COVID-19 PCR TEST INFORMATION MALDIVES YEAR 2022
What’s the difference between Covid-19 test types?
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To diagnose for COVID19, polymerase chain reaction (PCR) tests are sent to a lab.
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Covid-19 can be diagnosed on the spot with lateral flow tests (LFTs), although they aren't as accurate as PCR tests.
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Antibody (or serology) testing can't detect active infection, but they can indicate if someone is immune to Covid-19.
What is PCR Testing?
PCR tests are used to detect viral RNA in the body before antibodies are produced or symptoms of the disease arise. This means that the tests can detect whether or not someone is infected with the virus at an early stage of their sickness.
Reverse transcriptase or DNA polymerase are compounds introduced to a nasopharyngeal sample in a lab during PCR testing. These chemicals function by duplicating any viral RNA that may be present. Because specially designed primers and probes bind to parts of the virus's genetic code to identify the presence of a pathogen, this ensures that enough copies of the RNA are present to deliver a positive result.
PCR provides us a decent indication of who is infected
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Public health experts can acquire a better picture of the transmission of a disease like Covid-19 by scaling PCR testing to screen large numbers of nasopharyngeal swab samples from inside a population.
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However, there are several limitations to PCR.
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Because these Covid-19 tests must be sent to a laboratory for analysis, consumers may have to wait days to get their findings.
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With different PCR tests, false negatives can occur up to 30% of the time, making them more effective for confirming the existence of an illness rather than giving a patient the all-clear.
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They can also produce false positive findings since they're so sensitive that they can detect dead, deactivated virus in the body of someone who has recovered from Covid-19 and report a positive result.
What is Lateral Flow Testing? (LFTs)
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LFTs and PCR testing are both antigen tests, but LFTs are designed to detect active Covid-19 infection rather than antibodies to the disease.
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A nasopharyngeal sample is deposited on a tiny absorbent pad and dragged along the pad by a capillary line to a strip coated in antibodies that bind to SARS-Cov-2 proteins using a Covid-19 LFT.
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If these proteins are present, a coloured line on the test will appear, indicating infection.
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The primary advantage of LFTs over PCRs is that they do not require validation and can produce results in 15 to 30 minutes.
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What they gain in speed, however, they lose in accuracy.
A analysis of 64 research from Europe and the United States found significant differences in accuracy between different LFT brands. The tests were also found to be considerably more effective at detecting Covid-19 in those who had symptoms than in people who did not. In symptomatic persons, LFT sensitivity ranged from 34% to 88 percent, with an average accuracy of 72 percent. LFTs properly identified 58 percent of individuals who were infected among people who had no symptoms.
While the use of LFTs for mass asymptomatic screening has been promoted in nations such as the United Kingdom, experts have questioned the utility of these Covid-19 tests in this context.
What about Antibody Testing?
Wright continues, "An antibody test tells us what percentage of the population is afflicted." Because antibodies are formed after a week or two, the virus should have been eradicated from the system, it won't inform you who is sick. It does, however, reveal who has been infected and who should be immune to the virus."
People who recover from even minor instances of Covid-19 develop antibodies for at least five to seven months, and possibly much longer, according to a study published in the journal Immunity.
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People who survived the SARS (sudden acute respiratory syndrome) outbreak in the early 2000s had antibodies in their blood for years after recovery, according to historical investigations.
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SARS and Covid-19 are both caused by coronaviruses, therefore it's not out of the question that Covid-19 could have a comparable effect.
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"Herd immunity" refers to the fact that if a large enough number of people in a population are immune, the virus will not spread.
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If someone is afflicted, the virus will not be able to spread as long as the others around them are immune."
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Unlike PCR testing, which often employ swabs to detect Covid-19, antibody tests typically utilize blood samples.
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This is because, compared to the respiratory tract, there will be a relatively small amount of Covid-19 circulating in the blood, but a considerable and quantifiable antibody presence in the blood post infection.
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Antibody testing are being used to assess immunological responses in persons who have received the Covid-19 vaccine.
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Researchers are unsure how long vaccine-induced immunity will endure or whether booster shots will be necessary.