How The Human body Fought Sickle Cell Disease With Another Disease

Malaria and sickle cell disease have a long history together. It is thought that the sickle cell trait is acquired as a result of the efforts-natural selection – made by the human body to combat malaria.

The current frequency of malaria in endemic areas is thought to indicate selection for the sickle cell trait carrier type due to a survival advantage. Malaria has been linked to a high mortality rate in sickle cell disease patients (SCD).

Malaria is endemic to regions with certain climatic conditions where the causative agent thrives. Coincidentally, the sickle cell trait is also highly prevalent in these regions. Suggesting that there is a relationship between both diseases.

What is the main cause of sickle cell anaemia?

Sickle Cell Anaemia, also called Sickle Cell Disease, is a genetic disease. It is caused by a genetic mutation in one of the genes responsible for formulating the haemoglobin in the red blood cell.

Red blood cells are disc-shaped cells responsible for carrying oxygen in the blood to tissues and organs. When these red blood cells become sickle as a result of genetic mutation, they become disfigured and sticky.

The mutation of the Hemoglobin gene causes the red blood cells to stick to the walls of surrounding blood vessels leading to an obstruction of blood flow to other parts of the body.

Eventually, tissue damage and pain occur as a result of a lack of oxygenated blood supply. Noteworthy, Sickle cell disease is a genetic disease that requires two copies of the defective gene to have the disease.

However, it is possible to acquire one of the genes, this is not enough to acquire sickle cell disease.

If you have two copies of the gene then you have the disease. While, if you have just a copy of the gene then you are called a ‘sickle cell carrier’.

Types of sickle cell disease

Blood vessel showing sickle cell disease
Sickled Red Blood Cell

Haemoglobin is the oxygen-carrying protein in red blood cells. It usually consists of two alpha and two beta chains. Different mutations in these genes produce the four main forms of sickle cell anaemia.

  • Haemoglobin SS disease
  • Haemoglobin SC disease
  • Haemoglobin SB+ thalassemia
  • Hemoglobin SB 0 (Beta -zero) thalassemia

Haemoglobin SS disease

The most frequent kind of sickle cell illness is haemoglobin SS disease. It happens when both parents give you copies of the haemoglobin S gene. This results in Hb SS haemoglobin. Individuals with the most severe type of SCD also suffer the most severe symptoms at a greater rate.

Haemoglobin SC disease

The second most frequent kind of sickle cell disease is haemoglobin SC illness. When you receive the Hb C gene from one parent and the Hb S gene from the other, you have this condition. Hb SC patients experience symptoms that are comparable to Hb SS patients. The anaemia, on the other hand, is not as severe.

Haemoglobin SB+ thalassemia

The generation of beta-globin genes is affected by haemoglobin SB+ (beta) thalassemia. Because less beta protein is produced, the size of the red blood cell shrinks. Haemoglobin S beta-thalassemia is caused by inheriting the Hb S gene. The symptoms aren’t as bad.

Hemoglobin SB 0 (Beta -zero) thalassemia

The fourth kind of sickle cell illness is sickle beta-zero thalassemia. The beta-globin gene is also involved. It displays symptoms that are comparable to Hb SS anaemia. The symptoms of beta zero thalassemias can, however, be more severe at times.

Aside from these variants of Sickle cell disease, there exist other three types that are rare and unlikely to exhibit any symptoms.

  • Haemoglobin SD
  • Hemoglobin SE
  • Haemoglobin SO

Sickle cell carriers

People who have inherited just one mutated gene i.e. haemoglobin S of one parent are usually called sickle cell carriers. Carriers usually do not exhibit symptoms of the disease but there are reported mild cases.

Why Does Sickle cell affect only Africans?

sickle cell disease
African Boy

Africa is a large continent with diverse topographical and climatic conditions. Albeit a large part of Africa is plagued by the disease, not all Africa is affected by it. Also, countries with similar climatic conditions as Africa are also prone to the disease.

America, the sub-Indian continent, and the Mediterranean are also countries with a high prevalence of the disease.

The disease is particularly prevalent in Sub-Saharan Africa, where up to 45 percent of the population is infected. Because being a carrier provides a survival benefit against malaria, it has spread so widely there.

Malaria isn’t a major concern in the Middle East, and the general rate of sickle-cell disease carriers is low. However, this isn’t the case everywhere; in some places, the number of carriers is alarmingly large. In some places of Saudi Arabia, for example, the carrier rate is as high as 27%.

But is Sickle cell disease a result of climatic conditions?

Absolutely not. However, climatic conditions that favor mosquito breeding grounds are more likely to be carriers of the disease. Therefore regions with endemic malaria are the affected demographic.

Regions that fall affected due to endemic malaria include;

  • Africa
  • Asia
  • Middle East
  • Mediterranean
  • South America

What’s the Relationship between Malaria and SCDs

sickle cell disease
Mosquito

Malaria is a deadly disease caused by a parasitic infection of the blood. Malaria is a sickness that can kill you. The disease is spread by the bite of an infected Anopheles mosquito. The Plasmodium parasite is carried by infected mosquitoes.

The parasite is delivered into your circulation when this mosquito bites you.

Once inside your body, parasites make their way to your liver, where they mature. The mature parasites enter the bloodstream and begin infecting red blood cells after several days.

It is no coincidence that the blood cell affected by malaria is also the blood cell affected by SCD.

Malaria Endemic Areas and Hemoglobin gene mutations

We have already established that malaria’s distribution is subject to climatic influence. Regions with more Malaria infections are mostly tropical zones with weather conditions that favour the multiplication of the vector, i.e., Anopheles mosquito.

Scientists have observed that regions that are most affected by the malaria disease also have a correlating high amount of sickle cell traits among people.

  • Malaria is a disease associated with the red blood cells of humans. Plasmodium, the causative agent, infects the red blood cells, eventually causing its destruction.
  • Sickle cell disease, on the other hand, is a disease of the red blood cell. Unlike Malaria, it is not caused by an infective agent. rather, SCDs arise as a result of genetic mutation of the gene that promotes the development of haemoglobin in the red blood cells.

Noticeably, when a person carrying the sickle cell trait is infected with Plasmodium(the causative agent for malaria) it was discovered that the pathogen infection rate was less.

In other words, there is a higher prevalence of malaria in people without the mutated sickle cell gene than there is with carriers of the mutated gene.

Scientists have suggested that the hemoglobin gene mutation must have been an evolutionary response to the high prevalence of the deadly malaria disease.

Sickle cell anaemia, according to scientists, is in fact supposed to be a resistive measure against the infection of the parasite causing malaria.

Advantages of Sickle cell trait

The distorted shape of the red blood cell confers several defensive mechanisms against Plasmodium.

  • The distorted shape of the red blood cell of a sickle cell disease patient prevents plasmodium from entering the blood cells, preventing the parasite’s proliferation in the bloodstream.
  • A mutated red blood cell is usually destroyed by the immune system. Technically, this reduces the number of available cells to the parasite, which can only survive in the red blood cell.
  • In summary, Sickle cell prevents the malaria-causing parasites from finding suitable resting spots in the blood consequently, reducing the parasitic load in the patient.

Can you get malaria with sickle cell anaemia?

Patients with SCD are also more susceptible to serious infections, such as malaria. This is especially noteworthy because SCD’s geographic distribution is quite similar to that of malaria, with both disorders being common throughout Africa’s tropical belt, including Tanzania.

This coincidental epidemiology is not coincidental: data suggests that heterozygotes for the sickle gene (Hb genotype AS) are less likely to die from malaria, owing to a faster clearance of Plasmodium falciparum-infected erythrocytes by macrophages. Patients with homozygous (Hb SS) SCD, on the other hand, have a higher risk of dying from malaria.

If Sickle Cell Disease is an Advantage Then Why is it Deadly?

SCDs are only deadly when an individual possesses both mutated genes of the disease. Although SCDs confer an advantage, they may be disadvantages of having the disease.

Red blood cells are components of the blood responsible for transporting oxygen throughout the body.  When there is a shortage of red blood cells in the body, the organs and tissues are starved of oxygen leading to tissue death.

SCDs significantly reduce the number of red blood cells in the bloodstream leading to a blood-deprived type of symptoms.

Also sickle cells in the blood which are produced as a result of gene mutation frequently block blood channels also starving various parts of the body of nutrients and oxygen. Consequently, the blood-deprived parts start to die.

Does Sickle cell cause pain?

Boy In Pain

SCD can lead to serious problems, which occur when sickle cells block blood arteries in various parts of the body. Sickle cell crises are painful or harmful obstructions. Severe complications can arise from sickle cell anaemia: 

 1.  Anemia

Anaemia is a disorder in which your body’s tissues don’t get enough oxygen because you don’t have enough healthy red blood cells. Anaemia, commonly known as low haemoglobin, can leave you feeling exhausted and weak.

Anaemia comes in a variety of types, each with its unique aetiology. Anaemia can be short-term or long-term, and it can be mild or severe. Anaemia is caused by a variety of factors in the majority of cases.

2.  Hand-foot syndrome

Sickle-shaped RBCs restrict blood arteries in the hands and feet, causing the hand-foot syndrome. The hands and feet swell as a result of this. It may also result in leg ulcers. In newborns, swollen hands and feet are frequently the first sign of sickle cell anaemia.

3.  Delayed growth

People with SCD frequently experience delayed growth. Children are often shorter, but by adulthood, they have regained their height. Sexual maturation may be postponed as well. This occurs because sickle cell RBCs are unable to provide sufficient oxygen and nutrients.

4.  Nerve system disruption

Sickle cell illness can cause seizures, strokes, and even coma. They are caused by obstructions in the brain. Treatment should be sought right away.

5.  Defective eyesight

Blockages in the vessels supplying the eyes induce blindness. The retina may be harmed since healthy RBC can’t reach it.

6.  Ulcers(skin and foot ulcers)

When the blood supply to the foot is interrupted, the legs may develop a skin ulcer.

7.   Failed Lungs

Increased blood pressure in the lungs (pulmonary hypertension) and scarring of the lungs can occur as a result of damage to the lungs caused by decreased blood flow over time (pulmonary fibrosis).

Patients with sickle cell disease may experience these issues sooner. Lung damage makes it more difficult for the lungs to transmit oxygen into the blood, making sickle cell crises more common.

When do babies show signs of sickle cell?

SCD patients produce an abnormal kind of haemoglobin. This is the protein found in red blood cells that transports oxygen throughout the body.

Symptoms in most children with SCD appear in the first year of life, usually around the age of five months. Symptoms differ from child to child. They might range from minor to severe.

Can Sickle cell anaemia be cured?

As of the moment, there is no definitive cure for the disease. It can however be managed. When managed properly, the patient may live a normal life.

The goal of sickle cell anaemia treatment is to minimize pain episodes, relieve symptoms, and prevent consequences. Medications and blood transfusions may be used as treatments. A stem cell transplant may be able to treat the condition in certain children and teenagers.

Difference between Sickle Cell disease and anaemia

Sickle cell anaemia is an inherited red blood cell condition in which the body’s supply of healthy red blood cells is insufficient to transport oxygen throughout the body, While Anemia is a disorder in which your body’s tissues don’t get enough oxygen because you don’t have enough healthy red blood cells.

Anaemia, commonly known as low haemoglobin, can leave you feeling exhausted and weak. Anaemia comes in a variety of types, each with its unique aetiology.

Anaemia is the major symptom associated with SCD.

Can you live a long life with sickle cell anaemia?

This would depend on the kind of livelihood of the patient. However, studies suggest that people with SCD have a lower life span compared to people without the disease. In the study, the projected life expectancy for people with SCD was 54 years.

People with the disease suffer from a series of illnesses and eventually suffer organ failure as they age. All these are contributing factors to the short life span experienced by SCD patients.

Patients must thoroughly follow the laid out management plan by their doctors in order to extend their lifespan.  In the absence of medication and other preventive measures, patients may die before reaching adulthood.

What ethnicity is prone to sickle cell disease?

Numerous studies have demonstrated that sickle cell anaemia affects people of African descent the most. This is probably because the disease originated from Africa and did not develop independently as previously thought.

Africa also has the highest prevalence of Malaria. It makes sense that people of African descent are more prone to the disease than other ethnic groups.

Nonetheless, no ethnic group is left out. Whites, Asians, South Americans, and people of the middle east also suffer from the disease. The disease has been observed to be less prevalent in whites.

What gender is most affected by sickle cell anaemia?

Sickle cell anaemia is an autosomal disease, this means it is not passed down to offspring based on sex. Neither is it linked to sex. Both gender or sexes has the same level of risk of contracting the disease.

The disease is not transmitted from parent to offspring, rather children inherit the defective gene from parents; either both mutated genes or a single mutated gene.

Some studies show a disproportionate amount of episodes in men than in women. Scientists are not totally sure why this occurs but they attribute it to the difference in hormones.

What should sickle cell patients avoid?

Living with sickle cell is a difficult task. you would be exempted from a lot of activities and have to take medications frequently. here are some helpful tips to living with the disease;

  • Drink plenty of water, especially if it’s hot outside, as dehydration can lead to a sickle cell crisis.
  • Avoid severe temperatures — dress correctly for the weather and avoid drastic temperature fluctuations, such as swimming in freezing water.
  • At high elevations, be cautious because a lack of oxygen might precipitate a crisis (traveling by plane should not be a problem because planes are pressured to maintain a steady oxygen level).
  • Avoid severe exercise – People with sickle cell disease should stay active, but vigorous activities that leave you gasping for air should be avoided.
  • Avoid consuming alcohol and smoking, as both can dehydrate you, and smoking can induce acute chest syndrome, a dangerous lung ailment.
  • It’s also a good idea to be ready at home to address painful occurrences. Keep pain relievers on hand, and consider purchasing heated pads to help with the discomfort.

Does sickle cell worsen with age?

As patients with SCD live longer, more older persons will require treatments and care. Because there are few clinicians with experience managing SCD problems, providing care for elderly persons is difficult.

At least one organ has been permanently damaged in half of SCD patients over the age of 50. In elderly persons, pain crises and complications are more common.

Stress, eyesight loss, bone health, discomfort, and other long-term problems must all be monitored on a regular basis.

Can sickle cell patients get pregnant?

Women with SCD who wish to start a family should talk to their doctor about how to prepare for pregnancy and limit the risk of complications. Women with SCD may require special attention during pregnancy in order to keep themselves and their babies healthy.

Supposing an AS person is marrying another with AS or AS marrying one with SS is the couple in question.

that is;

  • AS + AS
  • or AS + SS

The first pair has a 25% probability of having a healthy non-carrier (AA), a 50% chance of having a good carrier (AS), and a 25% risk of having a sickler (SS).

The second pair has a 50/50 probability of having a healthy carrier (AS) or a sickler as a child (SS). The term “chance” refers to the probability that a pregnant woman will give birth to any of the babies listed above.

It is strongly advised that a person with SS should not marry another with SS.

The Wrap-Up!

While people with a single trait for sickle cell anaemia may enjoy some resistance against malaria, those with both genes suffer for a long period of time.

Sickle cell anaemia, also call Sickle cell disease is acquired when a child is born with both genes of the sickle cell.  Malaria is a disease prevalent in regions where SCD is also of high prevalence.

This suggests a relationship between both and was discovered that the single trait of the sickle cell confers an advantage in the prevention of malaria.

There is no cure for Sickle cell disease, however, it can be managed. People with the disease may experience symptoms from an early age in childhood and may have a shortened life span.

People with SCD have to make adjustments in their livelihood to manage the disease, as the disease has no cure.

Sickle cell disease (SCD) affects millions of people around the world, with a high prevalence in sub-Saharan Africans, Spanish-speaking regions in the Western Hemisphere, Saudi Arabia, India, and Mediterranean countries like Turkey, Greece, and Italy.