Prostitution is like prairie grass which isn't killed in a fire.

No one can say for sure the current crackdown on the sex trade in the city of Dongguan in South China's Guangdong province, a city long known for its hotel sex trade, will deal it a fatal blow there.

Now the Ministry of Public Security has called for a severe crackdown on prostitution, gambling and drug-related crimes by all its local counterparts.

Such a nationwide crackdown is definitely justifiable as prostitution is illegal in China and anyone who organizes prostitution can be arrested. Prostitutes caught doing business can be detained and fined according to regulations on the maintenance of social order.

But what we have heard from the ministry officials about relentlessly punishing police officers who provide protection to prostitution or turn a blind eye to such crimes sounds all too familiar. It is what we have heard every time a similar crackdown has been waged.

This time some police officers in Dongguan have received penalties and the city's police chief was dismissed from his post because the prostitution was so rampant.

But we wonder how long this campaign will last and whether the city's sex trade will stage a comeback after the crackdown has ended.

Rome was not built in a day. It certainly took some years for Dongguan to gain its fame as the country's sex capital. Why did the local police and government do nothing to curb it before it acquired such a reputation?

Dismissal of the local police chief and several police officers is not enough and fails to take into account the local government's role.

Neither are detaining of hundreds of prostitutes and closing some of the hotels and nightclubs involved in the sex trade enough to hail the crackdown as a triumph.

Since prostitution is illegal, what is needed is a permanent crackdown mechanism to leave as little space as possible for its existence, so that the spread of HIV and other sexually transmitted diseases can be brought under control.

Past campaigns have followed a similar pattern with prostitutes rounded up and their organizers apprehended, along with several police officers who provided protection, But quite often prostitution stages a comeback.

We hope this campaign can be different, but a permanent crackdown mechanism needs to take root.