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Summary Background As a crossroads for bird migration between Africa and Eurasia and with its long history of human infection, Israel has been a major focus of attention during the continuing global spread of West Nile fever (WNF). This article reviews the background and reemergence of WNF in Israel; the recent epidemiology of WNF among Israelis; and the disease-control strategies being used to combat the disease. Methods Employing the comprehensive base of case data that are reported to the Ministry of Health, an epidemiological record was constructed that details the incidence and distribution of WNF cases in Israel in recent years. Results After decades of small, intermittent outbreaks, nearly 1400 cases of WNF were reported in Israel between 2000 and 2012. Incidence was consistently highest in the coastal cities, among elderly patients, and in the late summer months and early autumn. A broad range of control measures to prevent human infection has been implemented, and attention has been given to issues such as the protection of the national blood bank and the occurrence of long-term sequelae. Conclusions The reemergence of WNF in Israel is likely the result of a combination of factors including past immunity to the virus among the human population, a marked increase in awareness of WNF among physicians, and more frequent requests for the laboratory testing of suspected cases. In the absence of effective vaccine to protect humans from WNF, the best disease-control strategies include intensive vector-control measures, the continued development of techniques to forecast outbreaks, and effective public education programs that are targeted toward the high-risk elderly population.

Barkedji virus, named after the area of its first identification in Senegal, is a newly discovered flavivirus (FV), for which we propose the abbreviation BJV. In the present study, we report the first-time detection of BJV in Culex perexiguus mosquitoes in Israel in 2011 and determination of its almost complete polyprotein gene sequence. We characterized the BJV genome and defined putative mature proteins, conserved structural elements and potential enzyme motifs along the polyprotein precursor. By comparing polyproteins and individual proteins of BJV with several other FVs, a distant relationship of BJV to Nounane virus (NOUV), a recently described African FV, is demonstrated. Phylogenetic analysis of 55 selected flaviviral polyprotein gene sequences exhibits two major clusters, one made up of the classical three clades of FVs: mosquito-borne, tick-borne and those without known vectors. The other cluster exclusively contains so-called ‘insect-specific’ FVs, which do not replicate in vertebrate cells. Based on our phylogenetic analysis, BJV is related to other members of the mosquito-borne clade with yet unknown vertebrate hosts, such as NOUV, Donggang virus, Chaoyang virus and Lammi virus. However, with a maximum identity of only 54 % to NOUV, BJV represents a distinct new virus species.

To the Editor: In recent years, Aedes albopictus, a mosquito vector of dengue and chikungunya viruses, has rapidly expanded in Europe. Since 2007, the presence of viremic patients with imported cases of dengue and chikungunya virus infection has resulted in several incidences of autochthonous transmission of the viruses in Italy, France, and Croatia (1–4). A. albopictus mosquitoes have invaded Israel since 2002. A recent national survey showed wide distribution of the mosquito in Israel (5), and dengue and chikungunya virus infection are increasingly reported in travelers from Israel who return home from trips to other countries (6,7). We looked for overlap between the distribution areas of A. albopictus mosquitoes in Israel and the living areas of travelers who have returned to Israel with acute dengue or chikungunya virus infections. We discuss the possibility of autochthonous transmission of these viruses in Israel. All cases of imported, serologically proven acute dengue and chikungunya virus infection registered during 2008–2010 at the National Center for Zoonotic Viruses, Central Virological Laboratory, Israel Ministry of Health, were included in the study. For dengue diagnosis, IgM capture ELISA was run in parallel with dengue indirect IgG ELISA, according to the manufacturer’s (PANBIO, Brisbane, Australia) instructions. For chikungunya diagnosis, microchip technology (Euroimmune, Gross-Groenau, Germany) was performed to detect specific IgM and IgG antibodies. Paired acute- and convalescent-phase samples with a >4-fold increase confirmed an acute case. Laboratory diagnosis was matched to clinical observations; travel history, along with previous vaccination for yellow fever; and tickborne or Japanese encephalitis. Local infection was differentiated from imported infection by interpretation of a questionnaire that is required from treating physicians before serologic testing. Testing for West Nile virus and Sindbis virus were done to rule out cross-reactions with endemic flaviviruses and alphaviruses, respectively. Geographic distribution of A. albopictus mosquitoes in Israel during 2008–2009 was observed by monitoring the presence of eggs, larvae, and adult mosquitoes in ovitraps and by monitoring reports from municipalities and pest management professionals (5). Patients’ areas or municipalities of residence were plotted on a map describing the currently known distribution of A. albopictus mosquitoes in Israel. We evaluated the number and proportion of dengue and chikungunya patients in A. albopictus–endemic regions. During the study years, 41 and 15 patients, respectively, received diagnoses of dengue and chikungunya virus infection at the National Center for Zoonotic Viruses (Figure). Of the 41 dengue and 15 chikungunya patients, 27 (66%) and 12 (80%), respectively, lived in areas where A. albopictus mosquitoes were endemic (Figure). No autochthonous cases were reported. Figure Patients with imported dengue (black circles) or chikungunya (black triangles) virus infection living in Aedes albopictus–endemic areas of Israel, 2008–2010. Gray shading indicates known and black outline suspected A. albopictus–endemic ... The establishment of A. albopictus mosquitoes in Israel provides suitable conditions for autochthonous transmission of dengue and chikungunya viruses. Although it was traditionally regarded a secondary vector for dengue virus, A. albopictus can spread the virus. The potential risk for local outbreaks of dengue or chikungunya virus disease is dependent on the presence of viremic patients and a suitable vector (8). Recent reports emphasized the risk for autochthonous transmission of dengue, yellow fever, and chikungunya viruses in Europe. This risk is strengthened by the history of yellow fever and dengue in temperate regions. Dengue virus transmission may follow 2 general patterns: epidemic and hyperendemic dengue. Epidemic dengue transmission may occur as an isolated event when virus is introduced into a region with susceptible hosts and an adequate vector. Such events involve a single virus strain and may manifest in explosive transmission. Reported cases of autochthonous dengue in France and Croatia were presumed to be related to newly spread A. albopictus mosquitoes (2–4). An outbreak of chikungunya virus infections that occurred in Italy during the summer of 2007 involved >200 persons (1). A. albopictus mosquito spread in Hawaii was regarded as the cause of a dengue outbreak in 2001 (9), and in Florida, dengue fever was recently documented in Key West, where A. aegypti mosquitoes are established (10). In this report, we document importation of dengue and chikungunya viruses by travelers to A. albopictus–endemic areas in Israel. We show that most patients in Israel with imported dengue and chikungunya virus infection reside in A. albopictus–endemic areas of the country. The reported number of serologically proven cases probably underestimates the true extent of the diseases in Israeli travelers because underdiagnosis and underreporting are common. Both dengue and chikungunya virus infection result in viremia that may last up to 5 days, and viremic patients living in A. albopictus–endemic areas put the area population at risk for infection. In summary, we report conditions in Israel suitable for autochthonous transmission of dengue and chikungunya viruses. Although no autochthonous cases have been reported in Israel, they have been reported from other countries where A. albopictus mosquitoes are newly endemic. In Israel and other areas where this species is newly endemic, both dengue and chikungunya virus infection should be considered in the differential diagnosis of acute febrile illnesses, even when the patients do not report recent travel to tropical areas. Enhanced surveillance may be needed to prevent epidemic spread of these diseases. Consideration must be taken to isolating suspected (viremic) dengue and chikungunya patients to prevent the establishment of autochthonous transmission.

tp://dx.doi.org/10.1016/j.tmaid.20 77-8939/a 2014 Published by Elsev Sandfly (SF) viruses are arthropod-borne viruses transmitted to humans by the bite of phlebotomine sandflies. Serosurveys have indicated that the Mediterranean basin is an endemic region of SF viruses. Clinical syndromes caused by SF viruses range from a brief, self-limited febrile illness to meningoencephalitis. Here we present an unusually severe case with hemmorhagic-fever-like manifestations. A 62-years-old, previously healthy Caucasian woman was admitted to the intensive care unit (ICU) in a state of septic shock. Her symptoms began 5 days prior to admission and included: fever up to 40 C, chills, diffuse abdominal pain

There are currently no effective drugs to treat serious complications caused by WNV infection. The inhibition of WNV by the pluripotent immunomodulator AS101 [ammonium trichloro(dioxyethylene-0-0′)tellurate] was evaluated in vitro and in vivo, and its mechanism was explored. Adding AS101 to Vero cells 1 h or 5 min before infection increased cell survival from 21% to 84% and decreased plaque formation by 87% and virus yield by 2 logs. Following infection, high titer of WNV remained in the culture supernatants indicating interference with virus cell attachment. The binding of αVβ3 integrin to WNV and of Vero cells to anti-αVβ3 antibody were inhibited by AS101, suggesting that AS101 may block this cellular WNV receptor. Daily treatment of mice with AS101 starting 1 day before lethal infection with WNV resulted in 48% survival. However, treatment beginning 3 days post infection resulted only in 16% survival. Similarly, a single dose of anti-WNV IVIG three days post infection resulted in 16% survival compared to 100% if IVIG was given on the same day of infection or 1 day later. However, when mice received combined treatment with AS101 and IVIG starting 3 days post infection, an additive effect of 33% survival was observed. Our study suggests that AS101 has a potential preventive and therapeutic effect against WNV infection.

We report the isolation of West Nile (WN) virus from four patient serum samples submitted for diagnosis during an outbreak of WN fever in Israel in 2000. Sequencing and phylogenetic analysis revealed two lineages, one closely related to a 1999 New York isolate and the other to a 1999 Russian isolate.

Experimental parameters for optimization of the growth conditions of Besnoitia besnoiti endozoites in vitro are presented. A combination of Hepes-buffered McCoy and Leibovitz (ML) medium with 10% bovine serum was preferable to Eagle's Minimum Essential Medium (MEM) based on either Hank's or Earle's salts. The ML medium and a CO2 balanced gas phase significantly increased the growth rate of the parasite. Infection of Vero cells at 1 h after subcultivation resulted in higher yields of endozoites than infection of 24- or 48-h-old cells. Increased numbers of parasites (6 × 107 and 9 × 107) in the infection inoculum per Roux bottle containing Vero cells produced poor yields, while infection with 2 × 107 parasites resulted in a 250 to 300-fold increase after 6 days of cultivation with one medium change.

Summary Polyclonal bovine IgM-rheumatoid factors (IgM-RFs) were examined in sera of cattle immunized against babesiosis. An enzyme-linked immunosorbent assay (ELISA) was used enabling rapid screening of serum samples. Results obtained indicate a rise of serum IgM-RF levels with age in healthy bovines. However when animals of similar age and pertaining to the same herd were examined, levels of serum IgM-RF exhibited a wide distribution range. Mean values in 60 sera of 2 yrs old clinically healthy heifers originating from a single herd were of 452.60 ± 201.26 e. u. at 1 in 1,000 serum dilution and of 202.37 ± 137.86 e. u. at 1 in 4,000 serum dilution. In a herd where repeated vaccination of dams against babesiosis was carried out 3 to 6 weeks before delivery either with live Babesia bovis parasites or soluble antigens of in vitro grown organisms, no significant differences in mean IgM-RF values were found between revaccinated animals and a control group. Nor did the mean values of serum IgM-RF of calves born to the respective groups of dams exhibit significant differences. It thus appears that immunization of healthy cattle against this parasite does not affect mean serum IgM-RF levels.

An enzyme-linked immunoassay (ELISA) was applied to detect antibodies to A. centrale and A. marginale using homologous and heterologous antigens. The assay was compared with the indirect fluorescent antibody (IFA) test, and although a similar degree of sensitivity was obtained, the ELISA test had several advantages. Partially purified Anaplasma initial bodies used for antigen preparations contained negligible amounts of residual erythrocytic material, and did not interfere with the specificity of the ELISA. The antigenic similarity between A. marginale and A. centrale was further substantiated by cross-reactivity obtained with heterologous antigens in both ELISA and IFA tests, and antibodies produced during natural infection with A. marginale were indistinguishable in both tests from those produced following vaccination with A. centrale.

West Nile virus (WNV) caused disease outbreaks in Israel in the 1950s and the late 1970s. In 1998 an outbreak of WNV in goose farms and evidence of infection in dead migratory birds were reported. Consequently, human diagnostic services for WNV were resumed, including virus isolation, serology, and RT-PCR. Risk factors for infection were assessed by a serological survey in 1999, which revealed a seroprevalence of (a) 86% in people who had close contact with sick geese, (b) 28% in people in areas along bird migration routes, and (c) 27% in the general population. Following two fatal cases in Tel Aviv in September 1999 and one encephalitis case in the southern Eilot region, a regional serological survey was initiated there. The survey revealed two more WNV-associated acute encephalitis cases, an IgG seroprevalence of 51%, and an IgM seroprevalence of 22%. In the summer of 2000, acute cases of WN disease were identified in the central and northern parts of Israel, involving 439 people. The outbreak started in mid-August, peaked in September, and declined in October, with 29 fatal cases, primarily in the elderly. During the outbreak, diagnosis was based on IgM detection. Four virus isolates were subsequently obtained from preseroconverted frozen sera. Sequence and phylogenetic analysis of 1662 bases covering the PreM, M, and part of the E genes revealed two lineages. One lineage was closely related to a 1999 Israeli bird (gull) isolate and to a 1999 New York bird (flamingo) isolate, and the other lineage was closely related to a 1997 Romanian mosquito isolate and to a 1999 Russian human brain isolate.

Besnoitia besnoiti, a tissue cyst-forming coccidium, was cultivated in four tick cell lines from three Ixodidae genera (Boophilus, Dermacentor and Rhipicephalus). There was no appreciable difference in parasite proliferation in the various cell lines. The kinetics of multiplication during 4 days of cultivation did not differ in the four lines at 28 °C nor at 36 °C. The yield of parasites 4 days post infection was lower in tick cells than in Vero cells. In tick cell lines B. besnoiti had the tendency to change from banana shape to a round form.