The World Health Organisation (WHO) experts arrived in Karachi to support the health authorities to deal with the outbreak of HIV in Larkana.
The team was received by Health DG Dr Masood Solangi.
The outbreak was first reported on April 25 and 700 HIV positive cases have been identified. At least 537 children were positive for HIV in Larkana.
Testing is ongoing at the camp providing antiretroviral treatment for children in Larkana.
Health workers are being deployed and more camps are being set up, the health ministry said.
The WHO team is ascertaining the source of the outbreak and controlling it, providing technical expertise and treatment, rapid diagnostic tests for adults and children.