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Keywords: Transfusion medicine; Blood banks; Virus diseases; Epidemics; Infectious diseases; Virology; Poxviridae infections EN Transfusion medicine Blood banks Virus diseases Epidemics Infectious diseases Virology Poxviridae infections 206 208 3 03/21/23 20230315 NES 230315 Ongoing surveillance for emerging and re-emerging infectious diseases is essential to assess their impact on blood and breastmilk safety Before 2022, human mpox (formerly monkeypox) was rarely reported outside Africa,[1] but in May 2022, an outbreak of human mpox was reported in historically non-endemic countries. Since the 2022 outbreak, the Australian Red Cross Lifeblood (www.lifeblood.com.au) has put in place specific MPXV deferrals whereby donors with diagnosed MPXV infection are deferred for four weeks from the date of recovery, and donors who are close contacts are deferred for four weeks from the date of last contact with the infectious person. Transfusion medicine, Blood banks, Virus diseases, Epidemics, Infectious diseases, Poxviridae infections, Virology In addition, for donations used to manufacture plasma-derived products, the virus inactivation and removal steps would likely inactivate infectious MPXV if present.[19] Despite MPXV being theoretically transfusion-transmissible, no cases have been reported. [Extracted from the article]

Background and objectives: Based on the Council of Europe directive which dictates regulatory requirements in Australia, blood donors are currently deferred from donating for 4 months after an endoscopic procedure if either polyps were removed or a biopsy sample was taken. We aimed to assess the incidence of blood‐borne viruses (BBVs) (HIV, hepatitis B and C) in blood donors who donated after an endoscopic procedure and evaluate the risk to blood safety through risk modelling. Materials and methods: Donors from 1/1/2013 to 31/12/2017 with an endoscopy deferral on their blood donor file with pre‐ and post‐BBV testing were analysed to determine an incidence of BBVs using standard methods. The standard blood donor cohort was used as a comparator group. Using the incidence of endoscopies and BBV risk, the total residual risk estimate of allowing donors to return postendoscopy without restriction was calculated. Results: The incidence of a BBV postendoscopy in this large cohort of 16,283 where testing has been confirmed postendoscopy was zero (95% CI 0–0·000105). The upper confidence interval of the zero events is 10·5 per 100 000 donations. Total positive donations from 2017 repeat donors were 1·87 per 100 000 (95% CI 0·0000117–0·0000277). Sensitivity analysis demonstrated that the residual risk remained negligible under realistic worst‐case scenarios. Conclusion: A BBV endoscopy deferral is not required for blood safety in Australia. The presented data has enabled us to submit a request for an exemption to our regulator, which has been approved and the policy change subsequently implemented by Lifeblood on 4/4/2020. [ABSTRACT FROM AUTHOR]

Background: Occult hepatitis C infection (OCI) is a type of hepatitis C virus (HCV) infection, defined as the presence of HCV RNA in hepatocytes or peripheral blood mononuclear cells (PBMCs) and the absence of HCV RNA in serum.Study Design and Methods: A literature review was conducted to identify articles that characterized OCI as a disease, including its epidemiology, mode of transmission, pattern of infection, progression, and treatment.Results: OCI patients experience a milder degree of inflammatory and cirrhotic changes than patients with chronic hepatitis C. OCI is transmissible parenterally both in vivo and in vitro, however the duration and outcome of OCI remains unclear. OCI is most consistently found in patients with previous hepatitis C disease and hemodialysis patients. Beyond the at-risk populations, OCI has also been demonstrated among healthy individuals and blood donors.Conclusions: This review summarises our current understanding of OCI and suggests areas for further research to improve our understanding of this phenomenon, including a better understanding of its epidemiology and full clinical course. The current understanding of OCI and its clinical implications remain limited. Further standardized detection methods, ongoing surveillance, and investigation of its potential transmissions are required. [ABSTRACT FROM AUTHOR]

False positive (FP) viral marker results in blood donors continue to pose many challenges. Informing donors of FP results and subsequent deferral can result in stress and anxiety for donors and additional complexity and workload for blood services. Donor management strategies need to balance the requirement to minimise donor anxiety and inconvenience while maintaining sufficiency of supply. Decisions about how and when to inform donors of FP results and determine deferral periods can be difficult as FP results, while often transitory, can take up to several years to resolve. Additional complexities include the interpretation of indeterminate serological confirmatory testing without detectable viral RNA or non‐discriminated NAT results with concomitant anti‐HBc reactivity ‐ both may be due to FP results, but the former may also represent past infection and the later may represent occult hepatitis B infection. In this review we discuss strategies to minimise indeterminate serological confirmatory results, possible donor deferral policies and the impact on donors when notified of FP results. We also provide some new data from Australia that address the challenge of interpreting non‐discriminated NAT results with concomitant anti‐HBc reactivity. Ultimately, the challenge is for each blood service to develop appropriate strategies for donor management, taking into account local information and requirements. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses various reports within the issue on topics including identification of hepatitis C virus (HCV), cost-effectiveness of HCV screening strategies for blood donors and risk estimation of transfusion transmission.

Background We present an analysis of the first 2 years of hepatitis B virus ( HBV) nucleic acid testing ( NAT) of the Australian donor population. Study Design and Methods Between July 5, 2010, and July 4, 2012, all blood donations were screened for HBV DNA and hepatitis B surface antigen ( HBsAg). Donors who tested HBsAg negative but HBV NAT positive were assessed as occult hepatitis B infections ( OBI) if reactive for antibodies to HBV core antigen (anti- HBc). Donors who were anti- HBc reactive but with nonrepeatable or nondiscriminated NAT results were assessed as HBV inconclusive pending follow-up testing. Results During the study period a total of 2,673,521 donations were screened for HBV. Forty-two chronic OBI infections (5.55/100,000 donors) were identified compared to eight acute serologic window period infections (1.06/100,000 donors). Of the 42 OBI cases, 23 (54.8%) were detected the first time they were screened for HBV DNA while 19 (45.2%) gave one or more HBV NAT-nonreactive results before detection. Of 68 donors initially assessed as HBV inconclusive and available for follow-up, 10 later confirmed as OBI cases while 51 were NAT nonreactive but remained anti- HBc reactive and OBI could not be excluded. Conclusion This study demonstrated a substantially higher prevalence of OBI compared to acute serologic window period HBV infections in Australian blood donors. Follow-up testing of OBI cases indicates that HBV DNA is often only intermittently detectable in OBI, highlighting the importance of including anti- HBc to optimize the HBV testing algorithm. [ABSTRACT FROM AUTHOR]

Male-to-male sex is the predominant route of human immunodeficiency virus (HIV) transmission in Australia and since the early 1980s blood services in Australia have deferred donors for this practice for at least 5 years. This retrospective analysis assesses the impact on HIV prevalence of implementing an abridged 12-month deferral for male-to-male sex. The prevalence of HIV among blood donors for 5-year periods before (Period 1) and after (Period 2) implementing the revised 12-month deferral was compared. Using deidentified data from postdonation interviews with HIV-positive donors the proportion disclosing male-to-male sex as a risk factor was compared for the two periods. Twenty-four HIV-positive donations were identified among 4,025,571 donations in Period 1 compared with 24 among 4,964,628 donations in Period 2 (p = 0.468). The proportion of HIV-positive donors with male-to-male sex as a risk factor in Period 1 was 2 in 15 (13.3%), which was not significantly different from the proportion in Period 2, 5 in 16 (31.25%; p = 0.22). All five men who have sex with men risk HIV infections during Period 2 were from donors whose risk was within the 12-month criterion for acceptability, who would have been deferred had they provided a complete history. We found no evidence that the implementation of the 12-month deferral for male-to-male sex resulted in an increased recipient risk for HIV in Australia. The risk of noncompliance to the revised deferral rather than its duration appears to be the most important modifier of overall risk. [ABSTRACT FROM AUTHOR]

BACKGROUND: High sample-to-cutoff (s/co) ratios on hepatitis C virus antibody (anti-HCV) screening immunoassays (IAs) are indicative of confirmed-positive results and, according to some reports, can be used to determine anti-HCV status without the need for confirmatory testing. The purpose of this study was to determine whether s/co ratios on hepatitis B surface antigen (HBsAg), antibody to human immunodeficiency virus Types 1 and 2 (anti-HIV-1/2), anti-HCV, and antibody to human T-lymphotropic virus Types I and II (anti-HTLV-I/II) chemiluminescent immunoassays (ChLIAs) can be used to discriminate between biologic false-reactive (BFR) and confirmed-positive results. STUDY DESIGN AND METHODS: In a blood donor population the s/co ratio distributions for BFR and confirmed-positive results were compared for the Abbott PRISM HBsAg, HIV O Plus, HCV, and HTLV-I/II ChLIAs to determine the extent of overlap between the two distributions for each assay. RESULTS: The s/co ratio distributions for BFR and confirmed results overlapped in the range of 10.00 to 60.00, 1.00 to 6.00, 3.00 to 15.00, and 1.00 to 100.00 for the PRISM HIV O Plus, HCV, HTLV-I/II, and HBsAg assays, respectively. CONCLUSION: Although high s/co ratios were predictive of confirmed-positive results in all four assays, a number of confirmed-positive samples gave low values while some biologic false-positive samples showed high values. As the s/co ratio distributions for BFR and confirmed-positive results overlapped for all four PRISM assays, this study highlights the importance of serologic confirmatory testing and the need for caution when using screening IA results to assign a final donor status. [ABSTRACT FROM AUTHOR]

BACKGROUND: This study reports the results of the long-term serologic follow-up of blood donors who gave an index biologic false-reactive (BFR) result on an anti-human T-lymphotropic virus Types I and II (HTLV-I and -II) chemiluminescent immunoassay (ChLIA). STUDY DESIGN AND METHODS: All allogeneic whole-blood and apheresis donors who gave an index BFR result on a HTLV-I and -II ChLIA between May 10, 1997, and December 31, 2004, were included in the study. Donors were followed up for an additional 2 years until December 31, 2006. RESULTS: A total of 332 donors gave an index BFR donation during the study period. Donors were divided into five groups based on results of donations subsequent to the index BFR donation: 89 (26.8%) donors gave only nonreactive donations subsequent to the index BFR result, 56 (16.9%) donors gave only BFR donations, 43 (13.0%) gave one or more subsequent BFR donations before giving only nonreactive donations, 59 (17.8%) donors gave intermittent BFR and nonreactive donations, and 85 (25.6%) donors gave no further donations during the study period. The estimated mean duration of biologic false reactivity from the time of the index BFR donation in donors who gave only a single BFR result was 7.0 (1.4-42.75) months and 23.3 (4.1-92.25) months in those donors who gave several BFR results before giving nonreactive donations. Modeling of the data indicated that notification and deferral of donors after two consecutive BFR donations would result in the deferral of 143 of 332 (43.1%) of donors with an index BFR result while allowing donors to give three BFR results would reduce the number of deferred donors to 74 of 332 (22.3%). CONCLUSION: The results of this study indicate that although biologic false reactivity is usually transient, the time for resolution is variable. Allowing donors to give two or three BFR results before notification and deferral is one strategy that would substantially reduce the number of donors requiring deferral. [ABSTRACT FROM AUTHOR]

One of the problems associated with the use of anti-HCV immunoblot assays is the inter-pretation of indeterminate results without detectable HCV RNA. The purpose of this study was to examine the significance of third-generation RIBA (RIBA-3)-indeterminate, RNA-negative results in voluntary blood donors. Since June 2000 all Australian Red Cross Blood Service testing sites have used an anti-HCV sequential immunoassay testing strategy whereby donors who are reactive on the primary screening immunoassay are tested on a secondary immunoassay and if reactive on both assays, further tested by immunoblot. From the four testing sites that use RIBA-3, the result profiles of donors who were RIBA-3-indeterminate, HCV RNA-negative were analyzed. From 2,661,786 donations screened for anti-HCV during the study period, 102 RIBA-3-indeterminate, RNA-negative donors were identified, most of whom were reactive to either c33p (69.6%) or c22p (27.5%). The RIBA-3-indeterminate, RNA-negative donors showed a significantly higher screening immunoassay signal strength to assay cutoff (S/CO) distribution than those with biologic false-reactive (BFR) results (1.853 vs. 1.524, p < 0.05) but a significantly lower distribution than RIBA-3-positive, RNA-negative (1.853 vs. 4.546, p < 0.05) or RNA-positive (1.853 vs. 6.467, p < 0.05) donors. The RIBA-3-indeterminate, RNA-negative donors showed a similar distribution of c33c and c22p band intensities compared with RIBA-3-positive, RNA-negative donors but significantly lower distribution of band strengths compared to the RIBA-3-positive, RNA-positive group. Compared to the indeterminate donors with previous anti-HCV-negative or BFR results, the indeterminate donors not previously screened for anti-HCV showed higher immunoassay S/CO ratio distributions, a higher proportion with c22p reactivity (16.2% vs. 36.7%), and higher frequency of risk factors (46.4% vs. 75.0%). Our analysis suggests that a combination of indicators can be used to help clarify RIBA-3-indeterminate, RNA-negative results. Specifically, donors with high S/CO ratios on a screening immunoassay, RIBA-3 reactivity to c22p or c33c with band intensity of 2+ or greater, without a previous history of negative or BFR donations and with an identifiable risk factor, have a high probability of representing true anti-HCV rather than nonspecific reactivity. [ABSTRACT FROM AUTHOR]

BACKGROUND : Biologic false-reactive (BFR) results in blood donors are problematic due to both component loss and donor-management issues. This report analyzes the results of a longitudinal study of BFR donors and the implications for donor management. STUDY DESIGN AND METHODS : Donors who gave BFR results on HBsAg, HIV-1/HIV-2, HCV, or HTLV-I/HTLV/II chemiluminescent immunoassays (ChLIAs) (PRISM, Abbott) between May 1997 to March 1999 were analyzed. Donors were followed up for up to three donations after an index BFR episode. In addition, results of any negative donations before the index BFR result but within the study period were included in the analysis. RESULTS : For donors who gave an index BFR result on the HBsAg ChLIA, 14.3 percent remained BFR at subsequent donations, whereas for the anti-HIV-1/HIV-2, anti-HCV, and anti-HTLV-I/HTLV-II ChLIAs, the figures were 66.0, 77.4, and 71.6 percent, respectively. For donors who gave a second BFR result, the percentage who remained BFR at subsequent donations was 75.0, 80.6, 84.6, and 74.5 percent for the four assays, respectively. The rate at which negative repeat donors became BFR during the study period was 0.02, 0.07, 0.12, and 0.02 percent for the HBsAg, anti-HIV-1/HIV-2, anti-HCV, and anti-HTLV-I/HTLV-II assays, respectively. CONCLUSIONS : Our results indicate that donors who give an index BFR result on the ChLIAs (PRISM, Abbott) should be allowed to continue donating because most donors with a HBsAg BFR result were negative at subsequent donations, and between 22.6 and 34.0 percent of those with BFR results on the HIV-1/HIV-2, HCV, or HTLV-I/HTLV-II assays gave subsequent negative donations. However, donors who give a second BFR result should be counseled and deferred because they were very unlikely to give subsequent negative results. [ABSTRACT FROM AUTHOR]

Provides an assessment of the accuracy of the viral risk models in predicting the outcome of implementing HIV and HCV NAT donor screening in Australia. Rate of transmission in blood recipients; Application of mathematical risk modeling to derive risk estimates; Implementation of the screening method.

Compares two anti-hepatitis C virus (HCV) immunoblot assays for its sensitivity to HCV among voluntary blood donor population. Anti-HCV testing algorithms; Genotyping and serotyping results; Reason for the difference in sensitivity of the two immunoblots.