Prevalence of human T-cell lymphotropic virus type 1 or 2 among blood donors screened at the New Zealand Blood Service: An observational study, 2001-2024.

OBJECTIVE

To investigate prevalence of Human T-cell Lymphotropic Virus type 1 or 2 (HTLV-1/2) using the New Zealand Blood Service (NZBS) data, to inform whether further HTLV-1/2 prevalence study may be required, in the context of drivers of the inequities in lung cancer for Māori (the Indigenous population).

METHODS

This observational cross-sectional study used the NZBS data of all blood donors nationwide (01/01/2001-30/06/2024). Prevalence overall and by ethnicity was calculated as the number of confirmed HTLV-1/2 positive cases per 10,000 donors.

RESULTS

Of 679,946 new donors over the 23.5 years, 25 HTLV-1/2 positive cases were identified. The overall prevalence of HTLV-1/2 in New Zealand was 0.4 cases per 10,000 donors, highest among Middle Eastern, Latin American and African ethnicity (six cases per 10,000 donors), with no positive cases in Māori and Pacific donors. Among the positive cases, the highest proportions were seen separately for those aged 25-34, females, of New Zealand European ethnicity, resident in Auckland, and born in India, compared to their counterparts.

CONCLUSIONS

Prevalence of HTLV-1/2 infection among blood donors in New Zealand was very low, with no evidence of infection among Māori and Pacific donors, suggesting that a wider HTLV-1/2 seroprevalence study was unlikely to be necessary.