In a new research, scientists have found out that immunity from coronavirus infection may not last very long. These findings were published in the pre-print platform medRxiv.
The study, which is the first of its kind, examined the antibody levels in people who had the coronavirus infection in the past. They evaluated these antibodies to see how long they last after an active infection.
The scientists on the study took samples from a local hospital to monitor antibody levels in patients and healthcare staff from three months, after their first symptoms appeared.
They evaluated a total of 102 people which included patients, healthcare workers and staff of the hospital, who agreed to provide their samples.
The study which is not peer-reviewed yet, found out that antibody levels rose higher and lasted longer in patients who were severe cases. The team conducting the study thought this might be because as these patients have more virus, so their bodies produce more antibodies to fight this virus.
They found out that only 60 percent of the patients had a strong antibody response at peak of the infection. When their blood was evaluated two months later, the team saw that just 16.7 percent of the patients had a potent antibody response. Antibody levels fell as much as 23-fold over just two months.
In some cases, the antibody response to the virus later even became undetectable.
The scientists also found out that though many people have a sufficient response to the virus, it is waning over a short span of time. People with severe infections also have antibodies that stay longer in their bodies compared to those with less severe infections.
The study has implications for the development of a vaccine, and the herd immunity, that scientists were hoping for.
Though immune system builds immunity in a number of ways, and antibody levels are the measurement of this response, these findings mean that people could re-infected easily in each peak of the pandemic and that vaccines may not protect them for long.
Infection usually presents the scientists with how the body will cope up with any infection and how effective might be a vaccine against an infection. It means that if the infection is giving someone protective antibodies for just two months or three months, the vaccine will be effective just as long.
People might need new booster shots every few months or on annual basis, especially the vulnerable population like people with serious underlying health issues and people of older ages.
Early results from the University of Oxford have shown that the coronavirus vaccine it is developing produces lower levels of antibodies in macaques than are seen in humans infected with the virus. While the vaccine appeared to protect the animals from serious infection, they still became infected and may have been able to pass on the virus.
Experts have also warned that this novel coronavirus may have the modus operandi as the other coronaviruses that cause the common cold. These coronaviruses can re-infect people very easily and often. This means that the protective immunity people generate doesn’t last very long.
Other scientists from the leading UK health organization have also suggested that the coming second wave of the pandemic in the winter may cause more damage in the populations as the virus with other common respiratory bugs of the winter, overwhelm the hospitals.
This will make the coronavirus infections challenging to track as many symptoms of these viruses are just like each other.
Another concern is that people spend more time indoors in poorly ventilated spaces in the winter. Poorly ventilated spaces are more likely to make the novel coronavirus spread more easily.
The Academy of Medical Sciences in the United Kingdom has come up with a “reasonable worst-case scenario”, in which the number of coronavirus related hospital deaths between September 2020 and June 2021 in the UK could be as high as 119,900.
This projection is more than double the 45,000 deaths the UK has experienced so far. This number does not include potential deaths in care homes, which have accounted for 30% deaths in England.
How can we prepare for potential healthcare challenges this winter? Our new report looks at possible scenarios and solutions – find out more: https://t.co/q5VqstoYAt #winterCOVID pic.twitter.com/GfTGEUixsd
— Academy of Medical Sciences (@acmedsci) July 14, 2020
Data from the latest study also suggests that the second peak in winter will reveal if indeed re-infections are a reality of this virus.