Hyderabad: Rapid diagnostic tests for malaria are being extensively marketed and used and these are showing false positives as only a microscope-based test can validate and confirm the load of parasites, drug controllers said.
Misuse of these diagnostic kits and heavy marketing has led to complaints to the drug controller department about these kits and there has been a demand to regulate it.
A senior drug controller on condition of anonymity said, “The manufacturers are making low-cost malaria antibody IVD kits for rapid diagnostic tests of the disease. These are being heavily relied upon but they do not give the exact parasite load. The 100 per cent sensitivity to detect malaria is not present in these kits.”
According to the World Health Organisation, only a microscope-based test can validate and confirm the parasite load in the human blood to confirm malaria.
The WHO standards state that parasite load of 50 to 100 per micron of blood can help to confirm but by a microscope-based test only. The rapid diagnostic antibody kits were to manage malaria medically once confirmed to understand the load of the various parasites.
The RDT’s are for specific antigens either p falciparum or p vivax and other multiple species which cause the infection.
Dr Mohammed Rafi, senior general physician with Osmania General Hospital said, “The RDT is used as the first step and then the blood samples are sent for microscopic testing. The first testing is done to start the malaria treatment. The load of the virus is ascertained in the microscopic test. Only those patients who come from areas which are not identified as malaria zones are not starting the treatment. The RDT so far has helped to control and manage the disease properly.”
A senior drug control officer explained, “We have got complaints that the manufacturers are using fewer antibodies in the testing kit which is leading to reduced costs. Due to this reason, there is a doubt that there is improper screening of malaria. In the urban areas, the tests are being reconfirmed but in rural areas, there are no confirmation tests and that is leading to wrong treatment.”
