Covid Tests
Tests aren’t perfect, of course, and can produce false negatives and positives. But they provide a critical window into the activity of a pathogen too small to see - Emily Anthes
image by: Lake County Colorado COVID-19 Information
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How Confident Can You Be in a Coronavirus Test?
In mid-November, David Piegaro tested positive for the coronavirus. His results came too late.
The night before, Mr. Piegaro, a member of the National Guard, drove to New Jersey to visit his family after receiving two negative rapid test results, two days in a row. By the next morning, he had left. But the single overnight stay was enough to spread the virus Mr. Piegaro was unknowingly carrying to multiple members of his family, including his grandfather, who ended up spending two weeks in the hospital.
“Those two negative results gave me more confidence than I should’ve had that I could see my grandfather,” Mr. Piegaro said.
Since the start of the pandemic, the…
Resources
COVID Tests Weren’t Designed for This
Testing is so complicated because we’re asking it to do too much.
Stop Wasting COVID Tests, People
With the surge in cases, tests should be reserved for those who need them most.
Covid testing: The best at-home rapid test kits
Testing at home can provide peace of mind, and it doesn't have to take a long time or be terribly expensive.
How Reliable Are COVID-19 Tests? Depends Which One You Mean
Here's a quick guide to sorting out the pluses and minuses to each type of test.
Where to Get Home COVID Tests and Why They’re So Hard to Find
In many Asian and European countries, at-home COVID-19 tests are cheap and easy to find in stores. CBS News reported that home antigen tests are now used routinely in the U.K., where they are free and “readily available at pretty much every pharmacy in the country.” The situation is drastically different here because U.S. health officials focused on getting people vaccinated against COVID-19 and never leaned into asymptomatic testing as a strategy to fight the pandemic.
A Covid Test as Easy as Breathing
Scientists have been dreaming of disease-detecting breathalyzers for years. Has the time for the technology finally come?
At-Home Coronavirus Testing Is Here
These tests are not nearly as accurate as those taken in a clinic, but experts say coronavirus tests that can be done at home play an important role as the country continues to reopen.
COVID testing FAQ: When to test, what kind of test to use and what your results mean
The end result is a lot of confusion about testing and a lot of frequently asked questions. Here are some answers to queries you might have about COVID-19 tests.
Covid tests are complicated. A guide to understanding types and trade-offs
If you need a Covid-19 test, you have options. But what type of test is best? And what are the differences? Terms like molecular, antigen, rapid, PCR, RNA can be head-spinning when you often just want to know the answer to one question: positive or negative? The differences in tests pertain to what they are looking for, how sensitive they are, as well as how fast they produce results and how much they cost.
We vetted popular at-home COVID-19 tests. Here’s what we learned
Everything you need to know about the growing number of at-home testing options for COVID.
You Could Have COVID Symptoms and Still Get Negative on a Rapid Test. (It’s Actually Good News!)
Basically, the vaccines enable the immune system to detect the virus more quickly. Symptoms may therefore appear earlier, when levels of the virus are still too low to be detected by a rapid test. The discordance between symptoms and test results may seem scary, but it’s a promising sign that the vaccine has effectively fortified the immune response.
Are We Getting COVID Testing All Wrong?
It may be time to reimagine how we use tests in the U.S.
Coronavirus Variants Have Nowhere to Hide
Our tests will need frequent touch-ups to make sure that no mutations get past them.
COVID Tests Weren’t Designed for This
Testing is so complicated because we’re asking it to do too much.
Why the Coronavirus Test Gives So Many False Negatives
That doesn’t mean the COVID-19 test itself is a failure. But its imperfections do have serious implications for how we manage the pandemic. We need more research to better understand how the coronavirus appears in different parts of the body and at different times throughout the illness.
A negative Covid-19 test isn’t an all-clear
What is the probability of testing positive for Covid-19 before you get symptoms? Scientists really don’t know.
Access to at-home COVID-19 tests will soon become way easier
But going to a clinic for a PCR test is still a better option in some cases.
Affordable Coronavirus Tests Are Out There, if You Look
“It still is too expensive for the typical American household to be rapid testing everyone in the household every week,” said Zoe McLaren, a health policy expert at the School of Public Policy at the University of Maryland, Baltimore County. With the holidays fast approaching, are there ways to reduce the financial burden of testing? There are, but they may require both legwork and luck, experts said.
Catching Covid-19 after being vaccinated isn’t a myth. It happened to me
My experience shows that testing for Covid-19 isn’t perfect. Rapid antigen tests detect proteins that are part of SARS-CoV-2, the virus that causes Covid-19. They have a fast turnaround time, but aren’t as accurate as the gold-standard PCR test. In people with Covid-19 symptoms, rapid tests correctly detect the virus only 80% of the time. In those without symptoms, it drops to 40%. PCR tests, in contrast, tend to have much higher sensitivities, above 95% across the board.
Companies ditch plans for rapid spit tests at home
The technology for rapid saliva-based coronavirus tests that could be used at home is not panning out the way some have hoped.
Coronavirus tests are pretty accurate, but far from perfect
Widespread testing for the SARS-CoV-2 virus is important to both slow the virus and gain information about how widespread it is in the U.S. But a second aspect of testing has gotten less attention: accuracy. It’s surprisingly hard to determine how accurate a coronavirus test is, identify the cause of any inaccuracies and understand how inaccuracies affect the data public health officials use to make decisions.
Could a souped-up version of existing Covid-19 tests be our shortcut to tracking variants?
Genomic sequencing is one of the best defenses against potentially deadlier or more transmissible variants of the coronavirus. It’s also expensive, slow, and currently almost nonexistent in the United States. So some epidemiologists are advocating for an easier, cheaper, and faster way to help track variants’ paths through the country: a souped-up version of widely available Covid-19 diagnostic tests that can flag samples with any problematic genetic tweaks.
Covid-19 Testing Could Be a Viable Long-Term Business Bet
Companies, government spend billions to develop tests in a bet they will be crucial to resuming normal life if large numbers remain unvaccinated
Even Covid-19 tests that aren’t perfect can help control the pandemic
Test characteristics are usually reported in terms of their sensitivity and specificity. Sensitivity, sometimes called the true positive rate, tells you what percentage of people who have the disease you are testing for (like Covid-19) will test positive. Specificity, sometimes called the true negative rate, tells you what percentage of people who don’t have the disease will test negative.
FDA Approves 1st At-Home Coronavirus Test
Until now, people have had to visit a doctor's office, clinic, hospital or some other site to have a sample taken or they could collect a sample at home for mailing to a lab for analysis.
FDA finds 3 COVID-19 tests that fail to detect the omicron variant
FDA has identified three COVID-19 molecular tests that are not able to detect the omicron variant and warned that the diagnostics from Applied DNA Sciences, Meridian Bioscience and Tide Laboratories will return false negative results.
How children are spoofing Covid-19 tests with soft drinks
The acidity of many soft drinks and fruit juices can lead to false positives in the Covid-19 lateral flow test but still be negative with a PCR test
How to determine the accuracy of a Covid-19 test
However, with test results comes potentially false confidence. Because just as with antibody tests, there is always a chance the Covid-19 diagnostic test results will be incorrect.
No, a Negative Coronavirus Test Does Not Mean You Can Safely Socialize
A negative test is helpful, scientists and doctors say. But it doesn’t mean you should skip other measures, like quarantining, masking and distancing.
Rapid vs. PCR COVID-19 testing
... a negative rapid test result should be treated as presumptive, as the test is not as sensitive as a PCR test. With this consideration, it does not rule out a COVID-19 infection and should not be used as the sole basis for treatment or patient management decisions. If a patient is symptomatic or has had high-risk exposure but tested negative in the rapid test, it is recommended that the patient follow up with a PCR test.
The FDA Authorizes a Cheap, Fast Saliva Test—and the NBA Is Involved
SalivaDirect uses spit instead of swabs to test for the coronavirus. Experts say it could be key to increasing the nation’s testing capacity.
The Latest in Coronavirus (COVID-19) Testing Methods and Availability
The amount of information coming out about new test development — from at-home testing to portable/point-of-care tests with faster results — can be overwhelming, and it may be difficult to keep track of when and where these tests will be available...
The Way We Think About COVID Testing Is About to Change
But you probably haven’t had your last nose swab.
Want a Covid Test With Your Viagra?
A health care company known for hair loss and erectile dysfunction treatments diversifies its product line, and earns new fans along the way.
What if We Worried Less About the Accuracy of Coronavirus Tests?
Accuracy is everything, typically, when we take a diagnostic test — an incorrect result can lead to anguish and erroneous, if not harmful, treatment. Currently the most reliable way to identify a coronavirus infection is by a polymerase chain reaction (P.C.R.) test: A swab, usually taken from the nasal passage, produces a sample that is then sent to a specialized laboratory. P.C.R. tests, which can detect minute amounts of genetic material from the virus, cost upward of $100; in ideal circumstances, they take just hours to analyze. But because of high demand, supply shortages and other issues, many commercial labs are taking more than a week to process them.
What Kind of Covid Test Should I Get? Answers on Cost, Accuracy and More
A guide to the common types of tests out there and the differences between them.
What You Need to Know About Getting Tested for Coronavirus
We asked some of the nation’s leading experts on testing to help answer common questions about how to get tested, what to expect and what the different tests and results really mean. Here’s their advice.
Where Are the Tests?
Other countries are awash in Covid tests. The U.S. is not.
Which test is best for COVID-19?
The many types of tests available are sowing considerable confusion. Unfortunately, because this novel coronavirus is indeed novel, and COVID-19 is a new disease, information about these tests is incomplete and the options for testing keep changing. But here’s what we know now about tests designed to diagnose a current infection, and those that show whether you previously had the virus.
Why False Positives Merit Concern, Too
False negatives are not the only troublesome outcome of a faulty coronavirus test.
Why rapid COVID tests are in short supply in the U.S.
The very delayed U.S. rollout of rapid, easy-to-use COVID tests that has confounded public health experts. With surges rolling across the country, prompting more hospital overcrowding, the Biden administration has once again come under pressure for not increasing widespread availability of at-home tests.
Your Coronavirus Test Is Positive. Maybe It Shouldn’t Be.
The usual diagnostic tests may simply be too sensitive and too slow to contain the spread of the virus.
How Confident Can You Be in a Coronavirus Test?
Things like which kind of test it was, and the reason for taking it, should factor into how much credence to give a positive or negative result.
5 things to know about at-home COVID-19 tests for travel
Not all take-home COVID-19 tests are approved for travel purposes. That take-home test you picked up from the drugstore when you woke up with a sore throat? It can’t be used to fly back into the U.S. from abroad.
COVID-19 Test Us
Help us find new tests to stop the spread of Covid-19!
GoodRx
Coronavirus testing can be used to help understand if you have, or may have had, COVID-19. Patients who experienced symptoms of COVID-19 or believe they were exposed can consider two types of tests: antibody and active infection tests.
BinaxNOW
We're pairing this $5, 15-minute, easy-to-use test with a mobile app, called NAVICA™, which works like a secure digital "boarding pass" that can be scanned to enter organizations and other places where people gather. This combination is life-changing technology that will attack the pandemic on critical fronts – speed, simplicity, affordability, access and reliability.
BioFire
BioFire Diagnostics provides molecular diagnostic solutions to help make the world a healthier & safer place.
Cepheid
Cepheid has developed an automated molecular test for the qualitative detection of SARS-CoV-2, the virus that causes COVID-19. The test leverages the design principles of our current Xpert® Xpress Flu/RSV cartridge technology, in which multiple regions of the viral genome are targeted. The test can provide rapid detection of the current pandemic coronavirus SARS-CoV-2 in as soon as 30 minutes for positive results* with less than a minute of hands on time to prepare the sample.
Everlywell
Everlywell makes lab testing easy and convenient with at-home collection and digital results in days.
ID NOW
ID NOW™ is a leading molecular point-of-care platform in the United States, trusted by hospitals, physician offices, and urgent care clinics nationwide.
SalivaDirect
All you have to do to find out if you have COVID-19 is to send us your spit. We'll do the rest.
CDC
This document is intended to provide guidance on the categories of viral testing and intended uses of testing for SARS-CoV-2 in light of additional testing capacity throughout the country...
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