Virological investigations in adults with acute pneumonia.

Virological investigations (immunofluorescence reactions and isolation attempts with pharyngeal exudate specimens, as well as serological tests) were performed in 110 adult patients with pneumonia. Viral or inframicrobial agents were involved in 70 (63.7%) of the cases, either alone (27 cases) or in association with bacteria (43 cases). Parainfluenza and adenoviruses were most frequently encountered both in the cases with mixed (viral + bacterial) and in those with strictly viral pneumonia. Mycoplasma pneumoniae accounted for 11% of the cases; the role of chlamydial and rickettsial germs was insignificant.

Stochastic model of the evolution of viral hepatitis morbidity.

Starting from the elementary epidemiological processes, the authors develop an evolution equation of the function generating the probability distribution of the number of viral hepatitis (VH) patients and susceptible subjects. Evolution equations for moments of order 1 and 2 - resulting from the equation of the generating function-are also discussed on the ground of certain simplifying hypotheses. The formulae are applied to the analysis of VH morbidity evolution in several children communities. The data on the evolution of the different moments and of the probability distributions are used from the specification of epidemiological transmissibility and susceptibility parameters.

Prevalence of antiviral antibodies in workers handling wastewater and sludge.

Serological investigations were performed between 1977-1978 with 972 serum samples from 243 subjects having either direct (group A) or sporadic (group B) occupational contact with wastewater or sludge. the control group (C) was represented by 100 persons having no contact with such material. The sera were tested against influenza, parainfluenza, adeno-, herpes, coronavirus, rickettsial and chlamydial antigens, as well as for the presence of HBsAg and anti-HBs. Statistically significant differences between group A and groups B and C were found as regards the prevalence of antibodies to adenovirus and parainfluenza virus type 1 antigens.

Detection of antibodies to alphaviruses and flaviviruses in some migratory birds of the Danube Delta.

Data are reported on the presence of antibodies to some group A(alphavirus) B(flavivirus) arboviruses in 8 species of migratory birds (Ardea cinerea, Plegadis falcinellus, Anas querquedula, Anser albifrons, Gavia arctica, Fulica atra, Larus minutes and and Phalacrocorax corbo) of the Danube Delta.

Investigations on the presence of antibodies to alphaviruses, flaviviruses, Bunyavirus and Kemerovo virus in humans and some domestic animals.

The presence of antibodies to some alphaviruses, flaviviruses, bunyaviruses and orbiviruses was studied in the sera from humans and domestic animals of biotopes "C" and "T" in the south-east of Romania. Specific antibodies were found in humans to 3 alphaviruses (eastern equine encephalitis, western equine encephalitis and Sindbis), in a very low proportion, and to 3 flaviviruses (tickborne encephalitis, West Nile and Ntaya), at a much higher percentage. Very low percentages of antibodies to Bunyavirus and Kemerovo virus were also detected. The proportion of antibodies to flaviruses (tick-borne encephalitis, West Nile and Ntaya) detected in domestic animals (sheep, cattle and swine) is much lower than that found in humans of the same biotope ("T").

Investigations on the presence of antibodies to several flaviviruses in humans and some domestic animals in a biotope with a high frequency of migratory birds.

Data are reported on the presence of HAI antibodies to several flaviviruses (tick-borne encephalitis, West Nile, and Ntaya viruses) in humans and some domestic animals in a biotope with a high frequency of migratory birds. The results obtained prove the presence in humans of specific antibodies in a proportion of 11.8% to tick-borne encephalitis and of 25.5% to West Nile and Ntaya antigens. Among domestic animals it was only possible to detect antibodies to West Nile (4.9% in sheep, 4.1% in cattle, and 12% in goats) and to Ntaya antigens (1.9% in sheep, 1.6% in cattle, 8% in goats, and 13.9% in swine).

Investigations on the presence of antibodies to several alphaviruses in humans and domestic animals of a region with elevated epidemiological potential.

The paper reports on serological results obtained by HAI tests against several alphaviruses - eastern equine encephalitis (EEE), western equine encephalitis (WEE), Chikungunya, Midlebourg, Semliki Forest, Sindbis, and Ilheus viruses - carried out in humans and some domestic animals in a region with an intensive circulation of migratory birds. It was possible to detect in human antibodies to EEE, WEE, and Sindbis viruses, but in very low proportions (1.8%, 0.4%, and 0.6%, respectively). Serological results obtained in animals were practically negative: antibodies to EEE virus were found only in one out of 93 horses investigated.

Investigations on the presence of hemagglutination-inhibiting antibodies to dengue virus in apparently healthy subjects of several counties in Romania.

The presence of hemagglutination-inhibiting (HAI) antibodies to dengue virus, types 1, 2, and 3 was studied in 1219 apparently healthy subjects of four counties in Romania. The proportion of positive reactions was of 0.40% to type 1, of 1.23% to type 2, and of 3.90% to type 3. Antibody proportion was different from one county to another.