ABSTRACT
An apparatus has been developed, constructed, and tested for conditioning unlimited quantities of finished waters for enteric virus detection.
Subject(s)
Enterovirus/isolation & purification , Water Microbiology/instrumentation , Water SupplyABSTRACT
The application of a new step for recovering poliovirus from moderately to highly turbid estuarine water by the filter virus-adsorption technique was investigated. The experiments were conducted under both (i) laboratory-based conditions (200-ml volumes) where the turbidity was controlled and (ii) simulated field conditions (15- to 100-gal volumes) where the turbidity varied depending upon the hydrology of the raw estuarine water. The new step consisted of adding Celite to the turbid water prior to sampling for virus. In the experiments, the pH of the water was first adjusted to 3.5 and then AlCl(3) was added to 0.0005 M. Celite was added to a concentration of 0.01% and mixed thoroughly. Either an HE Cox M-780 microfilter (Cox Instrument, Div. of Lynch Corp., Detroit, Mich.) or an MF-membrane filter (Millipore Corp., Bedford, Mass.) was used as the virus adsorbent. Virus was eluted from the Celite-filter complex in situ at pH 9 with 5x nutrient broth. In the laboratory-based experiments, when turbidity ranged from 5.0 to 30.0 Jackson turbidity units (JTU), virus recovery ranged from 66 to 89%. In the simulated field experiments, when the turbidity ranged from 8.5 to 80.0 JTU, virus recovery ranged from <1 to 74%, depending upon the multiplicity of virus input and the level of turbidity. The new step greatly improved the filtration-flux of turbid water and significantly reduced the premature clogging problem usually observed with microporous filters.
Subject(s)
Micropore Filters , Poliovirus/isolation & purification , Water Microbiology , Adsorption , Aluminum , Carcinoma, Squamous Cell , Cell Line , Chlorides , Humans , Hydrogen-Ion Concentration , Laryngeal Neoplasms , Methods , Poliovirus/growth & development , Seawater , Silicon Dioxide , Viral Plaque Assay , Virus CultivationABSTRACT
Mixtures of Venezuelan equine encephalomyelitis, Rift Valley fever, and chikungunya viruses may be assayed by selective immunofluorescence staining of infected cell monolayers. A multiple serum neutralization test is described for quantifying reactions of these viruses with mixtures of serum antibodies.
Subject(s)
Arboviruses/isolation & purification , Chikungunya virus/isolation & purification , Antibodies/analysis , Arboviruses/immunology , Chikungunya virus/immunologyABSTRACT
Aerosol mixtures of the psittacosis agent, yellow fever virus, and variola virus were assayed by selective immunofluorescence in conjunction with fluorescent cell counting. The aerosol behavior of each agent could be readily delineated at test conditions of 80 F (26.67 C) and three relative humidities (30, 50, or 80%). Of the three agents, variola virus exhibited the lowest biological decay. The biological decay rates of the airborne agents were not significantly affected by humidity changes.
Subject(s)
Aerosols , Chlamydia/isolation & purification , Variola virus/isolation & purification , Yellow fever virus/isolation & purification , Animals , Antibody Formation , Cell Line , Chickens , Culture Techniques , Fluoresceins , Fluorescent Antibody Technique , Haplorhini , Humidity , Microscopy, Fluorescence , RabbitsABSTRACT
The effects of three temperatures [30, 50, and 80 F (-1.11, 10, and 26.67 C)] and three relative humidities (30, 50, and 80%) on biological and physical decay rates of aerosols of yellow fever virus were investigated. Neither temperature nor relative humidity, independently or jointly, significantly affected biological or physical decay rates. The advantages of assaying yellow fever virus by the fluorescent-cell counting technique are discussed.
