Swine flu has affected 69 people in the national capital but claimed no lives this year, the Delhi health department said on Wednesday.

However, Sir Ganga Ram Hospital (SGRH), a leading private hospital, has reported four swine flu-related deaths.

"No death due to swine flu has been reported in the capital… 69 confirmed cases of it have been reported," a senior Delhi health department official said.

But authorities at SGRH said four patients who had died at the hospital — three of them last month — were afflicted with the H1N1 virus.

About 15 cases of the disease have been reported at SGRH, and the first swine flu patient who died there was a 65-year- old woman from Gwalior. She had been admitted to the hospital late January and succumbed in early February, said Dr Atul Kakar, Senior Consultant, Department of Medicine, at the hospital.

The other three swine flu patients were all men and belonged to Delhi. A 35-year-old man died on April 17. The other two were aged 58 and 62.

"All these four patients were diagnosed with swine flu. There were multiple issues involved in their cases. Three of the patients did have some sort of co-morbid conditions, but the 35-year-old patient did not have a history of any serious ailments.

"So there is a possibility that the H1N1 virus was the cause behind his death," Kakar said.

"One swine flu patient was discharged today," he added.

Authorities at centre-run RML Hospital and Sadarjung Hospital said no death due to swine flu had been reported.

"We have just recorded five case of swine flu this year so far," a senior official at RML Hospital said.

"Out of three cases diagnosed at our hospital, only one is confirmed, the other two being suspected cases," said an official at Safdarjung Hospital.

Swine influenza, also called pig influenza or swine flu, is an infection caused by any one of several types of swine influenza viruses.

On March 31, Union Minister of State for Health Anupriya Patel had said in a written reply in the Lok Sabha that 160 people died from swine flu January 1 to March 26, while 6,062 cases were registered.

The highest number of deaths, 63, were reported from Maharashtra, while Telangana registered 16 deaths. Last year, between January to December 31, as many as 265 people had died, while 1,786 cases were reported.

Patel also said that stocks of the drug Oseltamivir, laboratory reagents and personal protective equipment have been kept with institutions under health ministry to support states and union territories reporting the seasonal influenza.

Dr Kakar of SGRH said people must be careful to keep the disease at bay.

"Physical contact must be kept at a bare minimum and patients must use a handkerchief while coughing or sneezing, as a precaution," he said.

"In case the disease hasn't been diagnosed timely, the alarming signs would be body temperature not settling, respiration rates going very high, confusion or disorientation or decrease in urine output and altering blood pressure," the doctor said.