Pathogenic Role of Human Rhinovirus Mono-Infection in Pediatric Lower Respiratory Tract Infection

Abstract

Background and objective Human rhinovirus (HRV) is one of the leading causes of pediatric respiratory tract infection with a prevalence rate of 30-50%, mostly affecting children below five years of age and causing a substantial amount of economic loss. In children, it can alone or as a co-infection, cause a wide range of symptoms from mild to life-threatening ones. With the above background, the current study was carried out to emphasize the role of HRV mono-infection in pediatric acute respiratory tract infections by correlating clinical and molecular laboratory findings. Methods This study was carried out in a tertiary care teaching hospital over a duration of four years (March 2019-October 2023). Children up to 14 years of age visiting the outpatient department or admitted to the ward with diagnoses of acute respiratory tract infections (ARTIs) were included. The clinical and laboratory data were retrieved and analyzed. A nasopharyngeal swab (NPS) or throat swab (TS) was collected and sent to the Microbiology laboratory maintaining the cold chain. Nucleic acid was extracted and subjected to multiplex real-time polymerase chain reaction (RT-PCR). Result Of the 245 samples tested for the respiratory viral pathogen, 52 samples tested positive for HRV, of which 27 had HRV mono-infection. The clinico-demographic details of these 27 patients were studied in detail. The majority of the cases (24/27; 88.8%) were less than five years of age. Fever and shortness of breath were the most consistent symptoms in all. Nineteen (19/27; 62.9%) HRV mono-infection cases had underlying co-morbidities, all requiring respiratory support. The HRV mono-infection cases either developed bronchiolitis, lower respiratory tract infection, or pneumonia. All mono-infection cases had cycle threshold value (Ct) < 25, while the Ct value of HRV was > 30 in co-infection with other viruses. Conclusion Mono-infection of HRV in under-five children with underlying comorbidities and a lesser Ct value indicates severe disease manifestation and should be dealt with more cautiously.

Keywords: cycle threshold (ct) value; human rhinovirus; lower respiratory tract infection; mono-infection; pathogen; pediatric.

Figure 1. Details of the positive respiratory pathogens isolated

Influenza A (IAV), influenza B (IBV), influenza A [IAV(H1N1)sw1], parainfluenza virus (HPIV-1, HPIV-2, HPIV-3, HPIV-4), human coronaviruses (HCoV), human rhinovirus (HRV), human bocavirus (HBoV), human respiratory syncytial virus (HRSV A & B), adenovirus (HAdV A & B), human metapneumovirus (HMPV A & B), human parechovirus (HPeV), Epstein-Barr virus (EV)

Figure 2. (a) HRV mono-infection. (b) HRV + EV co-infection

HRV - Human rhinovirus, EV - Epstein-Barr virus