After a lull, H1N1 cases on the rise again in Karnataka

Over 400 cases reported this year, while 13 reported last year

H1N1 influenza is a subtype of Influenza ‘A’ virus, a communicable viral illness which causes upper and, in some cases, lower respiratory tract infection. File | Photo Credit: The Hindu photo library

Along with a host of viral and vector-borne ailments, Karnataka is also under the grip of H1N1 influenza.

Last year, when the second wave of COVID-19 had overwhelmed the State’s infrastructure, only 13 H1N1 cases were reported. However, this year cases have shot up to 409 in the first eight months itself.

According to data from the State Health and Family Welfare Department, a total of 458 H1N1 cases and three deaths were reported in 2020 when the pandemic began.

However, in 2021, cases reduced to 13 and doctors attributed the decline to increased surveillance and COVID-19 precautions such as use of masks and social distancing.

H1N1 influenza is a subtype of Influenza ‘A’ virus, a communicable viral illness which causes upper and, in some cases, lower respiratory tract infection. This results in symptoms such as nasal secretions, chills, fever, decreased appetite, and, in some cases, lower respiratory tract disease.

According to data, this year so far 1,621 samples have been tested (from January till August 19) of which 409 have tested positive. Last year, although 2,032 samples were tested, only 13 had tested positive.

Over 50% of this year’s total H1N1 cases have been recorded in the last two months. Udupi has reported the highest number with 200 cases as H1N1 testing was done only at Manipal Centre for Virus Research (MCVR) for the first few months.

“Although there are 12 designated laboratories for H1N1 testing across the State, in the first quarter of 2022 testing was being done only in MCVR,” sources said.

ILI/SARI testing

State Health Commissioner Randeep D. attributed the rise in cases to increased testing of primary contacts, especially in clusters and among ILI/SARI patients at hospitals.

“We have given standing instructions to hospitals to compulsorily test all ILI/SARI patients for H1N1, admit patients on time, and commence symptomatic treatment,” he said.

C. Nagaraja, director of the State-run Rajiv Gandhi Institute of Chest Diseases (RGICD), said the virus exhibits seasonality and there could be more cases during the winter and post monsoon months.

“We have been regularly testing ILI/SARI patients for H1N1 if they test negative for COVID-19 as both these diseases have similar manifestations. Last year, cases were low because people largely followed COVID-19 appropriate behaviour. Now, complacency has set in. It is advisable people wear masks and maintain hand hygiene at least in crowded areas,” he said.

Satyanarayana Mysore asserts need for Influenza vaccination

Satyanarayana Mysore, chairman of the Department of Pulmonology at Manipal Hospitals, asserted the need for Influenza vaccination.

“Senior citizens and those with co-morbidities should speak to their healthcare providers if they are eligible for vaccination. Those with pre-existing lung disease such as asthma, bronchitis, and smoking-related chronic obstructive pulmonary disease (COPD) are potential candidates for the Influenza vaccine,” he said.

He said that there should be a gap of at least 30 days between the COVID-19 and the Influenza vaccinations.