East Central South African strain. As of 20 September, 86 cases are laboratory-confirmed. The outbreak proximity to the capital, its late summer occurrence, and diagnostic delays, are favouring transmission. Vector control, enhanced surveillance and restricted blood donations are being implemented in affected areas.

G Venturi 1 , L Zammarchi 2 3 , C Fortuna 1 , ME Remoli 1 , E Benedetti 1 , C Fiorentini 1 , M Trotta 3 , C Rizzo 4 , A Mantella 2 , G Rezza 1 , A Bartoloni 2 3 1. Department of Infectious, Parasitic and Immune-Mediate Diseases, Istituto Superiore di Sanita, Rome, Italy 2. Clinica Malattie Infettive, Dipartimento di Medicina Sperimentale e Clinica, Universita Degli Studi di Firenze, Florence, Italy 3. SOD Malattie Infettive e Tropicali, Azienda Ospedaliero-Universitaria Caeggi, Florence, Italy 4. National Center for Epidemiology and Health Promotion, Istituto Superiore di Sanita, Rome, Italy.

We report a case of Zika virus infection imported in Florence, Italy ex-Thailand, leading to a secondary autochthonous case, probably through sexual transmission. The two cases occurred in May 2014 but were retrospectively diagnosed in 2016 on the basis of serological tests (plaque reduction neutralisation) performed on stored serum samples. Our report provides further evidence that sexual transmission of Zika virus is possible.

Tick-borne encephalitis (TBE) virus infection elicits a life-long lasting protection. However, little is known about the neutralizing antibodies titres following natural infection. In this study, subjects with past TBE disease (n = 62) were analysed for the presence and titre of anti-TBE neutralizing antibodies, and compared with a vaccinated cohort (n = 101). Neutralizing antibody titres were higher in individuals with past TBE and did not show an age-dependent decrease when compared with vaccinees.

In order to investigate the current and past activity of phlebovirus and flavivirus in Kosovo, a seroprevalence study among 200 blood donors was performed. Positive results were obtained for the phleboviruses TOSV and SFNV, and for a flavivirus of the Japanese Encephalitis group. No positive results for TBEV were observed.

In July of 2013, samples from a patient with a neurological syndrome were collected from Mantua hospital and sent to the National Reference Laboratory for Arboviruses (National Institute of Health, Rome). On the basis of the symptoms, serological and molecular assays were performed to diagnose either West Nile virus (WNV) or Toscana virus (TOSV) infection. Molecular and serological tests confirmed TOSV infection. Virus isolation was obtained from cerebrospinal fluid. A full genome sequence was determined from this TOSV strain with next-generation sequencing using Ion Torrent technology. Nucleotide and amino acidic sequences grouped phylogenetically with lineage TOSV A and showed a low genome variability.

Tick-borne encephalitis (TBE) virus is one of the most important flaviviruses associated with neurological disease in Europe. Cross-reactive antibodies elicited by different flaviviruses can make difficult the interpretation of ELISA and hemagglutination-inhibition (HI) tests for the diagnosis of TBE. Neutralization tests, which are more specific, are not in common use because they are difficult to perform and standardize. A plaque reduction neutralization test (PRNT), optimized previously in vaccinated children, was evaluated in sera from acute cases of TBE, collected for diagnostic purposes, and from healthy human population and wild ruminants, collected for serosurvey purposes. The PRNT results were compared with the results of ELISA and HI tests. In acute TBE disease, most sera were positive for IgM antibodies by ELISA and with high HI antibody titers; neutralizing antibodies were detected in 71.4% of patients, at a very low titer (1:10 NT50) in almost all cases. Seroprevalences of 8% and 6.5% for anti-TBE ELISA antibodies were found in healthy subjects and wild ruminants, respectively. Among anti-TBE positive healthy subjects, a very low 1:10 NT50 titer was detected in 17.4% of cases, while NT80 titers ranging from 1:10 to 1:80 were detected in 65.2% of cases. Among wild ruminants, 90.9% of ELISA and HI positive samples showed a positive, ≥1:10 NT80 titer. In conclusion, neutralization assays can be useful for the diagnosis and serosurveys of TBE. J. Med. Virol. 81:665–671, 2009 © 2009 Wiley-Liss, Inc.

Viruses from the Phlebovirus genus (family Bunyaviridae) are arboviruses that can be transmitted to humans by mosquitoes (Rift Valey virus) or by sandflies. In phleboviruses group we can find the etiological agents for Sandfly Fever (SF) that is spread in the Mediterranean basin, Middle East, Pakistan and India. In Portugal, the importance of phleboviruses to the Public Health is recognized because there have been detected cases of Toscana virus infection wich is responsible for severe cases of SF that involve encephalitis/meningitis. On the other hand, Phlebotomus perniciosus, one of Toscana virus vectors, is widespread in Portugal.

Background Sandfly fever virus serotype Toscana is endemic in Mediterranean countries and is a widespread public health problem as it may be associated with acute neurological diseases such as aseptic meningitis. Aim To assess whether Toscana virus infection is associated with occupational exposure. Methods During the summer of 2001, a total of 678 blood samples were taken from healthy subjects residing in Tuscany (349 agricultural and forestry workers and 329 control subjects living in the same areas). Information on age, type of job and lifestyle was collected in a questionnaire, and sera were analysed using enzyme-linked immunosorbent assay for Toscana virus-specific antibodies. Results Seropositivity to antibodies to Toscana virus was 30% in the control group and 23% in the agricultural and forestry workers (P < 0.05). Questionnaire responses suggested that, although the agricultural and forestry workers had a potentially greater continuous exposure to sandfly fever virus (outdoor activities, rural residence and at-risk lifestyle), these risk factors did not add significant information about greater susceptibility to disease. Conclusion Our findings indicate a need for better understanding of the best preventive measures to avoid the risk related to sandfly bites, especially for people who live or work in areas at risk.

The first outbreak of autochthonously transmitted Chikungunya virus (CHIKV) in Europe, which recently occurred in the province of Ravenna in north-eastern Italy has been completely controlled: the last case onset occurred on 28 September in the town of Rimini, and in October no cases were confirmed.

Vaccination against tick-borne encephalitis (TBE) virus is the measure of choice for disease control in endemic areas, as no treatment is available. In Italy, the province of Belluno is one of the most active TBE virus infection foci. In this study sera were examined from vaccinated children living in areas around Belluno in order to monitor the immune response after anti-TBE vaccination. For the assessment of neutralizing antibodies, a plaque reduction neutralization test (PRNT) was optimized and the correlation between enzyme-linked immunosorbent assay (ELISA), hemaglutination inhibition (HI), and neutralizing antibodies titers was evaluated. All children had high serum levels of TBE IgG in ELISA test after the vaccination, in agreement with previous studies. HI and PRNT titers ranged between very low and high levels. A good correlation between HI and PRNT titers, and with IgG ELISA titers, was observed. PRNT is an useful assay for monitoring protective immunity after the completion of anti-TBE vaccination. This type-specific assay is an important tool for differential diagnosis in cases where the presence of cross-reactive antibodies due to other flavivirus infections or vaccinations cannot be excluded.

Dear Sir,Arboviruses belonging to the Phlebovirus genus are a possible cause of central nervous system (CNS) infection during the summer months in several Mediterranean countries. In particular, To...

An outbreak of Chikungunya fever occurred in north-east Italy in the summer of 2007. Only 1 fatal case was observed, in an 83-y-old male hospitalized with encephalitis. Viral genome was detected at high level (1.5 x 10(8) copies/ml) in the cerebrospinal fluid 7 d after symptoms onset.

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.

An enzyme-linked immunosorbent assay (ELISA) based on the recombinant Toscana virus nucleoprotein (rN) has been developed. Its sensitivity and specificity for the detection of virus-specific immunoglobulins G and M in human sera were similar to those of the ELISA that is based on an antigen extracted from infected mouse brain and that is routinely used for serodiagnosis.

Chikungunya fever is a viral disease transmitted by Aedes spp mosquitoes. The infection is endemic in parts of Africa, South-east Asia and on the Indian sub-continent.