Screening for West Nile virus in organ transplantation: a medical decision analysis

The Organ Procurement and Transplant Network (OPTN) has recently announced that screening for West Nile Virus (WNV) in deceased organ donors is not recommended at this time. The purpose of this report was to examine the impact of this recommendation by using medical decision analysis. Without screening the rate of disease transmission was assumed to be the same as in donated blood with a case fatality rate of 25%. With screening we assumed the baseline screening test specificity and sensitivity to be 99.5% and 95%, respectively. The analysis was confined to heart, liver and kidney recipients. Survival probabilities and transplant rates were taken from UNOS. Annual screening could result in the loss of potentially 452.4 life years (113.8 for heart, 272.6 for liver and 66.0 for kidney). Most positive test results would be false-positive. Screening would be preferable for kidney donors in areas of high disease prevalence and high test specificity. However, for heart and liver most scenarios were associated with a net loss of life with screening, except if patients were stable on the wait list with particularly high case fatality rates from WNV. Current recommendations by OPTN that screening is not mandatory seem appropriate until further data are available.