The Cotugno, which specialises in infectious diseases, is the only public institution in southern Italy which accepts Aids patients, but over the past two years it has become a byword for mayhem and the deep malaise at the heart of the Italian health system. The crisis reached its peak four days ago, when an Aids patient died of a heroin overdose and two others were whisked into intensive care. They, too, had bought the drugs on the premises.
The police were ordered in by the local government prefect, Achile Catalani, on the advice of the health and interior ministries. "We don't intend to turn the place into a military camp," Mr Catalani said. "But there will be at least two law officers on site at all times to ensure full surveillance around the clock."
The Cotugno was originally intended to be part of a new wave of health care in the Naples region, a clean, efficient hospital providing well- administered specialist care - in stark contrast to the main general hospital, the Cardarelli, where rats have the run of the wards, bodies mysteriously disappear from the morgue, and patients have been known to die because the operating theatre ran out of stitching thread.
Only last week, a 15-year-old boy infected with botulism from a rogue tub of mascarpone cheese died at the Cardarelli because the authorities had forgotten to check supplies and were unable to treat him.
Unfortunately, the Cotugno has never lived up to its hopes of being significantly different, and its Aids wards have rapidly run out of control, partly because the patients are nearly all drug addicts with violent, if not criminal, tendencies, and partly because the numbers have become too big to handle.
In March last year, Aids patients rebelled against their conditions by flinging furniture and food out of the windows. They were provided with new beds and television sets, but the improvements turned out to be little more than window dressing. Two new Aids wards have been opened since, but without the resources to provide even a minimum level of civilised care.
A week ago, a doctor almost died when a patient set fire to a mattress and tossed it into his office. Nurses complain that they are attacked with blood-stained needles. It has been an open secret that drugs pushers do the rounds of the wards during visiting hours. But this is also a city where many hospital orderlies are ex-convicts helped into public- sector jobs by the local Mafia, which in turn controls the drugs trade.
Staff have little faith that the police presence will change much. "It will last two weeks," predicted one nurse. "Then, when the media fuss has died down, it will be hell all over again."