How quickly does COVID immunity fade? What scientists know

Cassandra Willyard

Nature | February 02, 2023

A kiosk in Shanghai, China, offers free SARS-CoV-2 testing.Credit: CFOTO/Future Publishing via Getty

Three years into the pandemic, the immune systems of the vast majority of humans have learnt to recognize SARS-CoV-2 through vaccination, infection or, in many cases, both. But just how quickly do these types of immunity fade?

New evidence suggests that ‘hybrid’ immunity, the result of both vaccination and a bout of COVID-19, can provide partial protection against reinfection for at least eight months¹. It also offers greater than 95% protection against severe disease or hospitalization for between six months and a year after an infection or vaccination, according to estimates from a meta-analysis². Immunity acquired by booster vaccination alone seems to fade somewhat faster.

China approves first homegrown COVID antiviral

The country’s drug regulator has granted conditional authorization for an HIV drug to be used to treat COVID-19.

Yvaine Ye

Nature | July 26, 2022

A temporary hospital for people with COVID-19 in Shanghai. The country has approved the first antiviral for the disease made in China. Credit: Ray Young/Feature China/Future Publishing/Getty

China’s drug regulator granted conditional approval on Monday for an HIV drug to be used to treat COVID-19. The drug, Azvudine, developed by Chinese drugmaker Genuine Biotech, is the first oral antiviral for the disease made in China.

Genuine Biotech, headquartered in Pingdingshan, applied for regulatory approval earlier this month. In an announcement, the company said that 40% of people with COVID-19 who were given Azvudine for a week in a phase III clinical trial showed “improved clinical symptoms”, compared with 11% of those given a placebo. However, detailed data from the trial, including whether the treatment reduced the risk of hospitalization or death, have not been released.

How months-long COVID infections could seed dangerous new variants

Tracking SARS-CoV-2 evolution during persistent cases provides insight into the origins of Omicron and other global variants. What can scientists do with this knowledge?

Ewen Callaway

Nature | June 15, 2022

These are mutations that accumulated in the spike protein of SARS-CoV-2 during a seven-month-long infection.Illustration by Nik Spencer/Nature; Source: Ref. 1

Virologist Sissy Sonnleitner tracks nearly every COVID-19 case in Austria’s rugged eastern Tyrol region. So, when one woman there kept testing positive for months on end, Sonnleitner was determined to work out what was going on.

Before becoming infected with SARS-CoV-2 in late 2020, the woman, who was in her 60s, had been taking immune-suppressing drugs to treat a lymphoma relapse. The COVID-19 infection lingered for more than seven months, causing relatively mild symptoms, including fatigue and a cough.

Sonnleitner, who is based at a microbiology facility in Außervillgraten, Austria, and her colleagues collected more than two dozen viral samples from the woman over time and found through genetic sequencing that it had picked up about 22 mutations (see ‘Tracking spike’s evolution’). Roughly half of them would be seen again in the heavily mutated Omicron variants of SARS-CoV-2 that surged around the globe months later¹. “When Omicron was found, we had a great moment of surprise,” Sonnleitner says. “We already had those mutations in our variant.”

China, Cuba Present Jointly-Produced ‘Pan-Corona Vaccine’

teleSUR | June 03, 2022

Cuba and China present the first patent for the Pancorona vaccine, result of the collaboration between both countries in the biotechnological field. | Photo: Twitter @EmbacubaChina

Cuba managed to develop five COVID-19 vaccines and inoculated 95% of its population against the COVID-19 virus, despite the burden of the U.S. blockade. China, likewise, produced a massive amount of two different vaccines for its 1.4 billion-strong population and much of the Third World.

Cuba and the People’s Republic of China jointly filed the first patent for a vaccine against  COVID-19 and its many variants, which could also be effective against several related viruses, the Cuban daily Granma reported on Thursday.

Most US kids have caught the coronavirus, antibody survey finds

Study shows that infections in very young children doubled during the Omicron wave.

Smriti Mallapaty

Nature | May 05, 2022

Credit: Sarah Silbiger/UPI/Shutterstock

Roughly two in every three children aged between one and four years old in the United States have been infected with SARS-CoV-2, according to a nationwide analysis¹. Infections in that age group increased more than in any other during the Omicron wave, which researchers say demonstrates the variant’s high transmissibility.

Researchers looked for COVID-19 antibodies in blood samples from more than 86,000 children under 18 years old — including some 6,100 children aged between one and four. In the youngest children, the number of infections more than doubled, from 33% to 68% between December 2021 and February 2022.

The Road Will Be Long And Bumpy: WEF On Post-pandemic Recovery

Countercurrents | January 12, 2022

The World Economic Forum (WEF) warns: The effects of the Covid-19 pandemic may take years to reign in. The WEF has also sheds light on major concerns regarding the future from the globe’s economic elite.

“Covid-19 and its economic and societal consequences continue to pose a critical threat to the world. Vaccine inequality and a resultant uneven economic recovery risk compounding social fractures and geopolitical tensions,” said the new Global Risks Report released by the WEF on Tuesday states.

The report is based on opinions of nearly 1,000 global risk experts and leaders from business, civil services, government, academic, and other spheres.

Omicron’s feeble attack on the lungs could make it less dangerous

Mounting evidence from animal studies suggests that Omicron does not multiply readily in lung tissue, which can be badly damaged in people infected with other variants.

Max Kozlov

Nature | January 06, 2022

A doctor in Uzhhorod, Ukraine, examines the lungs of a person with COVID-19. The Omicron variant might affect the lungs less than do previously circulating variants.Credit: Serhii Hudak/Ukrinform/Barcroft Media via Getty

Early indications from South Africa and the United Kingdom signal that the fast-spreading Omicron variant of the coronavirus SARS-CoV-2 is less dangerous than its predecessor Delta. Now, a series of laboratory studies offers a tantalizing explanation for the difference: Omicron does not infect cells deep in the lung as readily as it does those in the upper airways.

“It’s a very attractive observation that might explain what we see in patients,” says Melanie Ott, a virologist at the Gladstone Institute of Virology in San Francisco, California, who was not involved in the research. But she adds that Omicron’s hyper-transmissibility means that hospitals are filling quickly — despite any decrease in the severity of the disease it causes.

India’s Post-Pandemic Economic Recovery

Prabhat Patnaik

People’s Democracy | December 12, 2021

THE pandemic alas is not yet over, but there are no economic disruptions in the current fiscal year in the form of lockdowns or workers’ absence. The economy’s performance therefore can no longer be attributed to the prevalence of the pandemic; whatever it is, it is caused by economic factors.

Government spokesmen are busy claiming that the economy is displaying a robust recovery, and that the current fiscal year will post a double-digit growth rate. But a double-digit growth rate in the current year means nothing; since the previous fiscal year had witnessed a sharp absolute drop in GDP, in fact one of the sharpest among all countries of the world because of the government’s imposing a lock-down more stringent than anywhere else, a drop amounting to a staggering 24 per cent in the April-June quarter of 2020, a bounce back from such a trough is naturally to be expected; there is nothing to crow about it. The real question is how the current fiscal year’s performance compares with that of the pre-pandemic fiscal year, i.e., with 2019-20. And on doing so, we find that the first quarter’s GDP this year was well below that of the first quarter of 2019-20. The second quarter’s GDP is about the same as the GDP of the second quarter of 2019-20 (in fact it is just marginally higher by 0.3 per cent). In other words, given the 7.3 per cent drop in GDP last year compared to the previous year, even a double-digit growth rate of 10 per cent, which is higher than what government agencies like the State Bank of India are projecting for the current year (which is 9.5 per cent), will just about put the current year’s GDP 1.97 per cent above what it was in 2019-20; this is hardly indicative of a positive trend in the economy.

Cuba Works on Vaccines Against New COVID-19 Variant

teleSUR | December 02, 2021

Cuban scientists working in the development of vaccines, Cuba, 2021 | Photo: EFE

BioCubaFarma announced on Wednesday that Cuban scientists are now working to develop new vaccines to fight the new strain of Coronavirus.

Eduardo Martinez, president of BioCubaFarma, announced on Wednesday, Dec. 1, that Cuban scientists are working to develop a new variant of vaccines to strike strains like Omicron of the Coronavirus.

A socialist reply to ‘leftwing’ antivax disinformation

Antivaxxers of all stripes are a threat to public health

Cliff Conner

Climate and Capitalism | November 29, 2021

Cliff Connor is the author of A People’s History of Science and The Tragedy of American Science. This article was first published in Against the Current.

In the United States, most of the Covid antivax agitation comes from rightwing sources. It is dangerous and reprehensible because it threatens legitimate public health efforts to bring a pandemic under control that has already killed at least 750,000 people in the U.S. and five million worldwide. The rightwing ideologues who carry out this campaign of disinformation are simply unconscionable scoundrels.

Unfortunately, they have “leftwing” ideological allies who devise rationales designed to appeal to progressive-minded people. A blog post entitled “The Snake-Oil Salesmen and the COVID-Zero Con: A Classic Bait-And-Switch for a Lifetime of Booster Shots (Immunity as a Service)” provides a prime example.