Estimation of incidence of respiratory syncytial virus infection in schoolchildren using salivary antibodies

Abstract

An assay for respiratory syncytial virus (RSV)-specific IgG in saliva is described. The assay was used to examine the incidence of RSV infection in schoolchildren 7-10 years old during one RSV season. One hundred and twenty-one volunteer children provided saliva samples in October 1997 and March 1998; 18% of the children showed a fourfold or greater rise in anti-RSV IgG in the second sample. This prevalence of antibody increase is similar to that described in previous studies that measured CFT levels in serum samples. Overall, the children who showed rises in antibody levels, indicating that they had experienced an RSV infection, had lower levels of RSV-specific antibody in their preseason samples than those who showed no increase (P = 0.0018). These results show that saliva is an adequate substitute for serum in some antibody tests and may be useful for community studies. Such studies may provide surrogate markers for susceptibility to infection, which should benefit the planning of vaccination strategies.

Symptomatic Respiratory Syncytial Virus Infection in Previously Healthy Young Adults Living in a Crowded Military Environment

“…Serum titers of IgG antibodies against RSV were measured with an ELISA modified from standard methods [23]. Positive antigens (pooled, high-titered lysates of multiply-passaged RSV A2 and B-infected cells) and negative antigens (mock-infected control cell lysate) were prepared in 0.5% Nonidet P40 (vol/vol).…”

Genetic Variability and Molecular Evolution of the Human Respiratory Syncytial Virus Subgroup B Attachment G Protein

“…HRSV infections occur continually throughout life, which is indicative for partial cross-immunity against different strains (18,23,69). Children initially infected with an HRSV-A strain appear more likely to experience reinfection with an HRSV-B strain (37,65).…”

Identifying Infections with Respiratory Syncytial Virus by Using Specific Immunoglobulin G (IgG) and IgA Enzyme-Linked Immunosorbent Assays with Oral-Fluid Samples

“…Oral fluid was collected using a well-evaluated (10, 19) sponge device (Oracol; Malvern Medical Development, Worcester, United Kingdom) that was rubbed firmly along the gums for 1 min. Extraction and storage methods are detailed elsewhere (11,21). Ethical approval for this study was provided by the Kenya National Ethical Review Committee and the Coventry Research Ethics Committee, Coventry, United Kingdom.…”

“…Serum samples and controls were similarly diluted but at a 1/100 dilution. The remainder of the specific-antibody assay was carried out as previously described (21). Samples were tested for both IgG and IgA antibodies using horseradish peroxidase-conjugated rabbit anti-human IgG and horseradish peroxidase-conjugated rabbit anti-human IgA (Dako) (1/1,000), respectively.…”

“…Oral fluid has also been used successfully to determine current human immunodeficiency virus infection status (18). In the case of RSV, one study utilized repeated oral-fluid samples for the detection of specific IgG boosting in order to estimate incidence among schoolchildren in the United Kingdom (21). However, the assay was not evaluated against paired serum specimens, and there was no confirmation of infection by a virus detection test.…”