Cristiano Fiorentini

An autochthonous case of Zika due to possible sexual transmission, Florence, Italy, 2014.

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.

Unusual Presentation of Life-Threatening Toscana Virus Meningoencephalitis

This case report describes a brother and a sister with severe meningoencephalitis caused by Toscana virus (TOSv). The clinical presentation was characterized by stiff neck, deep coma, maculopapular rash, diffuse lymphadenopathy, hepatosplenomegaly, renal involvement, tendency to bleeding, and diffuse intravascular coagulation. The boy had epididymo-orchitis. Recovery with neurologic sequelae as hydrocephalus was observed. Microbiological diagnosis was obtained by serological tests and reverse transcriptase-polymerase chain reaction. Sequencing of polymerase chain reaction products from the S and M segments was carried out. TOSv may be a causative agent in severe meningoencephalitis.

Phlebotomus-transmitted Toscana Virus Infections of the Central Nervous System: A Seven-year Experience in Tuscany

Toscana virus (TOSv) is a recently discovered Phlebotomus-transmitted human pathogen involved in acute infections of the central nervous system (CNS) occurring during the summer in natural foci in Italy. The purpose of this prospective study was to investigate the role of this virus in 170 patients with meningitis-meningoencephalitis of suspected viral origin, admitted to the Departments of Infectious Diseases at the Siena Hospital from 1990 to 1996. Infections caused by tick-borne encephalitis virus (TBEv) and TOSv or other neurotropic viruses were routinely diagnosed by means of conventional virological methods. 89 cases were attributed to TOSv, about 10% of which were Europeans on vacation in Tuscany. All of the TOSv-positive cases were observed during the summer and were residents of hilly areas in Siena and its province at an altitude not above 500 m. An increase in the number of cases was observed over the years, with a higher incidence among younger people. The clinical picture was similar to that observed in other viral infections of the CNS. Evolution was benign in all cases; in 2 subjects symptoms and signs of encephalitis were present.

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.

Toscana virus infections of the central nervous system in children: A report of 14 cases☆☆☆★

OBJECTIVE To evaluate the pathogenicity of a recently discovered arthropod-transmitted bunyavirus (Toscana virus) on the CNS in children and to provide information on the epidemiologic and clinical aspects of Toscana virus infection. STUDY DESIGN Case-series analysis of children hospitalized with clinical and cerebrospinal fluid examination compatible with a CNS disease of viral origin. METHODS Cerebrospinal fluid, acute, and convalescent sera were investigated for conventional neurotropic viruses and for Toscana and tickborne encephalitis viruses. A clinical-epidemiologic analysis was carried out on confirmed Toscana virus cases to clarify the profile of Toscana virus infection in children. RESULTS The study indicates that (1) Toscana virus has been endemic in the Siena province for at least 15 years; (2) the virus is responsible for at least 80% of acute viral infections of the CNS in children throughout the summertime; (3) the clinical signs and symptoms range from aseptic meningitis to meningoencephalitis; (4) infected children resided habitually or temporarily in rural or suburban areas of the Siena province, where ecological characteristics allow arthropods to be peridomestic in human settlements. CONCLUSIONS Toscana virus is the most common viral agent involved in acute infections of CNS in children in central Italy.

Prevalence and incidence of antibodies to Borrelia burgdorferi and to tick-borne encephalitis virus in agricultural and forestry workers from Tuscany, Italy.

The ticks Ixodes persulcatus and Ixodes ricinus are the main vectors of both Borrelia burgdorferi sensu lato and tick-borne encephalitis (TBE) virus in Eurasia. Borrelia burgdorferi is the cause of Lyme borreliosis, and TBE is a biphasic meningoencephalitis induced by an arbovirus belonging to the flavivirus family. The principal aims of the current investigation were (i) to determine the frequency of serological evidence of Borrelia burgdorferi sensu lato and TBE infections in healthy agricultural and forestry workers, (ii) to determine the incidence of seroconversion for antibodies against Borrelia burgdorferi sensu lato and TBE virus in Tuscan workers during a 1-year survey; and (iii) to assess the occupational risk for agricultural and forestry activities in a defined area (Tuscany, Italy). A total of 412 blood samples were taken from agricultural and forestry workers, and information on age, duration of employment, and history of tick bites was collected in a questionnaire to establish the risk factors for the diseases. Three hundred sixty-five blood donors from the same region served as controls. To estimate the rate of seroconversion, 176 of the agricultural and forestry workers were tested 1 year later. IgG and IgM antibodies against Borrelia burgdorferi sensu lato and TBE virus were detected in serum by an enzyme-linked immunosorbent assay and confirmed by Western blot analysis for Borrelia burgdorferi and by a test for inhibition of hemagglutination for TBE. Antibodies against Borrelia burgdorferi were more frequent among the workers than in the control group (7.8% vs. 4.9% in the IgG-IgM enzyme-linked immunosorbent assay and 7.03% vs. 3.56% in the confirmatory test). No seropositivity was observed for TBE virus. Eighteen of 176 subjects who underwent a second blood test developed specific antibodies against Borrelia burgdorferi within 1 year.

Detection of a chikungunya outbreak in Central Italy, August to September 2017

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.

A fatal case of encephalitis associated with Chikungunya virus infection

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 (1.5×108 copies/ml) in the cerebrospinal fluid 7 d after symptoms onset.

Humoral immunity in natural infection by tick-borne encephalitis virus.

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

Risk of acquiring tick-borne infections in forestry workers from Lazio, Italy

The seroprevalence of antibodies to Borrelia burgdorferi and tick-borne encephalitis (TBE) virus was evaluated in a group of forestry rangers in the Lazio region of Italy. One hundred and forty-five forestry rangers and 282 blood donors were examined by two-tiered serological tests for B. burgdorferi and TBE virus. Information on occupation, residence, tick bites, outdoor leisure activities and other risk factors was obtained. The prevalence of IgG/IgM antibodies to B. burgdorferi showed no statistical difference between the two groups, but there was a higher occurrence of IgM antibodies. There were significant differences between indoor and outdoor, urban and rural workplaces among the 145 exposed workers (χ2 test: p < 0.001), and a higher risk for outdoor rural than urban tasks was detected among the ten Western blot-tested forestry rangers positive to B. burgdorferi (χ2 test: p < 0.1). No seropositivity was observed for the TBE virus. Forestry rangers from the Lazio region did not have a higher risk of Borrelia infection than the blood donors, though an increase in the risk for outdoor tasks in a rural environment was observed.