The evidence of circulation of some viruses in a great town of Romania during the first half of 1992.

Complex serological survey performed in the town B. during the first half of 1992 emphasized an active circulation of some respiratory viruses, especially of parainfluenza type 3 and 1, influenza subtypes A(H3N2) and A(H1N1), adeno and syncytial respiratory as well as of Mycoplasma pneumoniae. Less important was the frequence of antibodies against Chlamydia psittaci, East equine, West Nile and tick-borne encephalitis as well as parainfluenza type 2 and influenza type B viruses.

[Research on arbovirus infections]. / Recherches sur les infections à arbovirus.

The author presents the results of researches done at the "Stefan S. Nicolau" Institute of Virology in Bucharest on the infections induced by arboviruses. The characteristics of three tick encephalitis virus strains (two strains isolated from Ixodes ricinus and Ixodes persulcatus ticks and one from a patient with encephalitis symptoms) are given. Most of the report is devoted to the results of serological survey conducted in a human population, in several domestic birds and mammals from some districts of Romania, as well as in migratory birds from the Danube delta, with regards to the incidence of some Toga-, Bunya- and Reoviruses.

Study on the innocuity of the hypophyseal human growth hormone.

The hypophyseal human growth hormone (hGH), a Raben type laboratory preparation, was re-evaluated as regards its innocuity for therapeutic use. Besides the usual control tests recommended by the Romanian Pharmacopoeia, the contamination of the hGH for clinical use with acute and slow viruses, was investigated taking into account the withdrawal of this hormone in many developed countries. The contamination was absent both with acute viruses as resulted from hemadsorption on cell cultures and counterimmunoelectrophoresis, and with slow viruses as observed from a two year-follow up of guinea pigs injected intracerebrally with the hGH preparation. Further, the content of the growth hormone itself as well as the contamination degree with other pituitary hormones was examined. The hGH-RIA content was 2.23 +/- 0.13 IU/mg (means +/- SEM), range: 1.38-2.80 IU/mg (1st International Standard hGH 80/505-1982). The prolactin contamination assessed by RIA was 187.34 +/- 37.66 ng/mg hGH, range: 28.44-385.20 ng (International Standard WHO: 80/541). The LH and FSH contamination as quantified by the Isocommerz (DDR) RIA kits was with two orders of magnitude lower than 10 IU-LH/IU-hGH, the upper LH contamination limit considered as acceptable. Moreover, the proportion of the large molecular forms in the lyophilized hGH preparation was investigated by polyacrylamide gel electrophoresis. Corroborating the data obtained by these control tests with our previous experience on 149 pituitary dwarfs treated with this hGH preparation during the interval 1964-1984, resulted minor risks of some dangerous side effects of hGH administration in children with growth hormone deficiency by possible contamination with pathogenic agents or with other disturbing hormones.

[Presenile dementia (Creutzfeldt-Jakob disease). Clinical and experimental data on a newly reported case]. / La démence présénile (maladie de Creutzfeldt-Jakob). Données cliniques et expérimentales sur un nouveau cas enregistré.

A newly recorded case of presenile dementia (Creutzfeldt-Jakob disease) is discussed. The disease is experimentally transmissible to guinea pigs, after a long incubation period. From a pathomorphological point of view the experimental disease in the guinea pig is characterized by spongiosis, proliferative glial reaction, disappearance of neurons and of Purkinje's cells.

[Multiple sclerosis. Risk factors]. / La sclérose multiple. Facteurs de risque.

Hypothetical risk factors in multiple sclerosis are reviewed. So far accumulated data how that the most probable of the risk factors is represented by the morbillivirus group.

Data on the experimental transmission in the guinea pig of some human chronic degenerative diseases: Creutzfeldt-Jakob and Alzheimer's disease.

Guinea pigs were inoculated intracerebrally with cerebrospinal fluid (CSF) and/or brain tissue suspensions from 8 patients with Creutzfeldt-Jakob disease (CJD) and with CSF from 2 patients with Alzheimer's disease. After a very long incubation period (over 360-420 days) a serially transmissible experimental disease appeared in the guinea pigs inoculated with CSF from 5 of the CJD patients, with either CSF or brain suspension from one CJD patient and with brain suspensions from the remaining 2 CJD patients. The disease was characterized by tremor, ataxia, convulsions and morphopathological lesions, such as spongiform change, glial hyperplasia and vacuolation of the neurons. Inoculations of CSF from the two Alzheimer's disease cases gave negative results.

Serological investigations on the presence of antibodies to tick-borne encephalitis virus in domestic animals and birds and in humans.

The presence of hemagglutination-inhibiting antibodies to tick-borne encephalitis virus was investigated in serum samples from domestic animals (217 from swine, 214 from cattle, 179 from goats and 161 from sheep) and birds (214 from geese and 171 from ducks), as well as from 511 apparently healthy subjects of a biotope with particular ornithological and entomological characteristics. The proportion of positive reactions was very low in cattle (1.4%) and goats (1.1%) and more elevated in humans (11.3%). All the serum samples from swine, sheep, geese and ducks gave negative serological results.

Some trends of research in the domain of viral neuroinfections approached in the "Stefan S. Nicolau" Institute of Virology.

The main directions of research in the field of viral neuroinfections approached during 35 years in the Institute of Virology are briefly outlined. After some considerations on terminology and on the classification of viral encephalitides, mention is made of the studies in the domain of herpes infections, rabies, meningitis, encephalitis and slow virus infections of the central nervous system (subacute sclerosing panencephalitis, multiple sclerosis, amyotrophic lateral sclerosis, Creutzfeldt-Jakob disease, etc.).

Laboratory investigations in Balkan endemic nephropathy.

Serum samples from three patients with Balkan endemic nephropathy (BEN) were inoculated intraperitoneally to guinea pigs. After a very long incubation period (58-273 days) the animals developed an experimental disease characterized by apathy, tremor, convulsions and a fatal outcome. The disease could be serially propagated, the same clinical symptoms being recorded at each of the three passages performed. The morphological features of the experimental disease included glomerular and tubular lesions and the presence of interstitial fibrous and lymphoplasmocytic reactions. Different hypotheses on the etiology of BEN are discussed.

Creutzfeldt-Jakob disease: experimental transmission in the guinea pig.

An experimental disease could be serially propagated in the guinea pig by intracerebral inoculation of cerebrospinal fluid or brain suspensions from 8 patients with Creutzfeldt-Jakob disease (CJD). The disease, characterized by tremor, ataxia and convulsions, appeared after a long incubation period (370-420 days). Microscopic lesions and electron optic features were similar to those described in human CJD and in experimental CJD in the chimpanzee.

Serological investigations concerning the presence of antibodies to arboviruses in wild birds.

Serum samples from 8 species of migratory birds (Ardea cinerea, Plegadis falcinellus, Anas querquedula, Anser albifrons, Gavia arctica, Fulica atra, Phalacrocorax carbo, Larus minutus) were tested for the presence of hemagglutination-inhibiting (HAI) antibodies to alpha- and flaviviruses. HAI antibodies to alphaviruses (eastern equine encephalitis, western equine encephalitis, Sindbis, Middelburg, Semliki Forest) ranging in titer from 1/20 to 1/160 were detected in 46 serum samples; 22 serum samples gave positive reactions (titers: 1/20 - 1/80) to flaviviruses (West Nile, Ntaya). In certain cases antibodies to several antigens could be made evident in the same serum sample. The serological results are discussed in the light of the birds' migration pattern.

Further data on experimental Creutzfeldt--Jakob disease (spongiform encephalopathy) in the guinea pig.

Intracerebral inoculation to guinea pigs of cerebrospinal fluid or brain suspensions from 6 patients with Creutzfeldt--Jakob disease was followed in 4 cases by the appearance, after a long incubation period, of a serially transmissible experimental disease. The disease was characterized by tremor, discrete ataxia and convulsions and led to a fatal outcome within several days. Microscopic lesions in the brain of guinea pigs with the experimental disease consisted in glial proliferation, spongiform change and vacuolation of neuron cytoplasm. Electron microscopy proved that the vacuoles were situated in the endoplasmic reticulum and in the cytoplasmic processes.

Endemic Balkan nephropathy, a slow virus disease?

Serum samples from patients with endemic Balkan nephropathy (EBN) were inoculated intraperitoneally to four species of laboratory animals. It was only in the guinea pig that a serially transmissible experimental disease occurred, after a long incubation period. The morphopathological features in the guinea pig were similar to those encountered in the terminal phase of human EBN. The hypothesis that EBN might be a slow virus disease is discussed.

Laboratory data on the experimental transmission of Creutzfeldt--Jakob disease in the guinea pig.

Cerebrospinal fluid samples collected from 3 patients with Creutzfeldt-Jakob disease were inoculated intracerebrally to guinea pigs. After an incubation period of 4-14 months the animals developed a serially transmissible disease, characterized by loss of appetite, loss of weight, difficulty in movement, myoclonic convulsions and a fatal outcome within several days. The microscopic lesions caused by the experimental disease consisted in glial proliferation, spongiform change and vacuolation of the cytoplasm of proximal dendritic regions.

Electron optic study of the lesions induced by Creutzfeldt--Jakob disease virus in the guinea pig.

An electron microscopic study was performed in brain sections from guinea pigs with experimental Creutzfeldt-Jakob disease. Vacuolation of the neuropil, dilatations of the endoplasmic reticulum and lipid accumulations were observed in the grey matter, while the white matter exhibited intramyelinic vacuoles.

Serological investigations into the presence of antibodies to Yaba 1--Lednice 110 virus in Romania.

Sera collected from several migratory birds of the Danube Delta, from humans and domestic birds and animals of three Romanian counties were tested by hemagglutination-inhibition reaction for the presence of antibodies to Yaba 1--Lednice 110 virus. Antibodies could be detected in only 8 of the 14 species of migratory birds included in the study, especially in wild geese and ducks.