Resources

Published 1 October 2025

• OPTN Comment

The International Society for Heart and Lung Transplantation (ISHLT) welcomes the opportunity to review the OPTN Proposal “Require West Nile Virus Seasonal Testing for Donors.”

West Nile virus (WNV) is endemic in the United States where it has been found in all 50 states and is also prevalent across the globe. WNV is challenging to detect clinically in potential donors and can be transmitted via solid organ transplantation and blood transfusion. Proven effective treatment or vaccination for WNV do not exist. Testing is currently done voluntarily by some Organ Procurement Organizations (OPOs), but the significant morbidity and mortality associated with WNV in solid organ transplant recipients justifies seasonal testing for all organ donors.

The data shows that most WNV cases occur between July 1 and October 31, and this supports the recommendation for seasonal testing only. This will help keep costs manageable for OPOs and transplant hospitals. Seasonal testing will avoid periods of very low pre-test probability and therefore will reduce the risk of false positive tests. Additionally, the non-insignificant burden of disease in June warrants consideration of utilizing a June 1 to October 31 testing period.

A clear operational outline is recommended for OPOs and transplant hospitals. We agree with the recommended testing modality of WNV RNA detection via NAT along with requiring testing within 7 days of organ recovery. The high specificity of NAT should also minimize the risk of false positives.

We agree with the decision for policy review at 1- and 2-years post implementation, and we would recommend considering additional evaluations of the policy based on future reports of WNV activity in the US based on CDC data. We also recommend consideration for OPOs to report when organs are discarded due to positive testing for WNV.

In conclusion, we support the recommendation for seasonal testing of all potential solid organ donors. The proposal is well written, and it addresses the risk of false positive testing while protecting transplant recipients from inadvertent WNV transmission. We believe that this policy will help achieve optimal transplant recipient outcomes while avoiding the imposition of excessive burdens on OPOs and transplant hospitals.