The health body also pinpoints another possible cause of the Metropole outbreak A Sars outbreak similar to that which claimed 35 lives at the Amoy Gardens housing estate could happen again if the same 'unlucky' circumstances are repeated, the World Health Organisation says. A WHO team of environmental consultants yesterday also revealed that the man who triggered the initial outbreak at the Metropole Hotel may have infected others by vomiting in a hallway. The team's initial findings confirmed much of what local health officials had already said. 'It is highly likely that an unlucky set of environmental and health events happened simultaneously [at Amoy Gardens],' the WHO's environmental health team leader, virologist Heinz Feldmann, said. 'I do believe it can happen again if we go back to the same situation. The international community looks at this as an eye-opener. You can do a lot to prevent it.' The four-man team arrived on April 27 and conducted on-site visits, inspecting construction, plumbing and ventilation systems, and taking air samples. The final report will be submitted to the government and the WHO on May 31. The Sars virus was brought to Block E of Amoy Gardens in Kowloon Bay by a sick man visiting his brother in late March. The man, who had diarrhoea, spread the virus via the sewage system, as did other subsequently infected victims. The WHO backed up a Hong Kong investigation's findings that when residents used their bathrooms with doors closed and exhaust fans open, the virus was sucked into the room through dried-out U-traps. The toilet flushing system was also shut down for 16 hours on March 21 to fix a broken pipe. 'Exhaust fans in bathrooms were running with the door closed and contaminated droplets could have been drawn from the soil stack into the bathroom through the dried-out floor drains,'' Dr Feldmann said. This allowed viruses to enter other apartments via open windows, even several floors away from the source. The team also carried out a full investigation at the Metropole Hotel, where a sick Guangdong doctor passed the virus on to guests on the ninth floor, sparking off the global Sars outbreak. The probe found 'a horizontal spread [of the disease] on one wing of one floor' of the hotel, with the contamination occurring in the hallway. This indicated there was no problem with the hotel's sewage and ventilation systems. 'The index patient was already quite sick and he may have vomited. We learned here that spitting is a problem. There has been a contamination of some source in the hallway that then has infected the other people. That is the only explanation. People who were in their rooms at that time were basically protected,' Dr Feldmann said. He said he could not comment on whether the WHO would lift its advisory against travel to Hong Kong, adding that such a ruling would be a 'political decision' made by the WHO. WHO spokesman Peter Cordingley said it was too soon to say whether the report would affect the travel advisory. A tale of two outbreaks: what the WHO team concluded Amoy Gardens An infected man transferred the disease into the building's sewage system Bathroom exhaust fans sucked the virus up through dried-up floor pipes The fans then blew the virus into the light well and into open windows The Metropole Hotel Infections were 'horizontal', ie: restricted to one floor, meaning the sewage or ventilation systems were probably not involved. Contaminations occurred into a hallway Investigators theorise the virus carrier may have vomited or spat on the ground
