How the immune system responds to coronavirus has been essential in studying the virus as well as vaccine developments. Recent findings from the largest antibody study in England suggests that immunity against the virus is waning.
More than 360,000 people took part in Imperial College London's Real-Time Assessment of Community Transmission (REACT) study between June and September. Using home finger-prick tests, the researchers kept track of coronavirus antibodies to understand infection rates.
By September, positive tests decreased by 26.5%. The trend was similar across all age groups in England except for medical health workers, most likely due to continuous and high exposure to the live virus.
Decline of Antibodies
The authors took note that there was "a significant decline in the proportion of the population with detectable antibodies" during rounds of home tests after the first wave of infections in the country. Their results also agreed with earlier studies that asymptomatic people are more likely to have decreased levels of antibodies compared to those with severe infections.
Younger patients who had recovered from the virus also had a slower loss of antibodies compared to senior citizen patients over 75 years old who survived as well. However, there remains insufficient data to determine if antibodies can provide effective immunity. It is also difficult to predict how likely it would be for patients to get reinfected by Covid-19.
During the study, 17,576 tested positive for the virus. Nearly one-third that tested positive were asymptomatic. In general, antibody prevalence in June was at 6% which dropped to 4.4% by September.
Professor Paul Elliot said that testing positive for antibodies do not guarantee immunity to the virus. Those with a significant number of antibodies should still follow public safety guidelines such as physical distancing and wearing face masks.
Read Also: Scientists Found A Breakthrough Antibody That 'Neutralizes' Coronavirus: Here's How it Works
Antibodies and Immunity
In agreement, Helen Ward said it remains uncertain whether people with detectable antibodies are safe from the reinfection of Covid-19. Nevertheless, the government recognizes that the research can help them necessary actions to control the spread of the virus.
Dr. Claudi Hoyen from University Hospitals of Cleveland shared that the study suggests that in terms of antibodies, Covid-19 is similar to other coronaviruses.
For example, with the common cold, antibodies wane, allowing people to get the cold several times. At the same time, younger people and those with strong immune systems have a slower decline in antibodies compared to older people. The study also suggests that those who have recovered from the virus may be contagious again.
The antibody study would allow researchers to make better predictions regarding immunity, compared to other attributes of the virus that "has been so off the wall," expressed Hoyen. Regarding wearing face masks and other safety measures, she "think[s] the sooner we resolve ourselves to the fact that this is what we have to do to get through this, we can accept it and move on."
Read Also: AstraZeneca/Oxford Vaccine Shows Good Immune Responses in Older Adults
Check out more news and information on the Coronavirus on Science Times.