Self-reported symptoms associated with West Nile virus infection in RNA-positive blood donors.

BACKGROUND: In 2003, West Nile virus (WNV) nucleic acid amplification testing (NAT) was implemented to detect potentially infected donors. Of more than 5.3 million donations screened prospectively by the American Red Cross during the epidemic periods of 2003 and 2004, 974 were NAT-reactive and 519 confirmed-positive. A subset of both the confirmed-positive and the false-positive groups was assessed for demographic characteristics, symptoms, and symptom reporting relative to date of donation. STUDY DESIGN AND METHODS: All donors with initial WNV NAT-reactive results were invited to participate in a study that included a demographic, symptom, and date-of-symptom questionnaire. WNV confirmed-positive cases were compared to false-positive controls for comparison of frequency of symptom reporting before, on the day of, and after donation. RESULTS: Enrolled cases and controls were similar in all characteristics except cases were more likely to live in rural areas. Symptoms were reported by 61 percent of cases versus 20 percent of controls, with 74 percent of symptoms reported by cases within the 14 days after donation. The frequency of headache and fever reported together in the 7 days before donation was not significantly different between cases and controls; only the individual frequencies of headache, eye pain, and new rash during this time were significantly different. The most commonly reported symptoms, after adjustment for symptom reporting by controls, were headache, new rash, and generalized weakness; these symptoms were reported by 25 percent of cases. CONCLUSIONS: The demographic characteristics of infected donors reflected the rural nature of the 2003 to 2004 WNV epidemics. This study suggests that asking donors about predonation headache and fever had no detectable contribution to blood safety.

Risk factors for HCV infection among blood donors confirmed to be positive for the presence of HCV RNA and not reactive for the presence of anti-HCV.

BACKGROUND: In 1999, NAT of blood donations was implemented to detect "window-period" infections. Blood donors who have confirmed NAT results positive for the presence of HCV in the absence of anti-HCV are likely to have been recently infected. Of over 26.8 million donations tested between March 3, 1999, and March 31, 2003, 810 were HCV-reactive by NAT. A subset of these donors was assessed for recent exposure risk. STUDY DESIGN AND METHODS: All anti-HCV- blood donors with reactive, unconfirmed HCV NAT results were invited to participate in a study that included an extensive demographic and risk questionnaire. Confirmed HCV+ cases were compared to HCV- (falsely positive) controls for histories of potential risk factors during the 6 months before donation. RESULTS: Recent injection drug use (IDU) was independently associated with HCV infection (29.2% vs. 0% of cases vs. controls, p < 0.001). In addition, likely sources were identified for three other cases (4.6%), including occupational exposure, sexual contact with an HCV-infected partner (who was an IDU), and perinatal exposure, none of which was known to the donors at the time of donation. Incarceration was independently associated with HCV infection among the group not reporting IDU and after removal of the three donors with likely sources of risk (14.6% vs. 1.3% of cases vs. controls, p < 0.001). CONCLUSIONS: A likely risk, primarily IDU, was found for 43 percent of HCV+ donors whose infections were identified solely by NAT. Because the maximum efficiency of the donor history questions may have been reached, NAT will continue to be an important measure to interdict recently infected blood donors.

Simian foamy virus infection in a blood donor.

BACKGROUND: Infections with simian foamy virus (SFV) are widely prevalent in nonhuman primates. SFV infection was confirmed in a worker, occupationally exposed to nonhuman primates, who donated blood after the retrospectively documented date of infection. Human-to-human transmission of SFV through transfusion and its pathogenicity have not been studied. STUDY DESIGN AND METHODS: Recipients of blood from this donor were identified and blood samples from such recipients were tested for SFV infection by Western blot and PCR assay. RESULTS: One recipient of RBCs and another recipient of FFP had died; retroviral infections were not implicated. One platelet recipient could not be tested. Recipients of RBCs (two), a WBC-reduced RBC unit (one), and a platelet unit (one) tested SFV-negative 19 months to 7 years after transfusion. Tested recipients had transfusions 3 to 35 days after blood donation. Samples of one lot of albumin and three lots of plasma protein fraction (manufactured from recovered plasma from two donations) tested negative both for antibodies and for viral RNA. CONCLUSION: SFV transmission through transfusion was not identified among four recipients of cellular blood components from one SFV-infected donor. Derivatives containing plasma from that donor tested negative for SFV.

Absence of risk factors for false-positive test results in blood donors with a reactive test result in an automated treponemal test (PK-TP) for syphilis.

BACKGROUND: Screening and confirmatory serologic tests for syphilis are known to generate false-positive results in low-risk populations, which include blood donors. This study assessed whether conditions previously reported to cause biological false-positive (BFP) test results for syphilis are relevant to contemporary syphilis testing of blood donors and the extent to which seropositive donors report a history of syphilis. STUDY DESIGN AND METHODS: A history of conditions reported to be associated with BFP syphilis tests or a history of syphilis infection was assessed by a case-control study of donors with reactive and nonreactive automated treponemal test results, using an anonymous mail survey. Analysis of cases was stratified by fluorescent treponemal antibody absorption (FTA-ABS) result. RESULTS: Adjusted ORs (95% CIs) for reported BFP-associated conditions were 1.3 (0.8-2.1) for FTA-ABS-positive cases and 0.8 (0.3-1.9) for FTA-ABS-negative cases. Among responding blood donors, syphilis history was reported in 78 (51%) of 153 FTA-ABS-positive cases, 0 of 142 FTA-ABS-negative cases, and 3 (0.4%) of 716 automated treponemal test (PK-TP)-negative controls. CONCLUSION: Approximately half of donors with FTA-ABS-positive test results reported a syphilis history. There was no difference between reported BFP conditions for FTA-ABS-positive or FTA-ABS-negative cases and controls. This information may be useful when providing donors with better predonation or post-test counseling information about syphilis testing.

Seroprevalence of known and putative hepatitis markers in United States blood donors with ALT levels at least 120 IU per L.

BACKGROUND: ALT testing of blood donors was initiated as a surrogate marker for non-A, non-B hepatitis. Increased sensitivity of subsequent HBV and HCV tests used for standard donor screening make any residual value of ALT testing questionable. STUDY DESIGN AND METHODS: A prospective study was conducted in 166 of 645 eligible blood donors from three American Red Cross regions whose ALT was > or =120 IU per L and whose standard donor screening tests were negative. Of these enrolled donors, 124 (75%) completed follow-up. Samples obtained from the index donation, at enrollment (1 month), and at follow-up (6 months) underwent the standard donor screening tests, as well as those for HCV RNA and HGV RNA (RT-PCR), antibodies to the virus envelope E2 protein of GB virus type C (GBV-C E2 antibody), and IgM antibody for CMV, parvovirus B19, EBV VCA, and HAV. Participants completed a brief demographic and exposure history questionnaire at follow-up. RESULTS: All study samples were negative in standard donor-screening tests. ALT levels were variable at return visits, with 80 to 86 percent <120 IU per L. No participants were positive for HCV RNA; 4 percent were positive for HGV RNA, and 10 percent were positive for GBV-C E2 antibody. Results of CMV, parvovirus B19, EBV VCA, and HAV testing were similar to published background rates. No demographic or exposure history variables had significant correlation with ALT or other testing results. CONCLUSION: These data suggest that an ALT > or =120 IU per L in blood donors with negative standard screening tests has questionable value as a surrogate marker for seronegative HBV or HCV infection. Continued ALT testing may contribute little, if anything, to the safety of blood components or plasma for further manufacture.

Validation of selected donor-screening questions: structure, content, and comprehension.

BACKGROUND: Donor questioning is an integral component of blood safety, designed to identify and interdict donors considered to be at elevated risk of transfusion-transmissible infection. Questions are frequently added to this screening procedure, but they are rarely evaluated for comprehension. STUDY DESIGN AND METHODS: Seven American Red Cross blood donor history questions were selected for evaluation. Focus groups were conducted using individuals from high school/college, church, business, and other sources, who had never donated blood. Both sexes and various age and racial groups were represented. The donation process and regulatory requirements or guidelines were explained. Participants were asked to consider 1) content, 2) clarity 3) likelihood of asking for more information, 4) suggestions for improvement, and 5) how a need for clarifying information would best be met. RESULTS: Constructive, helpful, and consistent comments obtained might be utilized in revising questions. CONCLUSION: Focus group discussions can be useful in providing guidance for developing screening questions that can be easily understood.

Effect of urokinase on the extracellular virulence properties of Pseudomonas aeruginosa and Burkholderia cepacia.

The influence of urokinase and oxygen availability on growth, siderophore, protease and lipase production in Burkholderia cepacia and non-mucoid (PA01) and mucoid (PaWH) strains of Pseudomonas aeruginosa was assessed for cells grown in batch culture under iron-restriction. Siderophore production decreased with increasing concentration of urokinase in B. cepacia independent of oxygen availability but decreased in both strains of P. aeruginosa only under oxygen-depleted conditions. Protease activity was enhanced for all three strains irrespective of oxygen content whereas lipase production increased in B. cepacia and decreased in PA01 under both sets of growth conditions and varied with oxygen availability in PaWH. The evidence presented suggests that urokinase could contribute to the pathophysiology of pulmonary infections.

Predictive value of past and current screening tests for syphilis in blood donors: changing from a rapid plasma reagin test to an automated specific treponemal test for screening.

BACKGROUND: This study evaluated the change from a rapid plasma reagin (RPR) test to an automated specific treponemal test (PK-TP) in screening for syphilis in blood donors. STUDY DESIGN AND METHODS: A cross-sectional seroprevalence analysis was performed on 4,878,215 allogeneic blood donations from 19 American Red Cross Blood Services regions from May 1993 through September 1995. Positive predictive values relative to the confirmatory fluorescent treponemal antibody absorption test (FTA-ABS) were calculated. Differences in seroprevalence were compared in RPR and PK-TP tests for 1) unconfirmed and confirmed tests, 2) first-time and repeat donors, and 3) "recent" versus "past" infections. Donation data from three additional Red Cross regions were evaluated for repeat donation patterns of blood donors who had a donation that was positive in a serologic screening test for syphilis. The value of RPR and PK-TP tests as surrogate markers for HIV infection was compared. RESULTS: Reactive rates were lower but the positive predictive values was higher for the PK-TP test than for the RPR test. Initially, donors screened by PK-TP were more likely to be confirmed as positive than were donors screened by RPR, but these rates became comparable. It is estimated that a single HIV window-period donation was removed by serologic testing for syphilis each year of this study period. CONCLUSIONS: The change to the PK-TP test resulted in a lower repeatedly reactive rate, better prediction that a confirmed-positive test for syphilis would occur in testing in the FTA-ABS, fewer donations lost, and comparable deferral rates. Because of the high rate of reactivity to serologic testing for syphilis among donors previously confirmed positive for syphilis, indefinite deferral after a confirmed-positive index donation may be warranted. Serologic testing for syphilis is ineffective as a marker of HIV-infectious window-period donations.