Human Metapneumovirus (HMPV): Understanding the infection and its impact on cancer patients

Human Metapneumovirus (HMPV): Understanding the infection and its impact on cancer patients

Dr. P. Vijay Anand Reddy, MD, DNB

Director, Apollo Cancer Centre

Apollo Hospitals, Hyderabad

For correspondence: [email protected]

The incidence of Human Meta Pneumovirus (HMPV) has been increasing in recent times across the world and in India as well. With so many varying narratives being propagated across media, it is imperative to know about the infection as well as its impact on cancer care.

HMPV is a type of common respiratory virus belonging to a family of viruses called pneumoviridae. It was discovered by Dutch Scientists in 2001, but research shows that it has been a source of respiratory infections for more than 50 years.

HMPV is a seasonal virus with increasing incidence in winter and early spring. It can affect any age population, but people at high risk are newborns, children under 5, people older than 65, people with asthma who use steroids, people with chronic obstructive pulmonary disease, people with weakened immune systems due to conditions like cancer or HIV or who have had an organ transplant.

HMPV is a contagious virus that spreads from person to person through close contact. A person is expected to be exposed to the virus when they touch the surfaces that contain the virus and immediately touch their mouth, nose or eyes or when they come in contact with droplets from an infected person through sneezing, spitting or coughing. Diagnosis is done through a swab test followed by PCR testing.

After the virus enters the body, the incubation period is 3-6 days before symptoms appear. Symptoms include cough, nasal congestion, runny nose, fever, Sore throat, nausea, vomiting, and diarrhoea. This is a self-limiting infection that will subside in 2 -5 days. Management mainly includes adequate hydration; however, in patients with comorbidities and compromised immunity, the infection can be long-lasting and can cause severe respiratory distress, resulting in the need for oxygen requirement and injectable steroids. There is no antiviral therapy or vaccine available. There is limited data on the usage of Ribavarin as an antiviral therapy and intravenous Immunoglobulin (IV Ig).

Amongst cancer patients who developed HMPV infection, historical data shows a 43% rate of lower respiratory tract infection. Incidence rates are higher in patients who are receiving high-dose chemotherapy and are undergoing stem cell transplants. Mortality rates in patients who developed HMPV are around 7-10%. These patients may often develop oxygen requirement and secondary infections, which may further result in severe morbidity and mortality. The focus in these patients will be on maintaining immunity, resolving neutropenias, if any, and infection control measures for nosocomial infections. However, it should be noted that HMPV-associated death is only 2%. Treatment includes Antiviral therapy in the form of Ribavarin and Immunoglobulin therapy.

In patients who are on active cancer treatment and developing HMPV, there are no established guidelines. However, general measures like delaying chemotherapy for up to 2 weeks after diagnosis will be helpful.

General preventive measures that can be employed are avoiding crowded places, usage of masks when going out, regular hand washing and maintaining adequate ventilation of indoor spaces. Overall, this is a mild infection that is seasonal and self-limiting, with limited mortality rates.