Unrecognized Viral Respiratory Tract Infections in Premature Infants during their Birth Hospitalization: A Prospective Surveillance Study in Two Neonatal Intensive Care Units

Abstract

Objective We sought to determine the frequency and effects of nosocomial respiratory viral infections (RVIs) in premature neonates, including those who may be asymptomatic. Study Design We performed a year-long surveillance for RVIs in infants <33 weeks gestational age admitted to two Syracuse neonatal intensive care units (NICUs). Infants were enrolled within 3 days of NICU admission and were sampled for RVIs until discharge using a multiplex PCR assay capable of detecting 17 different respiratory viruses or subtypes. Results 26 of 50 prematurely born infants (52%) tested positive for a respiratory virus at least once during their birth hospitalization. Testing positive for a respiratory virus was significantly associated with longer length of stay (70 days vs. 35 days, p = 0.002) and prolonged ventilatory support (51 vs. 13 days, p = 0.002). Infants who tested positive for a respiratory virus during their birth hospitalization had more than twice the rate of developing bronchopulmonary dysplasia (BPD; p < 0.05). Conclusion Nosocomial RVIs were frequent in our study population, despite the absence of clinical indicators of illness. Length of hospital stay was significantly longer and a diagnosis of BPD was more common in those premature infants who had respiratory viruses detected.

Outcomes of Nosocomial Viral Respiratory Infections in High-Risk Neonates

“…Recent studies have highlighted that either parallel screening at the time of sepsis concerns, or routine surveillance monitoring, identify VRTI in 8 to 52% of infants in the NICU [12][13][14] . Our study has focused on symptomatic infants with a suspected VRTI and identified the most dominant pathogen was…”

“…Nosocomial VRTIs are often unrecognised or clinically underdiagnosed in the NICU 12,13 with up to 52% of admissions testing positive for viral DNA by PCR 14 . Therefore, it is plausible that VRTIs acquired during the NICU period could worsen BPD in preterm infants although previous studies have mostly been small observational studies 12,13,[15][16][17][18][19] .…”

The impact of respiratory viruses on lung health after preterm birth

“…Although bacterial outbreak has long been the main focus of nosocomial infection during the neonatal period, previous studies have demonstrated that viral outbreaks can contribute to an equivalent level of mortality (6.4% vs. 7.17% respectively) [33,34]. The role of viruses in nosocomial infection has become increasingly recognised, with several studies showing that 20 to 50% of very preterm infants, born at ≤ 32 weeks’ gestation, acquired a nosocomial infection with a respiratory virus during their birth hospitalisation, often in the absence of clinical indicators of respiratory illnesses [35–37]. The detection of asymptomatic respiratory viruses was associated with deleterious outcomes, such as prolonged hospitalisation, increased number of clinical deterioration events as well as a greater requirement and longer duration of supplemental oxygen and ventilatory support [33,34,36,37].…”

“…The role of viruses in nosocomial infection has become increasingly recognised, with several studies showing that 20 to 50% of very preterm infants, born at ≤ 32 weeks’ gestation, acquired a nosocomial infection with a respiratory virus during their birth hospitalisation, often in the absence of clinical indicators of respiratory illnesses [35–37]. The detection of asymptomatic respiratory viruses was associated with deleterious outcomes, such as prolonged hospitalisation, increased number of clinical deterioration events as well as a greater requirement and longer duration of supplemental oxygen and ventilatory support [33,34,36,37]. In addition, the risk of developing a BPD diagnosis was more than two-times higher among infants with detected respiratory viruses during their birth hospitalisation [36,37].…”

“…The detection of asymptomatic respiratory viruses was associated with deleterious outcomes, such as prolonged hospitalisation, increased number of clinical deterioration events as well as a greater requirement and longer duration of supplemental oxygen and ventilatory support [33,34,36,37]. In addition, the risk of developing a BPD diagnosis was more than two-times higher among infants with detected respiratory viruses during their birth hospitalisation [36,37]. Collectively, such findings may advocate for more comprehensive routine testing for respiratory viruses in preterm infants during the neonatal hospitalisation…”