New Delhi: Amid concern over the rising number of H1N1 cases across the country, doctors said the rise and clustering of the virus isn’t unusual.
This comes as several parts of the country reported a sudden increase in the number of swine-flu patients.
Karnataka and Delhi have emerged as the worst-hit states, prompting local governments to issue health advisories and ramp up surveillance.
H1N1 cases in Karnataka crossed 4,000 this year, the highest in the country, with more than 2,000 reported from Bengaluru alone, according to surveillance data on the Integrated Health Information Platform (IHIP).
While Delhi reported 2,446 cases as of Thursday last week.
Dr. Swapnil Khadke, HOD, Critical Care Medicine, Fortis Hiranandani Hospital, Vashi, Navi Mumbai explained that multiple factors could be behind the spike and why some regions are reporting higher cases.
“The clustering of H1N1 cases in certain regions is usually because of a combination of factors rather than one single reason. Changes in weather, especially shifts in temperature and humidity, can influence how respiratory viruses spread and how long they remain active in the environment,” Dr Khadke said.
“People also tend to spend more time indoors during certain seasons, which increases close contact and transmission. Another important factor is immunity. Since influenza strains keep changing, the protection people have from previous infections or vaccinations may not always be enough. Local population movement, testing patterns, and awareness levels can also make some areas appear to have a higher number of cases,” he added.
Dr. Ashwini Collaco, Consultant, Pulmonology, Manipal Hospital, Goa agrees adding that “The spike in cases alone isn’t evidence of a new or unusually virulent virus.”
Earlier this week, Indian Council of Medical Research (ICMR) issued a statement clarifying that no new strain of Influenza A (H1N1) has been identified in the country and said there is no cause for panic over the seasonal influenza virus currently in circulation.
While most infections remain mild and there isn’t a threat of a nationwide surge, doctors said vigilance is key to protect vulnerable and high-risk individuals including older adults, pregnant women and those with chronic conditions.
Dr. Rommel Tickoo, Senior Director, Internal Medicine, Max Super Speciality Hospital, Saket said, “Most H1N1 infections continue to be mild to moderate, but severe disease can occur, particularly in older adults, pregnant women, young children and people with chronic heart, lung, kidney or metabolic disease.
“We are seeing some patients develop viral or secondary bacterial pneumonia and respiratory compromise requiring hospitalisation. At present, the key concern is the increased number of infections, which can translate into more severe cases among vulnerable populations.”
Doctors agreed that lingering symptoms such as cough and fatigue are common after recovery, but that certain warning signs should not be ignored.
“Post-viral cough, fatigue and reduced exercise tolerance can persist for several days to a few weeks after acute influenza and usually improve gradually. Persistent or worsening breathlessness, recurrent fever, chest pain, low oxygen levels or marked fatigue should prompt medical evaluation, particularly in high-risk individuals. Longer-term complications are uncommon after uncomplicated infection, but pneumonia, exacerbation of underlying lung disease or cardiac complications can occasionally prolong recovery,” Dr. Tickoo added.
