The sensitivity of an enzyme-linked immunosorbent assay (ELISA) for the detection of antibody to influenza B virus was compared with that of the hemagglutination inhibition test on acute- and convalescence-phase sera obtained from adults and children infected with influenza B virus. Two whole virus, tissue culture-grown antigen preparations were used in the ELISA, influenza B/West Virginia/81 a...

The hemagglutination inhibition test is commonly used for the identification of newly isolated influenza viruses. In this laboratory several difficulties frequently were encountered in typing these new strains after primary isolation by means of this technique. These drawbacks were: (1) Some newly isolated strains are susceptible to nonspecific inhibitors of hemagglutination (Francis, Salk, and...

A simple hemagglutination inhibition (HI) test for the serological diagnosis of toxoplasmosis has been developed and evaluated. A total of 84 human and 120 mouse serum samples were tested by the newly developed HI test and compared with an immunoglobulin G-indirect fluorescent antibody test. Statistical analysis of serum titers obtained by using the HI test and the immunoglobulin G-indirect flu...

The passive hemagglutination test for antibodies against the enterobacterial common antigen (ECA) of Kunin was standardized for diagnostic purposes. Human erythrocytes were coated with a soluble ECA+ preparation from Salmonella typhimurium or, as specificity controls, with a similar ECA- preparation from congenic ECA-negative bacteria with saline, and the hemagglutination assay was performed on...

Results These are presented in table 1. Owing to the unavailability of the Treponema pallidum haemagglutination assay (TPHA) reagents at certain times and the inability of some women to aVord the cost of screening, only 30 of the 148 VDRL reactive serum samples were subjected to TPHA, with three being positive. Thus, 10% of the VDRL reactive sera were also TPHA reactive. This TPHA/VDRL ratio is...

A simple, improved, indirect hemagglutination test is described for the recognition of Type A strains of Pasteurella multocida. It involves the treatment of mucoid cultures with testicular hyaluronidase. Hydrolysis of the capsular hyaluronic acid presumably releases the specific antigen for adsorption to erythrocytes.