While people were slowly going ‘off-masks’, thinking Covid is almost over, they are now witnessing a new virus in the block – Influenza A-H3N2 – whose symptoms seem somewhat similar to corona virus. According to the World Health Organization (WHO), A-H3N2 is a subtype of influenza A viruses, that circulate and cause seasonal epidemics.
Dr Sushila Kataria, Senior Director, Internal Medicine, Medanta, Gurugram says, "The symptoms for A-H3N2 include headache, fever, muscle pain, cough, sneezing, cold, body chills and fatigue. In the last one month, there has been an increase in the number of flu cases. This is usually the case in spring season. This time, the cases are the same, but the fever severity is a bit more and the cough is more intense. The cough is severe because of swelling on vocal cords and laryngitis (an inflammation of the voice box from overuse, irritation or infection).”
Further, the WHO says that the effects of seasonal influenza epidemics in developing countries are not fully known, but research estimates that 99 per cent of deaths in children under five years of age with influenza-related lower respiratory tract infections are found in developing countries. All age groups can be affected due to this virus, but pregnant women, children under 59 months of age, elderly, and people with chronic diseases are likely to get more infected due to this virus.
“There definitely has been an increase in cases. All age groups are getting influenza, including children. It is mostly mild, but in those with co-morbidities, and, in the elderly, it is slightly more severe, and, at times, requires hospitalisation,” Dr Kataria added.
Echoing the same view as Dr Kataria, Dr Manoj Goel, Director, Pulmonology, Fortis Memorial Research Institute (FMRI), states that influenza is a common flu which occurs almost every year.
“It has been there for eight years now. This time, it is more virulent, causing more cases. In the last two years, we didn’t see much of influenza because of Covid, which does not provide any immunity to this virus. This month, we have witnessed around 30-40 per cent such patients. Currently, oseltamivir drug is given to treat those who are at high risk, or have severe disease.”
It is not easy to compare A-H3N2 virus with corona virus because Covid came as a pandemic, but A-H3N2 is an endemic virus which persists, and can come back in future also.
Dr Goel suggests that both corona virus and Influenza A-H3N2 are flu-like illnesses, which would cause cough, fever, sore throat. These are viral diseases which affect respiratory tract in a similar way, and the severity can vary from time to time. However, the former is much more infectious than the latter, as it causes severe pneumonia.
“A-H2N3 has circulated before, and, therefore, there is some immunity against it, unlike Covid, which was totally new and against which there was no immunity. To prevent the disease, one can take an influenza shot,” suggests Dr Kataria.
Dr Manoj Kumar, a clinical biochemist from Narendra Mohan Hospital, Ghaziabad, laments that influenza A-H3N2 virus might witness more increase in cases because of under-reporting.
“Some of the states where cases are usually under-reported are Uttar Pradesh (UP), Madhya Pradesh (MP), Rajasthan, Haryana and Gujarat. The government must direct screening at bus terminals, railway stations, airports and other places to prevent an increase in the number of cases. With the festival season round the corner, we need to be more vigilant about testing and treating patients. Don’t forget to mask up, sanitise and wash hands properly. Avoid crowded spaces as much as possible,” he advises.
At Apollo Hospital in Ahmedabad, doctors are doing RTPCR flu panel (Flu A, Flu B, H1N1 and H3N2) test approved by the Government of Gujarat, informs microbiologist Pankti Shah.
“The disease has the ability to create a local outbreak. We witnessed three cases in December last year. This year, we witnessed 11 cases each in January as well as in February. This month, there haven’t been any cases yet,” informs Shah.
As per Dr Kataria, influenza virus is nothing exceptional as far as India is concerned. She explains, “This time of the year, you see the increase in cases and this tapers off as summer comes in April.”