ABSTRACT
Regulatory guidelines for production of plasma-derived products emphasize the need to document methods of viral inactivation and demonstrate the effectiveness of screening methods. Therefore, it is important to evaluate the kinetics of such processes. Togaviridae family virions may be considered as good tools for quality control of haemoderivatives, if they possess large amounts of cholesterol and saturated lipids and high structural lipid/protein ratio in their envelope composition, which give more resistance to classical treatments. The purpose of this study was to evaluate the efficiency of solvent-detergent and heat treatments adopted during the human haemoderivatives processment. Sindbis virus was used as a model for inactivation of enveloped viruses. Semi-processed human factor VIII (FVIII) product experimentally contaminated with Sindbis virus was used to test a solvent-detergent treatment with tri-N-butyl-phosphate (TNBP) and Tween 80. To evaluate thermal inactivation kinetics, lyophilized, and reconstituted samples of Sindbis virus-containing FVIII were incubated up to 30 h at 60 degrees C. The results showed that treatment with TNBP and Tween 80 reduced the infectivity of virus-contaminated FVIII in > or =5.5 log(10) and heat treatment was effective in all samples, although FVIII concentrate had reduced the rate of viral inactivation during a brief period of time.
Subject(s)
Biomedical Technology/methods , Sindbis Virus , Thromboplastin/analysis , Biological Products , Hot Temperature , Humans , Organophosphates/pharmacokinetics , Organophosphates/pharmacology , Polysorbates/pharmacology , Quality Control , Sindbis Virus/drug effects , Sindbis Virus/isolation & purification , Surface-Active Agents/pharmacology , Thromboplastin/drug effects , Virus Inactivation/drug effectsABSTRACT
A retrospective study on the prevalence of hepatitis E virus (HEV) infection was conducted in selected populations in Rio de Janeiro, Brazil. A total of 1,115 subjects were tested including 146 patients with acute Non-A Non-B Non-C (NANBNC) viral hepatitis, 65 hemodialysis patients, 93 blood donors, 102 intravenous drug users (IVDUs), 304 pregnant women, 145 individuals living in the rural area and 260 individuals living in the urban area. In order to characterize a favorable epidemiological set for enterically transmitted infection in the studied populations we also evaluated the prevalence of anti-HAV IgG (hepatitis A virus) antibodies. Specific antibodies to HEV (anti-HEV IgG) were detected by a commercial EIA and specific antibodies to HAV (anti-HAV IgG) were detected using a competitive "in house" EIA. We found a high prevalence of anti-HAV IgG in these populations, that could indicate some risk for infections transmitted via the fecal-oral route. The anti-HEV IgG prevalence among the different groups were: 2.1 percent in patients with acute NANBNC viral hepatitis, 6.2 percent in hemodialysis patients, 4.3 percent in blood donors, 11.8 percent in IVDUs, 1 percent in pregnant women, and 2.1 percent in individuals form the rural area. Among individuals living in the urban area we did not find a single positive serum sample. Our results demonstrated the presence of anti-HEV IgG in almost all studied populations; however, further studies are necessary to establish the real situation of HEV epidemiology in Rio de Janeiro, Brazil
