The outbreak is almost certainly the fault of more than one doctor, health officials said. Lax safety rules and the reuse of syringes or needles happen among both the town's registered medics and unregistered quacks.

Medical waste is not safely disposed of and syringes are even recycled in the bazaar and sold again. Unsterilised dentists instruments and barbers' razors, and poorly regulated blood-transfusions all add to the risks of spreading blood-borne diseases.

The number of new infections has now slowed to one or two each day, but as the initial panic subsides, health officials are left with the question of how to stop the spread of the infection and how to treat those who have it.

Medics at Pakistan's AIDS Control Programme admit they were overwhelmed to start with. There were not enough medicines or staff to address the crisis. Parents complain they were not receiving medicine and have to travel 20 miles from Ratodero to Larkana to get drugs.

Health officials now deny there is a shortage, and say a clinical service to treat patients is being set up from scratch. More than half of patients are receiving antiretroviral drugs and the rest will be as soon as they are treated for other infections like TB.

Yet despite the reassurances, an estimated 25 HIV positive children have already died since they were diagnosed, in an area already hit by malnutrition and high infant mortality. Treatment for AIDS is patchy at best in Pakistan, with the United Nations estimating 6,400 died from the disease last year.

Dr Sikander Ali Memon, director of Sindh's AIDS control programme, said: “Not all the patients have been provided all the treatment because certain people have prior infections, like TB. When they get cured of those, they will start treatment of HIV.” He said so far 600 are on antiretroviral drugs.

He said a public information campaign would run to try to remove some of the stigma surrounding infection, which many still associated with sex or drugs.