# 691. Epidemiology of Viral Respiratory Infections in Pediatric Transplant: Initial results from the Viral Infections in Pediatric Transplant Recipients (VIPER) Study

## TL;DR

This study investigates the frequency and impact of respiratory viral infections in children who have received transplants, finding that rhinovirus/enterovirus is the most common virus and may predict future infections.

## Contribution

The VIPER study provides new prospective data on the epidemiology of respiratory viral infections in pediatric transplant recipients.

## Key findings

- Rhinovirus/enterovirus (RhV/EV) was the most frequent virus detected in both hematopoietic cell and solid organ transplant recipients.
- Baseline RhV/EV predicted subsequent RhV/EV respiratory viral infections (OR:2.9).
- Upper respiratory tract infections were more common than lower respiratory tract infections in both transplant groups.

## Abstract

Respiratory viral infections (RVIs) cause substantial morbidity in pediatric transplant recipients. Previous efforts to establish the epidemiology of RVIs are mainly retrospective, with limited evaluation of association between pre-transplant screening of respiratory viruses and future RVIs. The VIPER study is a prospective, multicenter cohort study investigating the epidemiology and impact of RVIs in these patients.Figure 1Clinical Presentation of Respiratory Viral Infections Post Transplant

Clinical Presentation of Respiratory Viral Infections Post Transplant

Patients undergoing Hematopoietic Cell Transplantation (HCT) and Solid Organ Transplant (SOT) at 26 US institutions were enrolled at transplant and monitored for RVIs for a year. Nasal swabs (NS) were collected at baseline and first clinical RVI, and clinical data extracted from medical records. Baseline NS were tested for viruses using standard real time PCR methods (OpenArray, ThermoFischer Scientific) and compared with clinical PCR results at first RVI. We summarize the preliminary clinical data and analyze the association between baseline testing and the first RVI with univariate logistic regression. The study is conducted through the Pediatric Infectious Diseases Transplant Network (PIDTRAN).Figure 2Respiratory Viruses Detected at Baseline and at First Respiratory Viral Infection Episode

Respiratory Viruses Detected at Baseline and at First Respiratory Viral Infection Episode

157 HCT and 174 SOT recipients were included. Demographic and transplant characteristics are described in Table 1. HCT patients had more RVIs vs SOT (77% vs 69%). Median time from transplant to first RVI was 99 days for HCT and 112 days for SOT. Upper respiratory tract infections (URTI) were common in both groups (Figure 1) but more SOT than HCT recipients progressed to lower respiratory tract infection (LRTI). Rhinovirus/enterovirus (RhV/EV) were the most frequent viruses in HCT and SOT, both at baseline and first RVI (Figure 2). Among LRTI, the most frequent viruses were RhV/EV (48%), Adenovirus (16%) and RSV (13%). Only baseline RhV/EV predicted RhV/EV at first RVI (OR:2.9, CI:1.2-6.9, p=0.02).

Many transplant recipients carry respiratory viruses at the time of transplant. Most post- transplant RVIs were URTI. RhV/EV were the most frequent virus detected overall, including in LRTI. RhV/EV at baseline predicted subsequent RhV/EV RVI. No other virus demonstrated this association. Analysis is limited by the current sample size, but the continuing accrual will allow for a more robust analysis.

Lara A. Danziger-Isakov, MD, MPH, AiCuris.: Grant/Research Support|Ansun BioPharma: Grant/Research Support|Astellas Pharma Global Development, Inc: Advisor/Consultant|Astellas Pharma Global Development, Inc: Grant/Research Support|kamada: Advisor/Consultant|Merck Sharp & Dohme Corporation: Grant/Research Support|Pfizer (Any division): Grant/Research Support|Takeda Pharmaceuticals: Grant/Research Support