Work

Molecular and epidemiological characterization of human parainfluenza virus Type 4b in children with respiratory illnesses in Cholistan, Pakistan

Year: 2025

Type: article

Abstract: • This is the first molecular and epidemiological study to characterize Human Parainfluenza Virus Type 4b (HPIV4b) in pediatric respiratory infections in Cholistan, Pakistan, providing critical insights into a previously understudied region. • Whole-genome and HN gene analyses demonstrated that HPIV4b in Cholistan is evolutionarily stable, with no evidence of recombination and occurring predominantly under purifying selection, suggesting only limited antigenic drift. • All the HN gene sequences from Cholistan share close evolutionary relationships with strains from Japan, China, and the USA. • Glycosylation site analysis showed conserved N- and O-glycosylation patterns in HN and F proteins, while entropy analysis revealed low genetic variability confirming HPIV4b’s antigenic stability. • HPIV4b was identified as a significant cause of acute respiratory illness in children under five, underscoring a need for its inclusion in routine diagnostic panels and national respiratory virus surveillance programs. Human parainfluenza virus type 4b (HPIV-4b) is an under-recognized but clinically significant pathogen associated with acute respiratory tract infections (ARTIs), particularly in young children. Its molecular and epidemiological profiles remain poorly characterized in resource-limited Pakistani settings. This study aimed to investigate the prevalence, clinical associations, and molecular characteristics of HPIV-4b among children under five years of age presenting with respiratory illnesses in the Cholistan region of Pakistan. Between October 2022 and March 2025, 200 nasopharyngeal swabs were collected from pediatric patients exhibiting respiratory symptoms. Samples were screened for HPIV-4b using multiplex reverse transcriptase PCR (mRT-PCR). Positive samples were subjected to further molecular analysis of the hemagglutinin-neuraminidase (HN) and fusion (F) genes. Selected strains underwent sequencing and phylogenetic analysis. HPIV-4b was detected in 80 (40 %) of the children, with the highest positivity observed in infants aged 0–1 year. A higher infection rate was noted in male children (62.5 %). Clinical features associated with infection included fever, barking cough, and wheezing (p < 0.05). The virus was more prevalent among children from socioeconomically disadvantaged families and those with a family history of pulmonary disorders. Sequence data revealed high similarity between local strains and international isolates from Japan, the USA, and China. Phylogenetic analysis indicated the circulation of genetically distinct but evolutionarily conserved HPIV-4b lineages. This is the first molecular and epidemiological characterization of HPIV-4b in Pakistani children, highlighting its clinical relevance and genetic diversity. The findings underscore a need for early diagnosis and sustained genomic monitoring.

Source: Infectious Diseases Now

DOI: 10.1016/j.idnow.2025.105218

Authors: Aqeela malik, Fatima Ali, Waseem Safdar, Muhammad Tariq Saeed, Muhammad Tariq Navid, Farheen Ansari

Institutions: University of Lahore, National University of Medical Sciences, Shandong University of Technology, University of Karachi

Language: English

Topic: Respiratory viral infections research

Subfield: Epidemiology

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: hybrid

Estimated APC paid: $1,640