Connect with us

Government

Rapid tests play a crucial role in curbing COVID-19 infections – especially as people gather for the holidays

Knowing when and how often to use rapid tests is key to getting an accurate picture of your COVID-19 status.

Published

2 years ago

on

The key to rapid antigen testing is to test early in the course of COVID-19 infection, ideally several times 24 hours apart. VioletaStoimenova/E+ via Getty Images

As winter begins and the holidays are in full swing, the COVID-19 pandemic has entered another worrying phase. Emergence of the omicron variant, along with increasing rates of infections, have left many people unsure about their holiday plans.

On Dec. 2, 2021, President Joe Biden outlined a series of actions to respond to the COVID-19 pandemic, including making at-home COVID-19 rapid tests eligible for reimbursement by private insurance. Along with vaccination, testing remains one of the most effective ways to track and reduce transmission of SARS-CoV-2, the virus that causes COVID-19.

Even though COVID-19 testing has become part of most people’s everyday conversation, many people still have questions about the difference between antigen and PCR tests, including when and how to use them.

I’m a molecular biologist based at UMass Chan Medical School. Since April 2020, I’ve been part of a team working on a National Institutes of Health-funded program called RADx Tech to help companies develop rapid tests to detect when a person is infected with COVID-19.

How rapid antigen tests work

Rapid antigen tests are designed to detect a portion of protein – known as an antigen – of SARS-CoV-2. First, you take a sample from your nose or mouth with a swab, as directed. You mix the sample with liquid that breaks apart the virus. You then apply the liquid to a test strip that has antibodies specific for SARS-CoV-2 painted on it in a thin line. Antibodies are Y-shaped proteins that recognize and bind to foreign substances such as antigens. If the antibodies bind to the virus proteins, or antigens, a colored line appears on the test strip, indicating the presence of SARS-CoV-2.

These tests are convenient because they are easy to use and provide results quickly, typically within about 15 minutes. Another benefit is that antigen tests can be relatively inexpensive, at around US$10-$15 per test. In contrast, PCR tests usually require laboratory equipment and technicians, take 12 hours to several days to get results and cost $100 or more, though there are many ways to get these tests free of charge.

In his announcement, President Biden also discussed plans to distribute 50 million free tests to community health care providers for people without insurance. People should check their local media outlets for information about when free rapid tests become available. In Colorado, free rapid tests have been available to families with school-age children for months. Be prepared to act quickly: In late November, 100,000 people signed up in less than 24 hours for free antigen COVID tests in New Hampshire.

People embrace next to a free COVID-19 rapid testing sign at Los Angeles International Airport.
Los Angeles International Airport is offering free rapid COVID-19 tests to incoming international travelers. Mario Tama/Getty Images News via Getty Images

As of early December 2021, the Food and Drug Administration has authorized about a dozen rapid antigen tests for SARS-CoV-2, which means these tests meet certain standards for performance and accuracy.

When to use rapid tests

If you have any symptoms of COVID-19, regardless of whether you’ve been vaccinated, you should get tested right away with either a PCR or antigen test.

SARS-CoV-2 can spread very easily, even if you don’t have symptoms. The faster you can determine if you have COVID-19, the sooner you can isolate yourself, which helps prevent transmission to others. Early testing is also critical because new drugs like those from Merck and Pfizer are most effective if given early in the course of infection, soon after symptoms appear.

If you get a negative antigen test but still feel sick, it is possible that you received a false negative test. Isolate yourself away from others and contact your health care provider to discuss your symptoms. If you get a positive test, you should isolate yourself at home and contact your health care provider as soon as possible.

If you don’t have symptoms but have had close contact with someone with COVID-19, what to do depends on your vaccine status. If you’re fully vaccinated, the CDC currently recommends that you wait five to seven days after your exposure and then get a PCR or rapid antigen test. If you’re not fully vaccinated, get tested right away. If you don’t develop symptoms, you should still get retested five to seven days after your exposure.

Like many respiratory viruses, it takes several days for SARS-CoV-2 to build up in your body after exposure. During this early phase of infection, the amount of viral protein is relatively low, and a rapid test may not detect your infection. This is why serial testing over multiple days, with at least 24 hours between each test, is recommended for many antigen tests. Rapid antigen tests are most often accurate when a person is infectious, because that is when the highest amount of virus is in the respiratory tract.

Studies have shown that serial antigen testing – typically two to three tests in one week – is on par with a single PCR test. Remember that a test is only a snapshot of your SARS-CoV-2 status at the time of the test. It’s possible, especially with antigen tests, to test negative during the early stages of infection.

The future for at-home COVID-19 testing

Despite all that we researchers have learned, there is still more to understand about the best way to use rapid tests. Our team is conducting several studies to fill these gaps.

Closeup of a COVID-19 rapid test.
The CDC recommends that fully vaccinated people wait five to seven days after a COVID-19 exposure before getting a PCR or rapid antigen test. Those not fully vaccinated should get tested right away. lupmotion/iStock/Getty Images Plus via Getty Images

One question we are studying with a program called STOP COVID-19 is how people use home tests when their infection risk is low versus high. For instance, someone who wears a mask indoors and does not eat out at restaurants may be considered low risk, while someone who is not vaccinated and gathers with many people without masks is considered high risk. We are also interested in knowing whether people will adhere to a testing regimen when they have an exposure, and whether they will share their home test results with their local department of public health.

Another major question our team is studying is: How do antigen tests compare with PCR tests when it comes to detecting COVID-19 in people who are positive but have no symptoms? A separate nationwide study called Test Us at Home is generating important data that will help us answer this question in the next few months.

Rapid antigen tests are a welcome tool in society’s fight against the COVID-19 pandemic. When used properly and in combination with other tools such as vaccination, mask-wearing and good hygiene, these actions can help limit the spread of SARS-CoV-2 this holiday season.

[Like what you’ve read? Want more? Sign up for The Conversation’s daily newsletter.]

Nathaniel Hafer receives funding from the National Institutes of Health via awards UL1TR001453 and U54HL143541.

Read More

Related Topics:
Continue Reading

International

Analyst reviews Apple stock price target amid challenges

Here’s what could happen to Apple shares next.

Published

9 hours ago

on

March 12, 2024

By

They said it was bound to happen.

It was Jan. 11, 2024 when software giant Microsoft  (MSFT)  briefly passed Apple  (AAPL)  as the most valuable company in the world.

Microsoft's stock closed 0.5% higher, giving it a market valuation of $2.859 trillion. 

It rose as much as 2% during the session and the company was briefly worth $2.903 trillion. Apple closed 0.3% lower, giving the company a market capitalization of $2.886 trillion. 

"It was inevitable that Microsoft would overtake Apple since Microsoft is growing faster and has more to benefit from the generative AI revolution," D.A. Davidson analyst Gil Luria said at the time, according to Reuters.

The two tech titans have jostled for top spot over the years and Microsoft was ahead at last check, with a market cap of $3.085 trillion, compared with Apple's value of $2.684 trillion.

Analysts noted that Apple had been dealing with weakening demand, including for the iPhone, the company’s main source of revenue. 

Demand in China, a major market, has slumped as the country's economy makes a slow recovery from the pandemic and competition from Huawei.

Sales in China of Apple's iPhone fell by 24% in the first six weeks of 2024 compared with a year earlier, according to research firm Counterpoint, as the company contended with stiff competition from a resurgent Huawei "while getting squeezed in the middle on aggressive pricing from the likes of OPPO, vivo and Xiaomi," said senior Analyst Mengmeng Zhang.

“Although the iPhone 15 is a great device, it has no significant upgrades from the previous version, so consumers feel fine holding on to the older-generation iPhones for now," he said.

A man scrolling through Netflix on an Apple iPad Pro. Photo by Phil Barker/Future Publishing via Getty Images.

Future Publishing/Getty Images

Big plans for China

Counterpoint said that the first six weeks of 2023 saw abnormally high numbers with significant unit sales being deferred from December 2022 due to production issues.

Apple is planning to open its eighth store in Shanghai – and its 47th across China – on March 21.

Related: Tech News Now: OpenAI says Musk contract 'never existed', Xiaomi's EV, and more

The company also plans to expand its research centre in Shanghai to support all of its product lines and open a new lab in southern tech hub Shenzhen later this year, according to the South China Morning Post.

Meanwhile, over in Europe, Apple announced changes to comply with the European Union's Digital Markets Act (DMA), which went into effect last week, Reuters reported on March 12.

Beginning this spring, software developers operating in Europe will be able to distribute apps to EU customers directly from their own websites instead of through the App Store.

"To reflect the DMA’s changes, users in the EU can install apps from alternative app marketplaces in iOS 17.4 and later," Apple said on its website, referring to the software platform that runs iPhones and iPads. 

"Users will be able to download an alternative marketplace app from the marketplace developer’s website," the company said.

Apple has also said it will appeal a $2 billion EU antitrust fine for thwarting competition from Spotify  (SPOT)  and other music streaming rivals via restrictions on the App Store.

The company's shares have suffered amid all this upheaval, but some analysts still see good things in Apple's future.

Bank of America Securities confirmed its positive stance on Apple, maintaining a buy rating with a steady price target of $225, according to Investing.com. 

The firm's analysis highlighted Apple's pricing strategy evolution since the introduction of the first iPhone in 2007, with initial prices set at $499 for the 4GB model and $599 for the 8GB model.

BofA said that Apple has consistently launched new iPhone models, including the Pro/Pro Max versions, to target the premium market. 

Analyst says Apple selloff 'overdone'

Concurrently, prices for previous models are typically reduced by about $100 with each new release. 

This strategy, coupled with installment plans from Apple and carriers, has contributed to the iPhone's installed base reaching a record 1.2 billion in 2023, the firm said.

More Tech Stocks:

Apple has effectively shifted its sales mix toward higher-value units despite experiencing slower unit sales, BofA said.

This trend is expected to persist and could help mitigate potential unit sales weaknesses, particularly in China. 

BofA also noted Apple's dominance in the high-end market, maintaining a market share of over 90% in the $1,000 and above price band for the past three years.

The firm also cited the anticipation of a multi-year iPhone cycle propelled by next-generation AI technology, robust services growth, and the potential for margin expansion.

On Monday, Evercore ISI analysts said they believed that the sell-off in the iPhone maker’s shares may be “overdone.”

The firm said that investors' growing preference for AI-focused stocks like Nvidia  (NVDA)  has led to a reallocation of funds away from Apple. 

In addition, Evercore said concerns over weakening demand in China, where Apple may be losing market share in the smartphone segment, have affected investor sentiment.

And then ongoing regulatory issues continue to have an impact on investor confidence in the world's second-biggest company.

“We think the sell-off is rather overdone, while we suspect there is strong valuation support at current levels to down 10%, there are three distinct drivers that could unlock upside on the stock from here – a) Cap allocation, b) AI inferencing, and c) Risk-off/defensive shift," the firm said in a research note.

Related: Veteran fund manager picks favorite stocks for 2024

Read More

Continue Reading

International

Major typhoid fever surveillance study in sub-Saharan Africa indicates need for the introduction of typhoid conjugate vaccines in endemic countries

There is a high burden of typhoid fever in sub-Saharan African countries, according to a new study published today in The Lancet Global Health. This high…

Published

9 hours ago

on

March 12, 2024

By

There is a high burden of typhoid fever in sub-Saharan African countries, according to a new study published today in The Lancet Global Health. This high burden combined with the threat of typhoid strains resistant to antibiotic treatment calls for stronger prevention strategies, including the use and implementation of typhoid conjugate vaccines (TCVs) in endemic settings along with improvements in access to safe water, sanitation, and hygiene.

Credit: IVI

There is a high burden of typhoid fever in sub-Saharan African countries, according to a new study published today in The Lancet Global Health. This high burden combined with the threat of typhoid strains resistant to antibiotic treatment calls for stronger prevention strategies, including the use and implementation of typhoid conjugate vaccines (TCVs) in endemic settings along with improvements in access to safe water, sanitation, and hygiene.

 

The findings from this 4-year study, the Severe Typhoid in Africa (SETA) program, offers new typhoid fever burden estimates from six countries: Burkina Faso, Democratic Republic of the Congo (DRC), Ethiopia, Ghana, Madagascar, and Nigeria, with four countries recording more than 100 cases for every 100,000 person-years of observation, which is considered a high burden. The highest incidence of typhoid was found in DRC with 315 cases per 100,000 people while children between 2-14 years of age were shown to be at highest risk across all 25 study sites.

 

There are an estimated 12.5 to 16.3 million cases of typhoid every year with 140,000 deaths. However, with generic symptoms such as fever, fatigue, and abdominal pain, and the need for blood culture sampling to make a definitive diagnosis, it is difficult for governments to capture the true burden of typhoid in their countries.

 

“Our goal through SETA was to address these gaps in typhoid disease burden data,” said lead author Dr. Florian Marks, Deputy Director General of the International Vaccine Institute (IVI). “Our estimates indicate that introduction of TCV in endemic settings would go to lengths in protecting communities, especially school-aged children, against this potentially deadly—but preventable—disease.”

 

In addition to disease incidence, this study also showed that the emergence of antimicrobial resistance (AMR) in Salmonella Typhi, the bacteria that causes typhoid fever, has led to more reliance beyond the traditional first line of antibiotic treatment. If left untreated, severe cases of the disease can lead to intestinal perforation and even death. This suggests that prevention through vaccination may play a critical role in not only protecting against typhoid fever but reducing the spread of drug-resistant strains of the bacteria.

 

There are two TCVs prequalified by the World Health Organization (WHO) and available through Gavi, the Vaccine Alliance. In February 2024, IVI and SK bioscience announced that a third TCV, SKYTyphoid™, also achieved WHO PQ, paving the way for public procurement and increasing the global supply.

 

Alongside the SETA disease burden study, IVI has been working with colleagues in three African countries to show the real-world impact of TCV vaccination. These studies include a cluster-randomized trial in Agogo, Ghana and two effectiveness studies following mass vaccination in Kisantu, DRC and Imerintsiatosika, Madagascar.

 

Dr. Birkneh Tilahun Tadesse, Associate Director General at IVI and Head of the Real-World Evidence Department, explains, “Through these vaccine effectiveness studies, we aim to show the full public health value of TCV in settings that are directly impacted by a high burden of typhoid fever.” He adds, “Our final objective of course is to eliminate typhoid or to at least reduce the burden to low incidence levels, and that’s what we are attempting in Fiji with an island-wide vaccination campaign.”

 

As more countries in typhoid endemic countries, namely in sub-Saharan Africa and South Asia, consider TCV in national immunization programs, these data will help inform evidence-based policy decisions around typhoid prevention and control.

 

###

 

About the International Vaccine Institute (IVI)
The International Vaccine Institute (IVI) is a non-profit international organization established in 1997 at the initiative of the United Nations Development Programme with a mission to discover, develop, and deliver safe, effective, and affordable vaccines for global health.

IVI’s current portfolio includes vaccines at all stages of pre-clinical and clinical development for infectious diseases that disproportionately affect low- and middle-income countries, such as cholera, typhoid, chikungunya, shigella, salmonella, schistosomiasis, hepatitis E, HPV, COVID-19, and more. IVI developed the world’s first low-cost oral cholera vaccine, pre-qualified by the World Health Organization (WHO) and developed a new-generation typhoid conjugate vaccine that is recently pre-qualified by WHO.

IVI is headquartered in Seoul, Republic of Korea with a Europe Regional Office in Sweden, a Country Office in Austria, and Collaborating Centers in Ghana, Ethiopia, and Madagascar. 39 countries and the WHO are members of IVI, and the governments of the Republic of Korea, Sweden, India, Finland, and Thailand provide state funding. For more information, please visit https://www.ivi.int.

 

CONTACT

Aerie Em, Global Communications & Advocacy Manager
+82 2 881 1386 | aerie.em@ivi.int

Journal

The Lancet Global Health

Method of Research

Observational study

Subject of Research

People

Article Title

Incidence of typhoid fever in Burkina Faso, Democratic Republic of the Congo, Ethiopia, Ghana, Madagascar, and Nigeria (the Severe Typhoid in Africa programme): a population-based study

Article Publication Date

12-Mar-2024

Read More

Continue Reading

International

US Spent More Than Double What It Collected In February, As 2024 Deficit Is Second Highest Ever… And Debt Explodes

US Spent More Than Double What It Collected In February, As 2024 Deficit Is Second Highest Ever… And Debt Explodes

Earlier today, CNBC’s…

Published

11 hours ago

on

March 12, 2024

By

US Spent More Than Double What It Collected In February, As 2024 Deficit Is Second Highest Ever... And Debt Explodes

Earlier today, CNBC's Brian Sullivan took a horse dose of Red Pills when, about six months after our readers, he learned that the US is issuing $1 trillion in debt every 100 days, which prompted him to rage tweet, (or rageX, not sure what the proper term is here) the following:

We’ve added 60% to national debt since 2018. Germany - a country with major economic woes - added ‘just’ 32%.   

Maybe it will never matter.   Maybe MMT is real.   Maybe we just cancel or inflate it out. Maybe career real estate borrowers or career politicians aren’t the answer.

I have no idea.  Only time will tell.   But it’s going to be fascinating to watch it play out.

He is right: it will be fascinating, and the latest budget deficit data simply confirmed that the day of reckoning will come very soon, certainly sooner than the two years that One River's Eric Peters predicted this weekend for the coming "US debt sustainability crisis."

According to the US Treasury, in February, the US collected $271 billion in various tax receipts, and spent $567 billion, more than double what it collected.

The two charts below show the divergence in US tax receipts which have flatlined (on a trailing 6M basis) since the covid pandemic in 2020 (with occasional stimmy-driven surges)...

... and spending which is about 50% higher compared to where it was in 2020.

The end result is that in February, the budget deficit rose to $296.3 billion, up 12.9% from a year prior, and the second highest February deficit on record.

And the punchline: on a cumulative basis, the budget deficit in fiscal 2024 which began on October 1, 2023 is now $828 billion, the second largest cumulative deficit through February on record, surpassed only by the peak covid year of 2021.

But wait there's more: because in a world where the US is spending more than twice what it is collecting, the endgame is clear: debt collapse, and while it won't be tomorrow, or the week after, it is coming... and it's also why the US is now selling $1 trillion in debt every 100 days just to keep operating (and absorbing all those millions of illegal immigrants who will keep voting democrat to preserve the socialist system of the US, so beloved by the Soros clan).

And it gets even worse, because we are now in the ponzi finance stage of the Minsky cycle, with total interest on the debt annualizing well above $1 trillion, and rising every day

... having already surpassed total US defense spending and soon to surpass total health spending and, finally all social security spending, the largest spending category of all, which means that US debt will now rise exponentially higher until the inevitable moment when the US dollar loses its reserve status and it all comes crashing down.

We conclude with another observation by CNBC's Brian Sullivan, who quotes an email by a DC strategist...

.. which lays out the proposed Biden budget as follows:

The budget deficit will growth another $16 TRILLION over next 10 years. Thats *with* the proposed massive tax hikes.

Without them the deficit will grow $19 trillion.

That's why you will hear the "deficit is being reduced by $3 trillion" over the decade.

No family budget or business could exist with this kind of math.

Of course, in the long run, neither can the US... and since neither party will ever cut the spending which everyone by now is so addicted to, the best anyone can do is start planning for the endgame.

Tyler Durden Tue, 03/12/2024 - 18:40

Read More

Continue Reading

Trending