Oxford starts study to reinfect recovered COVID-19 patients

LONDON: People who have fought off the COVID-19 virus will be deliberately reinfected in a first-of-its-kind trial at the University of Oxford that may shed light on how to develop more effective vaccines against the pathogen, Bloomberg reported on Monday.
Researchers are looking for 64 healthy, previously Covid-infected volunteers from 18 to 30 years old to be studied under controlled, quarantined conditions for at least 17 days, the UK university said Monday.
Participants will be infected with the original strain from Wuhan, China and followed for a year.
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 Coronavirus, concerns and doubts remain about how long it lasts.
A recent study indicated that as much as 10% of previously infected young adults were reinfected, underscoring the need for effective vaccines to prevent spread, and Pfizer Inc's chief executive officer has said that booster shots may be needed to maintain the immunity provided by the initial two doses of the company's shot.
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.
Meanwhile, British health officials are investigating a COVID-19 variant originating in India but as yet they do not have enough evidence to classify it is as a variant of concern, Susan Hopkins of Public Health England (PHE) said on Sunday.
Speaking on the Andrew Marr Show on BBC television, Hopkins said: "We have not got enough data about this variant yet to be able to clarify whether it's a variant of concern. We have put it as a variant under investigation."
"To escalate it up the ranking we need to know that it's increased transmissibility, increased severity, or vaccine-evading, and we just don't have that yet, but we're looking at the data on a daily basis." PHE has said it has identified 77 cases of the variant in Britain, Reuters reported.