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Group testing for coronavirus – called pooled testing – could be the fastest and cheapest way to increase screening nationwide

Group testing for coronavirus – called pooled testing – could be the fastest and cheapest way to increase screening nationwide

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Pooling samples means one test can screen multiple people. Tetra Images via Getty Images

Hopes for a summertime reprieve from COVID-19 have been dashed as cases surged in June. As infections rise, so does the need for testing.

Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, recently announced that health officials are considering pooled testing for COVID-19 in response to the recent surge.

So what is pooled testing, and why does the U.S. need it?

Test groups, not individuals

The basic idea of pooled testing is that it allows public health officials to test small groups – called pools – of people using only one test. This means you can test more people faster, using fewer tests and for less money.

Instead of testing one person at a time, samples from multiple individuals would be mixed together and tested as one. If the test comes back negative, everyone in the pool is clear. If positive, each member of the pool is then tested individually.

For example, imagine a workplace with 20 people, one of whom is infected. Pooled testing divides the 20 people into four groups of five. Samples are taken from each person and mixed with the samples from other people in their group. Each grouped sample is then tested – four tests in all.

One of the pools will turn up positive because it contains the single infected person. All five people in this pool are then retested individually, and the one sick person is identified.

In all, nine tests are used and all 20 workers have been screened. If everyone had been screened individually, it would have taken 20 tests.

In practice, the number of tests saved by pooling varies depends on the fraction of people infected. Higher infection rates mean that more pools come back positive, more people need to be retested, and savings from pooling are lower.

For example, pooled testing on suspected COVID-19 cases in Los Angeles – where as of June 27 nearly 9% of people tested are positive – would reduce test use by about 50%. But in Montana, where only 0.1% of the population is infected, a pooled testing effort to test the whole state would reduce test use by nearly 90%.

No matter the exact amount, at a cost of about US$100 per test, the savings add up.

For pooled testing, individual samples are collected, then multiple samples are mixed together and screened using a PCR test that looks for bits of viral RNA. AP Photo/David Zalubowski

Does it work?

Pooled testing has long been used to test large asymptomatic populations for disease. State labs have used it to screen for chlamydia and gonorrhea and the Red Cross has used it to test donated blood for Hepatitis B and C, Zika virus and HIV.

And some places have already begun using pooled testing to screen for active coronavirus infections.

[The Conversation’s newsletter explains what’s going on with the coronavirus pandemic. Subscribe now.]

Stanford University used pooled testing to monitor the early spread of COVID-19 in the Bay Area. Nebraska’s Public Health Laboratory pooled and tested samples from five-person groups and roughly doubled the number of suspected COVID-19 patients it could test weekly.

Some people have expressed concern that the dilution of samples from pooling could reduce the accuracy of the PCR tests that look for viral RNA in samples. Fortunately, researchers have already shown that pooled testing is about as accurate as individual testing in pools as large as eight people.

Another concern is infection prevalence. When infection rates climb higher than 15%, too many pools come back positive and pooling is no longer more efficient. Fortunately, on a nationwide basis only about 5% of tests on suspected cases are coming back positive. Even in extreme hot spots like Texas, where 10% or more of suspected cases are testing positive, pooled testing could still be useful.

But the real strength of pooled testing would be seen if health officials start implementing large-scale testing of the general population.

For the most part, patients are currently tested only when a health care provider suspects they might be infected with SARS-CoV-2. However, asymptomatic and presymptomatic COVID-19 patients are common and are likely a major source of COVID-19 transmission. For this reason, experts have recommended screening everyone for infections.

In the general population, the prevalence of new infections is estimated to be less than 2%, even in the hardest-hit states. At these rates, pooled testing could reduce test costs by 80% or more.

Research has shown pooled testing to be accurate for pools up to eight samples, but labs need to get certified to do pooled testing before this approach could be widely adopted. AP Photo/John Minchillo

What to do next?

To date, the U.S. has conducted around 30 million COVID-19 tests, covering a bit less than 10% of its population. Yet, some experts have called for testing America’s entire population every three months or even every two weeks.

Considering that American labs are already short of testing reagents, it seems doubtful companies could soon produce enough material to run this many individual tests – assuming companies or governments could even pay for them all. Widespread use of pooled testing can help screen more people using fewer laboratory tests.

In order to increase capacity, the FDA recently released guidance that lays out a path to pooled testing authorization so more labs and test manufacturers can start doing it.

Another potential obstacle is cost. If labs charge much more for testing a pooled sample than they do for an individual one, any cost savings will dissipate.

Cheaper, faster testing methods enable screening that is more widespread and more frequent. Frequency is critical for monitoring a disease that spreads rapidly. Moreover, repeat testing helps pick up cases that might have been missed previously. Retesting helps, because research suggests that PCR tests miss about 20% of infected cases, no matter whether they are pooled or not.

Pooling could get the U.S. one step closer to the goal of universal and repeated testing – and play a crucial role in containing the spread of this relentless disease.

Darius Lakdawalla owns shares in Precision Medicine Group, a privately held company that provides consulting services to life sciences firms, including those that produce COVID-19 tests.

Erin Trish is the associate director of the USC Schaeffer Center for Health Policy and Economics and a non-resident fellow in Economic Studies at the Brookings Institution.

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Analyst reviews Apple stock price target amid challenges

Here’s what could happen to Apple shares next.

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7 hours ago

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March 12, 2024

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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

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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…

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March 12, 2024

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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

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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…

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March 12, 2024

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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

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