A division bench of Acting Chief Justice Bhaskar Bhattacharya and Justice J B Pardiwala issued the notice while hearing a PIL filed by Advocate Girish Das.
The state is to file its reply by June 14.
The Assistant Superintendent of Police, Junagadh, recently submitted a probe report to the High Court. But the judges were not satisfied with the findings, the petitioner said.
The court asked the investigating officer to stop the probe and keep all the documents in his personal custody.
The case came to light when 23 thalassemic children tested positive for HIV, allegedly due to failure of authorities to ensure supply of non-contaminated blood.
Thalassemia patients need periodic blood transfusion.
