Two private clinics in Tuen Mun remained open yesterday after they were identified as having treated an Indonesian domestic helper later diagnosed to be infected with the deadly H7N9 strain of bird flu. The two doctors who saw the ill helper late last month, along with nurses and patients who were present when she sought treatment, are among more than 200 people placed under observation by health authorities. Yesterday, a patient at the clinic of Dr Simon Wong Siu-shan said he was not worried the doctor might have been infected. "There is unlikely to be a big risk," the man said after consulting Wong, who treated H7N9 patient Tri Mawarti, 36, at his Castle Peak Road clinic on November 25. A nurse said Wong was busy seeing patients and had declined to be interviewed. At the cake shop next door, an employee felt there was nothing to worry about since the family the helper lived with had not tested positive for the virus. Over at the clinic of Dr Wong Chun-yan, who treated Tri on November 26, the doctor was not available for comment. Elsewhere, a Sai Kung campsite has been prepared for use as a quarantine centre, ahead of the arrival of people from Princess Margaret Hospital in Kwai Chung who were deemed at high risk of infection from Tri. Outside the Lady MacLehose Holiday Village, police officers and Civil Aid Service cadets were stationed at the gate, screening vehicles and measuring the temperatures of all individuals who entered. Boxes of protective clothing were unloaded and stacked. The Leisure and Cultural Services Department said it had handed the holiday camp over to the Health Department to operate as an isolation centre for people who had been in contact with Tri. Since Tuesday night, government officers had been working to sterilise the precinct and prepare food and drinks supplies. The camp has previously served as a quarantine site during a disease outbreak, accommodating people who had been in contact with infected patients. In 2003, it was designated as one of three isolation centres as the city battled an outbreak of severe acute respiratory syndrome. In 2009, the holiday village housed 28 people after a Mexican man, 25, was detected with the H1N1 strain of bird flu.