How An Insect Bite Can Affect Your Immune System
Malaria is one of the world's deadliest infectious diseases. It is caused by a parasite spread by mosquito bites. It is common in the tropical and subtropical regions of Africa, South and Central America, and the Middle East, and frequently occurs in children. Many people who get sick and then recover continue to have bouts with the disease throughout their lives.
The parasites that cause malaria reproduce in the red blood cells. When their reproductive cycle ends, the cells burst open and the parasites rush out to spread to other cells and begin the cycle all over again. As the red blood cells burst, the host experiences all or some of the following symptoms:
- high fever
- chills and shaking
- precipitous drops in body temperature accompanied by profuse sweating
- nausea and vomiting
- malaise (a vague feeling of uneasiness and discomfort)
The symptoms pass as the body recovers but then begin all over again when the next set of cells rupture.
How Malaria Affects the Immune System
The parasite responsible for malaria is tricky. It can fool the immune system. It forms knobs made up of proteins on the surface of the cells it infects. These knobs keep the cell anchored to the wall of the blood vessels. Usually, the immune system would remove the infected cell to the spleen for destruction, but in this case, the protein knobs prevent that. Furthermore, the parasite occasionally changes the composition of these protein knobs. This makes it hard for the immune system to recognize it. This is the cause of the cyclical nature of the disease. Once the body learns to identify the protein knobs, it is able to dispatch the infected cells, and the disease goes into remission. Then the parasite changes the structure of the knobs, the body can no longer recognize it, and the parasite once again has free reign over the body. The parasite has another weapon in its arsenal. One of the by-products of the destruction of hemoglobin in red blood cells is hemozoin. When white blood cells are exposed to this compound, they become impaired, and the immune response they initiate in response is faulty. In particular, there is almost no antibody production. This not only makes it much harder for the body to fight off the malaria, but also makes it difficult to deal with any simultaneous infections. It also means that any vaccines given during the time of a malarial attack will be ineffective.
There are several anti-malarial drugs that can be prescribed to treat the disease. They are taken either orally or intravenously depending on the severity of the disease. Sometimes, these drugs can be taken before and during a trip to a malaria infested zone so as to assure that the traveler doesn't contract the disease. The parasites are becoming increasingly resistant to these medications. More research is needed to help prevent and treat this terrible disease that is still very much a threat to human health and happiness.