A 37-year-old Filipino maid has become the second person in Hong Kong to die of swine flu, but the first without underlying conditions. An expert said a delay in seeking treatment had been a big factor in her death. The woman, who had been in intensive care in United Christian Hospital for more than two weeks, died at about 6pm yesterday. She arrived in Hong Kong on June 28 and fell ill the next day with a sore throat and fever, but she only went to see a doctor more than a week later, on July 7. She was admitted to intensive care and confirmed with swine flu on July 11. She was a non-smoker, was not overweight and had no underlying medical conditions, the Centre for Health Protection said. The hospital had referred the case to the coroner and contacted her family, employer and the Filipino consulate. There were 153 new cases yesterday, taking the total to 2,855. Forty-two people were receiving hospital treatment, four were in critical condition and one was in a serious condition. The new cases included three nurses - one each from Kowloon Hospital, Princess Margaret Hospital and Prince of Wales Hospital - and a doctor from Queen Mary Hospital. They were all stable. An expert in respiratory medicine at Chinese University, David Hui Shu-cheong, said a delay in seeking help had been a major factor in the Filipino woman's death. 'Drugs are most effective on the first two days after the onset of symptoms,' Professor Hui said. 'After a delay, the virus starts to attack lung tissue, and might lead to multiple organ failure.' He said people should watch out for shortness of breath, as that was a sign of lower respiratory tract infection that could cause pneumonia. They should also see a doctor as soon as possible if their fever did not subside within two days. But he said the public should not panic as the city's death rate of 0.0007 per cent was much lower than the World Health Organisation's world average of 0.4 per cent. University of Hong Kong microbiologist Ho Pak-leung said employers should give domestic helpers sick leave if they showed flu symptoms, and he was worried that many maids might be deterred from seeing a doctor for fear of losing their jobs. He also urged the government to release more analytical statistics on the severe cases, as it was no longer enough just to publish the daily tally.