Molecular detection of Human Metapneumovirus among geriatric patients presenting with acute respiratory tract infection in Ibadan, Nigeria

Acute respiratory tract infections (ARTIs) are among the leading causes of morbidity and mortality worldwide, and viruses are primarily responsible for these infections. The Human Metapneumovirus (hMPV) is a respiratory pathogen that was first identified in 2001 in the Netherlands, and has since been recognized as one of the major viral causes of respiratory infections. The clinical manifestations of hMPV infection are typically asymptomatic or mild in healthy adults, however, for high-risk populations, such as children less than 5 years, older people, immunocompromised individuals, and patients with underlying chronic conditions, hMPV infection can lead to severe clinical manifestations, such as pneumonia. Despite its substantial health burden, hMPV is not routinely tested for and monitored in many countries, there are also no approved vaccines or antiviral treatments, and management of the infection remains supportive. The recurrent hMPV related outbreaks in recent years and its potential to cause pandemics, particularly in the post-COVID-19 era, highlights the urgent need for improved surveillance and targeted interventions. Oropharyngeal and nasal swab samples were collected from five hundred and twenty four (524) geriatric patients comprising of outpatient individuals presenting with symptoms of acute respiratory tract infection (ARTI) and those attending the clinic for routine health checks recruited as asymptomatic controls from the period of April 2024 to May 2025. The samples were tested for the presence of Human metapneumovirus using a semi-nested Polymerase chain reaction targeting the Nucleoprotein (N) gene of the virus. Thirty six (6.9%) of the 524 samples were positive for Human Metapneumovirus infections with a significantly (p = 0.004) higher rate among symptomatic participants (5.2%). The difference in the rate of hMPV positivity between age groups and gender was not statistically significant (p = 0.707; p = 0.344 respectively). The three symptoms most commonly reported among hMPV positive cases in our study were cough (30.6%), fever (25%), and headache (25%); however the comparison of clinical symptoms across all the participants showed that chills and sore throat were the only symptoms statistically significant with hMPV positivity (p = 0.006; p = 0.023 respectively). HMPV positivity peaked during the month of July with the highest number of infections detected in symptomatic and asymptomatic individuals within that month. This study highlights the impact of hMPV among the geriatric population in Ibadan, Nigeria, indicating a necessity for more accurate and dependable estimates of the incidence of hMPV-associated disease in the older adult population.