As swine flu cases soar across the country with the start of the monsoon, health specialists are suggesting vaccines for those with chronic problems including heart diseases.

Praveer Agarwal, cardiologist in the Escorts Heart Institute here, stated, "A swine flu shot is a must especially for those with heart problems because flu infection can cause a heart attack."

The H1N1 virus, which has thus far taken lives of 1,600 people in India since its outbreak in 2009, is again spreading in most southern states where the monsoon has set in.

Dr. Balbir Singh, eminent cardiologist in the Medanta Medicity hospital in Gurgaon stated, "When a person is sick, the requirement of blood in the body goes up. This results in increased pressure on heart which is already weak. Due to the persisting ailment, this may also lead to a heart attack."

But Delhi's chemists said they have no stock of the suggested vaccines.

Up till now, the national capital has registered the highest number of 9,700 cases of H1N1 virus since its outbreak in May last year. A total of 95 deaths were reported during the last year.

In 2010, the virus has not shown much impact to date, but specialists feel that the monsoon may worsen the troubles.

A total of three cases were reported from Delhi in the last two months while one death was reported from neighboring Ghaziabad last week.

Doctors said that while A/H1N1 is risky for all, patients of chronic illness are at higher risk as their immune system and other body functions are already weak.

The vaccine is also suggested for patients with other chronic illnesses such as cancer and respiratory problems.

India's first indigenous swine flu vaccine manufactured by Zydus Cadila was launched last month. These vaccines are, however, not recommended for pregnant women and children.

Last week, around 345 new cases of swine flu and 17 fatalities were reported in the country.

Kerala remains the most severely affected state, which reported 266 cases and seven casualties. Maharashtra, Karnataka and Tamil Nadu are other seriously affected states. (With Inputs from Agencies)