P004 Retrospective analysis of deceased donor samples for ZIKA virus infection in high-risk population, a three-year study

The recent epidemic of Zika Virus in the United States has necessitated screening for the presence of this agent in high-risk transplant solid organ donors to avoid the transmission to potential recipients. In this study, we performed a retrospective analysis of Cadaver Donors from Auxilio Mutuo Hospital (HAM) in Puerto Rico. One hundred fifty-six (156) serum samples from Deceased Donors were obtained from Puerto Rico. Aliquots of serum, were maintained at −20°C since collection. There were 38 samples from 2014, 62 from 2015, and 56 from 2016. These samples were tested with the RealStar® Zika Virus RT-PCR Kit U.S.® kit (Altona Diagnostics), and Anti-Zika Virus ELISA IgG and IgM kits (EUROIMMUN). These assays were validated with a separate group of freshly obtained Zika-positive samples from an ambulatory clinic at HAM. Of the 156 total deceased donor specimens retrospectively tested, none were positive for PCR, 2 were positive for IgM, and 22 were positive or borderline for IgG. The breakdown over the 3-year period indicated an increase in long-term exposure, as indicated by the increase in IgG positive samples. In 2014, only 5.2% were positive. However, by 2015 19.4% of the samples were positive. This indicates that almost 20% of the Deceased Donors tested had some contact with the Zika Virus (or a related Flavivirus, such as Dengue or West Nile). Of the positive IgG samples, only 2 were positive for IgM, indicating the exposure was likely more than 3months prior. The results of the PCR study were not surprising, as we have seen in our laboratory, the long-term storage of serum for later RNA-based PCR testing has been unsuccessful. Zika testing utilizing PCR-based assays in conjunction with serological assays in areas of known infection is essential, especially when servicing solid organ transplant programs. The use of donors potentially infected with Zika virus could have a significant impact in transplant success as there are some indications that immunocompromised individuals may develop more severe symptoms or illnesses. The correct storage of serum samples is crucial to obtain reliable results of this test