Delhi made influenza a notifiable disease after the 1918 pandemic killed 7,044 people in the city

A European traveller arriving in Delhi from Simla was among the first influenza cases noticed by the province’s chief medical officer in 1918. Within months, Delhi city recorded 7,044 deaths, while rural parts of Delhi Province recorded another 16,131 in October and November.

The outbreak had appeared relatively limited through September, with patients reporting fever, sore throat and cough. By October, it was more frequent and severe. Civil Hospital cases climbed from isolated admissions in the first week of the month to more than 100 daily by the third; 181 cases were recorded on October 14. Severe illness included pneumonia, bronchitis and pleurisy.

The scale of the epidemic led the Delhi Municipality’s sanitation sub-committee to consider notification rules in 1920. It reviewed practices in Bombay, Madras and England before recommending that ordinary influenza be included under the Punjab Municipal Act, then governing the city’s municipal administration. The September 1920 notification gave the municipality powers to act against its spread.

Today, H1N1 is a reportable infection under Delhi’s infection-control guidelines, though individual seasonal influenza cases are not all reportable. Delhi’s current H1N1 count has reached 2,729, with Lok Nayak Hospital setting aside isolation beds.