Parainfluenza Virus Infection Factors: 18 Years’ Active Surveillance in a Pediatric Hospital

Background: Paranfluenza Virus (PIV) is an important cause of acute lower respiratory tract infection (ALRI), hospitalization and mortality in children. The aims of this study were to describe the clinical-epidemiologic pattern and infection factors associated with PIV.

Methods: Prospective, cross-sectional study of patients admitted for ALRI 2000–2017, diagnosed with respiratory syncytial virus, adenovirus, influenza or parainfluenza by fluorescent antibody (FA) or real-time polymerase chain reaction (RT-PCR) assay of nasopharyngeal aspirates.

Results: From a total of 15,451 patients included, 13,033 were tested and 45%(5831) had positive samples; RSV was predominant (81.3%,4738) all through the study period, followed by IF:7.6% (440), PIF 6.9%(402) and AV:4.3%(251). PIV followed a seasonal epidemic pattern predominantly during spring months (September- October).

The median age of cases was 8 months (IQR: 4-13 months); 54% of cases were males. The most frequent clinical presentation was bronchiolitis (61%); 53% had previous admissions for respiratory causes, 9% were readmissions. Comorbidity was found in 59.4%: recurrent respiratory disease (47.8%), congenital heart disease (5.7%), chronic neurological disease (6.5%); 8.5% were malnourished, 23% born preterm and 3.3% immunosuppressed; 23.5% had complications, 10.6% hospital acquired infections. Lethality was 3.5% (14/396).

The following were independent predictors for PIF infection: recurrent respiratory disease odds ratio (OR): 1.65 (95% CI: 1.32-2.08); p<0.001; readmissions, OR 1.95 (95% CI: 1.34-2.83); p<0.001; born preterm, OR: 1.58 (95% CI: 1.19-2.10); p=0.001.

Conclusion: Parainfluenza infection showed an epidemic seasonal pattern (September-October), with higher risk in children with recurrent respiratory disease, prematurity and previous admissions for respiratory causes.