![](https://i.imgur.com/CLvY2jA.png")
10-03-2022, 08:31 AM
Josephine Ma
Published: 12:41pm, 8 Mar, 2022
......
Does someone who has already been infected need to be vaccinated? If they are vaccinated, should they get boosters?
The answer is yes, and yes. According to the United States Centres for Disease Control and Prevention (CDC), people who have already had Covid-19 and do not get vaccinated after their recovery are more likely to get Covid-19 again than those who get a jab after their recovery.
Since a booster can better protect a person from severe disease, health authorities in many countries advise people to get boosted even after infection, though guidelines vary.
In Singapore, for example, people can receive a booster 28 days after infection, although the recommendation is to be boosted three months after infection.
British health authorities are advising at least a four-week wait after infection before getting a booster, while in Hong Kong there is no urgency for recovered Covid-19 patients to have a third dose, although a first dose is advised.
......
unvaccinated adults admitted to hospital with Covid-19 were 5.49 times more likely to be reinfected 90 to 179 days later than those who had received two doses of the Pfizer/BioNTech vaccine but were never infected.
......
the chance of reinfection for the unvaccinated was 2.34 times higher than those who were fully vaccinated.
......
unvaccinated participants who had been infected with Covid-19 were found to have 86 per cent lower risk of reinfection compared to the risk of primary infection in those who had no previous infection and were also unvaccinated. But the protection wanes over time.
Double protection in people who were both infected and then double vaccinated was greater and more long lasting, standing at over 90 per cent after two doses. This protection remained strong more than a year after infection and more than six months following vaccination
......
How long will naturally-acquired protection last? And when should a person receive the first doses or a booster after recovering from infection?
Studies show that, in general, natural infection can protect for around six months, with immunity starting to wane after four to six months.
......
people who had two mRNA vaccine doses but were infected later had longer protection than those who were infected but unvaccinated.
......
If a person is infected by other variants and has recovered, will they be adequately protected against the Omicron variant?
Experience in South Africa, the first country hit by Omicron, showed that previous infection by other variants did little to prevent an Omicron infection.
......
Before mid-November, reinfections accounted for about 1 per cent of reported Covid-19 cases, but the rate has risen to around 10 per cent, according to the UK Health Security Agency.
https://www.scmp.com/news/china/science/...n-infected
Published: 12:41pm, 8 Mar, 2022
......
Does someone who has already been infected need to be vaccinated? If they are vaccinated, should they get boosters?
The answer is yes, and yes. According to the United States Centres for Disease Control and Prevention (CDC), people who have already had Covid-19 and do not get vaccinated after their recovery are more likely to get Covid-19 again than those who get a jab after their recovery.
Since a booster can better protect a person from severe disease, health authorities in many countries advise people to get boosted even after infection, though guidelines vary.
In Singapore, for example, people can receive a booster 28 days after infection, although the recommendation is to be boosted three months after infection.
British health authorities are advising at least a four-week wait after infection before getting a booster, while in Hong Kong there is no urgency for recovered Covid-19 patients to have a third dose, although a first dose is advised.
......
unvaccinated adults admitted to hospital with Covid-19 were 5.49 times more likely to be reinfected 90 to 179 days later than those who had received two doses of the Pfizer/BioNTech vaccine but were never infected.
......
the chance of reinfection for the unvaccinated was 2.34 times higher than those who were fully vaccinated.
......
unvaccinated participants who had been infected with Covid-19 were found to have 86 per cent lower risk of reinfection compared to the risk of primary infection in those who had no previous infection and were also unvaccinated. But the protection wanes over time.
Double protection in people who were both infected and then double vaccinated was greater and more long lasting, standing at over 90 per cent after two doses. This protection remained strong more than a year after infection and more than six months following vaccination
......
How long will naturally-acquired protection last? And when should a person receive the first doses or a booster after recovering from infection?
Studies show that, in general, natural infection can protect for around six months, with immunity starting to wane after four to six months.
......
people who had two mRNA vaccine doses but were infected later had longer protection than those who were infected but unvaccinated.
......
If a person is infected by other variants and has recovered, will they be adequately protected against the Omicron variant?
Experience in South Africa, the first country hit by Omicron, showed that previous infection by other variants did little to prevent an Omicron infection.
......
Before mid-November, reinfections accounted for about 1 per cent of reported Covid-19 cases, but the rate has risen to around 10 per cent, according to the UK Health Security Agency.
https://www.scmp.com/news/china/science/...n-infected
