Sandfly virus seroconversion associated with neurologic presentation

Objective:

To describe the clinical presentation and unique neurologic manifestations of sandfly viruses (SFVs) in the Jerusalem area.

Methods:

We identified all patients with acute seroconversion to SFV at the Hadassah-Hebrew University Medical Centers during the years 2008–2013 and retrospectively collected and analyzed the clinical and imaging data.

Results:

Nine patients (ranging from 1.5 to 85 years old) were identified. Presentation included acute neurologic disease, mostly with fever, change in consciousness and behavior, seizures, headache, meningitis, limb paresis, or myelitis. Eight patients had clinical signs of meningitis, meningoencephalitis, or encephalitis alone. Four patients had myelitis. MRI identified pathologic symmetrical changes in the basal ganglia, thalami, and other deep structures in 5 patients, and additional myelitis of the spine was noted on imaging in 3 patients. Seven patients had long-term follow-up: 4 completely recovered and 3 had remaining neurologic sequelae, among them 1 with permanent severe brain damage.

Conclusion:

Neurologic involvement associated with acute SFV infections is considered to be benign. However, in this series, all 9 patients presented with significant neurologic pathology associated with a unique finding of myelitis and symmetrical basal ganglia, thalami, or white matter involvement. Thus, acute SFV infection should be included in the differential diagnosis in febrile onset of neurologic manifestations and neuroradiologic changes.

Primary Versus Nonprimary West Nile Virus Infection: A Cohort Study

BACKGROUND

Since 2001, we have observed patients with a clinical picture consistent with West Nile virus (WNV) infection, which was defined as nonprimary infection (NPI) owing to the presence of highly elevated serum immunoglobulin G antibody titers with a high avidity index (≥ 55%), absent or low titers of serum and cerebrospinal fluid (CSF) immunoglobulin M, and occasionally positive results of WNV-specific real-time reverse-transcription polymerase chain reaction analysis of CSF and/or blood specimens.

METHODS

We investigated 124 patients with a diagnosis of primary WNV infection (PI) or NPI during 2005-2007 at Sheba Medical Center (Tel-Hashomer, Israel). Logistic regression was used to evaluate the association of variables with PI and NPI and with in-hospital mortality.

RESULTS

A total of 68 and 50 patients with PI and NPI, respectively were included; 6 patients had incomplete data. In multivariate models, NPI was significantly associated with underlying psychiatric disorders (adjusted odds ratio [aOR], 13.73; 95% confidence interval [CI], 2.28-82.56; P = .004), hospitalization during winter and spring (aOR, 8.82; 95% CI, 1.59-48.87; P = .013), and fever (aOR, 0.61; 95% CI, .39-.95; P = .031). In-hospital mortality was significantly associated with NPI (aOR, 3.86; 95% CI, 1.12-13.28; P = .032) and a higher Charlson comorbidity index (aOR, 1.37; 95% CI, 1.03-1.83; P = .032).

CONCLUSIONS

The possibility that NPI may be an emerging clinical entity with a high mortality rate must be considered seriously.

Antibodies to islet cell autoantigens, rotaviruses and/or enteroviruses in cord blood and healthy mothers in relation to the 2010-2011 winter viral seasons in Israel: a pilot study

AIMS

To determine whether antivirus and/or islet cell antibodies can be detected in healthy pregnant mothers without diabetes and/or their offspring at birth in two winter viral seasons.

METHODS

Maternal and cord blood sera from 107 healthy pregnant women were tested for islet cell autoantibodies using radioligand binding assays and for anti-rotavirus and anti-CoxB3 antibody using an enzyme-linked immunosorbent assay.

RESULTS

Glutamic acid decarboxylase (GAD)65 autoantibodies and rotavirus antibodies, present in both maternal and cord blood sera, correlated with an odds ratio of 6.89 (95% CI: 1.01-46.78). For five, 22 and 17 pregnancies, antibodies to GAD65, rotavirus and CoxB3, respectively, were detected in cord blood only and not in the corresponding maternal serum. In 10 pregnancies, rotavirus antibody titres in the cord blood exceeded those in the corresponding maternal serum by 2.5-5-fold. Increased antibody titres after the 20(th) week of gestation suggested CoxB3 infection in one of the 20 pregnancies and rotavirus in another.

CONCLUSION

The concurrent presence of GAD65 antibodies in cord blood and their mothers may indicate autoimmune damage to islet cells during gestation, possibly caused by cross-placental transmission of viral infections and/or antivirus antibodies. Cord blood antibody titres that exceed those of the corresponding maternal sample by >2.5-fold, or antibody-positive cord blood samples with antibody-negative maternal samples, may imply an active in utero immune response by the fetus.

West Nile fever in Israel: the reemergence of an endemic disease

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, a novel mosquito-borne flavivirus identified in Culex perexiguus mosquitoes, Israel, 2011

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.

Detection on four continents of dengue fever cases related to an ongoing outbreak in Luanda, Angola, March to May 2013

In April 2013, ten cases of dengue fever in travellers returning from Luanda, Angola, to five countries on four continents, were reported to the globally distributed GeoSentinel Surveillance network. Dengue virus serotype 1 was identified in two cases. The findings indicate that a major dengue outbreak is currently ongoing in Luanda. This report illustrates how cases from an emerging arboviral epidemic focus can spread internationally and highlights the risk of dissemination of a vector-borne disease into receptive areas

Capillary leakage in travelers with dengue infection: implications for pathogenesis

Dengue hemorrhagic fever is characterized by the presence of a capillary leak syndrome. Its pathogenesis is presumed to differ from that of classical dengue fever (DF) and to be associated with secondary dengue infection. Returning travelers given a diagnosis of DF were evaluated for capillary leakage with abdominal sonography. Data were compared between travelers with primary/secondary infection defined by epidemiologic and serologic parameters. A total of 12 (34.3%) of 35 patients had sonographic signs of capillary leakage. Most (85%) patients with capillary leakage had classical DF. Capillary leak was diagnosed in 32% of primary dengue cases and in 40% of secondary dengue cases (P = 0.69). The two patients given a diagnosis of dengue hemorrhagic fever had primary infections. The high prevalence of capillary leakage among travelers, most of them with primary exposure to dengue, calls into question the importance of secondary infection in causing capillary leakage in dengue infection.

The clinical response of West Nile virus neuroinvasive disease to intravenous immunoglobulin therapy

The aim of the study was to determine whether intravenous gamma globulin (IVIG) treatment is effective in patients with West Nile Virus (WNV) neuroinvasive disease. We contacted hospital based infectious disease experts in Israeli hospitals to identify patients with WNV neuroinvasive disease who were treated with IVIG. The main outcome measure was neurological response after treatment. There were 12 patients who received IVIG and four improved within 48 h. Three patients died, 6 had partial recovery, and 3 recovered completely. Eleven of the 12 patients were infected with Israeli genotypes that are highly homologous to Europe/Africa viruses. The rapid response in some patients suggests that IVIG is effective, and might be used to treat patients with WNV neuroinvasive disease with IVIG.

Surveillance of West Nile virus disease, Tel Aviv district, Israel, 2005 to 2010

We present the findings of a six-year surveillance period (2005–2010) of human West Nile virus (WNV) infection in Tel Aviv district, Israel. Initial notifications of positively identified patients received from the Central Virology Laboratory were followed by epidemiological investigations of the local district health office. During 2005–2010, 104 patients, 79 with WNV neuroinvasive and 25 with WNV non-neuroinvasive disease were reported. The median age of the patients with a neuroinvasive disease was 74 years (range: 15 to 95 years) and 53 of such patients had encephalitis, 14 had acute flaccid paralysis, and 12 had meningitis. The case-fatality rate in these patients was 8%. The average annual incidence of neuroinvasive disease during 2005–2010 was 1.08 per 100,000 population. The incidence declined by 86% steadily between 2005 and 2009 (p for trend=0.005), but increased by more than six-fold in 2010. Elderly (≥65 years) men, comprising 25 patients of whom 24 were chronically-ill, had the highest incidence of WNV encephalitis <0.001). These findings are concordant with previous data, at the national level, published in Israel and the United States. Notably, the percentage of previously healthy patients, who developed a neuroinvasive disease was the highest (37%, p=0.001) in the surveillance period in 2010.

Surveillance of West Nile Virus Disease, Tel Aviv District, Israel, 2005 to 2010

Binary file ES_Abstracts_Final_ECDC.txt matches

Mosquito vectors of West Nile Fever in Israel

West Nile fever (WNF) is endemic in Israel. In 1999, country-wide adult mosquito surveys were initiated and intensified after the 2000 country-wide outbreak of WNF in humans. In 8 consecutive yr, groups of male and female specimens of different species and from different locations were tested for infection with West Nile virus (WNV). Three species made up >87% of the total catch: Culex pipiens L. (52%), with an infection rate (IR) of 0.5; Cx. perexiguus Theobald (20%), with an IR of 2.7; and Aedes caspius Pallas (15%), with an IR of 0.6. The geographical and temporal distribution of WNV-infected mosquitoes was similar but was not parallel to the seasonal abundance of the populations. The seasonal occurrence of human cases is in correlation with the finding of WNV-positive mosquito specimens reaching a peak 1 mo later than the mosquito peak. The relative importance of the mosquito species in the epidemiology of WNF is discussed. Cx. perexiguus is considered the major vector of WNF in Israel.

Chikungunya fever in Israeli travelers returning from northwestern India

Chikungunya fever has been increasingly documented among Western travelers returning from areas with chikungunya virus transmission, which are also popular touristic sites. We describe the case of three Israeli travelers who developed fever, maculopapular rash, and long-standing arthralgias while visiting northern Indian states not known to be involved in the chikungunya fever epidemic.

Antiviral effect of The ImmunomodulatorAS101 on West Nile Virus by AlphaVBeta3 integrin inhibition (47.33)

The identification of integrin αVβ3 as a receptor for West Nile virus (WNV) in recent years, created opportunities in the development of antiviral strategist against WNV infection. The immunomodulator AS101 [ammonium trichloro (dioxyethylene 0-0′)tellurate] has an antiviral effect in vivo and in vitro. Our study aimed at determining whether AS101 has an antiviral effect against WNV and its mechanism of work. Cell viability assay for Vero cells treated with AS101 before WNV infection, revealed up to 90% survival of the treated cells. More over, plaque forming unit (PFU) assay showed 83% inhibition at WNV-infected Vero cells after AS101 treatment. Significant decrease in the concentration of viral infectious particles was observed in supernatants of Vero cells infected with WNV at high MOI (5) after AS101 addition, and the viral envelope protein (E) expression decreased in Vero cells infected with WNV (MOI=5) and treated with AS101. In supernatants collected from virus infected and AS101 treated Vero cells immediately after inoculation were more virus particles, than in not treated cells. A novel AS101 effect was seen at attachment assay were AS101 inhibited Vero cells attachment to human integrin αVβ3 specific antibody in dose dependent manner. Thus, the results presented here shows that AS101 has an antiviral effect against WNV, and suggests that AS101 prevents WNV entry to the cells by inhibiting integrin αVβ3.

Long-term Death Rates, West Nile virus epidemic, Israel, 2000

We studied the 2-year death rate of 246 adults discharged from hospital after experiencing acute West Nile Virus infection in Israel during 2000. The age- and sex-adjusted death rates were significantly higher than in the general population. This excess was greater for men. Significant adverse prognostic factors were age, male sex, diabetes mellitus, and dementia.

Stiff-person syndrome following West Nile fever

BACKGROUND

Stiff-person syndrome is a rare autoimmune disorder associated with antibodies against glutamic acid decarboxylase (GAD), the key enzyme in gamma-aminobutyric acid synthesis. In most cases, a trigger cannot be identified.

OBJECTIVE

To describe a 41-year-old man who developed stiff-person syndrome and antibodies to GAD following acute West Nile virus infection.

DESIGN

A case report and a search in GenBank for common epitopes.

RESULT

The search revealed a stretch of 12 amino acids in the NS1 protein of West Nile virus with a high degree of homology to the GAD65 region (an isoform of GAD) containing the PEVKEK motif.

CONCLUSION

Cross-reactivity between antibodies directed against West Nile virus and GAD may have contributed to the development of stiff-person syndrome in this patient.

West Nile fever in Israel 1999-2000: from geese to humans

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.

Isolation and characterization of West Nile virus from the blood of viremic patients during the 2000 outbreak in Israel

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.

West Nile fever outbreak, Israel, 2000: epidemiologic aspects

From August 1 to October 31, 2000, 417 cases of West Nile (WN) fever were serologically confirmed throughout Israel; 326 (78%) were hospitalized patients. Cases were distributed throughout the country; the highest incidence was in central Israel, the most populated part. Men and women were equally affected, and their mean age was 54+/-23.8 years (range 6 months to 95 years). Incidence per 1,000 population increased from 0.01 in the 1st decade of life to 0.87 in the 9th decade. There were 35 deaths (case-fatality rate 8.4%), all in patients >50 years of age. Age-specific case-fatality rate increased with age. Central nervous system involvement occurred in 170 (73%) of 233 hospitalized patients. The countrywide spread, number of hospitalizations, severity of the disease, and high death rate contrast with previously reported outbreaks in Israel.

Clinical characteristics of the West Nile fever outbreak, Israel, 2000

West Nile (WN) virus is endemic in Israel. The last reported outbreak had occurred in 1981. From August to October 2000, a large-scale epidemic of WN fever occurred in Israel; 417 cases were confirmed, with 326 hospitalizations. The main clinical presentations were encephalitis (57.9%), febrile disease (24.4%), and meningitis (15.9%). Within the study group, 33 (14.1%) hospitalized patients died. Mortality was higher among patients >70 years (29.3%). On multivariate regressional analysis, independent predictors of death were age >70 years (odds ratio [OR] 7.7), change in level of consciousness (OR 9.0), and anemia (OR 2.7). In contrast to prior reports, WN fever appears to be a severe illness with high rate of central nervous system involvement and a particularly grim outcome in the elderly.

Cellular proliferation potential during aging and caloric restriction in rhesus monkeys (Macaca mulatta)

Caloric restriction (CR) is the most successful method of extending both median and maximal lifespans in rodents and other short-lived species. It is not yet clear whether this method of life extension will be successful in longer-lived species, possibly including humans; however, trials in rhesus monkeys are underway. We have examined the cellular proliferative potential of cells from CR and AL (ad libitum fed) monkey skin cells using two different bioassays: colony size analysis (CSA) of dermal fibroblasts isolated and cloned directly from the skin and beta-galactosidase staining at pH 6.0 (BG-6.0) of epidermal cells in frozen sections of skin. Decreases in both proliferative markers occurred with age, but no differences were observed between CR and AL animals. Skin biopsies were obtained from AL and CR rhesus monkeys from two different aging colonies, one at the National Institute on Aging (NIA) and one at the University of Maryland-Baltimore (UMB). These biopsies were used as a source of tissue sections and cells for two biomarkers of aging assays. The CR monkeys had been maintained for 9-12 years on approximately 70% of the caloric intake of control AL animals. In the CSA studies, the fraction of small clones increased significantly and the fraction of large clones decreased significantly with increasing age in AL monkeys. The frequency of epidermal BG-6.0 staining cells increased with age in older (>22 years) AL monkeys, but most predominately in those of the UMB colony, which were somewhat heavier than the NIH AL controls. Old monkeys on CR tended to have fewer BG-6.0-positive cells relative to old AL-derived epidermis, but this effect was not significant. These results indicate that cellular proliferative potential declined with age in Macaca mulatta, but was not significantly altered by CR under these conditions. Although these experiments are consistent with an absence of effect of CR on monkey skin cell proliferative potential, we have found in previous experiments with mice that a longer duration of CR (as a fraction of total lifespan) was needed to demonstrate CR-related improvement in clone size in mice. Further studies on the now mid-aged monkeys will be needed as their age exceeds 20 years to conclusively rule out an effect of CR on proliferative potential of skin cells from these primates.

IgM rheumatoid factor in cattle immunized against babesiosis

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.

Besnoitia besnoiti: quantitative in vitro studies

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 x 10(7) and 9 x 10(7)) in the infection inoculum per Roux bottle containing Vero cells produced poor yields, while infection with 2 x 10(7) parasites resulted in a 250 to 300-fold increase after 6 days of cultivation with one medium change.

An enzyme-linked immunosorbent assay (ELISA) for the detection of antibodies to Anaplasma centrale and Anaplasma marginale

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.