Adults 50 years and older who have not been vaccinated have up to 45 times more risk of ending up in the hospital than those who have a full schedule and booster, said Alejandro Sánchez, from the UNAM Biotechnology Institute.
“The human body cannot maintain an immune response all the time, but it does store memory cells., in such a way that when a reinfection occurs, these cells fire and begin to produce antibodies again, which will not recognize the omicron variant or other new ones because they do not have this memory. Hence the importance of reinforcement,” he said.
He added that the United States Centers for Disease Control and Prevention (CDC) announced that booster doses are essential and a critical tool for people who become infected with the omicron variant to have less likely to develop disease with severe symptoms, require hospitalization, or die.
“According to information from the CDC, booster doses reduce hospitalizations by 90 percent if the omicron variant is acquired, especially in older adults“, he referred.
Differences with natural immunity
He stated that people who have been infected with COVID develop natural immunity, and what has been seen with natural immunity is that when a new variant appears, it is not as strong as the one that a vaccine can generate; hence the relevance of getting vaccinated, having a complete scheme and getting a booster according to the indications of the health authorities.
He explained that “when a person is infected prior to vaccination and then is vaccinated, hybrid immunity is generated. This ultimately allows the immune system to remedy many of the symptoms of delayed or long COVID, the famous “long COVID”, and the immune response is focused or standardized in such a way that there are no inflammatory processes, as is seen with natural immunity.
People who finish their vaccination schedule and had a previous infection generate something called “superimmunity.” “It is hybrid immunity, but at a superlative extreme, in which, in the end, the protection is greater,” details the expert.