Public health alert as flu cases rise in Kerala

Influenza cases are on the rise across the state and the co-circulation of different flu viruses poses a threat to vulnerable categories, especially pregnant women and the elderly, health officials have warned.

Viruses such as influenza B and A (H3N2 and H1N1), respiratory syncytial virus (RSV), and COVID-19 co-circulate in the community. Distinguishing them based on clinical symptoms alone is impossible, as the symptoms often overlap.

The Ministry of Health has advised people to observe respiratory hygiene and etiquette and use masks in public places as these viruses are highly contagious.

“Until April this year, we only had isolated cases of influenza. However, cases now appear to be on the rise, with 941 cases and nine deaths reported so far. Of these, 457 cases and five deaths were reported in the month of May. Early treatment with antivirals such as Oseltamivir can save lives and people – especially the elderly, pregnant women and those who need to be cautious.

In 2025, the state also reported 7,193 flu cases and 43 deaths.

An evolving virus

Influenza A is a particular threat and has the potential to cause pandemics due to the virus’s ability to constantly evolve (antigenic drift and shift), which allows it to evade the human immune system. This means that the flu virus can either constantly re-infect people, requiring yearly updated vaccines, or it can suddenly emerge as an entirely new subtype to which people may have no immunity at all. Therefore, thorough surveillance to understand seasonal patterns and timely vaccination with updated vaccines are important to protect vulnerable groups.

Influenza A virus can lead to a lower respiratory tract infection and trigger a cytokine storm (overreaction of the immune system), leading to lung inflammation and fluid accumulation, which could be exacerbated by a secondary bacterial infection.

“Elderly people, especially people over 70, are disproportionately vulnerable to the flu virus and complications. Flu vaccines are available in the private sector and on the open market. We would recommend that all seniors get a flu shot every year,” said a health official.

The state currently follows integrated guidelines for the treatment of patients with influenza-like illness (ILI)/COVID-19 symptoms. These guidelines state that individuals with symptoms of COVID or influenza will be tested and treated, especially if individuals belong to a high-risk vulnerable category (persons with comorbidities, serious chronic diseases, the elderly, or pregnant women).

Treatment of patients with influenza, regardless of virus variants, is based on warning signs such as decreased oxygen saturation, shortness of breath, decreased blood pressure, etc. An individual’s risk of developing severe disease or complications will vary depending on their comorbidities.

Health officials fear hospitals could be overwhelmed as flu and other infectious diseases such as dengue fever surge in the coming weeks, complicating doctors’ ability to distinguish and treat patients with fever and respiratory illness in outpatient clinics.

Given the enormous burden of chronic multimorbidity in its senior population, influenza is sure to keep healthcare professionals on their toes this season. The Ministry of Health emphasized that the emphasis is on prevention and early testing and treatment of patients with symptoms.

Emphasis is placed on non-pharmacological interventions to prevent respiratory disease – masking, avoiding crowded places and cough hygiene in public places

Published – 30 May 2026 19:56 IST