Rechercher dans ce blog

Sunday, August 30, 2020

No easy answers on testing for virus - Arkansas Online

As a new school year dawns, the demand for cheaper, faster and more accessible coronavirus testing is growing. But slow and sometimes erroneous test results and confusion over when and how to get tested continue to plague Americans as they wrestle with decisions about resuming their lives.

Meanwhile, some of the nation's leading public health experts are raising a new concern in the endless debate over testing in the United States: The standard tests are diagnosing huge numbers of people who may be carrying relatively insignificant amounts of the virus.

[Video not showing up above? Click here to view » https://www.youtube.com/watch?v=zlO86YMGg88]

Most of these people are not likely to be contagious, and identifying them may contribute to bottlenecks that prevent those who are contagious from being found in time. But researchers say the solution is not to test less, or to skip testing people without symptoms, as recently suggested by the Centers for Disease Control and Prevention.

Instead, new data underscore the need for more widespread use of rapid tests, even if they are less sensitive.

"The decision not to test asymptomatic people is just really backward," said Dr. Michael Mina, an epidemiologist at the Harvard T.H. Chan School of Public Health, referring to the CDC recommendation.

"In fact, we should be ramping up testing of all different people," he said, "but we have to do it through whole different mechanisms."

In what may be a step in this direction, the Trump administration announced Thursday that it would purchase 150 million rapid tests.

"I started to talk to colleagues nationally, and I was taken aback that most [public school] districts and most charter networks really had thrown in the towel quickly and said testing was too expensive and too complicated," said Laura Clancy, chief talent officer for a nonprofit charter school network in Philadelphia and Camden, N.J., that plans to open its 24 schools on a limited basis by Oct. 1 pending community transmission rates and local guidance.

Some universities are already closing their campuses because they can't keep up with outbreaks. A growing chorus of scientists say occasional screening, or surveillance, is not enough; they say students and others need to be able to screen themselves at least twice a week.

Testing companies and policy advocates face regulatory, scientific, logistical and ethical hurdles more than half a year after the virus appeared in the United States.

Gallery: President Trump visits Louisiana and Texas

[Gallery not loading above? Click here for more photos » arkansasonline.com/830covid/]

Turnaround times for most tests have improved in recent weeks, in part because of a substantial drop in the number of tests administered. Still, the Trump administration estimates that over the past month, 1 in 5 tests took more than three days to come back -- rendering results largely useless. The equipment needed at the nation's biggest private lab companies is expensive and on back order.

Many companies have developed faster, cheaper tests, but there is a trade-off: Such tests are not nearly as sensitive as the standard coronavirus tests that can take days or weeks to process. The Food and Drug Administration is opposed to letting people take these tests at home, fearing it would create a false sense of security. And public health experts remain deeply divided.

Testing serves two purposes. One is diagnostic, in which it is used to confirm the presence of the virus in people who have symptoms or a known exposure to someone who is already sick. The other is to detect people who are infected but don't know it. That second purpose is especially important for screening asymptomatic people out of large groups, at schools and elsewhere.

[CORONAVIRUS: Click here for our complete coverage » arkansasonline.com/coronavirus]

TESTS' ROLE DEBATED

There are two kinds of tests to look for active infections. Molecular tests search for the virus's genetic material. Antigen tests look for spiky proteins on the surface of the virus.

The gold-standard test is molecular -- a polymerase chain reaction or PCR test performed with a long nasal swab, known to be highly sensitive because of an expensive and time-consuming amplification process that finds even a small bit of infectious material.

Antigen tests are simpler and cheaper but less sensitive; they need more virus in the body to generate a positive result.

The new rapid tests that the White House is seeking do yield results in 15 minutes without added equipment, but they still must be analyzed by a medical professional. Technically they are approved for use only on people with symptoms, although the White House is touting them as a potential solution for schools and businesses.

[EMAIL SIGNUP: Form not appearing above? Click here to subscribe to updates on the coronavirus » arkansasonline.com/coronavirus/email/]

Some experts argue that the only way out of the morass is testing that is even cheaper and simpler, performed entirely at home -- even if it is not as sensitive.

"This can work better than a vaccine if it could just be produced at scale," said epidemiologist Mina, who has become a vocal advocate for rapid at-home testing. The tests "are not going to tell you if you definitely do or do not have any virus in you. And that's not their role. They're going to tell you if on a given day when you wake up and use this test inside of your house, you are at risk of transmitting the virus to other people."

The novel coronavirus is particularly difficult to contain because it has a long incubation period and often leaves no symptoms behind. A test could be taken too early to catch the virus, or the results could come too late, when a person is already infecting others.

That's why some public health experts argue in favor of rapid tests: If they're cheap and convenient enough, they could be taken repeatedly by the same person, something unlikely to happen with more expensive PCR testing.

While the rapid tests might not catch every infection, experts say they should detect the most contagious cases.

HOSPITAL STAFFING AT ISSUE

Separately, nurses on the front lines of New York's covid-19 pandemic are calling for the state to enact minimum staffing standards ahead of another wave of infections.

Health care industry leaders, though, warn that passing such a law would saddle facilities with billions of dollars in extra costs that they can't afford.

Under legislation now before a legislative committee, the state would for the first time set minimum nurse-to-patient ratios, including a standard of one nurse for every two patients in intensive care.

California now has such a law. Other states don't. Supporters say the legislation would boost the quality of care, reduce staff burnout and let the state hold health care facilities accountable for inadequate staffing.

Minimum staffing ratios also might have helped last spring, they say, when hospitals and nursing homes in the New York City metropolitan area were overwhelmed with a flood of covid-19 patients.

"If we had better staffing in place before covid-19, if we weren't stretched so thin, we would have been able to handle the flex and surge that was required," said Pat Kane, who leads a union representing nurses statewide.

Health industry groups have long called minimum staffing levels too costly and unnecessary. They say implementing staffing mandates now would be especially damaging as hospitals face sharp revenue losses.

New York Gov. Andrew Cuomo promised in 2018 to set safe staffing levels, which he said was "linked to quality care," but this month his health department released a report estimating the proposed staffing rules would force nursing homes and hospitals to hire a combined 35,000 nurses, at a cost of about $4 billion.

"During the crisis, the increased costs would have been unbearable, coming on top of the extremely expensive surge costs frontline hospitals incurred," Greater New York Hospital Association President Kenneth Raske told hospital leaders this month. "Now, in the covid-19 transition era, when hospitals are fighting for their very survival due to a severe loss of revenue, such a mandate is unthinkable."

It also is not clear whether staffing mandates would have made any difference in an extraordinary crisis like the one that enveloped the health care system last spring, when hospitals were seeing so many dying patients that they had to bring in refrigerator trucks to handle the bodies.

Simultaneously, many health care workers themselves were falling ill, disrupting regular staffing plans. With help from the state and staffing agencies, hospitals brought in thousands of temporary staff, often people from other states, but it took weeks for the help to arrive.

UNREST IN BERLIN

Elsewhere, far-right extremists tried to storm the German parliament building Saturday after a protest against the country's pandemic restrictions, but were intercepted by police and forcibly removed.

The incident occurred after a daylong demonstration by tens of thousands of people opposed to the wearing of masks and other government measures intended to stop the spread of the virus.

Police ordered the protesters to disband halfway through their march around Berlin after participants refused to observe social distancing rules, but a rally near the capital's iconic Brandenburg Gate took place as planned.

Footage of the incident showed hundreds of people, some waving the flag of the German Reich of 1871-1918 and other far-right banners, running toward the Reichstag building and up the stairs.

Police confirmed on Twitter that several people had broken through a cordon in front of Parliament and "entered the staircase of the Reichstag building, but not the building itself."

"Stones and bottles were thrown at our colleagues," police said. "Force had to be used to push them back."

Germany's top security official condemned the incident.

"The Reichstag building is the workplace of our Parliament and therefore the symbolic center of our liberal democracy," Interior Minister Horst Seehofer said in a statement.

"It's unbearable that vandals and extremists should misuse it," he said, calling on authorities to show "zero tolerance."

NO SINGLE ISSUE

Earlier, thousands of far-right extremists had thrown bottles and stones at police outside the Russian Embassy. Police detained about 300 people throughout the day.

During the march, which authorities said drew about 38,000 people, participants expressed their opposition to a wide range of issues, including vaccinations, masks and the German government in general. Some wore T-shirts promoting the "QAnon" conspiracy theory while others displayed white nationalist slogans and neo-Nazi insignia, though most participants denied having far-right views.

Uwe Bachmann, 57, said he had come from southwestern Germany to protest for free speech and his right not to wear a mask.

"I respect those who are afraid of the virus," said Bachmann.

Meanwhile, a few hundred people rallied Saturday in eastern Paris to protest new mask rules and other restrictions prompted by rising virus infections around France. Police watched closely but did not intervene.

The protesters had no central organizer but included people in yellow vests who formerly protested economic injustice, others promoting conspiracy theories and those who call themselves "Anti-Masks."

France has not seen an anti-mask movement like some other countries. Masks are now required everywhere in public in Paris as authorities warn that infections are growing exponentially just as schools are set to resume classes.

Information for this article was contributed by Rachel Weiner, Steven Mufson and Laurie McGinley of The Washington Post; by Apoorva Mandavilli of The New York Times; and by Marina Villeneuve, Frank Jordans, Angela Charlton and Silvia Hui of The Associated Press.

A technician loads saliva tests at the Waksman Institute of Microbiology. MUST CREDIT: photo for The Washington Post by Bryan Anselm.
A technician loads saliva tests at the Waksman Institute of Microbiology. MUST CREDIT: photo for The Washington Post by Bryan Anselm.
Technicians process coronavirus saliva tests at the Waksman Institute of Microbiology in Piscataway, N.J. MUST CREDIT: photo for The Washington Post by Bryan Anselm.
Technicians process coronavirus saliva tests at the Waksman Institute of Microbiology in Piscataway, N.J. MUST CREDIT: photo for The Washington Post by Bryan Anselm.
Photo by AP
A girl holds her doll as she attends a mourning ceremony Saturday in Tehran, Iran, to commemorate the seventh-century death of Proph- et Muhammad’s grandson Hussein, one of Shiite Islam’s most be- loved saints. People attending the ceremony were required to wear masks, socially distance, use sanitizers and have their temperatures checked. More photos at arkansasonline.com/830covid/. (AP/Vahid Salemi)

Let's block ads! (Why?)



"virus" - Google News
August 30, 2020 at 04:33PM
https://ift.tt/3hG2YX2

No easy answers on testing for virus - Arkansas Online
"virus" - Google News
https://ift.tt/2OagXru

No comments:

Post a Comment

Featured Post

Measles is “growing global threat,” CDC tells doctors in alert message - Ars Technica

Enlarge / A baby with measles. CDC The Centers for Disease Control and Prevention is putting clinicians on alert about the growing r...

Popular Posts