New research suggests there's a risk of catching covid-19 multiple times.

Scientists at Imperial College London have tracked 100,000 infected people over a period of three months and noticed their antibody response declined, especially in older people.

The team's found the number of people testing positive for antibodies, has fallen by 26 per cent.

Malaghan Institute director Graham Le Gros told Mike Hosking that raises serious questions about whether re-infection is likely.

"We're going to have to wait a few months to see whether the people that have lost antibodies, will get re-infected from the next wave in the UK."

Le Gros says the research shows herd immunity won't necessarily work. 

"They tracked nearly 100,000 people  over a period of three months, and they noticed the antibody response declined, especially in older people."

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