Absence of detectable monkeypox virus DNA in 11,000 English blood donations during the 2022 outbreak

BackgroundA large, worldwide outbreak of mpox (formerly referred to as monkeypox) involving mainly men who have sex with men commenced in May 2022. We evaluated the frequency of positivity for the causative agent, monkeypox virus (MPXV), in blood donations collected in August 2022, during the outbreak period in Southern England. Methods/MaterialsThe sensitivity and specificity of an MPXV-specific PCR and a generic non-variola orthopoxvirus (NVO) PCR were evaluated using samples from mpox cases and synthetic DNA standards. Residual minipools from nucleic acid testing were obtained from 10,896 blood donors in Southern England, with 21% from London. ResultsMPXV and NVO PCRs were both capable of detection of single copies of target sequence with calculated limits of detection (LOD)(90) s of 2.3 and 2.1 DNA copies and analytical sample sensitivities of 46 and 42 MPXV DNA copies/ml, respectively. 454 minipools produced from 10,896 unique donors were assayed for MPXV DNA by both methods. No positive minipools were detected by either PCR. ConclusionsAlthough blood donors are unrepresentative of the UK population in terms of MPXV infection risk, the uniformly negative MPXV DNA testing results provide reassurance that MPXV viraemia and potential transmission risk were rare or absent in donors during the outbreak period. Minipools from blood donors allow rapid implementation of large-scale population-based screening for emerging pathogens and represent an important resource for pandemic preparedness.

Automated summary

A large outbreak of monkeypox, mainly among men who have sex with men, occurred worldwide from May 2022. This study evaluated the presence of the causative agent, monkeypox virus (MPXV), in blood donations collected in Southern England during the outbreak in August 2022. The results showed no detection of MPXV in the blood donations, indicating a low risk of virus transmission among blood donors during the outbreak.