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A Boudreault

Publications and source records attributed to A Boudreault.

At least 37 records · Page 2Linked to original sources
PubMed1980

[Antigenic characterization of influenza A virus isolated from birds captured in Ontario, Quebec, and the maritime provinces during the 1977 season].

A total of 145 influenza A viruses were isolated from ducks, geese and passerine birds in Ontario, Québec and the Maritimes in July-August 1977. Antigenic characterization of these isolates included five hemagglutinin (Hsw1, Hav4, Hav5, Hav6, Hav7) and five neuraminidase subtypes (N1, N2, Neq1, Neq2, Nav1) in nine different combinations; one combination Hav7 Neq1 had not been previously reported. The majority of these viruses were Hsw1 N1, antigenically related to influenza viruses in pigs and humans. This large reservoir of influenza A viruses circulating in ducks may well be involved in the appearance of new viruses in other species, including humans.

Animal Population Groups↗
PubMed1979

Influenza viruses in birds: rapid identification by counterimmunoelectrophoresis.

Counterimmunoelectrophoresis with an antiserum raised in rabbits against the M protein of the avian N virus proved to be particularly useful for large-scale identification of influenza A virus isolates. Of a total of 231 hemagglutinating agents isolated from 1,656 rectal swabs collected from shore and open-country birds, 158 could be identified as influenza A viruses by counterimmunoelectrophoresis, and 75 were serologically related to Newcastle disease virus by hemagglutination inhibition with an antiserum to Newcastle disease virus. Two isolates contained a mixture of influenza A virus and Newcastle disease virus; although the Newcastle disease virus virus particles outnumbered the influenza A virus particles in a ratio of 1,000:1, as seen by electron microscopy, the latter could be readily detected by counterimmunoelectrophoresis. This type of assay appears to be of potential use for epidemiological surveillance of influenza virus isolated from humans and animals. It combines specificity, sensitivity, and simplicity.

Animals↗
PubMed1979

Live influenza vaccine: screening of attenuated virus strains by a 50% ciliary activity inhibition test in organ cultures of ferret trachea.

This study of three live attenuated inhibitor-resistant influenza vaccines showed that these preparations are usually antigenic and that they caused no significant reactions when characterized by an index of attenuation equal to or slightly better than 1.0 arbitrarily attributed to the 'reference' attenuated A/Hong Kong/68 strain of Beare and Bynoe. This index, measured in vitro on ferret tracheal rings, is expressed as the ratio of the time required for ciliary activity inhibition of 50% of the rings by the tested candidate vaccine strain and the 'reference' attenuated strain. Induction of heterologous antibodies was also observed. Oral administration of underattenuated perparations did not cause the severe reactions which were observed when the same vaccine was administered intranasally.

Adolescent↗
PubMed1977

Small-scale trial of live-attenuated influenza vaccine (A/Hong Kong/68).

Seventy-one men who were given live-attenuated A/Hong Kong/68 (H3N2) influenza vaccine during November 1973, and 34 men given placebo were examined for changes in antibody level. Overall, 12 of the 71 men (17%) given the vaccine showed a fourfold rise in haemagglutination-inhibition (HI) antibody titre after 14 days. No such rises were seen in the 34 men given placebo. However, 10 of the men showing a fourfold rise were from 19 who had no detectable HI antibody to this virus before vaccination, representing a conversion rate of 53%. The other two had a HI titre of 1/10 before vaccination. The absence of antibody response, at 14 days, in those with an HI titre of 1/20 or greater may indicated that this represents a protective level against infection. However, the vaccine virus was probably overattenuated and may have constituted a weaker challenge than might occur with a wild strain. No influenza virus was isolated from either group in the week after vaccination and no evidence of transmission to the placebo group was seen. Mild symptoms, chills, muscle pain, and stiffness were more frequently seen in the 12 persons showing a fourfold rise in antibody than in the rest of the volunteers.

Administration, Intranasal↗
PubMed1976

Effect of anti-mouse macrophage serum on murine cytomegalovirus infection.

Rabbit anti-mouse macrophage serum (AMS) was used to study the role played by macrophages against murine cytomegalovirus infection. Treatment of mice with AMS enhanced morbidity and mortality following virus infection. These results are discussed in relation to the role of macrophages against virus infections.

Adrenal Glands↗
PubMed1976

Immunization of man and animals against influenza by oral and intranasal routes.

Live human and equine influenza virus strains modified by serial passage on allantois-on-shell system (AOS) in the presence of normal horse serum were administered orally or intranasally to volunteers or horses. Mostly mild clinical short-lasting reactions, replication in nasal mucosae, transmission to placebo recipients and significant local or circulating antibody rises were observed following administration to volunteers of strains modified by five or less serial passages on AOS in the presence of normal horse serum (NHS). Milder clinical reactions, no replication, no viral transmission and lower immunogenicity were observed when up to ten serial passages on AOS+ NHS were carried out. Similar results were observed in horses and colts. Heavy shedding of A/Eq-2 strain following the challenge was observed in placebo recipients. Colts immunized intranasally were completely protected while 33% of those immunized orally shedded small quantities of A/Eq-1 and A/Eq-2 viruses. However, a sharp rise of local antibodies against both strains was measured two days after the challenge in the three groups.

Administration, Intranasal↗
PubMed1974

Lesions of the central nervous system induced in nonhuman primates by live influenza viruses.

Intracerebral and intraspinal inoculations of non-neuropathic and neuropathic strains of influenza virus into rhesus, patas and cercopithecus monkeys resulted in an acute focal ependymitis, choroiditis and meningitis followed by focal ependymal denuding without parenchymal involvement. Aqueductal stenosis and moderate hydrocephalus developed in two animals as sequelae of ependymal cell loss.

Animals↗
PubMed1973

Trials of aqueous killed influenza vaccine in Canada, 1968-69.

The appearance of the pandemic A/Hong Kong/1/68 (H3N2) influenzavirus strain provided an opportunity for a clinical field trial of influenza vaccines in Canada during the winter of 1968-69. As by November 1968 there were reports of influenza B activity and as supplies of A2/HK/68 vaccines were limited, it was decided to make a series of strictly randomized double-blind trials comparing A2/HK/68 vaccines not only with B/Mass/66 vaccines but also with a bivalent vaccine that was already in production and contained B/Mass/66 and A2/Mtl/68, the latter a strain isolated in Canada during January 1968. In 4 trials, a total of 13 729 military personnel and 4 795 primary schoolchildren were vaccinated. Reported vaccine reactions were less than 0.1% with zonally-purified vaccines and 2.6% with the "standard" aqueous killed bivalent vaccine. Three children had serious reactions. Surveillance detected an outbreak of influenza in the first two trials on the military. The 3 vaccines containing A2 strains gave similar clinical protection conservatively estimated at 42-55% but probably about 80%. The effectiveness of the A2/Mtl/68 vaccine, which was in production before the Hong Kong variant had been isolated, was unexpected. In the absence of a vaccine specific to a new pandemic strain, it should not be assumed that a vaccine made from another recent strain could not be useful.

Canada↗