NEW DELHI: Amid the rising cases of Dengue in the city, the officials are wary of the missing or under-reported cases of the vector-borne disease propelled by the use of less efficient tests which many private medical practitioners are using to detect the mosquito-genic virus.
According to them, the reason behind the issue is the less availability of government-prescribed test kits in the market. The senior officials have flagged that due to the dearth of ELISA kits, many clinics and hospitals are using rapid diagnostic kits (RDT) to confirm dengue fever. They also said that such kits may also give false positive cases.
Officials cautioned that the reliability of rapid kits has been questioned and the Centre has asked states to discourage its use in detecting dengue in a review meeting with states held earlier this year. “The sensitivity of RDT is not reliable. We are not supposed to take RDT into consideration because these kits are not validated. We have flagged this issue with the private hospitals and clinics. It’s also against the government guidelines,” a senior health official informed.
A meeting between municipal health officials and members of the Delhi Medical Association (DMA) also happened on Monday to discuss the matter in detail. Officials said that the apex medical body of private practitioners in the city will circulate the messages across its member's clinics and hospitals. According to the guidelines issued by the National Vector Borne Disease Control Programme (NVBDCP), a case compatible with the clinical description of Dengue fever should be tested with at least one of the following:
Demonstration of Dengue virus antigen in serum samples by NS1 ELISA; Demonstration of IgM antibody titre by ELISA positive in single serum sample; Detection of viral nucleic acid by polymerase chain reaction (PCR); Isolation of the Dengue virus (Virus culture +VE) from serum, plasma; IgG seroconversion in paired sera after 2 weeks with a four-fold increase of IgG litre.
“The blood samples of all dengue-suspected cases have to be sent to the Sentinel Surveillance Hospital (SSH), to be tested by ELISA technique. A patient can be declared positive for Dengue only on the basis of ELISA technique of testing and not by RDT,” the government guidelines specified.