Hyderabad: Experts have clarified that the ongoing Human Metapneumovirus (HMPV) outbreak in China is not new. In fact, this virus has been circulating for the past eight years.
According to Dr. Kiran Madhala, the convener of the Indian Medical Association-Telangana Scientific Committee, HMPV is a single-stranded RNA virus. It was reclassified in 2016 into the Metapneumovirus genus within the Pneumoviridae family. HMPV has two main subtypes, A and B, which are further divided into six genotypes. Among these, the A2c and B2 genotypes are the most common. The A2c variant, identified by a unique 111-nucleotide duplication, was the dominant strain worldwide until 2022.
Dr. Kiran also highlighted that the virus caused significant global impact in 2018, leading to 1.1 crore (11 million) cases. The hospitalisation rate stood at five percent, while the fatality rate was approximately one percent.
HMPV infections typically present with symptoms such as fever, cough (often with mucus), and pneumonia. Compared to other respiratory viruses like COVID-19 and RSV, HMPV shows a lower incidence of fever and cough but a higher likelihood of pneumonia. The positivity rate for HMPV infections varies, ranging from seven percent to 40 percent in studies conducted in China in 2022. Children between the ages of one and four are particularly vulnerable to this virus.
Experts suggest that the COVID-19 pandemic might have indirectly increased susceptibility to HMPV. The reduced exposure to the virus during the pandemic, weaker maternal antibody protection, and a larger pool of susceptible individuals are likely factors contributing to the current rise in cases. However, analysis of outbreaks in China from 2017 to 2023 confirms that this virus has been present for several years.
