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Journal of Drug Delivery and Therapeutics

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Recent outbreaks of Human Metapneumovirus (HMPV): Prevention, Diagnosis and Therapeutic insights

Trilochan Satapathy ¹*, Abhisek Satapathy ², Abinash Satapathy ³, Neha Yadav ³, Manisha Chandrakar ⁴, Kunal Chandrakar ⁴

¹Columbia Institute of Pharmacy, Raipur, Vill-Tekari, Near Vidhansabha, Raipur-493111, Chhattisgarh, India

² Pt J.N.M. Medical College, Jail Rd, opp. Central Jail, Moudhapara, Raipur-492001, Chhattisgarh, India

³ College of Veterinary Science and Animal Husbandry, Anjora, Durg-491001, Chhattisgarh, India

⁴ University College of Pharmacy, Chhattisgarh Swami Vivekananda Technical University, Bhilai-491107, Chhattisgarh, India

 

 

Introduction:

 

Human metapneumovirus (HMPV) is a negative-sense, single-stranded RNA virus from the Pneumoviridae family.¹ The respiratory virus belongs to the Avian metapneumovirus subgroup C and affects mostly the upper and lower respiratory tracts. It was discovered in 2001 by a group of Dutch researchers led by Dr. R. van den Hoogen.² The virus was discovered during an examination into respiratory illnesses in young children. This discovery was made possible by molecular techniques, specifically reverse transcription polymerase chain reaction (RT-PCR), which enabled scientists to identify and isolate the virus from respiratory samples.³ Prior to the identification of HMPV, severe respiratory illnesses in children and adults were frequently attributed to more well-known viruses such as Respiratory Syncytial Virus (RSV), influenza, and adenoviruses. However, a considerable proportion of these instances could not be explained, encouraging further investigation into unknown infections. Following its discovery, HMPV was rapidly identified as a major pathogen leading to respiratory diseases, particularly in newborns and the elderly.⁴ It is currently recognized as one of the leading causes of viral respiratory tract infections globally. Over the last two decades, multiple investigations have established the incidence of HMPV in both hospitalized and outpatient settings.⁵ The virus circulates periodically, peaking in late winter and spring, as do other respiratory viruses such as RSV and influenza. HMPV is a member of the Paramyxoviridae family, specifically the Metapneumovirus genus, and is known to cause mild to severe respiratory infections, especially in small children, the elderly, and immunocompromised people.⁶ It is a leading cause of acute respiratory illness worldwide, particularly during the winter months when respiratory infections are more common. HMPV frequently produces normal cold symptoms such as coughing, fever, nasal congestion, and wheezing, but it can also cause bronchitis and pneumonia in severe cases. In susceptible individuals with underlying medical issues, HMPV infection can result in mortality.⁷ The Human Metapneumovirus (HMPV) is already in circulation worldwide, including India, as of December 2024.

Structural architecture of Human Metapneumovirus (HMPV):

HMPV has an enclosed structure and seems pleomorphic, which means it can take on a number of shapes, including spherical or slightly elongated. HMPV particles are frequently spherical or oval in shape, with a smooth or slightly jagged appearance due to glycoprotein spikes on the viral surface, when seen under an electron microscope. The spikes are visible on the exterior of the membrane, but the RNA genome is located inside. The viral particle typically measures 150-200 nm in diameter. The virus's surface is covered in spikes or glycoproteins, which are critical to its ability to infect host cells.⁸ These glycoproteins include the Fusion (F) protein, which is responsible for the virus's ability to fuse with host cells. Attachment protein (G) helps the virus connect to receptors on the surface of host cells HMPV's genome is made up of single-stranded RNA, which is typical of viruses in the Paramyxoviridae family.⁹

 

 

 

 

Figure 1: Electron Microscopic structure of Human Metapneumovirus (HMPV)

 

 

Epidemiology:

According to research, HMPV is a prevalent cause of respiratory infections in young children, particularly those under the age of five, as well as those with underlying health issues, such as the elderly and immunocompromised individuals. While HMPV is not as well known as RSV or influenza, it is responsible for a large number of hospitalizations and can cause consequences such as pneumonia and respiratory failure, particularly in vulnerable groups.¹⁰

Characteristics and Classification of Human Metapneumovirus (HMPV):

Human Metapneumovirus (HMPV) is genetically and structurally similar to RSV, but it is a separate virus with a unique genomic structure and antigenic profile. HMPV, like RSV, causes infections in the lower respiratory tract, which can result in bronchiolitis, pneumonia, or croup. However, HMPV's clinical presentation can vary greatly, with some people exhibiting mild cold-like symptoms and others developing severe respiratory distress.¹¹

 

 

Table 1: Comparison between normal common cold and HMPV-infected common cold: ^{12, 13, 14, 15}

Feature	Normal Common Cold	HMPV-Infected Common Cold
Causative Virus	Rhinoviruses and other moderate respiratory viruses are the most common causes.	Caused by Human Metapneumovirus (HMPV), a member of the Paramyxoviridae family
Age Group Affected	Primarily affects children, but can also occur in adults.	Primarily affects young children, elderly, as well as  immunocompromised individuals.
Incubation Period	1–3 days	3–6 days
Symptom Onset	Mild symptoms such as sneezing, a sore throat, and a runny nose appear gradually.	Gradual onset, but may involve more severe respiratory symptoms (e.g., coughing and wheezing).
Symptoms	- Nasal congestion   - Sneezing   - Sore throat   - Mild cough   - Low-grade fever (sometimes)	- Nasal congestion   - Runny nose   - Cough   - Wheezing   - Fever (common)   - Sore throat (less common)
Fever	Uncommon or mild, typically below 102°F (38.9°C).	Sometimes present, can range from mild to moderate.
Cough	Usually mild and dry.	Can be more pronounced, sometimes wet or with wheezing.
Severity of Symptoms	Generally mild, self-limiting (lasts 7–10 days).	Can be mild to moderate; can escalate to bronchiolitis or pneumonia, particularly in vulnerable groups.
Duration of Illness	7–10 days	7-14 days or longer in severe cases, particularly in youngsters and the elderly.
Complications	Rare, generally resolves without complications.	Can result in problems such as bronchiolitis, pneumonia, and respiratory distress.
Transmission	Highly contagious, transmitted mostly by respiratory droplets and contact with infected surfaces.	Highly contagious, similar to the common cold, transmitted primarily by respiratory droplets and contact with infected surfaces.
Seasonality	Typically occurs year-round, with peak seasons in the fall and spring.	Seasonal, with peak circulation during late winter and early spring.
Diagnosis	Clinical diagnosis based on symptoms. Often confirmed by rapid tests or viral culture.	Diagnosed by Polymerase Chain Reaction (PCR) or viral culture from respiratory specimens.
Treatment	Symptomatic treatment (e.g., rest, hydration, over-the-counter (OTC) medications like decongestants, and analgesics).	No specific antiviral treatment; Only supportive care (hydration, oxygen, sometimes hospitalization in severe cases).
Risk of Severe Disease	Very low; complications are also rare.	Higher risk of severe respiratory illness, especially in infants, elderly, & immunocompromised individuals.
Vaccine Availability	No vaccine, but some protection from prior exposure and seasonal immunity.	No vaccine currently available, but research is ongoing.
Prevention	Good hygiene (hand washing), avoiding contact with infected individuals, and rest.	Same prevention as common cold, and additional focus on protecting high-risk groups (young children, elderly).

 

 

Mode of Transmission of HMPV Virus in Humans:

Human metapneumovirus (HMPV) is a respiratory virus that mostly affects the upper and lower respiratory tracts. The most prevalent form of transmission is by respiratory droplets produced when an infected person coughs, sneezes, or speaks. These droplets can land in people's mouths, noses, or eyes, spreading the infection. HMPV can also be transmitted through direct contact, such as shaking hands with an infected person or touching surfaces contaminated with respiratory secretions (doorknobs, shared objects).¹⁶ Afterward, touching the face, particularly the nose, mouth, or eyes, can help the virus enter the body.  In rare situations, the virus may spread via small aerosolized particles, which are lighter and can stay suspended in the air for a longer period. This method of transmission is more common in packed, enclosed places, but it is less thoroughly studied than droplet transmission. HMPV can live on surfaces for a while, and people who touch contaminated surfaces may get the virus by touching their mouth, nose, or eyes. After exposure, symptoms usually manifest within 3 to 6 days, and infected people might be contagious for several days before and after symptoms appear, especially during the peak of their illness.¹⁷

General Sign and symptoms of Human Metapneumovirus (HMPV):

HMPV can induce a wide spectrum of respiratory symptoms, from mild to severe. Symptoms of the upper respiratory tract include runny nose, cough, sore throat, and nasal congestion. Lower respiratory symptoms include wheezing, trouble breathing, and signs of pneumonia. Severe instances have been recorded, particularly in small children and the elderly, and the virus can cause bronchiolitis, pneumonia, and respiratory failure.¹⁸

Post invasion consequence of HMPV Virus in children and elderly people:

Human Metapneumovirus (HMPV) infection can cause a variety of respiratory problems, especially in vulnerable populations including children and the elderly. While most people recover from HMPV infection with supportive treatment, the post-infection repercussions can be severe and long-lasting in some cases, particularly in the very young and elderly.¹⁹ These implications differ according to the patient's overall health, immune condition, and the severity of the illness.  Children, particularly those under the age of five, are more likely to develop serious disease due to their smaller airways, underdeveloped immune systems, and sensitivity to viral infections. Elderly people (particularly those over the age of 65 are more likely to experience serious complications due to weakening immune systems, the prevalence of chronic medical disorders (such as heart disease or diabetes), and reduced lung function. We attempted to describe the post-invasion repercussions of HMPV in youngsters and the elderly in the table below.²⁰

 

 

 Table 2: Summary of post-Invasion Consequences of HMPV in Children: ^{21, 22, 23, 24, 25, 26}

 

Table 3: Summary of post-Invasion Consequences of HMPV in the Elderly: ^{27, 28,29,30,31}

Consequence	Description	Impact on the Elderly
Pneumonia	A severe and common consequence of HMPV is lung tissue inflammation, which can escalate to respiratory failure.	A higher risk of pneumonia, which may necessitate hospitalization or ventilator assistance in severe cases. Pneumonia is the primary cause of death in older people with HMPV.
Chronic Respiratory Impairment	Prolonged respiratory issues, such as difficulty breathing and decreased lung function, can last long after the acute phase of infection.	Elderly people may develop chronic obstructive pulmonary disease (COPD)-like symptoms following infection, which can lead to long-term respiratory problems.
Exacerbation of Pre-existing Conditions	HMPV can worsen pre-existing diseases such heart failure, COPD, and asthma.	Individuals with pre-existing lung or heart diseases are more likely to experience consequences such as heart failure, worsening COPD, or severe wheezing.
Hospitalization and ICU Admission	The severity of HMPV infection increases the likelihood that elderly individuals may require hospitalization, including ICU care.	The elderly have higher rates of hospitalization and may need intensive care, especially if the infection leads to respiratory failure.
Acute Respiratory Distress Syndrome (ARDS)	Severe lung inflammation causes widespread damage, hypoxia, and the requirement for ventilator assistance.	Elderly people are more likely to develop acute respiratory distress syndrome (ARDS), which can be fatal and necessitate mechanical ventilation.
Secondary Bacterial Infections	HMPV can make older people more susceptible to secondary bacterial infections including bacterial pneumonia and sepsis.	The elderly are more likely to develop secondary infections following a viral infection, which can exacerbate the clinical course and raise the chance of death.
Cognitive Decline or Delirium	Severe infection, hospitalization, and respiratory distress can all lead to delirium or cognitive deterioration in elderly people.	Elderly individuals with severe infections may experience delirium, cognitive impairment, or worsening of pre-existing dementia symptoms during or after treatment.
Prolonged Recovery	Recovery from HMPV infection might be sluggish in older persons, resulting in prolonged weakness, weariness, and lower activity levels.	Prolonged recovery from sickness can reduce quality of life, and older persons may require additional care, rehabilitation, or physical therapy.

 

 

Post-Invasion Consequences of HMPV in Immunocompromised Persons: 

Immunocompromised people—those with weaker immune systems as a result of HIV/AIDS, cancer treatments, organ transplants, or autoimmune diseases—are at a considerably increased risk of severe consequences and lengthy recovery from infections such as Human Metapneumovirus (HMPV).³² In these cases, HMPV can cause more severe sickness, longer recovery durations, and a greater risk of subsequent infections. Immunocompromised people may be unable to eliminate the infection as effectively as those with normal immune function. This can result in prolonged viral replication and shedding, raising the risk of transmission and causing symptoms to last longer. Pneumonia is a typical side effect of HMPV infection, and in immunocompromised people, it can be significantly more severe. This causes respiratory discomfort and hypoxia (low oxygen levels in the blood). ARDS is another significant consequence in which widespread lung inflammation causes severe difficulty breathing and may necessitate mechanical support.³³ These conditions are associated with a high death risk in immunocompromised patients. The immune system's inability to adequately handle HMPV infection can lead to subsequent bacterial infections such bacterial pneumonia or sepsis. These infections complicate therapy, necessitating antibiotics or other measures, and can lengthen hospital stays and recovery times. Immunocompromised people may struggle to establish an effective immune response against HMPV. ³⁴ This could lead to a prolonged illness and lengthier healing times, with symptoms such as chronic cough, wheezing, and exhaustion lasting weeks or months. Many immunocompromised patients have pre-existing illnesses like COPD, asthma, or interstitial lung disease. An HMPV infection can aggravate these problems, resulting in worsening symptoms, frequent hospitalizations, and more serious outcomes. In severe circumstances, HMPV can cause multi-organ dysfunction due to systemic inflammation. This is especially concerning for immunocompromised people, who may already have additional organ vulnerabilities such as liver, renal, or cardiac disorders. Infected people may develop sepsis, a life-threatening systemic inflammatory response that raises the risk of organ failure and death. Long-term sickness, frequent hospitalizations, and respiratory distress can all cause anxiety, depression, and even cognitive deterioration in immune-compromised people, especially the elderly and fragile. Recovery from such a severe sickness frequently necessitates mental health care.³⁵

 

 

Table 4: Summary of post-Invasion Consequences of HMPV in Immunocompromised Persons ^{36, 37, 38}

Consequence	Description	Impact on Immunocompromised Persons
Prolonged Viral Shedding	Immunocompromised persons may suffer prolonged viral shedding, which means the virus stays in the body for a longer period of time.	Increased transmission risk: Because these patients are contagious for longer periods of time, the virus has a higher chance of spreading to others. Prolonged healing time.
Severe Pneumonia	HMPV can induce severe viral pneumonia, resulting in lung inflammation, difficulties breathing, and hypoxia.	Increased risk of pneumonia: Immunocompromised people are more likely to develop severe pneumonia, which may necessitate mechanical ventilation or even cause respiratory failure.
Acute Respiratory Distress Syndrome (ARDS)	A life-threatening illness characterized by extensive pulmonary inflammation, which leads to severe hypoxia and respiratory failure.	ARDS might develop more quickly, necessitating intense care, ventilator support, and a lengthy recovery. It has a significant mortality rate among immunocompromised patients.
Secondary Bacterial Infections	Viral infections, such as HMPV, can increase the risk of subsequent bacterial infections.	Increased risk of bacterial co-infections: Immunocompromised individuals are more likely to get secondary bacterial infections, which can exacerbate the condition and necessitate extra therapies.
Prolonged Inflammation	Persistent immunological response causes protracted inflammation in the respiratory tract.	Prolonged respiratory symptoms: Chronic inflammation can cause a persistent cough, wheezing, and exhaustion for weeks or even months, hindering rehabilitation.
Exacerbation of Underlying Conditions	HMPV can worsen pre-existing chronic respiratory disorders such COPD, asthma, and interstitial lung disease.	Individuals with underlying lung diseases are more likely to have worsening symptoms, more hospitalizations, and longer recovery times.
Impaired Immune Response to Infection	Immunocompromised people cannot mount an effective fight against the infection.	Delayed or incomplete viral clearance: Because of a weakened immune system, HMPV may remain in the body for longer periods of time, resulting in prolonged illness, complications, and an increased risk of chronic symptoms.
Organ Dysfunction (Multi-organ)	Severe viral infections can cause systemic inflammation and damage to various organs, including the liver, kidneys, and heart.	Multi-organ failure: Immunocompromised people, particularly those with underlying medical conditions, are more likely to develop multi-organ dysfunction, which can lead to sepsis or death.
Delayed Recovery	Due to decreased immunity, recovery from infection may be much slower than in immunocompetent persons.	Prolonged illness: Immunocompromised patients may experience months of weariness, weakness, and respiratory problems following the acute phase, necessitating extensive rehabilitation.
Cognitive and Psychological Effects	The stress of extended sickness, hospitalizations, and physical disability can all lead to mental health problems.	Psychological stress: Prolonged illness and recovery, combined with the physical toll of the infection, can cause depression, anxiety, and cognitive loss, particularly in elderly immunocompromised people.
Increased Mortality Risk	Because of the intensity and duration of the illness in immunocompromised people, the risk of death is increased.	Increased mortality risk: Complications such as pneumonia, ARDS, sepsis, and other organ failures dramatically raise the chance of death in highly immunocompromised people.

 

 

Diagnosis of HMPV Virus: 

Human Metapneumovirus (HMPV) infection is diagnosed primarily through clinical signs, patient history, and laboratory tests.   Healthcare practitioners will begin by reviewing the patient's medical history, with an emphasis on respiratory symptoms such as cough, fever, nasal congestion, and sore throat. Shortness of breath, wheezing, fatigue. Gastrointestinal problems such as diarrhea or vomiting (particularly common in youngsters). Polymerase Chain Reaction (PCR) testing is regarded as the most sensitive and specific approach for identifying HMPV.³⁹ It entails amplifying viral RNA from respiratory specimens (such as throat swabs, nasopharyngeal swabs, and sputum samples). PCR can accurately detect HMPV, even in instances with moderate or unusual symptoms. It distinguishes HMPV from other respiratory viruses. Although HMPV can be cultured from respiratory specimens in specialized labs, this approach is rarely utilized in general practice because to its complexity and longer turnaround time when compared to PCR. Direct Fluorescent Antibody (DFA) Testing detects HMPV antigens in respiratory samples. It yields faster findings than PCR, but it is less sensitive and may produce false negatives if the virus load is low.⁴⁰ The Enzyme-Linked Immunosorbent Assay (ELISA) can identify viruses (antigens) or the body's immunological reaction (antibodies). It is more widely employed in research settings than in the regular diagnosis of acute infections. ELISA can be utilized for epidemiological studies or retrospective diagnosis, however it is not commonly used for acute HMPV infection.⁴¹ Reverse transcription-polymerase chain reaction (RT-PCR) may detect HMPV-specific RNA sequences in respiratory tract samples and is widely employed for early detection, particularly during outbreaks. These imaging studies can help rule out alternative causes of respiratory distress and determine the severity of lung involvement. In severe cases of HMPV infection, the X-ray may reveal symptoms of lower respiratory tract involvement, such as lung infiltrates, but these are nonspecific. Because the symptoms of HMPV might be similar to those of other respiratory diseases (such as influenza, RSV, adenovirus, and corona virus), diagnostic testing is essential for distinction.⁴² Laboratory tests can identify the precise pathogen causing the disease, allowing for more targeted therapy and isolation precautions. In some circumstances, particularly in young children or immunocompromised persons, patients may be infected with several respiratory pathogens. Molecular multiplex testing permits the detection of numerous viruses (including HMPV) from a single sample, which helps identify co-infections.⁴³

 

 

Table 5: Summary of Diagnostic Methods for HMPV Virus: ^{41, 42, 43}

Method	Description	Advantages	Limitations
PCR	It detects viral RNA in respiratory samples.	Highly sensitive, specific, and rapid	Requires sophisticated lab equipment
Viral Culture	Cultures live virus from respiratory samples	Confirms live virus, helpful for research	Slow, requires specialized facilities
DFA	Detects viral antigens	Rapid results	Less sensitive than PCR; false negatives may occur.
ELISA	Detects antibodies or viral antigens	Can be utilized for research and retrospective diagnosis.	Less commonly used for acute diagnosis
Chest X-ray	Imaging to assess complications	Can detect complications like pneumonia	Nonspecific, does not diagnose HMPV

 

 

Preventative measures: ^{44, 45, 46}

Human Metapneumovirus (HMPV) infection prevention strategies are similar to those used to treat other respiratory viruses such as influenza and the common cold. Because there is no specific vaccine or antiviral treatment for HMPV, the primary goal is to reduce transmission and infection risk. Wash your hands frequently with soap and water for at least 20 seconds, particularly after coughing, sneezing, or touching possibly contaminated surfaces. Use a hand sanitizer with at least 60% alcohol. Avoid contacting your eyes, nose, or mouth with unwashed hands, as these are typical entrance routes for viruses. To avoid spreading respiratory droplets, always cover your mouth and nose with a tissue or your elbow when coughing or sneezing. After using tissues, discard them immediately and wash your hands. If possible, avoid those who have respiratory symptoms such as coughing, sneezing, or fever. If you have symptoms of a respiratory infection (fever, cough, shortness of breath), stay at home to limit the risk of spreading the virus. Limit your time in crowded, enclosed areas, particularly during high respiratory illness seasons. To limit the risk of virus transmission, regularly sanitize surfaces such as doorknobs, light switches, phones, keyboards, and other frequent areas. Wearing a mask can help minimize the spread of respiratory droplets in areas with inadequate ventilation or where you are likely to come into contact with sick people (e.g., healthcare settings, public transportation). Maintain a nutritious diet, exercise regularly, get adequate sleep, and manage stress to boost your immune system and lower your chances of contracting a serious illness if infected. Although the flu vaccine does not protect against HMPV, it can minimize the burden of other respiratory infections, lowering the overall risk of co-infection and consequences. Infants, young children, the elderly, and people with compromised immune systems are more likely to experience serious problems from HMPV infection. Additional care should be taken to reduce their exposure to potential sources of infection. Smoking and secondhand smoke can weaken the respiratory system, making people more susceptible to respiratory diseases like HMPV. Stay up to date on health-related guidelines, such as those from the Centers for Disease Control (CDC) or World Health Organization (WHO), especially during flu season or respiratory ailment epidemics. If someone in your household or community has been infected with HMPV, keep them away from others, particularly vulnerable people, until they recover. If someone else is infected, make sure they rest, stay hydrated, and get medical attention if necessary, especially if their respiratory symptoms worsen. 

Treatment options for HMPV Virus ⁴⁷ 

Human Metapneumovirus (HMPV) infection usually results in symptoms similar to those of other respiratory infections, such as the common cold, bronchiolitis, or pneumonia. There are currently no licensed antiviral medications for HMPV, thus treatment is mainly supportive. Several therapeutic techniques and interventions, however, may benefit in symptom management and prevention of repercussions, particularly in vulnerable populations. The table below highlights the available therapeutic options, their mechanisms of action, and their potential significance in HMPV infection control.

 

 

Table 6:  Non-Specific and specific treatment options for HMPV Virus with their mechanism of action: ^{48, 49, 50}

Treatment Option	Mechanism of Action	Role in Treatment
Supportive Care (Primary Treatment)	Symptom therapy includes water, fever control (acetaminophen, ibuprofen), and cough alleviation. No direct antiviral impact.	Relieves symptoms by providing comfort and reducing the severity of fever, cough, and respiratory distress. Typically used for mild to moderate instances.
Oxygen Therapy	Supplemental oxygen: Increases blood oxygen saturation when the patient is hypoxic (poor on oxygen). There is no direct antiviral effect.	Prevents hypoxemia: Used during severe respiratory distress or when oxygen saturation falls below safe levels (e.g., <92%).
Bronchodilators (e.g., Albuterol)	Beta-2 agonists stimulate beta-2 adrenergic receptors in smooth muscle of the airways, resulting in bronchodilation.	Reduces wheezing and respiratory distress: Can be used in people who have severe wheezing, particularly youngsters or those with asthma.
Corticosteroids (e.g., Prednisone)	Anti-inflammatory action: Inhibits pro-inflammatory cytokines, reducing the immune system's inflammatory response. Can help minimize airway edema.	Used in extreme cases: In hospitalized patients with considerable inflammation or those at risk of developing pneumonia or bronchitis.
Ribavirin (Off-label use)	The nucleoside analog inhibits RNA-dependent RNA polymerase, preventing viral RNA replication. However, its efficacy against HMPV is not well documented.	Potential antiviral treatment: Used in severe or high-risk situations, such as immunocompromised patients, although not always indicated for HMPV.
Palivizumab (Monoclonal antibody, Off-label)	Neutralizes RSV and other respiratory viruses. Targets the virus's F (fusion) protein, preventing it from entering host cells. (Most commonly used for RSV).	Preventative: Primarily used for RSV, however studies on its efficacy against HMPV are continuing. Could be explored for high-risk groups.
Antipyretics (e.g., Acetaminophen, Ibuprofen etc.)	Reduces fever: Acetaminophen reduces prostaglandin synthesis in the brain, whereas ibuprofen inhibits cyclooxygenase (COX), hence decreasing inflammation and fever.	Fever control: Reduces fever and relieves symptoms.
Hydration and Fluids	Maintains fluid balance: Ensures proper hydration to avoid dehydration, which can exacerbate symptoms such as weariness and coughing. No direct antiviral impact.	Maintains fluid balance: Proper hydration prevents dehydration, which can increase symptoms like fatigue and coughing. There is no direct antiviral impact.
Mechanical Ventilation (In Severe Cases)	Positive pressure: Supports breathing by supplying air or oxygen directly into the lungs via a ventilator tube. No antiviral impact.	Life-saving in severe cases: Required for individuals with respiratory failure who cannot maintain adequate oxygen levels.
Antibiotics (If Secondary Bacterial Infection Occurs)	Antibiotics are used to treat bacterial pathogens that can cause secondary illnesses, such as pneumonia. HMPV has no antiviral impact on itself.	Treats secondary infections: Used only when there is a confirmed or suspected bacterial co-infection (e.g., bacterial pneumonia).

 

 

 

Indian Government advisory about HMPV Virus: ^{51, 52} 

The Indian government has issued advice in response to recent HMPV instances recorded in the country. As of January 8, 2025, seven instances had been confirmed, with the majority affecting newborns and young children. According to Newsweek, one of the HMPV-infected kids was a three-month-old girl who was taken to Baptist Hospital in Bengaluru. According to The Hindu, a two-month-old boy in Ahmedabad, western India, contracted the HMPV virus. The ministry continued: "HMPV is already in circulation globally, including in India, and cases of respiratory illnesses associated with HMPV have been reported in various countries." The Union Health Ministry has instructed states to improve respiratory illness surveillance and increase public awareness of HMPV prevention measures. States such as Uttarakhand have issued cautions to prevent the spread of respiratory infections caused by seasonal influenza and HMPV. Health officials emphasize that, while caution is required, there is no need for concern. The Govt. has declared that HMPV is not a lethal virus and asked the public to be calm. Children under the age of three and those who are immunocompromised should exercise extreme caution.

Conclusion and future strategies to fight against HMPV Virus:

Human Metapneumovirus (HMPV) is not a novel disease; it has been identified as a major cause of respiratory illness since its discovery in 2001. While it normally produces mild cold-like symptoms, it can cause serious respiratory distress in sensitive populations such as small children, the elderly, and immunocompromised people. The current increase in HMPV cases highlights the importance of attention, especially given the increased global awareness about respiratory viruses following COVID-19. HMPV, on the other hand, is less contagious and less severe than Severe Acute Respiratory Syndrome Corona virus 2 (SARS-CoV-2) , and the vast majority of cases resolve without sequelae. Public health interventions like as enhanced hygiene, respiratory etiquette, and surveillance systems have proven beneficial in limiting its spread. Research into HMPV vaccines is ongoing. Advances in mRNA and other vaccination technologies may speed up the development of preventive interventions. A vaccination would be especially beneficial for high-risk populations. Enhanced diagnostic technologies can aid in the early detection and distinction of HMPV from other respiratory viruses such as influenza and RSV, allowing for timely and focused therapies. Strengthened global surveillance systems can provide early warnings of epidemics, particularly in areas with high HMPV prevalence. Data sharing between countries can help us better understand the virus's behavior. Governments are likely to include HMPV into normal public health monitoring and response plans, assuring readiness for potential future surges. Continuous respiratory health education programs, with a focus on basic preventative measures, will be crucial in reducing HMPV transmission. HMPV currently lacks specific antiviral therapies, therefore management is mostly supportive. Research into effective treatments is a major priority. Environmental and socioeconomic factors, such as population density and access to healthcare, may have an impact on the virus's spread throughout countries. With the correct investments in public health infrastructure, research, and global collaboration, HMPV outbreaks can be effectively managed, reducing their impact on health systems and communities. While the virus is unlikely to cause a pandemic, it will continue to be monitored and managed as part of global health initiatives.

 

 

List of abbreviations Used:

CDC: Centers for Disease Control COPD: Chronic obstructive pulmonary disease COX: Cyclooxygenase DFA: Direct Fluorescent Antibody ELISA: Enzyme-Linked Immunosorbent Assay HMPV: Human metapneumovirus IMA: Indian Medical Association

OTC: Over-the- counter      PCR: Polymerase Chain Reaction RNA: Ribo nucleic acid RSV: Respiratory Syncytial Virus RT-PCR: Reverse transcription polymerase chain reaction (SARS-CoV-2): Severe Acute Respiratory Syndrome Corona virus 2WHO: World Health Organization

 

 

Conflict of interest: The authors declare no conflict of interest.

Acknowledgement: We are thankful to the Principal, Columbia Institute of Pharmacy, Raipur (C.G.), Principal, Pt J.N.M. Medical College, Jail Rd, opp. Central Jail, Moudhapara, Raipur-492001, Chhattisgarh, India and Dean, College of Veterinary Science and Animal Husbandry, Anjora, Durg-491001, Chhattisgarh, India  for providing necessary facilities to complete this review article.

Funding: We do not receive any kind of funding from any source for this review article.

Author’s contribution: Dr. Trilochan Satapathy: Conception and Preparation of content

Abhisek Satapathy: Editing the content

Abinash Satapathy and Neha Yadav: Grammar and English language correction

Manisha Chandrakar, Kunal Chandrakar: Review the content

Ethical Approval: Not applicable

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