The swine flu pandemic may remain mostly mild in its effects, but it is likely to get worse before it gets better. The World Health Organisation expects a second, bigger wave of infections as the peak northern hemisphere flu season approaches, with the ever-present risk of mutation in the virus that could present a more serious threat. WHO chief Dr Margaret Chan Fung Fu-chun says health authorities should scale down border controls and laboratory tests on the new virus and focus more resources on treating patients to head off complications. Evidence is growing that antiviral drugs such as Tamiflu and Relenza can stave off the worst effects of the disease. And Chan says clinical trials of vaccines suggest a single dose, rather than two as expected, will protect healthy adults. That is good news for Hong Kong. The government was tardy in putting out an international tender for supply of five million doses. When it did, it received no offers deemed to meet requirements. Now it is repeating the exercise on a more flexible basis, including provision for supply from more than one maker, which could shorten delivery lead time. But Hong Kong could still be well down the queue for delivery. Secretary for Food and Health Dr York Chow Yat-ngok says that as a last resort, the city can take up an offer of help from the mainland, where drug makers have won approval to distribute vaccines intended only for domestic use. This would represent a departure from the conditions of the tender, which stipulate safety approval from the therapeutic drugs authorities in the United States, the European Union or Australia. China, however, is seeking registration with the WHO under a 'pre-qualification' scheme for developing countries. It cannot be ruled out that our city will have to face the second wave without timely access to enough of the vaccine. In that case Chan's advice to switch the emphasis to treating patients makes even more sense. The government also cannot afford to relax its efforts to promote community awareness of prevention and control measures, including personal hygiene and early treatment.