The objective of the TTID WP is to evaluate and advance the safety of blood transfusion by analysing infectious diseases, interventions to prevent transfusion-transmission, coordinating international studies, and publishing scientific reports.
Chairperson and committee
Chairperson: Brian Custer (USA)
Vice Chair: Sheila O’Brien (Canada)
Secretary: Michel García-Otálora (Colombia)
Corporate Member Representative: Marcia Cardoso (Terumo BCT)
Individual Member Representatives:
- Thijs van de Laar (the Netherlands) and Karin van den Berg (South Africa)
Subgroup coordinators:
Bacteria: Sandra Ramirez-Arcos (Canada), Carl McDonald (UK)
Parasites: Evan Bloch (USA), Steven Drews (Canada), Silvano Wendel (Brazil)
SRAP: Sheila O’Brien (Canada), Katy Davison (UK)
Virology: Helen Faddy (Australia), Daniel Candotti (France)
Membership
The TTID WP has 196 members from 42 countries.
The number of TTID members is 196 from 42 countries. While participation in the activities of each subgroup is open to all TTID members, each member is asked to identify a primary subgroup. Not all members have identified a primary subgroup. The current subgroup member distribution is Bacteria (37), EPP (15), SRAP (30), and Virology (59). Membership is also classified according to professional role or institution with 158 individual members with expertise in TTID, 20 corporate partner members, 6 institutional members, and 12 observer members. The observer member category is a temporary category, and individuals may become individual members.
Meetings
Administrative management of TTID is conducted by the Organising Committee. The committee primarily conducts its work by email and meets as needed to discuss business matters. The TTID annual business meeting is held at as part of one of the ISBT annual congresses (European or Global depending on the year). The meeting is a hybrid format so that both in-person congress attendees and those who cannot attend in person can participate. Our 2025 annual business meeting was held on May 31, 2025, in Milan, Italy. The agendas for our annual business meeting are posted on the ISBT website along with most of the presentations from each annual meeting. In the period covering this annual report the Organising Committee identified the need to make significant updates to our sections of the ISBT website focused on the work we do and the public health toolkit. This work is ongoing and is intended to make the content shared on ISBT website about TTID more topical, current, and easier to navigate.
The scientific insights developed by TTID are primarily accomplished through the work of the four subgroups. Each subgroup meets virtually in each quarter of the year to discuss specific topics relevant to the charge of the subgroup and to specifically advance topics of interest, totalling 12 online TTID meetings per year. Additional topic specific meetings are scheduled as needed. Each subgroup meets in a hybrid format as part of annual meetings of TTID at congresses to specifically discuss the work of the subgroup and to plan directions for the next year.
Activities during the period
The TTID subgroups have been successful in seeking small grants from ISBT to conduct specific projects as part of TTID. Each year, approximately two funding request proposals are approved by the ISBT Board for TTID related studies. In the 2024-2025 reporting year, two projects were funded and the work of those projects has continued into this reporting year. These two studies are Virology subgroup projects. One study is titled, “S mutations leading to hepatitis B surface antigen intracellular retention in HBsAg-negative blood donors and pathophysiological risks.” The project focuses on mutations related to occult HBV infection and further defining the relevant mutations through international sample acquisition and testing. The laboratory work for this study is completed, and manuscripts reporting findings are in preparation. The second study is titled, “Obtaining evidence for a submission to WHO, ISBT, AABB, FDA, PEI to stop anti-HCV screening of blood donations in countries that perform ID-NAT.” Sample testing for this study has been mostly completed and results will be presented at congresses in 2026. Manuscripts of findings are in development.
In the 2025-2026 reporting year, two new projects received funding. First, a project titled, “Growth promotion of Staphylococcus aureus”. The rationale for this study is that because of the increasing number of cases of platelet concentrates (PC) contaminated with S. aureus, it is necessary to ensure that growth culture media used for PC screening supports growth of S. aureus to minimize false-negative PC screening that could result in transfusion of contaminated units posing a significant safety risk to PC recipients. Second, a project titled, “Prevalence of Occult Hepatitis B Among Blood Donors at Cape Coast Teaching Hospital, a Pilot Study”. By investigating the prevalence of occult hepatitis B among blood donors at Cape Coast Teaching Hospital in Ghana, the study will provide site-specific data on residual transfusion risk in West Africa and support evidence-based improvement of local blood safety practices in countries in Africa. Both projects are currently in the final design and implementation phase.
Subgroup Activity Updates
Bacteria
- Completed projects:
- Bacterial growth in delayed cold-stored platelet components. Seven participant laboratories worldwide. Abstract accepted for an oral presentation at the ISBT 2026 Congress. Manuscript in preparation and planned to be submitted for peer-reviewed publication by December 2026.
- Endotoxin detection in platelet concentrates in collaboration with the Paul-Erlich-Institut. Six participant laboratories worldwide. Study partially funded by ISBT. Manuscript in preparation and planned to be submitted for peer-reviewed publication by June 2026.
- International survey on donor/donation screening for syphilis.
- New study:
- Growth promotion of Staphylococcus aureus in culture bottles. Eight potential participant laboratories worldwide. Proposal to obtain partial funding have been submitted to ISBT and bioMérieux. Study to be executed in fiscal year 2026-2027.
Emerging Pathogens and Parasitology (EPP)
- In a July 2025 EPP meeting, the horizon scanning approach was reviewed with the group; team members were asked to identify variables for prospective information searches. Contributing team members were enlisted as authors for a manuscript to define the objectives of the newly established EPP group.
- In November 2025, a Fall quarterly meeting was convened and team members were asked about knowledge translation products for prioritization. These were included in the manuscript defining the objectives of the EPP group.
- In the Winter of 2025, three surveys were distributed to EPP members to elicit information as to who members are currently conducting searches for information pertaining to emerging and re-emerging pathogens. The findings were discussed at an EPP quarterly meeting in March 2026.
- After the March meeting it was decided that an artificial intelligence (AI)-assisted approach will be presented at the meeting in Kuala Lumpur.
Surveillance, Risk Assessment and Policy (SRAP)
- International surveys. The PrEP/PEP Survey reviewed deferral policies related to PrEP/PEP use, mapping global policy, donor screening and testing practices, and identifying barriers and best practices to support harmonisation. Twenty‑seven services responded, and findings will be presented at ISBT Kuala Lumpur 2026. The Optimising Inclusion Post‑IDRA Survey assessed the impact of policy changes on transgender and non‑binary donors. Thirteen services responded. Most countries still operate within binary systems, though some have implemented workarounds. Questionnaires were finalised for the Blood Bank Deferral Due to Antigen Risk survey, which will evaluate current practices and explore potential improvements. Initial discussions have also begun on a further lookback survey.
- Public Health Toolkit. Originally developed to support collaboration between public‑health agencies and blood services after the pandemic, particularly around seroprevalence studies. A review is now underway to reassess its purpose and ensure it meets current needs. A user survey has been designed to gather feedback, and an article for Transfusion Today is in preparation.
- ISBT Workshop A proposal was accepted for the ISBT 2026 main programme in Kuala Lumpur: Outbreak Preparedness and Blood Safety in Resource‑Limited Settings: Practical Lessons from the Field.
- New projects. Scoping has begun on developing standardised terminology to support TTID WP members and wider ISBT networks. Also, discussions are underway on a survey to assess reintegration pathways for donors with false‑reactive results.
- Scientific contributions / talks. Lookback International Forum and Next Steps – Veronica Hoad. Mapping HTLV Positivity in Colombia: Insights from Blood Donor Surveillance (2018–2024) – Michel Garcia Otalora. How Are Blood Services Managing Dengue Spread? – Antoine Lewin. Blood donor deferral in Colombia: Transfusion‑transmitted risk criteria – Michel Garcia. Contributions of SARS‑CoV‑2 and other respiratory virus serosurveillance of blood donors to public health and EID preparedness – Mars Stone & Marion Lanteri.
Virology
- The HBV infection vaccine breakthrough assessment project continues with the recent inclusion of HBV genotype F samples. In vitro neutralization testing is closed to completion.
- Characterisation and follow-up of occult HBV infection (OBI) project. Final analysis of the genetic data has been completed. Extension of the study to cytokines/chemokines markers is discussed to terminate the study.
- Characterisation of a complex HBV surface protein variant leading to HBsAg false-negative reactivity (35th Regional ISBT Congress 2025).
- Assessment of the need for anti-HCV donation testing when HCV ID-NAT is used. An agreement with corporate partners has been finalized and the study has commenced.
- Prevalence of HBV markers in African donors: held online meetings for preparation of the project to define clear objectives and to identify potential funding sources.
- New project in development “Prevalence of Occult Hepatitis B Among Blood Donors at Cape Coast Teaching Hospital: A Pilot Study’: online meetings and request for funding to ISBT and Roche Diagnostic Solutions.
- Review of viral confirmatory testing and future donor eligibility: survey/data collection tool in development.
- Completion of the 10-year NAT survey analysis and reporting.
- Completion of an international study on emerging arboviral infections and blood safety. Manuscript submitted.
Working Party Publications
Challenges and Opportunities
Primary challenges for TTID are related to areas of focus. With so many potential threats to blood safety it is difficult for TTID to lead studies in all areas. The work that is done by TTID is primarily driven by the interests and expertise of the TTID member and their willingness to lead international collaborative projects. TTID has actively worked to provide an environment for participation of members from as many countries across the development spectrum as possible. We have also continued our successfull collaboration and engagment of corporate partners who are central to being able to address emerging infectious threats to global blood safety.
Summary
The four subgroups of TTID are actively working to document and address potential blood safety concerns. Each subgroup has leadership that drives the overall work of TTID. The TTID WP develops strong international collaborative studies that assess the extent of TTID risk and mitigation strategies. In 2025-2026, we continued this work with publication of highly relevant manuscripts and new international surveys focused on current topics of high relevance. The number of publications in this reporting year was lower than in other years. We expect the next reporting year to include a notable increase as several completed projects currently have manusciprts in development.
