Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne viral disease of humans that affects a wide geographic area of Africa and Eurasia, including Turkey, Iran, Pakistan, Afghanistan and Russia. Since the first detection of CCHF cases in Turkey in 2002, more than 9700 patients have been reported, with an overall mortality rate just under 5%. This article assesses the present epidemiological situation of CCHF in Turkey, with an updated literature review, describes national practices and summarizes lessons learned in preparation for future outbreaks.
Peptides corresponding to the N- and C-extremities of the adenovirus 2 fibre polypeptide were synthesized, coupled to tetanus toxoid and injected into rabbits. Two sera were obtained: the anti-NTT serum and the anti-CTT serum. These sera and an anti-native-fibre serum were used to study fragments generated by hydrochloric acid cleavage of the fibre. The 44-Kd fragment corresponding to the 2/3 N-terminal part of the molecule retained its antigenic reactivity. This is consistent with a shaft structure for this part of the fibre. The anti-peptide sera were used to orientate the fibre, i.e., to determine the site of anchorage of this protein in the penton base. First, immunorevelation of blots of enzymatic digests of native or dissociated penton suggested that the N-extremity of the fibre was involved in the assembly of this protein in the penton base. Second, attempts were made to determine the accessibility of the fibre ends in the penton structure by ELISA assays and by immunorevelation of penton in Western blots. The results agreed with the proposed orientation derived from study of the enzymatic digests. Since the 2 anti-peptide sera and the peptides were unable to affect viral adsorption, it was not possible to determine how the fibre is orientated with respect to the cell receptor. However, the anti-peptide sera were found to inhibit viral production slightly.
A cohort of 111 children born in Bangui (Central African Republic) was followed from birth to two years of age for rotavirus infections by biweekly stool investigations until six months of age, as well as at each diarrhoeic episode. Thirty-eight children (34.2%) exhibited at least one rotavirus infection by the age of 6 months. Thirty children (27%) presented with rotavirus-associated diarrhoea before 2 years of age. Until the children reached the age of 12 months, rotavirus was identified significantly more frequently in diarrhoeic stools than in non-diarrhoeic stools (p less than 0.001). A low diversity of characterized rotavirus strains was found; only two electrophoretypes were identified, and 91% of the strains belonged to subgroup II, serotype 1, with no special strain identified in newborns. A total of 38 children had a rotavirus infection before the age of six months, while 73 did not: only 2.6% of the first group had diarrhoea associated with rotavirus between 6 and 24 months, versus 20.5% in the second group (p less than 0.05). In two-thirds of the cases of infection, the presence of rotavirus in stools was detected only once; repetitive isolations were more frequent in diarrhoeic than in asymptomatic infections. The isolation rate of rotavirus in the general populations was found to be very low (0.2%).
The growth cycle of influenza virus strain FPV, Ulster 73, was altered by treatment of LLC-MK2 cells with diamidinophenylindole. Viral protein synthesis was restricted to the early pattern of virus multiplication, and post-treatment experiments showed the ability of the drug to block virus replication until the 4th hour p.i. Drug addition (followed by removal) revealed the inhibition of synthesis of late viral products, and especially of membrane protein. Kinetic studies on the production of viral RNA indicated a decrease in the synthesis of late virus-induced RNA species, suggesting that the target of DAPI is probably the late transcription of the virus genome. The nonpermissive condition mediated by the drug could represent a suitable model to study cellular intervention during viral growth.
Epidemiological data were recorded and blood samples were obtained from a group of 297 individuals from Luxembourg who had been in contact with rabies-infected or-suspected animals from 1979 to 1985, and who had been vaccinated with a complete course of HDCS rabies vaccine.
Specific monoclonal antibodies (mAb) were prepared against a rabies-related lyssavirus, Mokola virus. A strain isolated in the Central African Republic, Mok-3, was used as immunogen. After 3 fusions more than 90 hybridoma cultures secreting mAb were identified. According to their different patterns of reactivity against rabies and rabies-related viruses, 61 ascites fluids were obtained. The antibody class was IgM for 2 of them and IgG for 59. They were specific for one of the 4 major viral proteins, as determined by immunofluorescence, neutralization and immunoblotting tests. Their patterns of reactivity were determined against 6 different strains of rabies-related viruses: Lagos-bat virus from Nigeria (Lag-1) and the Central African Republic (Lag-2), Duvenhage virus from the Republic of South Africa (Duv-1) and Federal Republic of Germany (Duv-3), Mokola virus from Nigeria (Mok-1) and Cameroon (Mok-2) and a fixed strain of rabies virus, the challenge virus strain (CVS). According to their reactivities with these strains and the pattern of fluorescence, the mAb were classified into 11 different groups with intracytoplasmic fluorescence and 7 groups with cell surface fluorescence. A differential diagnosis of these lyssaviruses is possible in tissue culture using some of these mAb.
Cinq souches de virus Congo-Crimée de la fièvre hémorragique ont été isolées à partir de lots de tiques Boophilus microplus, récoltées sur dépouilles de bœuf aux abattoirs de Tananarive en 1985. Ces souches représentent les premiers isolements de virus Congo-CHF, ainsi que les premiers isolements viraux à partir de tiques, à Madagascar.
La fréquence relative des sous-groupes de rotavirus humains a été étudiée en relation avec l'électrophorétype de 268 rotavirus trouvés dans les selles d'enfants japonais atteints de gastroentérite aigu entre janvier 1986 et juin 1987. La quasi-totalité des échantillons (265/268, 99%) contient des rotavirus du sous-groupe I avec un modèle «courtå (5%) ou du sous-groupe II avec un modèle «longå (94%). Récemment nous avions mis en évidence un nouveau rotavirus du sous-groupe I (sérotype 3) avec un ARN de modèle «longå (AU-1) et cette souche a été considérérée comme étant un rotavirus animal transmis à un humain. Dans cette étude nous avons isolé une seconde souche (AU228) qui a ces nouvelles caractéristiques. La souche AU228 isolée 5 ans après la découverte de la souche AU-1, a un électrophorétype semblable mais distinct de celui de la souche AU-1. De telles souches pourraient procurer une piste pour l'élucidation des interactions possibles entre les rotavirus humains et animaux.
Eighteen phages were studied by electron microscopy. They belonged to eight morphotypes representing the Myoviridae, Siphoviridae and Podoviridae families of tailed phages. Twelve phages were members of known species and six phages belonged to three new species. Results correlated closely with serological and DNA-DNA hybridization data. Induced and non-induced propagating bacteria were investigated for lysogeny. All strains produced R-type pyocins, phage-like particles or inhibitory reactions. The identity of typing phages should be controlled periodically.
We studied the binding of Junin virus (Arenaviridae) glycoproteins, G1 and G2, to two insolubilized lectins. The results showed that mannose, N-acetyl-glucosamine and galactose residues were exposed on G2, while only the latter predominated on G1. Heterogeneity of carbohydrate chains was found in G2, the only glycoprotein that was iodinated by the lactoperoxidase method.
Rotavirus antigen was detected by ELISA or latex technique in faecal specimens of 64 (20%) out of 327 children hospitalized with acute diarrhoeal disease during a 12-month period in Casablanca, Morocco. The rotaviral diarrhoeas were more frequent in autumn and winter, but more geographically limited during these seasons. Nine different electrophoretypes (A-I) were observed in 38 of the rotavirus-positive samples containing sufficient viral RNA to give a visible electrophoretic pattern. Two ≪long≫ types, A and B, accounted for 74% of all rotaviruses identified. Over the one-year period. a clear shift in the predominant electrophoretype was observed between the autumn-winter (type A) and summer period (type B). Six additional electrophoretypes co-circulated in association with type A, whereas only one case of type E was recognized during the summer in association with type-B outbreak. Vomiting and severe dehydration were more prevalent in the rotavirus antigen-positive children and, although not statistically proven, in the electrophoretype A group.
A total of 1,715 randomly selected sheep and goat sera from Senegal were tested for antibodies against Rift Valley fever virus using an enzyme-linked immunosorbent assay. The results showed that Rift Valley fever is enzootic. The prevalence is highly heterogeneous, depending on the aera. Sheep and goats expressed comparable antibody prevalence, suggesting that both are involved equally in the virus cycle.
Sequences encoding the N protein of the bovine enteritic coronavirus-F15 strain (BECV-F15) have been cloned in PBR322 plasmid using cDNA produced by priming with oligo-dT on purified viral genomic RNA. Some 265 insert-containing clones were studied. Hybridization of these inserts with poly(A)+ RNA extracted from infected cells led to the conclusion that they were located at the 3′-end of the genome. After subcloning in M13 phage DNA, clones were sequenced by the Sanger technique. A 1,710-nucleotide sequence corresponding to the gene coding for the viral N-protein was established. It shows 2 overlapping open reading frames (ORF). The 3′-non-coding end of the gene has an 8-nucleotide sequence in common with the homologous genome areas of MHV, TGE and IBV viruses. This sequence may represent the polymerase RNA binding site. An upstream sequence surrounding the first AUG of the smaller ORF corresponds to a potentially functional initiation codon. The sequence of the primary translation product deduced from the DNA sequence predicts a polypeptide of 207 amino acids (22.9 Kd) with a high leucine (19.8%) content, possessing a hydrophobic N-terminal end. The larger ORF has a coding capacity of 448 amino acids (49.4 Kd), corresponding to the N-protein molecular weight. The deduced protein possesses 43 serine residues (9.6% of the total amino acid content) which may be phosporylated and involved in N-protein/RNA binding. N-protein also has 5 regions with a high basic amino acid content. One of them is also serine-rich and has a strong homology site with MHV, TGE and IBV viruses. In the first part of the N-terminal, a 12-amino-acid sequence (PRWYFYYLGTGP) is highly conserved for BECV-F15, JHM, TGE and IBV viruses. BCV Mebus strain and BECV-F15 have only minor differences in their N-protein sequence. Nous avons cloné l'ARN génomique du coronavirus entéritique bovin F15 (BECV-F15), dans le plasmide PBR322 après avoir préparé le cDNA correspondant à l'aide d'une amorce oligo-dT: 265 clones ont été étudiés. Leur hybridation avec les ARN poly(A)+ extraits des cellules infectées nous a permis de les localiser à l'extrémité 3′-terminale du génome. Ces clones ont été séquencés par la technique de Sanger, après sous-clonage dans l'ADN du phage M13. Nous avons déterminé une séquence de 1.710 nucléotides correspondant au gène codant pour la protéine N virale. Elle présente deux cadres ouverts de lecture (ORF) chevauchants. On observe à l'extrémité 3′-terminale non codante du génome une séquence de 8 nucléotides observée également dans la région homologue des virus MHV, GET et IBV. Cette séquence pourrait être le site de fixation de l'ARN polymérase. Le premier AUG du plus petit ORF possède en amont une séquence nucléotidique qui en fait un site d'initiation potentiellement fonctionnel. La séquence du produit primaire de traduction que l'on en déduit est un polypeptide de 207 acides aminés (22,9 Kd) à haute teneur en leucine (19,8%) ayant une extrémité N-terminale hydrophobe. Le plus grand ORF a une capacité de codage de 448 acides aminés (49,4 Kd), correspondant à la masse moléculaire de la protéine N. La protéine déduite contient 43 résidus sérine (9,6% des acides aminés), qui peuvent être phosphorylés et impliqués dans la liaison entre la protéine N et l'ARN génomique. Cette protéine présente également 5 régions fortement basiques, et l'une d'entre elles est également riche en sérine et a une forte homologie de séquence avec la région homologue des protéines N des virus MHV, GET et IBV. En outre, la première partie de l'extrémité N-terminale montre un enchaînement de 12 acides aminés (PRWYFYYLGTGP) très conservé entre ces quatre même virus. Les séquences des protéines N de la souche Mebus du BCV et du BECV-F15 ne présentent que des différences mineures.
Dans un lot de 198 sérums choisis au hasard, les anticorps anti-HIV-1 ont été recherchés à l'aide de la méthode d'agglutination. Les résultats sont comparables aux résultats obtenus par ELISA, par le test indirect d'immuno-fluorescence et par le «Western blotå.
