what is meant by natural immunity to parasites?
Natural defence mechanisms (or innate factors) against malaria are most apparent in populations continually exposed to malaria parasites. For example, inherited conditions such as sickle cell anaemia and beta-thalassaemia, which cause deformities in red blood cells and are common in people from malarious regions, make it more difficult for malaria parasites to infect red blood cells.
Some people have red blood cells that lack proteins called Duffy antigens on their surface. These proteins act as receptors for Plasmodium vivax merozoites, so people without Duffy antigens are resistant to infection from this parasite.
Feature: Malaria versus the human genome
People residing in malaria-endemic regions acquire immunity to malaria through natural exposure to malaria parasites. Children living in areas of stable malaria transmission become infected early in life, and experience more severe disease symptoms during the first five years of life. But as immunity develops the disease becomes less severe and the number of parasites circulating in the blood declines. The acquired immune response to malaria is strain specific and is lost if a person moves away from a malaria endemic area.
Natural immunity to parasites refers to the body's ability to defend itself against parasitic infections without prior exposure or immunization. It is an innate defense mechanism that relies on various components of the immune system to recognize and eliminate parasites.
When parasites enter the body, the immune system recognizes them as foreign invaders and activates different defense mechanisms to neutralize or eliminate them. The immune response involves both innate and adaptive immunity. Innate immunity provides general, nonspecific defense mechanisms, whereas adaptive immunity specifically targets and eliminates parasites.
The innate immune response includes physical barriers such as the skin and mucous membranes, as well as cells like macrophages and dendritic cells that engulf and destroy parasites. These cells also release chemical signals called cytokines that stimulate the adaptive immune response.
The adaptive immune response involves specialized cells called T and B lymphocytes. T cells recognize the specific antigens presented by infected cells and destroy them. B cells produce antibodies that bind to the parasites, marking them for elimination by other immune cells. This process is known as humoral immunity.
To achieve natural immunity to parasites, it is crucial to maintain overall health and hygiene, as well as adhere to preventive measures such as proper sanitation, safe food handling, and avoiding exposure to parasite-infested areas. Regular exercise, a balanced diet, and adequate sleep can also strengthen the immune system, making it more effective in combating parasites.
In summary, natural immunity to parasites is the body's inherent ability to defend itself against parasitic infections through a combination of physical barriers, cellular responses, and humoral immunity. Maintaining good hygiene practices and a healthy lifestyle can enhance the body's natural defense mechanisms against parasites.