People who have fought off the COVID-19 virus would be deliberately reinfected in a first-of-its-kind trial at the University of Oxford that might shed light on how to develop more effective vaccines against the pathogen.
Researchers are looking for 64 healthy, previously infected volunteers from 18 to 30 years old to be studied under controlled, quarantined conditions for at least 17 days, the university said yesterday.
Participants would be infected with the original strain from Wuhan, China, and followed for a year.
Photo: AFP
Initial data from the Oxford study should be available within several months, helping vaccine developers look at levels and types of immunity needed to prevent reinfection, and how long protection persists.
Challenge trials, involving deliberate, supervised infections, are seen as particularly helpful for answering questions like these, because they allow scientists to scrutinize the details of how the body confronts the virus and vice versa.
While vaccines and previous infections provide some immune protection against the novel coronavirus, concerns and doubts remain about how long it lasts.
A recent study indicated that as much as 10 percent of previously infected young adults were reinfected, underscoring the need for effective vaccines to prevent spread, and Pfizer’s CEO has said that booster shots might be needed to maintain the immunity provided by the initial two doses of the company’s shot.
“The point of this study is to determine what kind of immune response prevents reinfection,” said Helen McShane, a professor of vaccinology at the University of Oxford, and chief investigator on the study.
McShane said the team would measure the levels of various components of participants’ immune response — including T-cells and antibodies — and then track whether participants became reinfected when exposed to the virus.
The first phase of the trial would initially involve 24 participants split into dose groups of three to eight people who would receive, via the nose, the original strain of COVID-19. The idea is to start with a very low dose and, if necessary, increase the dose — up to a point — between groups.
“Our target is to have 50 percent of our subjects infected, but with no, or only very mild, disease,” McShane said, adding that once the dose required to achieve this is determined, it would be administered to 10 to 40 other participants to confirm the dose.
The second phase of the study — expected to start in the summer — would involve a new group of participants and would study closely their immune response before and after exposure to the virus, as well as the level of virus and symptoms in those who become reinfected.
Should reinfection be confirmed, or symptoms develop, in either phase of the trial, participants would be given a monoclonal antibody treatment.
The Oxford study “has the potential to transform our understanding by providing high-quality data on how our immune system responds to a second infection,” said Shobana Balasingam, a research adviser at the Wellcome Trust, which is providing funds.
The findings could “inform not just vaccine development, but also research into the range of effective treatments that are also urgently needed,” she said.
The earliest volunteers in the world’s first human challenge trial involving COVID-19, conducted by Imperial College London, left quarantine late last month.
Critics of challenge trials have pointed out the ethical dangers of infecting people without being sure of its long-term consequences.
The Oxford researchers said that all those enrolled would be completely fit, well and recovered from their first COVID-19 infection.
Chinese President Xi Jinping (習近平) is to visit Russia next month for a summit of the BRICS bloc of developing economies, Chinese Minister of Foreign Affairs Wang Yi (王毅) said on Thursday, a move that comes as Moscow and Beijing seek to counter the West’s global influence. Xi’s visit to Russia would be his second since the Kremlin sent troops into Ukraine in February 2022. China claims to take a neutral position in the conflict, but it has backed the Kremlin’s contentions that Russia’s action was provoked by the West, and it continues to supply key components needed by Moscow for
Japan scrambled fighter jets after Russian aircraft flew around the archipelago for the first time in five years, Tokyo said yesterday. From Thursday morning to afternoon, the Russian Tu-142 aircraft flew from the sea between Japan and South Korea toward the southern Okinawa region, the Japanese Ministry of Defense said in a statement. They then traveled north over the Pacific Ocean and finished their journey off the northern island of Hokkaido, it added. The planes did not enter Japanese airspace, but flew over an area subject to a territorial dispute between Japan and Russia, a ministry official said. “In response, we mobilized Air Self-Defense
CRITICISM: ‘One has to choose the lesser of two evils,’ Pope Francis said, as he criticized Trump’s anti-immigrant policies and Harris’ pro-choice position Pope Francis on Friday accused both former US president Donald Trump and US Vice President Kamala Harris of being “against life” as he returned to Rome from a 12-day tour of the Asia-Pacific region. The 87-year-old pontiff’s comments on the US presidential hopefuls came as he defied health concerns to connect with believers from the jungle of Papua New Guinea to the skyscrapers of Singapore. It was Francis’ longest trip in duration and distance since becoming head of the world’s nearly 1.4 billion Roman Catholics more than 11 years ago. Despite the marathon visit, he held a long and spirited
China would train thousands of foreign law enforcement officers to see the world order “develop in a more fair, reasonable and efficient direction,” its minister for public security has said. “We will [also] send police consultants to countries in need to conduct training to help them quickly and effectively improve their law enforcement capabilities,” Chinese Minister of Public Security Wang Xiaohong (王小洪) told an annual global security forum. Wang made the announcement in the eastern city of Lianyungang on Monday in front of law enforcement representatives from 122 countries, regions and international organizations such as Interpol. The forum is part of ongoing