Swine flu virus called Pandemic influenza A(H1N1) pdm9 was detected in Nepali capital and three other districts outside the capital, doctors at the Sukraraj Tropical & Infectious Disease Hospital in Kathmandu said Wednesday.

Doctors confirmed the outbreak of the swine flu virus after the virus was detected in blood samples collected in the capital and the country's mid-western districts of Chitwan, Sindhuli and Khotang.

Prior to this, H1N1 virus was seen in Nepal in 2009.

Doctor Gita Shakya, director of the National Public Health Laboratory of Kathmandu, said that people don't have to be worried about the disease as it can be cured if found in the preliminary stage.

Dr. Shakya said the reason behind the resurgence of the virus in Nepal is that several districts of the country have recently been suffering from viral fever.

Doctors said so far over a dozen people died due to viral fever outbreak in Nepal.

"Of the total 24 deaths from viral fever, some of them might have been died due to late diagnosis of the swine flu virus,"Dr. Shakya said.

According to Dr. Shakya, they have detected the swine flu virus from the laboratory tests based on polymerase chain reaction (PCR) rather than tests based on rapid kits.

Dr. Sher Bahadur Pun at the Infectious Disease Hospital said some patients have also been diagnosed with both type of influenza A and B of swine flu virus which are dangerous.

The virus usually strikes children and young people who have low immune capability against minor diseases.

In 2009, over 40 people were killed during the outbreak of the virus in Nepal.