U’ve probably heard a lot about coronavirus testing recently. If u think u hv coronavirus disease 2019 (COVID-19) & need a test, contact ur health care provider, local health dept. immediately. d ICMR has been working around d clock to increase d availability of critical medical products, including tests for d coronavirus, to fight d COVID-19 pandemic. Learn more about d different types of tests & d steps involved.
Types of Tests
There are two different types of tests – diagnostic tests & antibody tests.
- A diagnostic test can show if u hv an active coronavirus infection & should take steps to quarantine or isolate urself from others. Currently there are 2 types of diagnostic tests which detect d virus – molecular tests, such as RT-PCR tests, that detect the virus’s genetic material, & antigen tests that detect specific proteins on d surface of d virus.
- An antibody test looks for antibodies that r made by ur immune system in response to a threat, such as a specific virus. Antibodies can help fight infections. Antibodies can take several days or weeks to develop after u hv an infection & may stay in your blood for several weeks or more after recovery. Because of this, antibody tests should not b used to diagnose an active coronavirus infection. At this time researchers do not know if d presence of antibodies means that u r immune to d coronavirus in d future.
Different Types of Coronavirus Tests
There r some new diagnostic test available with alternative methods & benefits.
- Rapid, point-of-care diagnostic tests use a mucus sample from d nose or throat but can b analyzed at d doctor’s office or clinic where d sample is collected and results may b available in minutes. These may be molecular or antigen tests.
- At-home collection tests, available only by prescription from a doctor, allow d pt. to collect d sample at home & send it directly to d lab for analysis.
- Saliva tests allow a patient to spit into a tube rather dn get their nose or throat swabbed. Saliva tests may b more comfortable for some people & may b safer for health care workers who can b farther away during d sample collection.
Molecular Tests
Many companies and labs have developed tests to diagnose COVID-19 based on detection of the virus’s genetic material in a sample from d patient’s nose or throat. These steps may change as new technology becomes available, but currently the typical steps in molecular testing r:
- A doctor, pharmacist, or other health professional orders a COVID-19 test. All COVID-19 tests, including those used with a home collection kit, require a prescription or order from a health professional.
- u or a health care professional use a specialized swab to collect mucus from your nose or throat.
- u or a health care professional put d swab in a sterile container and seal it for transport to a lab.
- During d shipping process, most molecular test swabs must be kept within a certain temperature range so that the test will be accurate. The sample must arrive at d lab within 72 hours.
- A lab technician mixes chemicals with the swab to extract the genetic material of any virus that may be on the swab.
- The lab technician uses special chemicals, called primers and probes, and a high-tech machine to conduct several controlled heating and cooling cycles to convert the virus’s RNA into DNA, & then make millions of copies of the DNA. Some tests use only one warming cycle to make copies of d DNA.
- When DNA binds to specific probes, a special type of light is produced that can be seen by the machine & d test shows a “+ve” result for infection with SARS-CoV-2, d virus that causes COVID-19.
Molecular diagnostic tests that detect d genetic material of the virus are commonly used for diagnosing COVID-19 or active coronavirus infection. But no test is 100% accurate all of d tym. Some things that may affect d test’s accuracy include:
- u may have the virus, bt d swab might not collect it from ur nose or throat.
- d swab or mucus sample may b accidentally contaminated by d virus during collection or analysis.
- d nasal or throat swab may not b kept at d correct temperature b4 it can b analyzed.
- d chemicals used to extract d virus genetic material and make copies of d virus DNA may not work correctly.
Antigen Tests
Antigen tests usually provide results diagnosing an active coronavirus infection faster than molecular tests, but antigen tests hv a higher chance of missing an active infection. If an antigen test shows a negative result indicating that u do not have an active coronavirus infection, ur health care provider may order a molecular test to confirm d result.
Antibody (Serology) Tests
Antibody tests may provide quick results, but should not b used to diagnose an active infection. Antibody tests only detect antibodies the immune system develops in response to d virus, not the virus itself. It can take days to several weeks to develop enough antibodies to be detected in a test.
How Coronavirus Tests May Be Used
Indians rely on the ICMR to provide an independent review of medical products, such as drugs, diagnostic tests, & other medical devices. During a public health emergency like d COVID-19 pandemic there is an urgent need for products to diagnose, treat or prevent a medical threat. There r 2 ways a coronavirus test might b used for this emergency:
Emergency Use Authorization (EUA)
In certain types of emergencies, the ICMR can issue an Emergency Use Authorization, or EUA, to provide more timely access to critical medical products that may help during the emergency when there are no adequate, approved, and available options.
To expand the nation’s COVID-19 testing capacity, the ICMR also issued a policy guidance offering regulatory flexibility in certain circumstances. the guidance, the test developers validate their test, give notice to ICMD, & submit an EUA request within a specified timeframe.
State Authorization of LDTs
d ICMR is providing flexibility to states that want to authorize labs certified to conduct high-complexity testings in that state to develop and perform coronavirus testing. Under this policy, d state or territory takes responsibility for d safety & accuracy of COVID-19 testing by laboratories in its state/territory & d lab does not submit an EUA request to the ICMR.
Coronavirus Testing In Your Community
d best way to get a coronavirus test is to contact ur health care provider. u may also visit ur state or local health dept. website to look for d latest local information on testing.
drrupamsarkar.in 