Fighting Disease

Understanding the Immune System

The immune system protects the body from potentially harmful substances like bacteria, viruses, and toxins.
It is comprised of various organs, cells, and proteins that work together to defend the body.
White blood cells (leukocytes), key players in the immune system, are produced in the bone marrow and patrol the body via the bloodstream, seeking out and destroying foreign invaders.

Innate and Adaptive Immune Responses

The immune response consists of the innate immunity and the adaptive immunity.
Innate immunity, the body’s first line of defence, includes physical barriers like skin and the cough reflex, and internal defences like inflammation and fever.
Adaptive immunity, the second line of defence, involves lymphocytes (B-cells and T-cells). This system is slower to react but has the ability to remember infectious agents, allowing a faster response if the same pathogen attacks again, a concept known as immunity.

How Diseases Fight the Immune System

Many diseases have evolved strategies to evade the immune system. For instance, some bacteria produce toxins that damage immune cells.
Viruses, another category of pathogens, can mutate rapidly, changing their surface proteins and making it difficult for the immune system to recognize and destroy them.

Disease Transmission

Understanding how diseases spread is key to preventing transmission.
Diseases can spread directly from person to person, via bodily fluids, droplets in the air from coughing or sneezing, or through direct skin-to-skin contact.
Diseases can also spread indirectly, for instance, when pathogens cling to objects such as door knobs or shared utensils.

Vaccinations

Vaccinations are a powerful tool in combating disease.
They work by introducing a harmless version of a pathogen into the body, triggering the immune system to produce a response.
This response typically involves the production of memory cells, which can recognise the pathogen in the future and respond quickly to prevent infection.

Antibiotics and Drug Resistance

Antibiotics are medications designed to fight bacterial infections. They work in various ways, including by killing bacteria directly or by preventing bacteria from reproducing.
Overuse or misuse of antibiotics can lead to the development of antibiotic-resistant strains of bacteria, a situation known as antibiotic resistance, which poses a serious challenge to global health.