Detection of <em>Rotavirus</em>, <em>Norovirus</em>, and <em>Astrovirus</em> Causing Acute Diarrhoea in Children by Multiplex PCR in a Tertiary Care Hospital.

Objective: To evaluate the use of a multiplex real-time polymerase chain reaction (RT-PCR) test in detecting three viruses namely Rotavirus, Norovirus (genotypes 1 and 2), and Astrovirus that cause gastroenteritis in children under the age of five years.
Study Design: A cross-sectional study. Place and Duration of the Study: Department of Virology, Armed Forces Institute of Pathology (AFIP), Rawalpindi, Pakistan, from January to July 2023.
Methodology: A total of 87 children having acute diarrhoea and less than 5 years of age were included in this study from the outpatient clinic. Multiplex PCR was performed for the detection of three viruses: Rotavirus, Norovirus, and Astrovirus in stool samples of patients using a commercially available PCR kit. The data were analysed using Statistical Package for Social Sciences (SPSS) version 27:00.
Results: Out of total 87 children, aged 2.5 ± 1.5 years, 56 (64.3%) were positive for multiplex RT-PCR and 31 (35.6%) were negative. Rotavirus was identified in 24 (27.5%) children as the most common cause of acute diarrhoea, followed by Norovirus in 20 (22.9%), and Astrovirus in 7 (8%) patients, while co-infection with multiple viruses occurred in 5 (5.7%) of the cases.
Conclusion: This study revealed viral aetiology as a significant cause of acute diarrhoea in children. Multiplex PCR in the healthcare system can make it easier to identify, treat, and control the upsurge of diarrhoea. Prompt diagnosis of viral causes can lead to the prevention of unnecessary use of antibiotics.
Key Words: Multiplex polymerase chain reaction, Rotavirus, Norovirus, Astroviridae, Diarrhoea.