By Nancy Lapid
(Reuters) – The following is a summary of some of the latest scientific studies on the new coronavirus and efforts to find treatments and vaccines for COVID-19, the disease caused by the virus.
Immune system T cell responses to variants remain strong
Although worrying coronavirus variants identified in Brazil, South Africa, and California have mutations that may help them resist antibody treatments and vaccines, the immune system’s T cell responses to the variants are not affected in recovering patients and in people undergoing Modern Inc or Pfizer received. Inc / BioMTech SE vaccines, new data shows. “We think this is really good news,” said Alessandro Sette of the La Jolla Institute of Immunology, whose team on Monday reviewed the findings on bioRxiv before the peer review. The T cells induced by vaccines can recognize pieces of the virus vein protein, while T cells induced by previous infection recognize several parts of the virus, including the vein and other proteins, Sette said. “These pieces are largely not altered / mutated in the variants,” he explained. “This means that the T cell responses recognize the ‘ancestral’ series and the variants equally well.” While circulation of memory T cells would probably not prevent infection, it could reduce the severity of COVID-19, he added. T cell responses are known to be linked to a milder COVID-19, and may contribute to the limitation of COVID-19 caused by variants that escape partially or largely neutralizing antibodies. (https://bit.ly/384IAMo)
Asthma does not increase COVID-19 risks
Asthma itself is not a risk factor for hospitalization or worse COVID-19, and people whose asthma is caused by allergies may be at a lower risk, according to new research presented at the virtual annual meeting of the American Academy of Allergy, Asthma and Immunology was presented. Researchers at Stanford University studied 5,596 patients who tested positive for COVID-19 from March to September 2020. Of these, 11% were hospitalized, including 100 patients with asthma. “Following other medical conditions of patients associated with worse COVID-19 diseases, including high blood pressure, heart disease, diabetes and obesity, asthma is no longer a risk factor for hospitalization,” said Dr. Lauren Eggert. admitted to the hospital, asthma was not significantly associated with the severity of illness, she said, and researchers also found that patients with allergic asthma were nearly half as likely as patients with other types of asthma to require hospitalization. explanation, according to Eggert, is that the immune system in allergic asthma “underregulates” or reduces the production of ACE2 proteins on cell surfaces, which is an important gateway for the coronavirus (https://bit.ly/3reYR9j)
Antibodies to variants can provide cross-protection
Antibodies to a newer, more contagious coronavirus variant can prevent infection by earlier variants, laboratory studies indicate. In test tube experiments, researchers studied the neutralizing effects of antibodies obtained by people infected with COVID-19 in the first pandemic wave in South Africa, when the initial version of the virus was predominant, and in survivors of the second wave. , when a more contagious, more difficult-to-treat new variant prevails. First wave antibodies neutralized the first wave virus, but not the second wave virus. As expected, the second wave of antibodies neutralized the second wave of viruses. According to an article published on medRxiv on Saturday, they neutralized the first wave virus, although it was not as strong. At a news conference on Wednesday, co-author Alex Sigal of the Africa Health Research Institute said the findings offer hope that vaccines based on the variant can protect against these and other variants circulating worldwide. Pfizer, AstraZeneca Plc, Johnson & Johnson and Moderna are already developing vaccines based on the variant identified in South Africa. Salim Abdool Karim, a leading government adviser on COVID-19, predicted that by the end of 2021, most vaccine manufacturers will adjust their shots accordingly. (https://bit.ly/3rhXJSq; https://reut.rs/2MHJaZ8)
UK finds vaccines protect older people
The Pfizer and AstraZeneca vaccines are more than 80% effective in preventing COVID-19 hospitalizations in people older than 80 years after a single dose, Public Health England said on Monday, citing a study released on medRxiv before peer review . The UK study also found that two doses of the Pfizer vaccine in people over the age of 70 are approximately 85% to 90% effective in preventing symptomatic diseases. Recipients of Pfizer vaccines in that age group who did develop symptomatic infections had a 44% lower risk of hospitalization and a 51% lower risk of death compared with non-vaccinated patients. Since the two-dose AstraZeneca vaccine was only recently introduced, researchers only had data after one dose. The effect against symptomatic diseases was about 60% to 75%, and there was also a protective effect against hospitalization, the researchers said. They noted that the AstraZeneca data were collected while a more contagious variant was prevalent in the UK. Britain’s use of the AstraZeneca vaccine for the elderly contrasts with many European countries, which cited a lack of clinical trial data for their decision not to use it on older people. (https://bit.ly/3rktaLW; https://reut.rs/3kKIEX4)
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(Reporting by Nancy Lapid, Megan Brooks, Kate Kelland and Alexander Winning; Edited by Bill Berkrot)