More than 700 have children have now been found to be infected with HIV in a huge outbreak in southern Pakistan, making up more than 80 per cent of those who tested positive for the virus.

An outbreak of the virus in Sindh province prompted the World Health Organization to carry out a screening programme, which found 876 people to be infected with the virus - 82 per cent of whom were under the age of 15.

The outbreak, which was first discovered in April, has been described as unprecedented in Asia because of the large numbers of children affected.

The virus, which attacks the immune system and, if untreated, leads to AIDS, is thought to have been spread by unqualified “quack” doctors and sloppy hygiene at clinics.

Reusing needles and poor sterilisation of medical and dental instruments is common in the backstreet clinics which are often the only source of medical care for many Pakistanis.