How long can naturally acquired immunity from Covid-19 last? Study reveals interesting details

People who were infected with Covid-19 in the past has developed immunity towards the disease for several months, finds a new study conducted by Public Health England. The findings support similar studies around immunity from the disease.

Experts have, however, warned that people with immunity still have the chances of spreading infections as they are able to carry the virus in their throat or nose, without feeling ill. Hence the study claims that people who have recovered from the condition still needs to wear masks, wash their hands and maintain distance at least two meters from others.

How the study was conducted and what were the outcomes

The study was conducted on tens of thousands of healthcare workers across the UK starting from June 2020 for the presence of Covid-19 infections or antibodies. Scientists found 44 potential reinfections out of which 42 were cases of possible reinfection and two were probable reinfections among a total of 6,614 participants with Covid antibodies.

Out of the two probable cases of re-infections, both were infected with Covid-19 in the first phase but were not tested and reported having less severe symptoms during re-infection. Among the 44 potential reinfections cases, none has an RT-PCR test during the first wave but detected antibodies in their sample.

With these findings, researchers concluded that people who acquired natural immunity from SARS-CoV-2 virus from past infections has 83% protection against reinfection, compared to people without any history of catching the infection. The scientist further asserted that the immunity can last for anything up to five months from the day the person became sick from Covid-19 the first time.

What the study tells about Covid-19 immunity

How long a person can be immune from acquiring an infection various from disease to disease and one factor that determines longevity is the amount of neutralising antibodies produced inside the infected person when infected first. For example, if a person gets measles, he almost can never get the disease again. But in case of flu, the immunity is short-lived and people need to get vaccinated every year to keep infection at bay.

This week, another study published in a Science journal suggests the immunity that the body acquired from contracting Covid-19 infection once can last for eight months. The study was conducted on 188 patients with antibodies.

Scientists have been studying on the subject of duration of immunity to Covid-19 through the pandemic and all the studies have provided varied results. Another study conducted by researchers from King’s College London, however, finds one can lose immunity in months.