Category: Public Health

By Julie Appleby and Phil Galewitz

Published by KHN on January 13, 2022. Read the original version here.

Julie Ann Justo, an infectious disease clinical pharmacist for a South Carolina hospital system, hoped Christmas week would finally be the time her family could safely gather for a reunion.

Before the celebration, family members who were eligible were vaccinated and boosted. They quarantined and used masks in the days leading up to the event. And many took solace in negative results from rapid covid-19 tests taken a few days before the 35-person indoor gathering in South Florida to make sure no one was infectious.

But within a week, Justo and at least 13 members of her extended family tested positive for covid, with many feeling typical symptoms of an upper respiratory virus, such as a sore throat and a runny nose.

Like many other Americans, Justo’s family learned the hard way that a single negative result from an at-home rapid test, which takes about 15 minutes, is no guarantee that a person is not ill or carrying the virus.

There are just so many variables. Testing may come either too soon, before enough virus is present to detect, or too late, after a person has already spread the virus to others.

And most rapid tests, even according to their instructions, are meant to be used in pairs — generally a day or two apart — for increased accuracy. Despite that, a few brands are sold one to a box and, with the tests sometimes expensive and in short supply, families are often relying on a single screening.

While home antigen testing remains a useful — and underutilized — tool to curb the pandemic, experts say, it is often misused and may provide false confidence.

Some people mistakenly look at the home tests “like a get-out-of-jail-free card,” said Dr. William Schaffner, a specialist in infectious diseases at the Vanderbilt University School of Medicine in Nashville, Tennessee. “‘I’m negative, so I don’t have to worry anymore.’”

That is even more true now that the new more transmissible variant dominates the country.

“Omicron is so transmissible that it is challenging to use any kind of testing strategy in terms of get-togethers and be successful,” said Dr. Patrick Mathias, vice chair of clinical operations for the Department of Laboratory Medicine & Pathology at the University of Washington School of Medicine.

Rapid tests are pretty good at correctly detecting infection in people with symptoms, Mathias said, with a 70% to nearly 90% range of accuracy estimated in several studies. Other studies, some that predate current variants or were performed under more controlled settings, have shown higher rates, but, even then, the tests can still miss some infected people. That raises the risk of spread, with the chance rising dramatically as the number of people attending an event grows.

Results of antigen tests are less accurate for people without symptoms.

For the asymptomatic, the rapid tests, “on average, [correctly] detect infection roughly 50% of the time,” said Shama Cash-Goldwasser, an adviser for Prevent Epidemics at Resolve to Save Lives, a nonprofit group run by Dr. Tom Frieden, a former director of the Centers for Disease Control and Prevention.

Looking back, Justo said her family took precautions, but she acknowledges missteps that put them at increased risk: Not all family members were tested before getting together because of a shortage of test kits. Some members of her family who could find rapid tests tested just once because of the need to ration tests. And in attendance were several children under age 5 who are not yet eligible for a covid vaccine. They were later among the first to show symptoms.

“We probably were relying too heavily on negative rapid tests in order to gather indoors with others without other layers of protections,” she said.

Even if everyone tested properly before the party, health experts said, it wouldn’t mean all attendees are “safe” from getting covid. Testing merely reduces the risk of exposure; it doesn’t eliminate it.

Other factors in assessing risk at a gathering: Is everyone vaccinated and boosted, which can help reduce the likelihood of infection? Did attendees properly follow all the steps outlined in the test kits’ instructions, which can differ by brand? Did anyone test too early after exposure or, conversely, not close enough to the event?

One critical detail “is the timing of the test,” said Schaffner at Vanderbilt. Another, he said, is how well the tests can spot true positives and true negatives.

Test too early, such as within a day or two of exposure, and results won’t be accurate. Similarly, testing several days before an event won’t tell you much about who might be infectious on the day of the gathering.

Schaffner and others recommend that self-testing start three days after a known exposure or, if one feels ill, a few days after the onset of symptoms. Because the timeline for detecting an infection is uncertain, it’s always a good idea to use both tests in the kit, as instructed — the second one 24 to 36 hours after the first. For an event, make sure one of the tests is performed on the day of the gathering.

Antigen tests work by looking for proteins from the surface of the virus, which must be present in adequate amounts for a test to spot. (Lab-based PCR tests, or polymerase chain reaction tests, are more accurate because they can detect smaller amounts of the virus, but they take longer to get results, possibly even days, depending on the backlog at the labs.)

Covid markers may linger as remnants long after live virus is gone, so some scientists question the use of tests — whether antigen or PCR — as a metric for when patients can end their isolation, particularly if they are looking to shorten the recommended period. The CDC recommends five days of isolation, which can end if their symptoms are gone or resolving, with no fever.

Some patients will test positive 10 days or more after their first symptoms, although it is unlikely they remain infectious by then.

Still, that means many people are using the rapid tests inappropriately — not only over-relying on them as a safeguard against covid, but also as a gauge for when an infection is over.

Rapid home tests need to be used over multiple days to increase the chance of an accurate result.

“Each individual test does not have much value as serial testing,” said Dr. Zishan Siddiqui, chief medical officer at the Baltimore Convention Center Field Hospital and an assistant professor of medicine at Johns Hopkins University. And, because the tests are less reliable in those without symptoms, he said, asymptomatic people should not be relying on a single rapid test to gather with friends or family without taking other mitigation measures.

Worse still, a recent study looking at the omicron variant found that rapid tests could not detect the virus in the first two days of infection, even though lab-based PCR tests did find evidence of covid.

The study examined 30 vaccinated adults in December 2021. “Most omicron cases were infectious for several days before being detectable by rapid antigen tests,” according to the study, which has not been peer-reviewed.

False negatives are also more likely when the extent of the disease in a certain area, called community spread, is rampant, which is true for most of the United States today.

“If there’s a lot of community spread, that increases the likelihood that you have covid” at a gathering, explained Cash-Goldwasser, since one or more attendees who tested negative may have received a false result. Positivity rates are running over 25% now in some U.S. cities, indicating a lot of virus is circulating.

So, right now, “if you get a negative result, it’s important to be more suspicious,” she said.

Vaccinations, boosters, masking, physical distancing, ventilation and testing separately are all imperfect strategies to prevent infection. But layered together, they can serve as a more effective barrier, Schaffner said.

“The rapid test is useful” — his own family used them before gathering for Thanksgiving and Christmas — “but it’s a barrier with holes in it,” he added.

The virus moved through those gaps to crash the party and infect the Justo family. While most of the attendees largely had mild symptoms, Justo said she was short of breath, fatigued and experienced headaches, muscle pain and nausea. It took about 10 days before she felt better.

“I certainly spent a lot of time going back to what we could have done differently,” Justo said. “Thankfully no one needed to go to the hospital, and I attribute that to the vaccinations — and for that I am grateful.”

By Jason Terk, MD

Published by KevinMD.com on October 20, 2021. You can read the original article here.

In March 1630, John Winthrop delivered the treatise “A Model of Christian Charity” at Holyrood Church in Southampton, England, prior to leading the first settlers of the Massachusetts Bay colony on their to journey to the New World. In his address, he referred to the new community they would found as a city upon a hill with the eyes of all people upon them. This reference to a portion of Jesus’ Sermon on the Mount underscored the importance of committing the colonists to brotherly love and unity, setting the needs of others and the community above one’s own needs.

I first heard this reference to a shining city on a hill at the moment of my political awakening and at the close of Ronald Reagan’s presidency in his farewell address in January 1989:

I’ve spoken of the shining city all my political life, but I don’t know if I ever quite communicated what I saw when I said it. But in my mind, it was a tall, proud city built on rocks stronger than oceans, wind-swept, God-blessed, and teeming with people of all kinds living in harmony and peace; a city with free ports that hummed with commerce and creativity. And if there had to be city walls, the walls had doors, and the doors were open to anyone with the will and the heart to get here. That’s how I saw it and see it still.

I was never much a fan of Reagan but did recognize his desire to lead all of us as a nation of different people who had unique talents to share and whose commonality of purpose exceeded partisan divisions. I also recognized that this vision was as aspirational as the source that inspired it. North stars have their role if only we faithfully chart our course by them.

As Reagan’s farewell words washed over me, I looked ahead at my immediate future and recalled my recent past. I would graduate from college a few months later and start medical school. I had just completed an idyllic nine months of study in Hamilton, New Zealand, an experience that still influences me today. I witnessed a nation of diverse people that cared about each other meaningfully. The Kiwi culture is exemplified in their national sport, rugby, emphasizing the team over the individual.

That promise of the shining city seemed more tangible as we witnessed the close of the 1980s and experienced the bliss of the 1990s. I and my contemporaries moved through those years, getting married, starting families, starting jobs, and acquiring mortgages. The demons of our nation still seemed to be suppressed by our angels for the most part. We could not know that the seeds of the cataclysm that was 9/11 and the divisions that would follow were germinating beneath us.

The number of years since that horrible day has verily seen the transformation of who we are and how we are. No longer do we have a presumption of goodwill toward those who are politically, religiously, or philosophically different from us. Yes, we have always borne the demons of racism and intolerance through our nation’s shared history, but there was almost always the patina of unity among us save for the years of the Civil War. Rather, we are now in a season of distrust and tribalism where each partisan seeks to win leverage for the sake of power alone only for those of like mind and mission.

The most insidious part of this darkening of our nation is the democratization of truth and the obfuscation of our understanding of reality. A lie told a million times on social media becomes fact. No longer can we count upon rationality, logic, and evidence to be the measures we employ to discern truth. Truth has been abducted to serve the mission of elevating influence, gaining advantage, and exercising power. It is a rot that is destroying us and creating many victims. The internet, formerly and quaintly referred to as the information superhighway, has become our road to perdition and the chief means of the purveyance of agenda-driven disinformation coming from both extremes of the political spectrum. The algorithms move us into our demagogic poles and obliterate the common ground where consensus suffocates from lack of oxygen.

This organized perpetration of deception has taken on more meaning as we have faced the last century’s most critical public health threat. Freedom which was once defined as something that required a personal sacrifice of individual concerns in deference to the needs of others and the community has now become rebranded as solely within the province of individual liberty. The simple acts of individuals wearing masks or getting vaccinated to protect all of us and ending the pandemic for our towns, cities, states, nations is too much for many among us who have distilled their catalyzed grievances into refusals to sacrifice their “personal freedom.”

Indeed, as I write these words, state legislatures, including our own in my state, are codifying this movement into law with bans on companies including hospitals, nursing homes, and medical facilities from requiring COVID-19 vaccination for their employees. And, those legislators are doing it not because of some sincerely held principles, but because they know which way the wind blows and cynicism Trumps all other considerations in getting reelected.

The victims of this now distorted concept of liberty are ones that we physicians encounter every day. The one that inspired this essay for me is an 11-year-old boy that I saw three weeks ago. He is a patient of mine in my pediatric practice who came to see me with typical respiratory symptoms that led to a diagnosis of COVID-19. While he recovered uneventfully, his father got sick the next day and died from the same illness five days later. Like the vast majority of people who die from COVID-19 now, he was unvaccinated, believing that getting vaccinated was unnecessary and part of a greater effort to undermine his personal liberty. His son is now dealing with the unimaginable grief of losing a parent at such a tender age and asking his mother if he killed his father by getting sick and causing his death. This happens every day now in our communities across our nation. These are wounds that will never heal for this generation of kids.

We have no hope of exiting this pathway to darkness unless we can collectively rise above our manufactured grievances and reductive individualism to truly witness and love each other. We must recognize and reconcile the real harms done to each other in the evil pursuit of purely selfish interests. Only then can we renew and rekindle the true light of a successful community and our city on the hill.