Biology — Diseases & Immunity

Malaria is caused by Plasmodium parasites, which are transmitted to humans through the bites of infected female Anopheles mosquitoes.

ELISA (Enzyme-Linked Immunosorbent Assay) is a plate-based assay technique designed for detecting and quantifying substances such as peptides, proteins, antibodies, and hormones, most famously used to screen for HIV.

Pellagra is a disease caused by a severe deficiency of Vitamin B3 (Niacin). It is characterized by the 'four Ds': dermatitis, diarrhea, dementia, and death.

The BCG vaccine is primarily used against tuberculosis (TB), which is caused by the bacterium Mycobacterium tuberculosis.

White blood cells (Leukocytes) are the cells of the immune system that protect the body against both infectious disease and foreign invaders.

Typhoid fever is a systemic infection caused by the bacterium Salmonella enterica serotype Typhi, typically spread through contaminated food or water.

Jaundice is a condition characterized by yellowing of the skin and eyes, caused by an excess of bilirubin, which reflects a dysfunction or disease of the liver.

Autoimmunity occurs when the immune system loses its ability to distinguish 'self' from 'non-self' and starts attacking the body's own healthy tissues.

Dengue fever is often called 'breakbone fever' because it causes intense joint and muscle pain, making the patient feel as if their bones are breaking.

African trypanosomiasis, or sleeping sickness, is caused by microscopic parasites of the species Trypanosoma brucei, transmitted by the Tsetse fly.

Cholera is an infectious disease that causes severe watery diarrhea, which can lead to dehydration and even death if untreated. It is caused by eating food or drinking water contaminated with the bacterium Vibrio cholerae.

B-lymphocytes (B-cells) are the immune cells responsible for producing antibodies, which specifically recognize and bind to antigens to neutralize pathogens.

Itai-itai disease was the documented case of mass cadmium poisoning in Toyama Prefecture, Japan, starting around 1912. The name refers to the severe pain in the spine and joints.

The spleen acts as a blood filter and removes old or damaged red blood cells from the circulation, earning it the title of 'Graveyard of RBCs'.

Kala-azar (Visceral Leishmaniasis) is caused by the parasite Leishmania donovani and is transmitted to humans through the bite of an infected female sandfly.

Active natural immunity develops when the body is exposed to a live pathogen, recovers from the disease, and develops antibodies and memory cells to prevent future infections.

Hepatitis B is transmitted through contact with infectious blood, semen, and other body fluids, commonly via needles, unprotected sex, or from mother to child at birth.

Goitre is an enlargement of the thyroid gland, which is most commonly caused by a deficiency of iodine in the diet.

Interferons are signaling proteins released by host cells in response to the presence of several viruses. They interfere with viral replication by signaling neighboring cells to heighten their anti-viral defenses.

Leprosy, also known as Hansen's disease, is a chronic infectious disease caused by Mycobacterium leprae that primarily affects the skin, nerves, and mucous membranes.

Rabies is a zoonotic viral disease transmitted through the saliva of infected animals, most commonly dogs.

C-reactive protein (CRP) is produced by the liver and its levels rise in response to inflammation.

HIV specifically targets and destroys CD4+ Helper T-cells, which are essential for coordinating the immune response.

Xerophthalmia is a progressive eye disease caused by a severe deficiency of Vitamin A.

Yersinia pestis is a gram-negative bacterium that causes plague and is typically transmitted by fleas on rodents.

Passive immunity involves receiving antibodies rather than producing them, such as antibodies passed from mother to infant via the placenta or breast milk.

The Widal test detects the presence of agglutinating antibodies against Salmonella typhi, the causative agent of Typhoid.

Botulinum toxin blocks nerve function, specifically targeting the neuromuscular junction, leading to paralysis.

Anthracosis is a lung disease caused by the inhalation of coal dust particles.

The Aedes aegypti mosquito is the primary vector for Zika, Dengue, and Chikungunya viruses.

Meningitis is the inflammation of the meninges, the protective membranes covering the brain and spinal cord.

Memory B and T cells persist after an infection or vaccination, allowing the immune system to respond rapidly upon reinfection.

Pellagra is a disease caused by a severe lack of vitamin B3 (niacin) in the diet, historically characterized by the four Ds: diarrhea, dermatitis, dementia, and death.

Tetanus is often called 'lockjaw' because one of the most common signs of the infection is muscle spasms in the jaw.

Ringworm is a contagious fungal infection caused by dermatophytes, not a parasitic worm as the name suggests.

Lysozymes are enzymes found in saliva, tears, and mucus that kill bacteria by breaking down their cell walls.

Rheumatoid arthritis occurs when the immune system mistakenly attacks the joints, causing chronic inflammation.

Jonas Salk developed the Inactivated Polio Vaccine (IPV), which uses dead virus particles.

Minamata disease is caused by methylmercury poisoning, which affects the central nervous system.

Malaria is caused by various species of the protozoan parasite Plasmodium.

Hemophilia is a genetic disorder where blood does not clot properly due to a deficiency in clotting factors, primarily affecting males.

DOTS is the internationally recommended strategy for TB control, ensuring patients complete their medication course.

Influenza, commonly known as the flu, is a contagious respiratory illness caused by influenza viruses.

Insulin regulates blood glucose; its deficiency leads to high blood sugar levels, characteristic of Diabetes Mellitus.

Vaccination introduces antigens into the body, stimulating the immune system to produce memory cells and antibodies (active immunity).

Cystic Fibrosis is a genetic disorder that affects the cells that produce mucus, sweat, and digestive juices, leading to severe blockages.

Cholera is caused by Vibrio cholerae and is characterized by profuse watery diarrhea and dehydration, but typically does not cause high fever.

HIV targets CD4+ T-helper cells, which are crucial for coordinating the body's overall immune response.

Vitamin B12 is essential for red blood cell formation; its deficiency leads to megaloblastic or pernicious anemia.

Thrombocytes, or platelets, are cell fragments that aggregate at injury sites to form a clot (hemostasis).