posted on 8/28/2021 06:00
(credit: Silvio Ávila/AFP – 11/3/21)
Covid-19 caused by the Delta variant of Sars-CoV-2 doubles the risk of hospitalization compared to infection caused by the Alpha strain, which was identified earlier by scientists. British researchers reached this conclusion after evaluating medical data from more than 40,000 people who tested positive for the disease.
According to the authors of the work published in the journal The Lancet, the data obtained reinforce the need for vaccination of the population and attention to the possible impacts on the health structure due to the advance of the most transmissible form of the coronavirus.
The team analyzed medical information from 43,338 infected in England between March 29 and May 23, 2021, including information on vaccination status, need for emergency care and hospital admission. The researchers took blood samples from all volunteers and submitted the material to complete genome sequencing to confirm the variant responsible for the infection.
There was a higher rate of cases caused by the Alpha variant (80%), first identified in the UK, compared to Delta (20%), whose first cases appeared in India. “Although the proportion of Delta cases at the time we did the study was only 20%, it grew in the following months and now represents about two thirds of new covid-19 cases registered in the country, surpassing Alpha and becoming the dominant variant in England”, the authors detail.
After a comprehensive statistical analysis—which took into account factors already known to affect susceptibility to the severe form of covid-19, including age, ethnicity, and vaccination status—the researchers found that the risk of being admitted to a hospital was higher. than twice as much due to Delta infection compared to Alpha (2.26-fold increase). Considering the risk of hospitalization and the need for emergency care, the risk is 1.5 times higher.
“This study confirms suspicions that people infected with Delta are significantly more likely to need hospitalization than those with Alpha, something that has not yet been observed in a detailed study,” emphasizes, in a statement, Gavin Dabrera, a of the study’s lead authors and consultant epidemiologist at the National Service for Infection and Public Health in England.
Another interesting data obtained in the analysis reinforces the need to complete the vaccination against covid-19 to avoid infection with any variant of Sars-CoV-2. In the study, only 1.8% of covid-19 cases (with either strain) had received the full vaccine regimen. On the other hand, 74% of cases were not vaccinated and 24% were partially vaccinated.
“We already know that vaccination offers excellent protection against Delta and as this variant accounts for over 98% of covid-19 cases in the UK today, it is vital that those who have not received two doses of the immunizer do so as much as possible. as quickly as possible”, emphasizes Dabrera. “It is also important that, when presenting symptoms of the disease, the person stays at home and undergoes a PCR test as soon as possible”, he completes.
The authors consider that there are limitations to the study. They did not have access to information about patients’ preexisting health conditions, which affects vulnerability to covid-19. In addition, there is a risk of occurrence of non-controllable variables, such as changes in the hospital admission policy during the analysis period.
Despite the obstacles, they emphasize that the research is further proof of the importance of vaccination. “Our analysis highlights that, in the absence of vaccines, any Delta outbreak will pose a greater health burden than an Alpha epidemic. Full immunization is crucial to reducing an individual’s risk of hospitalization. It is essential to reduce the chances of serious disease caused by the Delta variant, and we are going to achieve this with the vaccine”, says Anne Presanis, one of the authors of the study and a researcher at the Biostatistics Unit at the University of Cambridge.
Test tube / Scientific facts of the week
credit: Jonathan Nackstrand / AFP – 8/17/19
Unusual rain in Greenland
The Danish Meteorological Institute reported a rare phenomenon in the Greenland ice cap, which occurred in the middle of the month. According to monitoring, it rained in the area, more than 3,000 meters above sea level. According to the US Snow and Ice Data Center (NSIDC), precipitation was observed for several hours on August 14 at the US Summit station. “Rain can only fall if the temperature is above, or slightly below, 0°C. So this is an extreme situation, because it may never have happened,” said Martin Stendel, a researcher at DMI. “It’s likely to be a sign of global warming,” he added. Temperatures were just above 0°C, which means the snow is melting and re-freezing to ice. According to the expert, this phenomenon happened only nine times in the last 2,000 years and, of these, three occurred in the last decade (2012, 2019 and 2021).
Russia postpones space mission
Russia announced the postponement of the launch of its Luna-25 spacecraft because of a problem with the descent system. Initially scheduled to take place in October and then rescheduled for 2022, the mission will be the first of its kind by Moscow since the 1970s. to the Moon. The American space agency (NASA) plans to send astronauts to the Earth satellite in 2024. Alexander Shirkhakov, director of NPO Lavochkin, the company that develops the Luna-25 spacecraft, explained that the delay was due to “certain problems detected during the tests”. He specifically mentioned the need to “develop a lunar landing system with absolute safety.” The Luna-25 project is the first step in a series of Russian missions, which aim to install an eventual base in orbit, or even on the lunar surface, built together with China.
115 million year old Brazilian pterosaur
Seized in a Federal Police operation in 2013, when it was about to be taken to Europe and traded with collectors, a pterosaur fossil, after eight years of study, proved to be one of the most complete in the Tapejaridae family in the world. Tupandactylus navigans, according to specialists, lived approximately 112 million years ago (in the Cretaceous period), in the area where the Araripe Basin is located, between Ceará, Pernambuco and Piauí. The fossil was described by a team led by paleontologist Victor Beccari, from the University of São Paulo, in a scientific article published in the American magazine Plos One. The work was carried out in partnership with the Federal University of Pampa, Universidade Estadual Paulista, Federal University of ABC and Universidade Nova de Lisboa, in Portugal. For the study, experts used a tomography of the fossil and built a 3D model of the animal, which had a large crest on its head. It is believed that, for this reason, the T navigans were incapable of long flights.
Between 35.6% and 95% of 20th-century ocean surface climates — defined by surface water temperature, pH and concentration of the mineral aragonite — could disappear by 2100. That will depend on 21st century greenhouse gas emissions, he says. to a study published in Scientific Reports. The authors, from the University of Northeast Boston, modeled ocean climates over three periods: early 19th century (1795–1834), late 20th century (1965–2004), and late 21st century (2065–2104). They then compared these modeled climates at various locations using two emission scenarios: the first, with peak emissions in 2050; and the second, in 2100. In both cases, the apex is followed by slow increases. Comparisons have shown that some 19th- and 20th-century ocean climates will no longer be found by the mid-21st. By 2100, 10% to 82% of the ocean’s surface may experience higher temperatures, more acidic pH, and lower aragonite saturation, a mineral that corals and other marine organisms use to form shells.