Sir

The Commentary article “Lessons from the past” by Z. Dong and colleagues (Nature 433, 573–574; 2005), on China's public-health system, has touched upon an urgent issue that may influence the course of China's future. Their attempt to apply such lessons in today's China, however, may require a deeper look at the fundamental changes that have taken place in the country from one era to the other.

The “glorious beginning” under Mao's regime might have been due more to totalitarian control, with communities isolated and movement restricted, than to the health-care system at that time. Although that may have been more fair than today's system, it was at least as inadequate.

The serious medical problems facing today's more open and free China did not have the chance to flourish during that earlier period. Contrast the early 1980s, for example, when sexually transmitted diseases were rare, with the present, when HIV/AIDS has reached epidemic status in parts of the country.

Prevention is the key to public health. But remedies from the past should not be relied on to solve a crisis today, when one is confronted with totally different problems in a totally different society.