Detection of measles, mumps, and rubella antibodies in saliva using antibody capture radioimmunoassay

SUMMARYA method for the analysis of age-stratified antibody prevalence surveys is applied to a previously reported survey of antibody to rubella virus using oral fluid samples in which the sensitivity of the assay used was shown to be compromised. The age-specific distribution of the quantitative results of antibody tests using oral fluids is modelled as a mixture of strong positive, weak positive and negative components. This yields maximum likelihood estimates of the prevalence at each age and demonstrates that, when used in conjunction with mixture modelling techniques, the results of antibody prevalence studies using oral fluids accurately reflect those obtained using sera.

Section: Discussionmentioning

confidence: 99%

Improving sensitivity of oral fluid testing in IgG prevalence studies: application of mixture models to a rubella antibody survey

Vyse¹,

Enquselassie

Nigatu

et al. 2003

“…Saliva samples were tested for measles-specific IgG using a G-antibody capture radioimmunoassay (GACRIA) [11]. Saliva samples were considered positive if they gave a test/negative control ratio of > 2 1 [11].…”

Section: Analysis Of Samplesmentioning

confidence: 99%

“…Saliva samples were considered positive if they gave a test/negative control ratio of > 2 1 [11]. Serum and saliva samples were tested for measles-specific IgM by M-antibody capture radioimmunoassay (MACRIA) as previously described [11] and for measles-specific IgG by plaque reduction neutralization (PRN). The PRN method was similar to previously described methods [12] with two minor modifications.…”

Section: Analysis Of Samplesmentioning

confidence: 99%

Measles immunity and response to revaccination among secondary school children in Cumbria

Calvert¹,

Cutts

Irving³

et al. 1996

SUMMARYThe prevalence of antibody to measles virus in 759 children aged 11-18 years attending a secondary school in Cumbria was measured using a salivary IgG antibody capture assay. Serum IgG antibody levels were measured using a plaque reduction neutralization assay in subjects whose saliva was antibody negative. Vaccination histories were obtained from the child health computer and general practice records. A total of 662 pupils (87 % of those tested) had detectable measles-specific IgG in saliva. Of the remaining 97, 82 provided blood samples and 29 had serum neutralizing antibody levels above 200 mIU/ml. After adjusting for non-participation rates, the proportion considered non-immune (no IgG in saliva and < 200 mIU/ml in serum) was 9 % overall, ranging from 6% in vaccinated children to 20% in unvaccinated children. Measles-mumps-rubella vaccine was given to 50 children of whom 38 provided post-vaccination serum and 32 saliva samples. Thirty (79 %) had a fourfold or greater rise in serum neutralizing antibody and 28 (88 %) developed IgG antibody in saliva. Half of the children considered non-immune by antibody testing would have been overlooked in a selective vaccination programme targeted at those without a history of prior vaccination. A programme targeted at all school children should substantially reduce the proportion nonimmune since a primary or booster response was achieved in three quarters of previously vaccinated children with low antibody levels and in all unvaccinated children. While it is feasible to screen a school-sized population for immunity to measles relatively quickly using a salivary IgG assay, a simple inexpensive field assay would need to be developed before salivary screening and selective vaccination could substitute for universal vaccination of populations at risk of measles outbreaks. The salivary IgG assay provided a sensitive measure of a booster response to vaccination.

“…Blood samples were taken from 19 notified and 11 non-notified cases of measles and sent to the PHLS Virus Reference Laboratory at Colindale for examination for measles specific IgM [11].…”

Section: Laboratory Testsmentioning

confidence: 99%

Successful control of a school based measles outbreak by immunization

Lyons¹,

Jones

Salmon³

1994

SUMMARYIn an outbreak of measles in North Wales centred on a secondary school in 1991, 74 cases occurred over a period of 51 days. Before the outbreak started, 27 % pupils did not have a history of measles or immunization and were considered susceptible. Active case finding and identification and vaccination of susceptible contacts commenced after the fourth generation of cases and further reduced the pool of susceptible schoolchildren from 17 %, at the onset of the vaccination campaign, to 8 %. A fifth generation of cases did not occur. Delays in diagnosis (mean 2-8 days) and notification (mean 6-1 days) hampered control. There was no evidence of primary vaccine failure (observed vaccine efficacy 97 %). Sixty-nine (93 %) cases were considered preventable. Reasons for the apparent success of the intervention are discussed.