Given an unusual uptick in the cases of “seasonal influenza” in the recent days, the health ministry Friday said that it was keeping a close watch on the situation in various states/UTs through the Integrated Disease Surveillance Programme (IDSP) network on real-time basis.

The Ministry is also tracking and keeping a close watch on morbidity and mortality due to the H3N2 subtype of the seasonal Influenza. Young children and old-age persons with co-morbidities are the most vulnerable groups in context of seasonal influenza. So far, Karnataka and Haryana have confirmed one death each from H3N2 influenza.

Seasonal influenza is an acute respiratory infection caused by influenza viruses which circulate in all parts of the world, and the cases are seen to increase during certain months globally. India every year witnesses two peaks of seasonal influenza: one from January to March and other after monsoon season. The cases arising from seasonal influenza are expected to decline from March end. State surveillance officers are therefore fully geared to meet this public health challenge.

Real-time surveillance through countrywide network of labs

A near real-time surveillance of cases of Influenza like Illness (ILI) and Severe Acute Respiratory Infections (SARI) presenting in OPDs and IPDs of health facilities is undertaken by Integrated Disease Surveillance Programme (IDSP), National Centre for Disease Control (NCDC).

According to the latest data available on IDSP-IHIP (integrated health Information Platform), a total of 3038 laboratory confirmed cases of various subtypes of Influenza including H3N2 have been reported till March 9 by the states. This includes 1,245 cases in January, 1,307 in February and 486 cases in March (till March 9).

Further, the IDSP-IHIP data from health facilities indicate that during the month of January 2023, a total of 397,814 cases of Acute Respiratory Illness/Influenza Like Illness (ARI/ILI) were reported from the country that increased slightly to 436,523 during February, 2023. In the first nine days of March 2023, this number stands at 133,412 cases.

The corresponding data for admitted cases of severe acute respiratory illness (SARI) is 7,041 cases in January 2023, 6,919 during February 2023 and 1,866 during the first nine days of March 2023.

In 2023 (till February 2), a total of 955 H1N1 cases have been reported. Majority of the H1N1 cases are reported from Tamil Nadu (545), Maharashtra (170), Gujarat (74), Kerala (42) and Punjab (28).

In India, an integrated surveillance of Influenza like Illness (ILI) and Severe Acute Respiratory Illness (SARI) for the detection of human influenza virus and SARS-COV-2 virus is ongoing through structured ILI/SARI surveillance network of 28 sites. The surveillance network is comprised of 27 DHR-ICMR’s Virus Research & Diagnostic Laboratories and country’s National Influenza Centre (WHO-NIC) housed at ICMR-National Institute of Virology Pune, also a WHO Collaborating Centre for Global Influenza Surveillance & Response System (GISRS).

During the period of first nine weeks (January 2 to March 5) of 2023, the surveillance network has monitored the human influenza virus and SARS-CoV-2 infection in SARI and ILI cases. The influenza typing results are summarized below:

It can be seen that Influenza H3N2 is the predominant sub-type among the samples testing positive for influenza, since the beginning of this year.

Public Health Measures

Guidelines on seasonal Influenza: The ministry has provided guidelines on categorization of patients, treatment protocol, and guidelines on Ventilatory management to the States/UTs which are also available on the website of the ministry (www.mohfw.nic.in) and NCDC (ncdc.gov.in). MOHFW has also advised the State Governments for vaccination of health care workers dealing with H1N1 cases.

ICMR has also issued an advisory regarding this.

Drugs and Logistics

Oseltamivir is the drug recommended by WHO. The drug is made available through the Public Health System free of cost. Government has allowed sale of Oseltamivir under Schedule H1 of Drug and Cosmetic Act in February 2017 for wider accessibility and availability. Adequate logistics is available with the States. However, in case of any emergencies the Govt. of India has been providing the support to the States to tide over the crisis.

Additionally, NITI Aayog will hold an inter-ministerial meeting tomorrow, i.e., 11th March 2023 to review the Seasonal Influenza situation in the states and for ways to further support them in terms of public health measures, management guidelines and protocols to manage the increasing Seasonal Influenza cases.