Topic : Diseases Conducted By : Renuguntla Suresh

Explanation
The common cold is a viral disease caused by various types of viruses, such as rhinoviruses. It is highly contagious and spreads easily from person to person through respiratory droplets. Symptoms of the common cold include a runny or stuffy nose, sore throat, cough, and mild fever. Unlike malaria, filaria, and syphilis, which are caused by parasites or bacteria, the common cold is caused by a viral infection.

Explanation
Tuberculosis is caused by bacteria. This infectious disease is primarily caused by Mycobacterium tuberculosis, a type of bacteria that mainly affects the lungs but can also target other parts of the body. The bacteria spread through the air when an infected person coughs, sneezes, or talks, and can be inhaled by others. The bacteria then invade the lungs and multiply, leading to the development of tuberculosis. Treatment typically involves a combination of antibiotics to kill the bacteria and prevent the spread of the disease.

Explanation
All of the given options, malaria, filaria, and dengue, are insectborne diseases. Insectborne diseases are transmitted to humans through the bites of infected insects, such as mosquitoes. Malaria is caused by the Plasmodium parasite, which is transmitted by infected female Anopheles mosquitoes. Filaria is caused by parasitic worms transmitted through the bites of infected mosquitoes. Dengue is caused by the dengue virus, which is transmitted by the Aedes mosquito. Therefore, all of these diseases are classified as insectborne.

Explanation
The target cell of the polio virus is the nerve cell. Polio is a viral infection that primarily affects the nervous system, specifically the motor neurons in the spinal cord and brainstem. The virus enters the body through the mouth and multiplies in the intestines, from where it can spread to the bloodstream and eventually reach the nervous system. Once inside the nerve cells, the virus replicates and causes damage, leading to paralysis and other neurological symptoms associated with polio.

Explanation
The Widal test is used for the diagnosis of typhoid. This test detects antibodies in the blood that are produced in response to the Salmonella typhi bacteria, which causes typhoid fever. By measuring the levels of these antibodies, the Widal test helps in confirming the presence of typhoid infection in a patient. The test is based on the principle of agglutination, where the antibodies cause clumping of the bacteria or their components. This clumping reaction can be observed and measured to determine the diagnosis of typhoid.

Explanation
HIV targets white blood cells (WBC) because these cells play a crucial role in the immune system's response to infections. HIV specifically targets CD4+ T cells, a type of white blood cell that helps coordinate the immune response. By infecting and destroying these cells, HIV weakens the immune system, making the individual more susceptible to infections and diseases.

Explanation
The BCG vaccine is used to prevent tuberculosis (TB). It is a vaccine that helps protect against the bacteria that causes TB. TB is a highly contagious disease that primarily affects the lungs but can also spread to other parts of the body. The BCG vaccine stimulates the immune system to recognize and fight off the TB bacteria, reducing the risk of infection and the development of active TB disease. It is commonly given to infants and children in countries with a high prevalence of TB.

Explanation
All of the options listed (AIDS, Hepatitis, Syphilis) are sexually transmitted diseases. AIDS is caused by the human immunodeficiency virus (HIV) and can be transmitted through sexual contact. Hepatitis can also be transmitted sexually, with hepatitis B and C being the most common types transmitted in this way. Syphilis is a bacterial infection that is primarily transmitted through sexual contact. Therefore, all of the options listed are correct answers as they are sexually transmitted diseases.

Explanation
Tetanus is a soil borne disease because it is caused by the bacterium Clostridium tetani, which is commonly found in soil, dust, and manure. The bacteria can enter the body through cuts, wounds, or puncture injuries, and produce a toxin that affects the nervous system, leading to muscle stiffness and spasms. This disease is particularly associated with contaminated soil, making it a soil borne disease.

Explanation
ELISA test is commonly used for the diagnosis of AIDS. ELISA stands for Enzyme-Linked Immunosorbent Assay and it is a highly sensitive and specific test that detects antibodies or antigens in the blood. In the case of AIDS, the ELISA test detects the presence of antibodies against the Human Immunodeficiency Virus (HIV). This test is crucial for the early detection and diagnosis of AIDS, allowing for timely medical intervention and appropriate management of the disease.