Variants of the virus have been found to be deadlier, more contagious; some can thwart vaccinations


(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.

FILE PHOTO: The ultrastructural morphology exhibited by the 2019 novel coronavirus (2019-nCoV), which was identified as the cause of an outbreak of respiratory disease first detected in Wuhan, China, is seen in an illustration published by the Centers for Disease Control and Prevention (CDC) in Atlanta, Georgia, USA January 29, 2020. Alissa Eckert, MS; Dan Higgins, MAM / CDC / Prospectus via REUTERS.

Several variants can “escape” from vaccines

Antibodies induced by the Moderna Inc and Pfizer Inc / BioNTech SE vaccines are dramatically less effective at neutralizing some of the most worrisome coronavirus variants, a new study suggests. The researchers obtained blood samples from 99 people who had received one or two doses of either vaccine and tested their vaccine-induced antibodies against virus replicas designed to mimic 10 variants circulating globally. Five of the 10 variants were “highly resistant to neutralization,” even when the volunteers had received both doses of the vaccines, the researchers reported Friday in Cell. All five highly resistant variants had mutations in the spike on the surface of the virus, known as K417N / T, E484K and N501Y, which characterize one variant rampant in South Africa and two variants that spread rapidly in Brazil. According to previous studies, the proportion of neutralizing antibodies was reduced by 5 to 6 times compared to the variants discovered in Brazil. Compared to the variant discovered in South Africa, neutralization was reduced from 20 to 44 times. A variant now circulating in New York has the E484K mutation. “While studies of the New York variant are ongoing, our findings suggest that similar variants harboring E484K may be more difficult for vaccine-induced antibodies to neutralize,” said study leader Alejandro Balazs of the University of Harvard and Massachusetts General Hospital. “Despite our results,” he added, “it is important to keep in mind that vaccines generate other types of immune responses that could protect against the development of serious disease.” (bit.ly/3bWB1Ko)

The variant identified in the UK is more lethal

The coronavirus variant first identified in the UK, known as B.1.1.7, is more lethal than other variants circulating there, a new study appears to confirm. The researchers analyzed data from 184,786 people in England diagnosed with COVID-19 between mid-November and mid-January, including 867 who died. For every three people who died within four weeks of being infected with another variant, about five died after being infected with B.1.1.7, according to a medRxiv article prior to peer review. Overall, the risk of death with B.1.1.7 was 67% higher than the risk with other variants in England, the authors said. As with previous variants, the risk of death for patients increased with age, male gender, and pre-existing medical conditions. B.1.1.7 is now prevalent throughout Europe and is projected to become prevalent in the United States. “Fundamentally,” the researchers wrote, “emerging data suggest that currently approved vaccines for SARS-CoV-2 are effective against B.1.1.7.” (bit.ly/3r2vpCE)

The variant identified in Brazil is doubly infectious

Between November and January in Manaus, Brazil, the frequency of COVID-19 cases involving the P.1 coronavirus variant increased from nonexistent to 73%, and the number of infections there quadrupled compared to what the city experienced in the first wave of the pandemic, according to a report published on medRxiv before peer review. The higher infectivity of the P.1 variant likely contributed to that, the report suggests. Based on national sanitary surveillance data, the authors estimate that the P.1 variant is approximately 2.5 times more transmissible than the previous variants circulating in Manaus. The spread of P.1 occurred despite the fact that 68% of the city’s population had already been infected with the original strain of the coronavirus, the researchers noted. In their analysis, the risk of reinfection with P.1 was low. The variant’s ability to cause severe disease, or its pathogenicity, is not yet clear. “The P.1 variant has already been detected in at least 25 countries,” the authors said. “This calls for urgent studies … of the P.1 variant, as increased transmissibility and pathogenicity can lead to collapse even in well-prepared health systems.” (bit.ly/38MGykw)

To prevent infection, the new CPR technique adds distance

To avoid coronavirus infection during cardiopulmonary resuscitation (CPR), medical professionals can increase their distance from the patient by doing chest compressions with the heel of the bare foot, known as leg-heel compression, instead of the hands, suggests a new study. The researchers had 20 medical professionals perform a standard manual chest compression followed by a leg-heel chest compression after brief instruction on a manikin. There was no difference in any of the measured variables, including correct heel placement for compression purposes, correct depth of chest compression, and rate of compression. The study found that the possible spread of respiratory droplets from the patient to the person performing CPR would likely be minimized by compression of the leg and heel. “In special circumstances such as the COVID-19 pandemic, leg-heel chest compression may be an effective alternative … compared to manual chest compression while significantly increasing distance to the patient,” the researchers concluded in a paper. posted Monday on medRiv. before peer review. (bit.ly/3ltWgX4)

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Reporting by Nancy Lapid; Additional reporting by Christine Soares. Editing by Bill Berkrot

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