Effect of specimen storage, antibiotics, and feminine hygiene products on the detection of group B Streptococcus by culture and the STREP B OIA test.

Agar culture from vaginal swabs is the routine method for diagnosis of maternal Group B Streptococcus (GBS) colonization. Swab specimens are often transported to a clinical laboratory for processing. In these studies, specimen transport was simulated by inoculating swabs with GBS and storing them at selected temperatures and with or without transport medium. The recovery of viable GBS was assessed by agar culture. GBS antigen was detected immunologically with an Optical ImmunoAssay (OIA) method. Swabs that were stored with transport medium harbored viable but rapidly declining numbers of GBS. In contrast, a strong OIA signal was maintained. Recovery of viable GBS organisms declined more quickly when swabs were stored in the absence of transport medium, whereas detection of GBS antigen remained consistent. Both methods were tested for interference from either antibiotics or feminine hygiene products. These compounds inhibited the detection of GBS by culture but had no detrimental effect on the OIA result.

The prevalence of antibody to HTLV-I/II in United States plasma donors and in United States and French hemophiliacs.

Antibody to HTLV-I/II was detected in 19 (0.3%) of 6286 plasma donors from five regions of the United States (US). This seroprevalence rate is approximately 10 times that in whole blood donors. The regional distribution of infection was as follows: Southwest, 0.68 percent; Southeast, 0.45 percent; Midwest, 0.28 percent; Northwest, 0.1 percent; and Northeast, 0.0 percent. Rates of HTLV-I/II infection in blacks (0.74%) and Hispanics (0.66%) were higher (both, p less than 0.001) than those in whites (0.08%). All 19 infected units were donated by subjects aged 30 or older, even though 52.9 percent of the donations came from persons less than 30 years old. Equal rates of HTLV-I/II infection were found in men (0.31%) and women (0.29%). No HTLV-I/II antibody was detected in 154 French and 25 US hemophiliacs who were transfused regularly with noninactivated plasma or its derivatives. This suggests that the transfusion of HTLV-I/II-seropositive plasma products does not transmit the viral infection.

Human T-cell lymphotropic virus in volunteer blood donors.

Serum samples collected in 1985 and 1986 from 18,257 donors to the Greater New York Blood Program were screened by enzyme-linked immunoassay for antibody to human T-cell lymphotropic virus (anti-HTLV). Fifteen samples (0.08%) were confirmed positive: 7 by radioimmunoprecipitation assay (RIPA) alone, 6 by Western blot alone, and 2 by combined results from both tests. One donor, whose original test result was uninterpretable because multiple nonspecific bands were present on RIPA, clearly tested positive on subsequent specimens. Follow-up testing of individuals with this type of result may be needed to resolve their HTLV status. Anti-HTLV prevalence increased with age and was significantly more common in black or Hispanic donors and in those born in the Caribbean than in other donors. All anti-HTLV-positive donors were negative for antibody to HIV-1, and only one donor (7% of those positive) would have been excluded by any of the routine donor screening tests used at that time.