Incidence and aetiology of viral infections among African newborns with suspected bacterial sepsis
Uduak Okomo, MBBCh, FWACP, MSc, PhD
BACKGROUND: Infections are the third most common and preventable cause of neonatal deaths globally; an estimated 600,000 infection-related neonatal deaths occur annually, the majority of which take place in West and Central Africa. Despite this knowledge, our understanding of the pathogens causing infections in these high-burden settings is limited. GAP: Accurate determination of the causes of neonatal infection depends on isolation of bacteria by blood culture; yet only 5 – 25% of neonatal blood cultures yield bacterial isolates. The aetiology of over 75% of suspected neonatal infection cases that report to the hospital remains therefore unknown and may represent unrecognized viral infections. HYPOTHESIS: In our cohort of sick Gambian newborns admitted with possible serious bacterial infections, a large proportion of blood culture negative cases are caused by viruses. METHODS: This was a laboratory-based descriptive study in which we will analyze archived nasopharyngeal samples collected previously as part of a matched case control study to describe the aetiology of invasive bacterial infections in Gambian newborns. Samples were collected from 203 sick newborns with possible serious bacterial infection and an equal number of age- and community-matched healthy controls. RESULTS: Four (2%) of the 203 sick newborns and three (1.5%) of the healthy controls had nasopharyngeal samples positive for respiratory viruses respectively. The odds of viral infection were among sick newborns was 30% higher than healthy controls (OR 1.3, 95% CI 0.22 – 9.10; P=0.7055). The following viruses were identified: Influenza A, Parainfluenza virus 3; rhinovirus and endemic coronavirus. All but one of the viral infections were single infections. All sick newborns had mixed viral-bacterial infection, and 75% (3/4) of these babies died on admission compared to 29% (41/141) of sick newborns with only bacterial infection/carriage, and 26% (15/58) of those with negative nasopharyngeal swabs. IMPACT: We observed a very low prevalence of respiratory viral infection among sick newborns with possible serious bacterial infection in our setting, with no significant difference between the prevalence of viral infection among sick newborns and healthy age- and communitymatched controls. However, sick newborns with mixed viral-bacterial infection had worse outcomes compared to those with only bacterial infection or infection at all. The diagnosis of a respiratory viral infection should be considered when sick newborns receiving treatment for suspected or confirmed sepsis/pneumonia do not improve on antibiotic treatment. Early diagnosis is also necessary to inform modalities as well as antimicrobial stewardship initiatives in neonatal units by facilitating the withholding or discontinuing of unnecessary antimicrobial therapy.