The Indian Council of Medical
Research(ICMR) approved one more kind of
test for diagnosis of Covid-19.The rapid antigen detection test is to be used in
specified settings, and kits from only one manufacturer have got approval.
What
is the rapid antigen detection test for Covid-19?
It is a test on swored dense
samples receiving antigens (foreign material showing an immune response)
obtained from the SARS-CoV-2 virus. It shows care, which is done outside of the
normal lab area, and is used to get a fast diagnostic result. In India, ICMR
has approved the use of antigen detection kits produced by South Korean company
SD Biosensor. The kit, called the Standard Q COVID-19 discovery Kit, comes with
a built-in Covid test tool, a viral tubing tube with viral analysis buffer and sterile
lab for sample collection.
How
is it different from the RT-PCR test?
RT-PCR is currently the
standard gold frontline assay for the detection of Covid-19. Like RTPCR, a
rapid antigen detection test also seeks to detect the virus rather than
antibodies produced by the body. While the methodology is different, the most
important difference between these times is time. As the ICMR has shown, RT-PCR
testing takes at least 2-5 hours including the time taken for sample transport.
at various referral centers and hospitals. In a reliable rapid antigen detection test,
the duration of translation for a positive or negative test is 30 minutes.
Why
has only the kit by the company SD Biosensor been allowed?
There are very few reliable
antigen diagnostic material for Covid-19 diagnosis available worldwide. On May
9, the US Food and Drug Administration (FDA) approved the first antigen test,
with a US-based Quidel antigen called Sofia2SARS Antigen FIA.OnMay14, Japan's
Department of Health, Human Resources and Social Services authorized the use of
Tokyo's Fuyorebio Inc. antigen testing kit.
In India, ICMR has conducted
independent testing of two SD Biosensor kit sites, ICMR and AIIMS. The results
revealed that the kit had the highest precision, or the ability to detect true
anomalies, ranging between 99.3% and 100% for the two sites. The sensitivity of
the test, or its ability to get real results, is between 50.6% and 84%,
depending on the patient's viral load. When an increase in the ability to
detect a true negative, a reliable one has any positive effect. As we allowed
SD Biosensor to sell its kit commercially, ICMR also requested other
manufacturers / developers who received antigen coverage as saying they would
come with it.
Where
will the test be used?
Currently, the kit will be used
in hot spots and health care settings. In both cases, ICMR, has warned that
testing will be done under strict medical supervision and to keep the cat's
temperature between 2 ° and 30 ° C. In content areas, tests can be performed on
all flu-like illnesses. Direct contact with Asymptomatic Risks by
co-morbidities (lung disease, heart disease, liver disease, kidney disease,
diabetes, neurological disorders, blood disorders) of the confirmed case should
be evaluated once between 10 and 10 days of contact.
In health care settings, it can
be used in three stages. First, of all people presenting flu-like symptoms in a
health care setting and allegedly having Covid-19 infection; secondly, in
asymptomatic patients hospitalized or in need of hospital admission, in these
high-risk groups - those chemotherapy, concentrated patients including those
with HIV, patients diagnosed with pain, allergies, elderly patients (over 65)
with co-morbidities -For third, in asymptomatic patients who undergo
aerosol-free surgical interventions such as surgical / emergency procedures
such as neurosurgery, ENT surgery, dental procedures, and non-surgical
interventions such as bronchoscope and dialysis.
Is
the test a confirmatory one for diagnosis of Covid-19?
According to the ICMR guidelines,
if the test shows a positive result, it should be considered as true positive,
and does not need reconfirmation. However, those who test negative in the rapid
antigen test should then be tested by RT-PCR to rule out infection.
What
are the limitations of an antigen test’s results?
In granting the urgent approval
of the first antigen kit, the US FDA pointed out that antigen testing was
highly specific for the virus, but not for PCR testing of as sensitive.
"This means that good results from antigen tests are very good, but there
is a high chance of being negative, so side effects do not exclude infection
.To mind, the negative effects of antigen testing may need to be confirmed
through PCR testing before making medical decisions or stopping the increase.
The virus may be due to false infidelity, "the USFDA said.
Also, ICMR said that when a
sample was collected in a output buffer, it settled for only one hour.
"Therefore, antigen testing needs to be done in a sample collection center
where healthcare is provided," the ICMR said. SD Biosensor said that a
negative test result could result if the level of antigen released at the
guessing level is below the inspector's sensitivity if the low quality
detector; an adverse effect may also occur if the antigen concentration in the
sample is below the limit of the test or in the study. Also, the company points
out, children tend to shed the virus longer than adults, which may result in
sensitivity differences between adults and children.