Dr. Jaychandran, Dr. Krishna, Dr. Shalli, Dr. Prateek Bobhate, Dr. Samriti Gupta, Dr. Gaurav Gupta, Dr. Manish Ranjan
A Rising Concern in Global Health
Respiratory infections remain a leading cause of illness and death worldwide, especially among children under the age of five. Human Metapneumovirus (HMPV), a relatively unknown virus identified in the Netherlands in 2001, has emerged as a significant contributor to acute respiratory infections (ARI). Studies suggest that HMPVhas been responsible for respiratory illnesses globally for at least 50 years.
Global and Seasonal Patterns
While HMPV infections can occur year-round, peak incidence typically occurs in late winter and early spring in the Northern Hemisphere and during June to July in the Southern Hemisphere. The virus has four subgroups (A1, A2, B1, B2), none of which are associated with more severe symptoms than the others. Recent reports indicate a rise in HMPV infections in China, especially in the northern regions, with children aged 14 and under being most affected.
The Indian Scenario
HMPVis not new to India. India has not witnessed any sudden surge in influenza-like illnesses due toHMPV, according to the Integrated Disease Surveillance Programme (IDSP). However, the virus is prevalent, and cases of respiratory illnesses linked to HMPVhave been reported in several states. In India, a recent study conducted at JIPMER, Puducherry, highlighted the evolving nature of the virus. The study, which analyzed over 4,500 nasal swab samples between January 2021 and June 2024, identified novel strains A2.2.1 and A2.2.2. The study noted a significant outbreak from November 2022 to March 2023, with most cases reported in December and January.
How the Virus Spreads and Impacts the Body
HMPVspreads through respiratory droplets, close contact with infected individuals, or contact with contaminated surfaces. Once inside the body, the virus attaches to the cells of the upper respiratory tract using fusion proteins, facilitating viral entry.
Upon entry, the virus replicates and triggers both innate and adaptive immune responses. The body produces cytokines and interferons to fight the infection. However, the virus can evade the immune system by suppressing certain immune responses.
Recognizing the Symptoms
The most common symptoms include fever, nasal congestion, cough, and wheezing. In severe cases, HMPVcan cause bronchiolitis, pneumonia, and asthma exacerbations.
HMPVinfections are often indistinguishable from other respiratory viruses like RSV and influenza. The World Health Organization (WHO) defines influenza-like illness (ILI) as a sudden fever above 38°C, cough, and sore throat within the last 10 days.
The symptoms are mild in nature among most of the healthy individuals. However, certain groups of individuals are at high risk of having severe illness with HMPV like children less than 1-year, premature babies, both children and adults with chronic heart, lung and neurological diseases and immunocompromised individuals.
Diagnosis and Treatment
Molecular diagnosis by use of RT-PCR is the recommended method for diagnosis, and the results can be obtained within few hours. Currently, there is no specific antiviral treatment forHMPV. Supportive care, including the use of corticosteroids and bronchodilators to manage airway inflammation, remains the primary approach. Research on monoclonal antibodies and antiviral drugs is ongoing but has yet to yield definitive treatment options. . At present, no vaccine is currently available for the prevention ofHMPV.
Preventive Measures
The best defence against HMPVis good hygiene practices, including:
- Regular handwashing.
- Use of face masks when in crowded places
- Avoiding close contact with sick individuals.
- Covering the mouth and nose while coughing or sneezing.
- Staying home when experiencing cold-like symptoms.
Looking Ahead
Although HMPVis not as well-known as RSV or influenza, it poses a similar threat, particularly to vulnerable populations like young children, older adults, and immunocompromised individuals. Continued surveillance and research are essential to better understand the virus and develop effective vaccines and treatments. Public health campaigns promoting preventive measures could significantly reduce the spread of this emerging respiratory pathogen.
| Human metapneumovirus summary | ||
| Human Metapneumovirus (HMPV), a paramyxovirus causing acute respiratory infections.Worldwide distribution: Primarily affecting children less than 5 years of age causing Bronchiolitis, Exacerbation of asthma and Pneumonia.In adults, manifests from common cold to acute respiratory distress syndrome. | Diagnosis by RT-PCR using nasopharyngeal swabs/sputum.Treatment is mostly supportiveImmunosuppressed patients may require hospitalization.Prevention is best achieved by frequent hand washing, use of masks in crowded places and cough etiquettes | |
| Preventive measures | ||
| Do’s | Don’ts | |
| Practice good hand hygiene: Wash your hands frequently with soap and water for at least 20 seconds. Use an alcohol-based hand sanitizer if soap and water are not available. | Don’t share personal items: Avoid sharing utensils, cups, and towels with others. | |
| Cover your mouth and nose with a tissue or your elbow when coughing or sneezing. Dispose of used tissues immediately and wash your hands. | Don’t touch your face with unwashed hands: Avoid touching your eyes, nose, and mouth with unwashed hands. | |
| Avoid close contact with sick individuals: consider wearing mask | Don’t self-medicate: Avoid taking over-the-counter medications without consulting a doctor. | |
| Stay home if you’re sick: consider wearing mask | Don’t ignore worsening symptoms: If your symptoms worsen or you experience new symptoms, seek medical attention promptly. | |
| Stay hydrated: Drink plenty of fluids to prevent dehydration. | Don’t spread misinformation and panic | |
| Clean and disinfect frequently touched surfaces like doorknobs, light switches, and countertops. | ||
| Seek medical attention if symptoms worsen: If you experience severe symptoms, such as difficulty breathing, high fever, or wheezing, seek medical attention immediately. | ||
| Strengthen your immune system: Maintain a healthy lifestyle by eating a balanced diet, getting enough sleep, and exercising regularly. | ||
| Stay informed: Stay up-to-date on the latest information about HMPV from reliable sources | ||
(The authors are Dr. Jaychandran, Postgraduate Resident; Dr. Krishna, Postgraduate Resident; Dr.Shalli, Assistant Professor, Department of Community Medicine, Dr. Prateek Bobhate, Additional Professor, Department of Community Medicine; Dr.Samriti Gupta, Associate Professor, Department of Paediatrics; Dr. Gaurav Gupta, Associate Professor, Department of Internal Medicine; and Dr. Manish Ranjan, Assistant Professor, Department of Microbiology, AIIMS Jammu)