Delhi's 1918 influenza pandemic killed 7,044

An ailing European arriving from Shimla was among the first recorded influenza cases in Delhi in 1918. Within months, the disease claimed 7,044 lives in Delhi city, according to archival records accessed by PTI.

Two years later, in September 1920, the British India administration formally declared ordinary influenza an infectious disease in Delhi. This notification brought it under the Punjab Municipal Act, granting the Delhi Municipality powers to control its spread.

A 1918 medical report stated the first case noticed by the province's chief medical officer was a European who had recently arrived from Simla, where his family was also ill. A week later, another European in the same house was evidently infected.

Through September, the report said there was little cause for alarm, with patients suffering fever, sore throat, and cough. By October, cases became more frequent, severe, and fatal.

At Delhi's Civil Hospital, cases rose from ones and twos in the first week of October to over 100 a day by the third week. On October 14 alone, 181 influenza cases were recorded.

Severity and official response

Severe cases developed pneumonia, bronchitis, pleurisy, and empyema. Some patients suffered violent delirium, while others died suddenly from heart failure. Doctors across the province worked almost to a standstill.

An official 1918 communication recorded 23,175 influenza deaths across Delhi Province in October and November. Of these, 7,044 were in Delhi city and 16,131 in rural areas.

The scale of the epidemic prompted officials to consider bringing influenza under the city's infectious-disease law. A July 1920 file shows the Sanitation Sub-committee examining whether to include influenza or influenza pneumonia under the Punjab Municipal Act.

The committee reviewed arrangements in Bombay, Madras, and England, where different forms were already notifiable. Delhi officials recommended notification, arguing it would help detect cases, protect the public, and grant control powers.

"Although the difficulties of diagnosing ordinary Influenza are considerable," the committee said notification was "on the whole desirable." It noted there would be "no inconvenience to the general public and no considerable additional work to the medical practitioner."

The Delhi Municipality sought a draft notification for the Gazette. The Chief Commissioner issued the final notification in September 1920.

Modern reporting and distinctions

Dr. Sanchayan Roy of Apollo Spectra Hospital, Delhi, told PTI that H1N1 is covered under Delhi's infection-control guidelines as a reportable infection. However, not every seasonal influenza case is individually reportable.

Roy said this influenza virus was called the Bombay influenza virus. It couldn't be differentiated further. Possibly, it was H1N1, but could have been a mix of Influenza A and B also.

Dr. Arvind Aggarwal of Sri Balaji Action Medical Institute said patients developed acute fever, weakness, body pain, headache, sore eyes, cough, and bronchitis. Severe cases developed pneumonia within days.

The 1921 Census estimated 8.5 million deaths in India from the pandemic in 1918 and 1919. Historical research has put the figure at 12 million or more, Aggarwal said.

More than a century later, the reporting system makes sharper distinctions. "The reportable nature of swine flu or Influenza A disease is already included in the infection control guidelines formulated officially by the state of Delhi," Roy said.

He said suspected or confirmed reportable infections must be reported through public-health and hospital surveillance mechanisms. This does not mean all patients with seasonal flu must be individually reported.

"Influenza A includes H1N1 and H3N2, while Influenza B also circulates," Roy stated. H1N1 receives specific public-health attention. H3N2, Influenza B, and others are monitored through laboratory reporting and the Integrated Disease Surveillance Programme.

National Centre for Disease Control laboratory reporting formats contain Influenza A, pandemic H1N1, H3N2, Influenza B, and others among their tests. Roy said testing is not required for every patient. Those in mild Category A and many Category B patients may not be tested for H1N1 under national guidelines. Category C patients require testing, hospitalisation, and treatment.

"Public health reporting in this case will be done through clinical surveillance for suspected infection and laboratory testing where appropriate, as opposed to laboratory confirmation only," Roy concluded.