COVID-19 | Immunity

Post Reply
Howzitgoing
Posts: 69
Joined: Mon Jul 13, 2020 8:37 am

COVID-19 | Immunity

Post by Howzitgoing »

Fortunately the scientific community is beginning to present some interesting questions, guesses and research about immunity in COVID-19 patients.

https://www.nytimes.com/2020/11/17/heal ... unity.html
Immunity to the Coronavirus May Last Years, New Data Hint
> Years, maybe even decades, according to a new study.
> Study not peer-reviewed.

Eight months after infection, most people who have recovered still have enough immune cells to fend off the virus and prevent illness, the new data show. A slow rate of decline in the short term suggests, happily, that these cells may persist in the body for a very, very long time to come.

The research, published online, has not been peer-reviewed nor published in a scientific journal. But it is the most comprehensive and long-ranging study of immune memory to the coronavirus to date.

“That amount of memory would likely prevent the vast majority of people from getting hospitalized disease, severe disease, for many years,” said Shane Crotty, a virologist at the La Jolla Institute of Immunology who co-led the new study.

The findings are consistent with encouraging evidence emerging from other labs. Researchers at the University of Washington, led by the immunologist Marion Pepper, had earlier shown that certain “memory” cells that were produced following infection with the coronavirus persist for at least three months in the body.

A study published last week also found that people who have recovered from Covid-19 have powerful and protective killer immune cells even when antibodies are not detectable.

In recent months, reports of waning antibody levels have created worry that immunity to the coronavirus may disappear in a few months, leaving people vulnerable to the virus again.

But many immunologists have noted that it is natural for antibody levels to drop. Besides, antibodies are just one arm of the immune system.

Although antibodies in the blood are needed to block the virus and forestall a second infection — a condition known as sterilizing immunity — immune cells that “remember” the virus more often are responsible for preventing serious illness.

Dr. Sette and his colleagues recruited 185 men and women, aged 19 to 81, who had recovered from Covid-19. The majority had mild symptoms not requiring hospitalization; most provided just one blood sample, but 38 provided multiple samples over many months.

The team tracked four components of the immune system: antibodies, B cells that make more antibodies as needed; and two types of T cells that kill other infected cells. The idea was to build a picture of the immune response over time by looking at its constituents.

“If you just look at only one, you can really be missing the full picture,” Dr. Crotty said.

He and his colleagues found that antibodies were durable, with modest declines at six to eight months after infection, although there was a 200-fold difference in the levels among the participants. T cells showed only a slight, slow decay in the body, while B cells grew in number — an unexpected finding the researchers can’t quite explain.

The study is the first to chart the immune response to a virus in such granular detail, experts said. “For sure, we have no priors here,” Dr. Gommerman said. “We’re learning, I think for the first time, about some of the dynamics of these populations through time.”

Exactly how long immunity lasts is hard to predict, because scientists don’t yet know what levels of various immune cells are needed to protect from the virus.

[More]

https://www.biorxiv.org/content/10.1101 ... 5.383323v1
Immunological memory to SARS-CoV-2 assessed for greater than six months after infection
Howzitgoing
Posts: 69
Joined: Mon Jul 13, 2020 8:37 am

Re: COVID-19 | Immunity

Post by Howzitgoing »

"RE-INFECTION CAN HAPPEN TO ANYONE: 26-year old world class cyclist Gaviria caught #COVID19 in February—hospitalized for 2 weeks. Prevailing wisdom suggested he’d at least be immune for foreseeable future. He was wrong. Reinfected 8 months later. Worrisome."

Colombia’s Fernando Gaviria
Colombia’s Fernando Gaviria.jpg
Colombia’s Fernando Gaviria.jpg (64.07 KiB) Viewed 1295 times
https://www.wsj.com/articles/the-pro-cy ... 1606919308
The Pro Cyclist Who Caught Covid Twice
Howzitgoing
Posts: 69
Joined: Mon Jul 13, 2020 8:37 am

Re: COVID-19 | Immunity

Post by Howzitgoing »

Immunity after COVID-19? New data suggests otherwise. Sheesh.

Hospitalized Again. And Again.

Significant numbers of coronavirus patients experience long-term symptoms that send them back to the hospital, taxing an already overburdened health system.


Nearly a year into the pandemic, it’s clear that recovering from Covid-19’s initial onslaught can be an arduous, uneven journey. Now, studies reveal that a significant subset of patients are having to return to hospitals, sometimes repeatedly, with complications triggered by the disease or by the body’s efforts to defeat the virus.

Even as vaccines give hope for stopping the spread of the virus, the surge of new cases portends repeated hospitalizations for more patients, taxing medical resources and turning some people’s path to recovery into a Sisyphean odyssey that upends their lives.

Data on rehospitalizations of coronavirus patients are incomplete, but early studies suggest that in the United States alone, tens of thousands or even hundreds of thousands could ultimately return to the hospital.

Many rehospitalized patients have respiratory problems, but some have blood clots, heart trouble, sepsis, gastrointestinal symptoms or other issues, doctors report. Some have neurological symptoms like brain fog, “a clear cognitive issue that is evident when they get readmitted,” said Dr. Vineet Chopra, chief of hospital medicine at the University of Michigan, who co-wrote the Michigan study. “It is there, and it is real.”

https://www.nytimes.com/2020/12/30/heal ... e=Homepage
He Was Hospitalized for Covid-19. Then Hospitalized Again. And Again.
curncman
Posts: 1348
Joined: Fri Jun 26, 2020 8:27 am

Re: COVID-19 | Immunity

Post by curncman »



Dr. Mark Sulkowski discusses our fundamental understanding of immunology and virology as they pertain to COVID-19 transmission, disease course, and potential routes for treatment. Topics: *Infection and immune response timeline *Types of immunity and impact on treatment methods *Assessing treatments: monoclonal antibodies and convalescent plasma *Strain variants and possible resistance to antibodies and reinfection
curncman
Posts: 1348
Joined: Fri Jun 26, 2020 8:27 am

New easy-to-use COVID-19 pills come with a catch

Post by curncman »

New easy-to-use COVID-19 pills come with a catch
Image
https://www.yahoo.com/news/explainer-ea ... 31469.html

Newly infected COVID-19 patients have two new treatment options that can be taken at home.

But that convenience comes with a catch: The pills have to be taken as soon as possible once symptoms appear.

The challenge is getting tested, getting a prescription and starting the pills in a short window.

U.S. regulators authorized Pfizer's pill, Paxlovid, and Merck’s molnupiravir last week. In high-risk patients, both were shown to reduce the chances of hospitalization or death from COVID-19, although Pfizer's was much more effective.

A closer look:

WHO SHOULD TAKE THESE PILLS?

The antiviral pills aren’t for everyone who gets a positive test. The pills are intended for those with mild or moderate COVID-19 who are more likely to become seriously ill. That includes older people and those with other health conditions like heart disease, cancer or diabetes that make them more vulnerable. Both pills were OK'd for adults while Paxlovid is authorized for children ages 12 and older.

WHO SHOULDN'T TAKE THESE PILLS?

Merck’s molnupiravir is not authorized for children because it might interfere with bone growth. It also isn't recommended for pregnant women because of the potential for birth defects. Pfizer's pill isn't recommended for patients with severe kidney or liver problems. It also may not be the best option for some because it may interact with other prescriptions a patient is taking. The antiviral pills aren't authorized for people hospitalized with COVID-19.

WHAT'S THE TREATMENT WINDOW?

The pills have to be started as soon as possible, within five days of the start of symptoms. Cough, headache, fever, the loss of taste or smell and muscle and body aches are among the more common signs. The Centers for Disease Control and Prevention offers a website to check your symptoms.

Dr. Cameron Wolfe, an infectious disease specialist at Duke University Hospital, advises getting a test as soon as you have symptoms of COVID-19.

“If you wait until you have started to get breathless, you have already to a large extent missed the window where these drugs will be helpful,” Wolfe said.

WHERE CAN I GET THE PILLS?

You'll need a prescription first from a doctor or other authorized health worker. The U.S. government is buying the pills from Merck and Pfizer and providing them for free, but supplies will be limited initially. They'll be shipped to states where they will be available at drugstores, community health centers and other places. Treatment lasts five days.

Some pharmacists may be able to administer a quick COVID-19 test and prescribe the pills all in one visit. They already do this in many states for flu or strep throat.

WILL THE PILLS WORK FOR THE OMICRON VARIANT?

The pills are expected to be effective against omicron because they don’t target the spike protein where most of the variant’s worrisome mutations reside. The two pills work in different ways to prevent the virus from reproducing.

ARE THERE OTHER OPTIONS FOR NEW COVID-19 PATIENTS?

Yes, but they aren't as easy to use as a pill: They are given by IV or injection, typically at a hospital or clinic. Three drugs provide virus-fighting antibodies, although laboratory testing suggests the two aren’t effective against omicron. British drugmaker GlaxoSmithKline's antibody drug appears to work, and officials say they are working to increase the U.S. supply. The only antiviral drug approved in the U.S., remdesivir, is for people hospitalized with COVID-19.
Post Reply