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A patient with fever, and haemorrhagic symptoms was admitted to a hospital in Glasgow on 2 October 2012. Since he had returned from Afghanistan, serum samples were sent for diagnosis at the Rare and Imported Pathogens Laboratory, where a real-time reverse transcriptase-PCR diagnosis of Crimean – Congo haemorrhagic fever was made within 3 hrs after receipt of the sample. Hereafter the patient was transferred to a high-security infectious diseases unit in London but died on 6 October.

Crimean-Congo Haemorrhagic Fever (CCHF) is a severe tick-borne disease, endemic in many countries in Africa, the Middle East, Eastern Europe and Asia. There is no approved vaccine currently available against CCHF. The most promising candidate, which has previously been shown to confer protection in the small animal model, is a modified Vaccinia Ankara virus vector expressing the CCHF viral glycoprotein (MVA-GP). It has been shown that MVA-GP induces both humoral and cellular immunogenicity. In the present study, sera and T-lymphocytes were passively and adoptively transferred into recipient mice prior to challenge with CCHF virus. Results demonstrated that mediators from both arms of the immune system were required to demonstrate protective effects against lethal challenge.

Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne disease associated with a high case fatality rate and transmitted mainly by Hyalomma marginatum . The geographical distribution of H. marginatum covers most of the Western Mediterranean basin. We aimed to investigate whether CCHF virus (CCHFv) is circulating in Tunisia. Samples from unexplained acute febrile patients (n = 181) and a high risk group of humans, mainly slaughter workers (n = 38), were collected in the summer of 2014 and analyzed for exposure to CCHFv using serological tests and real-time RT-PCR. Ticks were collected from Northern and Southern Tunisia during May–June 2014 and examined for the presence of CCHFv by real-time RT-PCR. Of the 181 febrile patients, 5 showed only high titers of IgM suggesting a recent exposure to CCHFv. Among 38 slaughter workers, 2 had IgG anti-CCHFv responses yielding a seroprevalence of 5.2%. No CCHFv was detected in ticks and sera. Our results provide evidence of human exposure to CCHFv in Tunisia.

To the Editor: As an increasing number of autochthonous Zika virus infections are reported from several South America countries (1), we read with interest the report from Musso et al. on the potential sexual transmission of Zika virus (2). We report additional evidence for this potential route of transmission after identification of an imported case of infection into the United Kingdom. After an outbreak alert for Zika in French Polynesia, active screening was implemented at Public Health England (Porton Down, United Kingdom). In 2014, a 68-year-old man had onset of fever, marked lethargy, and an erythematous rash 1 week after returning from the Cook Islands. Serum samples taken 3 days into the febrile illness tested negative for dengue and chikungunya viruses by real-time reverse transcription PCR (rRT-PCR). Test results for dengue virus IgM and chikungunya virus IgM also were negative; a test result for dengue virus IgG was indeterminate. An rRT-PCR test result for Zika virus (3) was positive and indicated a crossing threshold value of 35 cycles. This low viral load, commonly observed even in the acute phase of disease (3), meant that attempts to obtain sequence data were unsuccessful. Convalescent-phase serum, urine, and semen samples were requested; only semen was positive for Zika virus by rRT-PCR, at 27 and 62 days after onset of febrile illness. These results demonstrated stronger signals than those obtained in tests of the original serum sample, with crossing threshold values of 29 and 33 cycles, respectively. Zika virus–specific plaque reduction neutralization test results were positive on convalescent-phase serum samples. Although we did not culture infectious virus from semen, our data may indicate prolonged presence of virus in semen, which in turn could indicate a prolonged potential for sexual transmission of this flavivirus. Moreover, these findings could inform decisions regarding what control methods are implemented and which specimen types are best suited for diagnostic detection.

The rapid advancement of genome technologies holds great promise for improving the quality and speed of clinical and public health laboratory investigations and for decreasing their cost. The latest generation of genome DNA sequencers can provide highly detailed and robust information on disease-causing microbes, and in the near future these technologies will be suitable for routine use in national, regional, and global public health laboratories. With additional improvements in instrumentation, these next- or third-generation sequencers are likely to replace conventional culture-based and molecular typing methods to provide point-of-care clinical diagnosis and other essential information for quicker and better treatment of patients. Provided there is free-sharing of information by all clinical and public health laboratories, these genomic tools could spawn a global system of linked databases of pathogen genomes that would ensure more efficient detection, prevention, and control of endemic, emerging, and other infectious disease outbreaks worldwide.

Crimean-Congo hemorrhagic fever (CCHF) is endemic in the Baluchistan province, Pakistan. Sporadic outbreaks of CCHF occur throughout the year especially in individuals in contact with infected livestock. Nosocomial transmission remains a risk due to difficulties in the diagnosis of CCHF and limited availability of facilities for the isolation of suspected patients. Rapid diagnosis of CCHF virus infection is required for early management of the disease and to prevent transmission. This study describes the case of a 43-year-old surgeon who contracted CCHF during a surgical procedure in Quetta, Baluchistan and who was transferred to a tertiary care facility at the Aga Khan University Hospital, Karachi within 1 week of contracting the infection. Diagnosis of CCHF was made using a rapid real-time reverse transcription polymerase chain reaction (RT-PCR) assay for CCHF viral RNA. The patient had chronic hepatitis B and hepatitis D infection for which he had previously received a liver transplant. He proceeded to develop classic hemorrhagic manifestations and succumbed to the infection 14 days post-onset of disease. There was no further nosocomial transmission of the CCHF during the hospital treatment of the surgeon. Early diagnosis of CCHF enables rapid engagement of appropriate isolation, barrier nursing and infection control measures thus preventing nosocomial transmission of the virus.

Crimean-Congo hemorrhagic fever (CCHF) is a virus transmitted predominantly by ticks. However, contact with infected body fluids or tissues can result in animal-to-human or human-to-human transmission. Numbers of CCHF cases appear to be increasing, especially in Europe. We reviewed cases admitted to a tertiary referral unit in Kosova with suspected CCHF in 2008 and 2009, and looked at a smaller number of specimens which were sent to the Health Protection Agency, Porton Down, U.K., in further detail. The clinical features of cases admitted with suspected CCHF infection were assessed in more detail, and these are the focus of this article. Between 2008 and 2009, the numbers of patients admitted for suspected CCHF infection increased. Of the samples received in Porton Down, CCHF virus was detected in urine samples, and these patients were found to have prolonged viremia. The detection of CCHF in urine, as well as the prolonged viremias seen, are important for clinicians to know, as they may have public health implications with regard to the risk of infection, as well as provide insights into the biology and pathophysiology of infection. Further studies are required regarding the pathogenesis of this virus.

Crimean-Congo hemorrhagic fever (CCHF) is a pathogenic tick-borne disease caused by a single-stranded negative-sense RNA virus classified within the Nairovirus genus of the family Bunyaviridae. Cases of CCHF have been registered in Tajikistan since the disease was first brought to medical attention in 1944. However, historical Tajik manuscripts describe the features of hemorrhagic fever associated with ticks, indicating that the disease might have been known in this region for many years before it was officially characterized. Here we review the historical context of CCHF in Tajikistan, much of which has been described over several decades in the Russian literature, and include reports of recent outbreaks in Tajikistan.

Hazara virus (HAZV) is closely related to the Crimean–Congo hemorrhagic fever virus (CCHFV). HAZV has not been reported to cause human disease; work with infectious material can be carried out at containment level (CL)-2. By contrast, CCHFV causes a haemorrhagic fever in humans and requires CL-4 facilities. A disease model of HAZV infection in mice deficient in the type I interferon receptor is reported in this study. Dose–response effects were seen with higher doses, resulting in a shorter time to death and earlier detection of viral loads in organs. The lowest dose of 10 p.f.u. was still lethal in over 50 % of the mice. Histopathological findings were identified in the liver, spleen and lymph nodes, with changes similar to a recent mouse model of CCHFV infection. The findings demonstrate that inoculation of mice with HAZV may act as a useful surrogate model for the testing of antiviral agents against CCHFV.

Recombinant nucleoprotein from Crimean-Congo Haemorrhagic Fever (CCHF) virus was successfully derived from a baculovirus expression system and purified for use in a novel enzyme-linked immunosorbent assay (ELISA) diagnostic test. Comparable tests were used for detection of IgG and IgM antibodies, thus allowing efficient detection of both antibodies in parallel. The major benefits of the assay also included removing any requirement for polyclonal sera, thus eliminating variation in preparations and allowing standardisation between laboratories. The assay was successfully tested using a panel of positive sera supplied from samples identified as being positive in Turkey, Tajikistan and Kosovo and shown to be sensitive and specific. It is envisaged that this simple diagnostic ELISA for CCHF virus infection which removes the reliance on polyclonal antibody preparations, will be accessible to a wider range of laboratories enabling them to carry out routine diagnosis. This will improve the efficiency of diagnosis and subsequent management of infected patients.

The DNA sequence of bovine microsomal cytochrome b5 has been amplified from a liver cDNA library using a polymerase chain reaction. The amplified cDNA when cloned into plasmids that support the high-level production of cytochrome b5 in E.coli leads to protein overexpression and results in cell colonies bearing a strong red colouration. Using cassette mutagenesis, truncated versions of the cytochrome b5 cDNA have been made that encode the first 90 amino acid residues (Ala1-Lys90), the first 104 amino acids (Ala1-Ser104) and the complete protein (Ala1-Asn133). The location of the overexpressed cytochrome b5 within prokaryotic cells is dependent on the overall length of the protein. Expression of the Ala-Lys90 and Ala1-Ser104 variants leads to a location in the cytoplasmic phase of the bacteria whereas the whole protein, Ala1-Asn133, is found within the bacterial membrane fraction. The last 30 residues of cytochrome b5 therefore contain all of the necessary information to insert the protein into E.coli membranes. The solubility of the Ala1-Ser104 variant permits the solution structure and stability of this protein to be measured using 1- and 2-D 1H-NMR methods and electronic spectroscopy. 1-D NMR studies show that the chemical shifts of the haem and haem ligand resonances of the Ala1-Ser104 variant exhibit only very slight perturbations to their magnetic microenvironments when compared with the tryptic fragment of ferricytochrome b5. These results indicate an arrangement of residues in the haem pocket that is very similar in both the Ala1-Ser104 variant and the tryptic fragment and by 2-D NMR it is shown that this similarity extends to the conformations of the polypeptide backbone and side chains. Electronic spectroscopy of this variant shows absorbance maxima for the Soret peaks at 423 nm (reduced) and 413 nm (oxidized). From absorbance spectra the relative thermal stabilities of the Ala1-Ser104 variant and the tryptic fragment were measured. In the oxidized state the Ala1-Ser104 variant denatures in a single cooperative transition with a midpoint temperature (Tm) of 73 degrees C that is significantly higher than that of 'tryptic' ferricytochrome b5. The reduced form of the protein shows increased transition temperatures (Tm approximately 78 degrees C) reflected in the values of delta Hm, delta Sm and delta(delta G) of 420 kJ/mol, 1096 J/mol/K and 12.38 kJ/mol respectively, estimated for this variant. The increased stability of the Ala1-Ser104 variant and other recombinant forms of cytochrome b5 is correlated with the presence of additional residues at the N- and C-termini.(ABSTRACT TRUNCATED AT 400 WORDS)

Thermally induced denaturation has been measured for both oxidised and reduced forms of the tryptic fragment of bovine microsomal cytochrome b5 using spectrophotometric methods. In the oxidised state, the tryptic fragment of cytochrome b5 (Ala7-Lys90) denatures in a single cooperative transition with a midpoint temperature (Tm) of approximately 67 degrees C (pH 7.0). The reduced form of the tryptic fragment of cytochrome b5 shows a higher transition temperature of approximately 73 degrees C at pH 7.0 and this is reflected in the values of delta Hm, delta Sm and delta(delta G) of approximately 310kJ.mol-1, 900J.mol-1.K-1 and 5 kJ.mol-1. Increased thermal stability is demonstrated for a variant protein that contains the first 90 amino acid residues of cytochrome b5. These novel increases in stability are observed in both redox states and result from the presence of six additional residues at the amino-terminus. The two forms of cytochrome b5 do not differ significantly in structure with the results suggesting that the reorganisation energy (lambda) of the variant protein, as measured indirectly from redox-linked differences in conformational stability, is small. Consequently the reported subtle differences in reactivity between variants of cytochrome b5 may result from the presence of additional N-terminal residues on the surface of the protein.

Field studies were carried out to determine whether ticks are being imported into the British Isles on migratory birds. During spring and autumn migration 2004, ticks were collected from ringed birds at 11 bird observatories and 3 inland Riparia riparia colonies. A total of 38 ticks of 4 species (Ixodes ricinus, I. frontalis, I. lividus, I. arboricola) were collected from 12 species of bird. Ticks were tested for viruses in the Flavivirus and Nairovirus genera, with no positives found. This data demonstrates that ticks are being imported into the British Isles on migratory birds with future work recommended to determine the quantity of ticks imported and to detect low prevalence pathogens.

Background In March 2005 a Chikungunya fever outbreak began on the islands of the Indian Ocean. The number of cases of this disease dramatically rose amongst these islands before affecting over a million people in India. Travellers to these regions have returned to the UK with the disease leading to a greater than 15-fold increase in the annual number of Chikungunya virus (CHIKV) sero-positive samples in 2006. Objectives A real-time RT-PCR test was developed for CHIKV and designed to detect currently circulating strains of virus as well as other genotypes. Its sensitivity was compared with an existing standard RT-PCR assay and a previously published real-time assay. Study design A real-time RT-PCR assay was optimised and evaluated using a panel of 55 clinical serum samples and a synthetic RNA transcript as a positive control. Nucleotide sequencing of part of the E1 gene of CHIKV was used to investigate the relatedness of the samples. Results The real-time RT-PCR was 10-fold more sensitive than a conventional block-based RT-PCR and could detect as low as 20 copies of RNA transcript. The assay also had 10-fold improved sensitivity in detecting the outbreak strain of virus when compared to another published TaqMan assay. Analysis of sequences from patients that had travelled to India, Mauritius or the Seychelles showed high similarity with published sequences from the Indian Ocean island of Reunion. Conclusions A sensitive and rapid real-time RT-PCR assay has been developed for CHIKV and tested against current isolates.

The complete nucleotide sequences of the small (S) and medium (M) segments of three independent strains of Crimean-Congo haemorrhagic fever (CCHF) virus isolated in Uzbekistan, Iraq and Pakistan have been determined. Partial S and M segment sequences from two additional strains and partial large segment sequences from five strains of CCHF virus have also been obtained. These data have been compiled and compared with published full-length and partial sequences of other CCHF virus strains. Analysis of virus strains for which complete and partial S and M segment sequences are available reveals that the phylogenetic grouping of some strains differ between these two segments. Data provided in this report suggest that this discrepancy is not the result of recombination, but rather the consequence of reassortment events that have occurred in some virus lineages. Although described in other genera of the Bunyaviridae family, this is the first report of segment reassortment occurring in the Nairovirus genus.

Crimean-Congo hemorrhagic fever (CCHF) is endemic in certain rural areas of Pakistan. Since the discovery of CCHF virus (CCHFV) in the country in the 1960s, there have been 13 outbreaks in addition to sporadic cases. An outbreak during 2000 coincided with the movement of sacrificial animals from rural to urban areas for the festival of Eid-ul-Azha. Diagnosis was suspected in patients with fever and thrombocytopenia, and confirmed retrospectively using immunoassays and reverse transcriptase-PCR. Patients were given platelet, plasma and red cell infusions. Management varied due to unfamiliarity with the condition and its treatment, lack of availability of diagnostic laboratory tests and limited supply of ribavirin. Inadequate antiviral treatment and late presentation probably contributed to the death of six of the eight patients. Renal failure, disseminated intravascular coagulation and persistent high-grade fever were associated with mortality. The nucleotide sequence of the small genomic RNA segment of the CCHFV isolated in this outbreak was found to be very closely related to the CCHFV strains previously isolated in Pakistan.

The assembly and budding of human immunodeficiency virus type 1 (HIV-1) at the plasma membrane are directed by the viral core protein Pr55 gag . We have analyzed whether Pr55 gag has intrinsic affinity for sphingolipid- and cholesterol-enriched raft microdomains at the plasma membrane. Pr55 gag has previously been reported to associate with Triton X-100-resistant rafts, since both intracellular membranes and virus-like Pr55 gag particles (VLPs) yield buoyant Pr55 gag complexes upon Triton X-100 extraction at cold temperatures, a phenotype that is usually considered to indicate association of a protein with rafts. However, we show here that the buoyant density of Triton X-100-treated Pr55 gag complexes cannot be taken as a proof for raft association of Pr55 gag , since lipid analyses of Triton X-100-treated VLPs demonstrated that the detergent readily solubilizes the bulk of membrane lipids from Pr55 gag . However, Pr55 gag might nevertheless be a raft-associated protein, since confocal fluorescence microscopy indicated that coalescence of GM1-positive rafts at the cell surface led to copatching of membrane-bound Pr55 gag . Furthermore, extraction of intracellular membranes or VLPs with Brij98 yielded buoyant Pr55 gag complexes of low density. Lipid analyses of Brij98-treated VLPs suggested that a large fraction of the envelope cholesterol and phospholipids was resistant to Brij98. Collectively, these results suggest that Pr55 gag localizes to membrane microdomains that are largely resistant to Brij98 but sensitive to Triton X-100, and these membrane domains provide the platform for assembly and budding of Pr55 gag VLPs.

Human papillomaviruses (HPVs) are a group of small DNA viruses associated with benign and malignant epithelial cancers of cutaneous or mucosal origin. More than 75 different types of HPV have been isolated, each type exhibiting a particular tropism for certain kinds of epithelia. Particular types of HPVs (HPV16, 18 and a few rarer types—31, 33 and 45) are suspected to be the causative agents of at least 95% of cervical cancers, the second-most frequent cancer in women worldwide. The medical importance of these pathogens has driven intensive research efforts: the genetic organization of their genomes is now solved and the functions of their genes are essentially understood. However, other areas of the HPV life cycle are not so well characterized, such as how HPV DNA is packed and unpacked, and how the virions dock onto target cells.This shortfall in understanding is mainly due to the problems associated with propagating HPVs in cell culture and the lack of an in vitro infectivity assay. Such problems are now being addressed by using a molecular quirk of HPV—its ability to self assemble into virus-like particles (VLPs). Expression of the capsid gene L1 in eukaryotic cells yields VLPs and several research groups around the world are now manipulating VLPs in conjunction with other HPV genes to answer encapsidation questions and develop infectivity assays. VLPs also feature in the design of prophylactic vaccines, and reports have indicated that such reagents can elicit effective anti-tumor immunity.Stauffer et al.1xInfectious human papillomavirus type 18 pseudovirions. Stauffer, Y. et al. J. Mol. Biol. 1998; 283: 529–536CrossRef | PubMed | Scopus (51)See all References1 now describe the use of HPV VLPs as tools for probing HPV biology, as well as their potential for interesting biotechnological spin-offs. They show that heterologous DNA can be encapsulated into VLPs merely by the co-expression of the two capsid proteins L1 and L2 in the presence of heterologous DNA. The minor protein L2 is suspected to be involved in the encapsidation process because it becomes attached to plasmid mini-chromosomes. Interestingly, encapsidation is independent of any HPV packaging signals and particles can encapsidate non-HPV sequences such as plasmids of varying size from 5.4 to 7.9 kb. Furthermore, recombinant VLPs carrying plasmids containing the puromycin resistance gene are infectious, as evidenced by the fact that they can confer puromycin resistance to a number of human cell lines. Such VLPs have great potential for delivering genetic material into target cells, as well as providing useful tools to study HPV biology.

SUMMARY Enveloped viruses mature by budding at cellular membranes. It has been generally thought that this process is driven by interactions between the viral transmembrane proteins and the internal virion components (core, capsid, or nucleocapsid). This model was particularly applicable to alphaviruses, which require both spike proteins and a nucleocapsid for budding. However, genetic studies have clearly shown that the retrovirus core protein, i.e., the Gag protein, is able to form enveloped particles by itself. Also, budding of negative-strand RNA viruses (rhabdoviruses, orthomyxoviruses, and paramyxoviruses) seems to be accomplished mainly by internal components, most probably the matrix protein, since the spike proteins are not absolutely required for budding of these viruses either. In contrast, budding of coronavirus particles can occur in the absence of the nucleocapsid and appears to require two membrane proteins only. Biochemical and structural data suggest that the proteins, which play a key role in budding, drive this process by forming a three-dimensional (cage-like) protein lattice at the surface of or within the membrane. Similarly, recent electron microscopic studies revealed that the alphavirus spike proteins are also engaged in extensive lateral interactions, forming a dense protein shell at the outer surface of the viral envelope. On the basis of these data, we propose that the budding of enveloped viruses in general is governed by lateral interactions between peripheral or integral membrane proteins. This new concept also provides answers to the question of how viral and cellular membrane proteins are sorted during budding. In addition, it has implications for the mechanism by which the virion is uncoated during virus entry.

Introduction: Chikungunya virus, a single stranded RNA Alphavirus of the family Togaviridae, is transmitted to humans by the bite of Aedes aegypti, Aedes albopictus and other mosquitoes. An epidemic starting in Reunion Islands in March 2005 spread to Southern India, affecting 1.3 million people between Oct 2005 and Oct 2006. The epidemic reached Bellary, Karnataka in southern India by Dec 2005. Methods: From Oct 2005 to Dec 2007, children admitted to the paediatric department of the Vijayanagar Institute of Medical Sciences with an acute encephalitis syndrome were prospectively studied. All children presenting to the paediatric ward were recruited if they had suspected CNS infection or acute flaccid paralysis [and] fever or history of fever in the previous 2 weeks, together with one or more of the following: meningism (neck stiffness), photophobia, severe headache meriting lumbar puncture, altered mental state, reduced consciousness, convulsions, focal neurological signs or acute flaccid paralysis. Results: 243 patients have been recruited to date. Between April and Oct 2006, 8 children had positive plasma PCR tests for Chikungunya RNA and are described in more detail. Viral RNA was also detected by PCR in the CSF of 3 of these 8. Mean age was 6 years, range 8 months to 11 years, 5 were girls. 3 children had a rash at some stage in their illness and one had conjunctivitis. Altered mental state was reported in 7, and 6 had a GCS of less than 15 at admission. One had deafness, 3 had nausea and vomiting, and 3 had meningism. 7 had seizures, amongst whom 4 had an episode of status epilepticus (seizure lasting more than 30 minutes). 3 were aphasic during their illness and 4 had extensor plantar reflexes. There were no fatalities. At discharge, 2 patients had ongoing aphasia. The remaining 4 with a reduced GCS at admission had recovered to full coma score. Sequencing information obtained from the E1 envelope gene from plasma and CSF samples confirmed that the chikungunya genomes are of the East African lineage, which appears to have caused the more severe epidemic form of illness, compared to the Asian genotype which previously circulated in India. Conclusions: Chikungunya virus causes encephalitis in children and may be found in the CSF. It can cause severe neurological disease sequelae although the extent to which these sequelae will persist is uncertain. Given frequent travel between Asia and Europe and the potential for autochtonous transmission, as has occurred in Italy, we need to be increasingly aware of global disease outbreaks. A CASE OF HYPERCALCAEMIA IN THE RETURNING

During 5 months in 2004-2005, buffalopoxvirus infection, confirmed by virus isolation and limited nucleic acid sequencing, spread between 5 burns units in Karachi, Pakistan. The outbreak was related to movement of patients between units. Control measures reduced transmission, but sporadic cases continued due to the admission of new patients with community-acquired infections.

Identification of a full length cDNA for an endogenous retrovirus of miniature swine Akiyoshi, D.E. et al. (1998) J. Virol. 72, 4503–4507 Type C retrovirus released from porcine primary peripheral blood mononuclear cells infects human cells Wilson, A.C. et al. (1998) J. Virol. 72, 3082–3087

Hepatitis B virus (HBV) is a serious health threat, causing acute and chronic hepatitis. The number of virus carriers is estimated to exceed 300 million worldwide. The acute disease is often self-limiting, but 5–10% of infections progress into chronic hepatitis, which is associated with a high risk of liver cirrhosis and, eventually, liver carcinoma. The only treatments currently available for chronic HBV infection are interferon therapy and liver transplantation. Unfortunately, the former is expensive and the latter has serious medical consequences; at best, both are only partially successful.Because of its role as a major human pathogen, HBV has been the subject of intensive study, and many features of its structure and replication are understood. This is particularly striking in light of the difficulties in culturing HBV in vitro; consequently, much of our current knowledge comes from modern techniques of molecular biology. HBV is the prototype member of the recently defined family of viruses called the Hepadnaviridae, which replicate their DNA genomes by reverse transcription of an RNA intermediate.Although immunization against HBV is possible, it is unfortunate that an effective worldwide vaccination programme will be prohibitively expensive. Thus, limiting infections by understanding the risks associated with infectious individuals is important. Classically, there has been much documentation of vertical, sexual and parenteral transmission of HBV. However, among young and pre-adolescent children, horizontal transmission without apparent parenteral exposure is a common mode of acquisition, and the basis of this route of infection has been unresolved. This problem has been addressed by Knutsson and Kidd-Ljunggren1xUrine from chronic hepatitis B virus carriers: Implications for infectivity. Knutsson, M. and Kidd-Ljunggren, K. J. Med. Virol. 2000; 60: 17–20Crossref | PubMed | Scopus (16)See all References1, who have used a sensitive polymerase chain reaction (PCR) assay to identify HBV DNA in the urine of HBV carriers. Results show the detection of HBV DNA in urine, which raises the possibility that infectious virus particles are present. Earlier research has shown that, during HBV virus assembly, a quality control mechanism ensures that only replication competent particles are secreted from infected cells. Thus, it seems plausible that urine is a potential source of HBV infection.These results indicate that a high proportion of patients infected with HBV have HBV DNA detectable by PCR in their urine. Thus, urine from all HBV carriers could harbour infectious HBV. These findings might explain the horizontal transmission of HBV among young children, and must be considered seriously in matters of hospital hygiene and the risk of nosocomial transmission.

The genomes of lentiviruses are characterized by a number of accessory genes that, in addition to the gag–pol–env make-up of basic retroviruses, are thought to provide a complex and refined level of control in the viral life cycle.A unique feature of primate immunodeficiency viruses (HIV-1, HIV-2 and SIV) is the nef gene, which encodes the largest auxiliary protein. Although Nef proteins are highly variable, they all harbour conserved proline motifs and are N-terminally myristoylated. The function of Nef is critically important in vivo and there is a strong selective pressure for its maintenance. Recently, it has been demonstrated that Nef exerts at least four distinct activities. These include: (1) the downregulation of cell-surface CD4; (2) the downregulation of class 1 major histocompatibility antigens (MHC class 1); (3) enhanced viron infectivity; and (4) the upregulation of cell-surface Fas ligand. Numerous studies also indicate that it plays a role in cellular signal transduction and activation.Evidence for the ability of Nef to modulate signalling events in human cells is strong, and functional associations with a variety of intracellular kinases including Lck and Hck have been reported. Hck is rapidly induced following macrophage activation, and this induction has been implicated in signalling events controlling phagocytosis. This paper1xInduction of activator protein 1 (AP-1) in macrophages by human immunodeficiency virus type-1 NEF is a cell type specific response that requires both Hck and MAPK signalling events. Biggs, T.E. et al. J. Mol. Biol. 1999; 290: 21–35Crossref | PubMed | Scopus (47)See all References1 investigates the potential of Nef expression to modulate intracellular signalling events in macrophages. The central finding of this work is that in macrophages, Nef can induce the transcription factor AP-1 and AP-1-responsive genes, through interaction with Hck, and signal transduction through the mitogen-activated protein kinase (MAPK) pathway. Ultimately, this not only enhances viral replication in these cells, via transactivation of the HIV-1 promoter, but also modulates the expression of cellular genes. Interestingly, at least three other viral proteins (hepatitis B virus X protein, the polyoma middle T antigen and the Epstein–Barr virus latent membrane protein-1) modulate AP-1 activity via a similar signal transduction route, suggesting the importance of AP-1 transcriptional activation in these viral infections too. In HIV-1 infected macrophages, it is possible that the increased transcriptional activity could contribute to AIDS pathogenesis, by prolonging the life of these virus-producing cells and contributing to macrophage infection of the brain, leading to AIDS dementia complex. This work highlights the importance of Nef as a therapeutic target: further analysis of the mechanisms by which Nef activates AP-1 sites might lead to the design of new anti-HIV therapies.

The ability to genetically engineer animal viruses enables their application to medical research. The development of non-retroviral RNA viruses as vectors to deliver foreign genes for vaccination and gene therapy is particularly interesting, especially the domestication of the alphavirus group. Two papers in this field have recently been published1xTwo-helper RNA system for production of recombinant Semliki Forest virus particles. Smerdou, C. and Liljestrom, P. J. Virol. 1999; 73: 1092–1098PubMedSee all References, 2xNoncytopathic Sindbis virus RNA vectors for heterologous gene expression. Agapov, E.V. et al. Proc. Natl. Acad. Sci. U. S. A. 1998; 95: 12689–12994Crossref | PubMed | Scopus (155)See all References.Alphaviruses offer several advantages as expression vectors: they have a broad host range, high levels of expression and a small genome that is easy to manipulate. Vectors based on Semliki Forest virus (SFV), Sindbis virus and Venezuelan equine encephalitis have been constructed and deliver and express their cargo efficiently. However, the generation of wild-type virus, owing to recombination between the artificial genome and a helper genome, remains a problem in many recombinant viral systems. This biosafety issue is a concern, especially if vectors are to be used in vaccine delivery, and methods have been developed to reduce this risk. In the SFV system, Smerdou and Liljestrom1xTwo-helper RNA system for production of recombinant Semliki Forest virus particles. Smerdou, C. and Liljestrom, P. J. Virol. 1999; 73: 1092–1098PubMedSee all References1 have prevented the production of wild-type virus by using two, independent helper RNAs; this system also circumvents the requirement of a viral protease and this portion of the genome has been mutated, conferring additional biosafety. Thus, at least two recombination events and one reversion are required to generate replication-competent virus particles. Extensive analysis has failed to demonstrate the presence of wild-type viruses, emphasizing the biosafety of the two-helper system.The expression strategy of alphaviruses imposes a severe burden on normal cellular biochemistry and infected cells die quickly, restricting the use of these vectors when long-term gene expression is required. However, Agapov et al.2xNoncytopathic Sindbis virus RNA vectors for heterologous gene expression. Agapov, E.V. et al. Proc. Natl. Acad. Sci. U. S. A. 1998; 95: 12689–12994Crossref | PubMed | Scopus (155)See all References2 have developed noncytotoxic Sindbis virus vectors, which produce large amounts of foreign protein, by transfecting Sindbis virus replicons that express a puromycin N-acetyltransferase into cells grown in the presence of puromycin. Cells that survive in the presence of the drug carry replicons that are noncytotoxic and express the puromycin-inactivating enzyme. Such replicons can then be engineered to express other foreign genes for long periods in a noncytotoxic manner, which could be useful in both vaccinology and in the development of gene therapy.

Mechanism of Borna disease virus entry into cells Gonzalez-Dunia, D. et al . (1998) J. Virol . 72, 783–788

Crimean-Congo haemorrhagic fever (CCHF) is a pathogenic and often fatal arboviral disease with a distribution spanning large areas of Africa, Europe and Asia. The causative agent is a negative-sense single-stranded RNA virus classified within the Nairovirus genus of the Bunyaviridae family.Cases of CCHF have been officially recorded in Kazakhstan since the disease was first officially reported in modern medicine. Serological surveillance of human and animal populations provide evidence that the virus was perpetually circulating in a local enzoonotic cycle involving mammals, ticks and humans in the southern regions of the country. Most cases of human disease were associated with agricultural professions such as farming, shepherding and fruit-picking; the typical route of infection was via tick-bite although several cases of contact transmission associated with caring for sick patients have been documented.In total, 704 confirmed human cases of CCHF have been registered in Kazakhstan from 1948-2013 with an overall case fatality rate of 14.8% for cases with a documented outcome.The southern regions of Kazakhstan should be considered endemic for CCHF with cases reported from these territories on an annual basis. Modern diagnostic technologies allow for rapid clinical diagnosis and for surveillance studies to monitor for potential expansion in known risk areas.

Botanical, mycological, zoological, and prokaryotic species names follow the Linnaean format, consisting of an italicized Latinized binomen with a capitalized genus name and a lower case species epithet (e.g., Homo sapiens). Virus species names, however, do not follow a uniform format, and, even when binomial, are not Linnaean in style. In this thought exercise, we attempted toconvert all currently official names ofspecies included in the viru sfamily Arenaviridae and the virus order Mononegavirales to Linnaean binomials, and to identify and address associated challenges and concerns. Surprisingly, this endeavor was not as complicated or time-consuming as even the authors of this article expected when conceiving the experiment., La lista completa de autores que integran el documento puede consultarse en el archivo, Instituto de Biotecnologia y Biologia Molecular

Crimean–Congo haemorrhagic fever virus (CCHFV) is the medically most important member of the rapidly expanding bunyaviral family Nairoviridae. Traditionally, CCHFV isolates have been assigned to six distinct genotypes. Here, the International Committee on Taxonomy of Viruses (ICTV) Nairoviridae Study Group outlines the reasons for the recent decision to re-classify genogroup VI (aka Europe-2 or AP-92-like) as a distinct virus, Aigai virus (AIGV).

In light of the recent outbreak of Ebola virus (EBOV) disease in West Africa, there have been renewed efforts to search for effective antiviral countermeasures. A range of compounds currently available with broad antimicrobial activity have been tested for activity against EBOV. Using live EBOV, eighteen candidate compounds were screened for antiviral activity in vitro. The compounds were selected on a rational basis because their mechanisms of action suggested that they had the potential to disrupt EBOV entry, replication or exit from cells or because they had displayed some antiviral activity against EBOV in previous tests. Nine compounds caused no reduction in viral replication despite cells remaining healthy, so they were excluded from further analysis (zidovudine; didanosine; stavudine; abacavir sulphate; entecavir; JB1a; Aimspro; celgosivir; and castanospermine). A second screen of the remaining compounds and the feasibility of appropriateness for in vivo testing removed six further compounds (ouabain; omeprazole; esomeprazole; Gleevec; D-LANA-14; and Tasigna). The three most promising compounds (17-DMAG; BGB324; and NCK-8) were further screened for in vivo activity in the guinea pig model of EBOV disease. Two of the compounds, BGB324 and NCK-8, showed some effect against lethal infection in vivo at the concentrations tested, which warrants further investigation. Further, these data add to the body of knowledge on the antiviral activities of multiple compounds against EBOV and indicate that the scientific community should invest more effort into the development of novel and specific antiviral compounds to treat Ebola virus disease.

In February 2019, following the annual taxon ratification vote, the order Bunyavirales was amended by creation of two new families, four new subfamilies, 11 new genera and 77 new species, merging of two species, and deletion of one species. This article presents the updated taxonomy of the order Bunyavirales now accepted by the International Committee on Taxonomy of Viruses (ICTV)., La lista completa de autores puede verse al final del archivo asociado., Instituto de Biotecnologia y Biologia Molecular

In February 2019, following the annual taxon ratification vote, the order Mononegavirales was amended by the addition of four new subfamilies and 12 new genera and the creation of 28 novel species. This article presents the updated taxonomy of the order Mononegavirales as now accepted by the International Committee on Taxonomy of Viruses (ICTV). Made available in DSpace on 2019-10-26T00:34:54Z (GMT). No. of bitstreams: 1 Amarasinghe2019ArticleTaxonomyOfTheOrderMononegavira.pdf: 805549 bytes, checksum: 42865c9b05c3114e0f275d21bed7e4a3 (MD5) Previous issue date: 2019