Subscribe
The strange similarity in the place and time of the rapid spread of human metapneumovirus (HMPV) — China and around Christmas — with the COVID-19 virus has scared people worldwide, including in India. But experts have pointed out that the latest virus has limited genetic sequences and little chance of mutating into virulent life-threatening strains as happened during the COVID-19 pandemic.
Recently, the World Health Organization (WHO) has confirmed that HMPV is a common respiratory virus found to circulate in many countries in winter through to spring; and also sought to clarify that the recently reported surge in China has not been “overwhelming”.
In Kolkata, West Bengal, a few people were diagnosed with the infection in November-December last year and recovered. News reports have pointed out that state laboratories reported some new cases during the same period, which led a general atmosphere of fear in the city.
Kolkata-based senior pulmonologists, however, reminded that the virus has been found almost a quarter century back; and have confirmed that they have been treating patients infected with the virus for atleast a decade. The Kolkata Municipal Corporation (KMC) has confirmed that they have received no guideline or directions so far from the state government.
“Though nothing can be categorically said till now; but based on the available information, it seems that the virus, an RNA one like SARS-COV-2 that caused COVID-19, has fewer genotypic sequences and, so far, reported fewer variants,” pointed out virologist Saumitra Das, chair, microbiology and cell biology department, Indian Institute of Science, Bangalore, and former director of the National Institute of Biomedical Genomics, Kalyani.
The virus, however, hasn't been sequenced too many times so far, the professor stressed. "We should tread carefully on the virus and continue to monitor it closely."
Even the mutations of HMPV that occured so much, they were mostly ‘silent’ in nature and played no role in changing its expression and virulence.
The virulence and severity of COVID-19 had root in its constant mutation and ability to regularly create newer variants, according to the experts. At least four major variants — omicron, delta, beta and alpha as well as several sub-variants have been identified.
According to scientists, HMPV can be divided into four subtypes: A1, A2, B1 and B2; while subtype A2 can be further divided into A2a and A2b.
“Unlike SARS-COV-2, HMPV is not expected to trigger severe cytokine storms and trigger fatality,” Chatterjee pointed out. A 'cytokine storm' or excessive release of cytokines, proteins that regulate immune response, is a pathological reaction in humans that can cause multi-organ failures for patients, as happened in several COVID-19 cases.
On January 7, WHO also allayed fears about the virus, stating that in many countries of the northern hemisphere, acute respiratory infections increase at this time of year, which are typically caused by seasonal epidemics of respiratory pathogens such as seasonal influenza, respiratory syncytial virus, and other common respiratory viruses, including HMPV.
Based on data published by China, covering the period up to December 29, 2024, WHO reported that acute respiratory infections (ARI) have increased during recent weeks but the observed increase in respiratory pathogen detections is within the range expected for this time of year; and the trend has not been overwhelming so far within the health care system, and no emergency declarations or responses triggered in China so far.
“We have been finding this virus within patients for at least a decade since when the BioFire test was conducted. BioFire ME panel tests for a comprehensive set of 14 bacteria, viruses and other microorganisms varieties, including the HMPV,” said Arup Haldar, a pulmonologist with the Calcutta Medical Research Institute in the city. “The virus mostly remains part of a viral mix; but sometimes can be found in isolation as well. Patients, infected with the virus, are found all through the year; but more in winter like other viral infections.”
The virus has been routinely found in the city, pointed out Ajoy Sarkar, a pulmonologist with the Peerless Hospital. There isn’t much reason behind the panic being created at a global level, the doctor said.
“We have found the virus in a patient even last November. Perhaps the recent memory of the impact of COVID-19 and the uncanny similarity with the time and place of occurrence, around Christmas and in China, has spiralled the concern; and got magnified as hardly any detailed information being made available by Chinese authority,” pointed out Sarkar.
Many people may already be immune to the virus as it was discovered 24 years ago in the Netherlands and is assumed to be in circulation globally for 60 years, experts noted. Moreover, the symptoms and impacts are like general cold viruses and not generally life threatening.
Like the normal cold and influenza viruses, HMPV, which enters the human system as droplets, can cause fever, cold and cough, sneezing, headache, throat infection and likewise. But the virus is mostly self-limiting.
“Generally, the incubation period is 5-9 days and the symptoms persist for about 4-5 days. However, it may create complications within infants, elderly and with those with chronic health problems and compromised immunity. In such cases, viral infections are being followed by bacterial infections. Medications are, generally, like those used to treat other cold and cough-triggering viruses; and should be taken as advised by the physicians,” pointed out the physicians.
According to state health department sources, five Kolkata laboratories have reportedly been found around 30 cases in November-December 2024; mostly in children and few in adults, but no unusual surge has been detected so far. Experts, however, reminded that the actual number may be much more; as the tests are only being advised when the patients face acute respiratory infections.
“KMC has not received any advisory or guidelines from the state health department so far on the virus,” confirmed physician Tapan Mukherjee, health advisor, KMC.
“Please keep in mind that there is no vaccine in place for the virus as of now,” noted Haldar.
“The test is costly; and there is no reason to do it in general, as the finding hardly changes the protocol of treatment, which is largely symptomatic,” stated Mukherjee.
Bengal chief minister Mamata Banerjee said people should be careful not to fall in the trap of a section of 'medical mafia' trying to milk money out of the latest concern.
