Severe COVID-19-associated T cell deficiency in the elderly; Antiseptic sprays may limit the spread of the virus


By Nancy Lapid

(Reuters) – The following novel is a roundup of some of the latest scientific studies on coronovirus and an attempt to treat and vaccine for the virus-causing disease COVID-19.

Deficiency of ‘naïve’ T cells increases COVID-19 risk in the elderly

Scientists say the low supply of a certain type of immune cell in older people, which is important for fighting off foreign invaders, may help clarify their vulnerability. When germs enter the body, the initial “innate” immune response produces inflammation not specifically targeted at bacteria or viruses.

Within days, more precise “adaptive” immune responses begin to produce antibodies against the attacker with T cells that either aid in antibody production or seek out and attack infected cells.

In a small study published Wednesday in Cell, COVID-19 patients with pus disease had better adaptive immune responses, and in particular, stronger T-cell responses to coronoviruses.

People over the age of 65 were more likely to have poor T cell reactions, and Shane Crotti, co-scientist at the La Jolla Institute for Immunology, said in a news release that there is poor reactive response.

As we age, our supply of “naive” T cells shrinks, he explained. Put another way, we have fewer “inexperienced” T cells that will activate to respond to a new invader. “The aging and depletion of innate T cells may be a risk factor for failure to produce a coordinated adaptive immune response, resulting in increased susceptibility to severe COVID-19,” the researchers said. (Https://bit.ly/3ks4FbG)

Antiseptic nasal sprays may help to spread coronovirus

An antiseptic nasal spray containing povidone-iodine may help prevent the transmission of new coronaviruses, preliminary research suggests.

In test tube experiments, a team of ear, nose, and throat doctors found that a povidone-iodine nasal spray reduced the virus in 15 seconds. The nasal spray that they tested is usually used to disinfect the inside of the nose before surgery. Researchers formulated for use on the skin by researchers are not safe in the nose.

He told JAMA Otolaryngology – Head and Neck Surgery on Thursday that he now has his patients use the spray before intranasal procedures to reduce the risk of transmission of the virus through the air via droplets and aerosol diffusion. Could.

They instruct patients to do nasal refinement before coming to appointments, “to reduce intranasal viral load and … to prevent spread to waiting areas and other common areas.” However, they caution that regular use of povidone-iodine will not be safe for some people, including pregnant women and patients with thyroid conditions. Researchers said large clinical trials have not yet proven that viral transmission is controlled by intranasal povidone-iodine solutions, but “these studies are already underway.” (Https://bit.ly/2RGjMSm)

Not all COVID-19 antibody tests are the same

Some COVID-19 antibody tests are much more reliable than others. But even with the best ones, reliability varies among patient subgroups, a new study suggests. Some tests look for IgM or IgA antibodies, the first antibodies produced by the immune system in response to an invader that does not remain in the body for long.

Other tests – the most common type – look for IgG antibodies, which usually develop within seven to 10 days after the onset of symptoms and remain in the blood for some time after the patient has recovered.

In a study posted to MedRixive on the first Wednesday of peer review, researchers analyzed data from 11,809 individuals whose COVID-19 was revealed by highly rated tests to see if different antibody assays Will “remember” that the patient was infected.

The most commonly used assays, looking for IgG, had a 91.2% recall rate. But IgA and IgM assays had estimated recall rates of 20.6% and 27.3%, respectively, Coauthor Natalie Schells of the United Group told Reuters. “Recall varies greatly among subtotals and, according to the timing of the tests, performance becomes relatively stable after 14 days,” she said. “The test performed better for men vs. women, for non-whites vs. whites, and for individuals over 45 years of age.” More research is needed to understand why these variations occur, Schells said. (Https://bit.ly/32FsiHD)

Open in an external browser for a Reuters graphic on https://tmsnrt.rs/3a5EyDh Vaccine and Treatment in Development.

(Reporting by Nancy Lapid; Editing by Bill Berrocott)

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