Published 07:24 IST, June 15th 2020
ICMR recommends rapid Antigen detection test for COVID-19; issues advisory
The Indian Council of Medical Research (ICMR) has recently released its recommendations for the use of Standard Q COVID-19 Ag detection test.
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The Indian Council of Medical Research (ICMR) has recently released its recommendations for the use of Standard Q COVID-19 Ag detection assay (antigen detection test). According to reports, the test should be performed in certain conditions and should be paired with the RT-PCR test for accurate results.
Antigen detection test must be paired with RT-PCR test
According to the recommendations by ICMR, those individuals who test negative for COVID-19 by rapid antigen test must then undergo the RT-PCR test to eliminate the possibility of infection. But those who test positive must be considered COVID-19 positive and there is no further need to administer the RT-PCR test.
As per reports, the Standard Q COVID-19 Ag detection test can give positive or negative results in as little time as 15 minutes and the results can be read through the naked eye, which means that there is no need for specialised equipment. The maximum duration to wait for test results is 30 minutes after which the testing strip should be disposed off. The ideal temperature for storing the test kits is between 2° to 30° C.
The ICMR recommends that the Standard Q COVID-19 Ag detection assay with its high specificity but relatively low sensitivity be paired with the gold standard RT-PCR test. The following settings are required for a successful test.
A. Containment zones or hotspots (to be performed onsite under strict medical supervision and maintaining the kit temperature between 2° to 30° C.):
- All symptomatic Influenza-Like Illness (ILI).
- Asymptomatic direct and high-risk contacts with co-morbidities (lung disease, heart disease, liver disease, kidney disease, diabetes, neurological disorders, blood disorders) of a confirmed case to be tested once between day 5 and day 10 of coming into contact.
B. Healthcare settings (to be performed onsite under strict medical supervision and maintaining kit temperature between 2° to 30°
- All symptomatic ILI patients presenting in a healthcare setting and are suspected of having COVID-19 infection.
- Asymptomatic patients who are hospitalized or seeking hospitalization, in the following highrisk groups: Patients undergoing chemotherapy, immunosuppressed patients including those who are HIV+; patients diagnosed with the malignant disease; transplant patients; elderly patients (>65 yrs of age) with co-morbidities (lung disease, heart disease, liver disease, kidney disease, diabetes, neurological disorders, blood disorders)
- Asymptomatic patients undergoing aerosol-generating surgical / non-surgical interventions: Elective/emergency surgical procedures like neurosurgery, ENT surgery, dental procedures; non-surgical interventions like bronchoscopy, upper GI endoscopy and dialysis.
The ICMR recommends that the A and B categories can be given the rapid antigen test under the following conditions:
- Suspected individuals who test negative for COVID-19 by rapid antigen test should be definitely tested sequentially by RT-PCR to rule out infection, whereas a positive test should be considered as a true positive and does not need reconfirmation by RT-PCR test.
- Samples (only nasopharyngeal swabs) to be collected by a trained healthcare worker following full infection control practices including the use of proper PPE.
- The test should be conducted onsite under strict medical supervision and within one hour of sample collection in extraction buffer.
The ICMR in its recommendation further added, "Real-time RT-PCR is the gold standard frontline test for diagnosis of COVID19. Various open and closed RT-PCR platforms (Open systems RT-PCR machines, TrueNat and CBNAAT) are currently being used for COVID19 diagnosis in India."
"All these platforms require specialized laboratory facilities in terms of equipment, biosafety and biosecurity. Minimum time taken for the test varies between different systems with a minimum of 2-5 hours including the time taken for sample transportation. These specifications limit the widespread use of the RT-PCR test and also impedes quick augmentation of testing capacity in various containment zones and hospital settings," the recommendation read.
(Input/Image Credit: AP)
07:24 IST, June 15th 2020