Question

Which of the following is not a viral disease?
A. Measles
B. Rabies
C. Polio
D. Tuberculosis

Answer 1

Hint: this is a common disease, typically associated with the lungs but no rash occurs in this illness.

Complete answer:
Tuberculosis is an infectious disease caused by a small, aerobic, non motile bacillus, known as the Mycobacterium tuberculosis (MTB). It can withstand weak disinfectants and survive in a dry state for weeks. In nature, the bacterium can grow only within the cells of a host organism, but it can also be cultured in a laboratory.
It usually affects the lungs (called pulmonary tuberculosis), but can also spread to other parts of the body, like the brain and the spine (extrapulmonary tuberculosis).
The infection sites of extrapulmonary tuberculosis include the pleura (in tuberculous pleurisy), the central nervous system (in tuberculous meningitis), the lymphatic system (in scrofula of the neck), the genitourinary system (in urogenital tuberculosis), and the bones and joints (in Pott disease of the spine), among others. A potentially more serious, widespread form of TB is called "disseminated tuberculosis", which is also known as military tuberculosis.

Symptoms of Pulmonary tuberculosis :
- May include chest pain and a prolonged cough producing sputum.
- May cough up blood in small amounts, and in very rare cases, the infection may erode into the pulmonary artery or a Rasmussen's aneurysm, resulting in massive bleeding.
- May become a chronic illness and cause extensive scarring in the upper lobes of the lungs. The upper lung lobes are more frequently affected by tuberculosis than the lower ones.

There are two forms of this disease:
> Latent TB:
The pathogens are there in the body, but the immune system keeps them from spreading. No symptoms show, and it is not contagious. However, the infection is still alive and can one day become active. Also, the host is at high risk for activation or reactivation if, for instance, they have HIV, have had an infection in the past 2 years, chest X-ray is unusual, or if the immune system is weakened.
> Active TB:
The pathogens multiply and make the host sick. It is now contagious. About 90% of active cases in adults come from a latent TB infection.

Additional Information:
- Measles is a highly contagious, airborne disease caused by the measles virus, which is a single-stranded, negative-sense, enveloped RNA virus of the genus Morbillivirus within the family Paramyxoviridae. The symptoms include a four-day fever, cough, coryza (head cold, fever, sneezing), and conjunctivitis (red eyes), along with a maculopapular rash.
- Rabies is a viral disease caused by the lyssaviruses, including the rabies virus and Australian bat lyssavirus. It spreads when an infected animal bites or scratches a human or other mammals. Saliva from an infected animal can also transmit rabies if the saliva comes into contact with the eyes, mouth, or nose. It causes inflammation of the brain in humans and other mammals.
- Polio, short for poliomyelitis, is an infectious disease caused by the poliovirus. This disease causes muscle weakness resulting in an inability to move.

So, the correct answer is Tuberculosis.

Note:
- A viral disease (or viral infection, or infectious disease) occurs when an organism's body is invaded by pathogenic viruses, and infectious virus particles (virions) attach to and enter susceptible cells.
- DNA viruses replicate within the cell nucleus while RNA viruses replicate within the cytoplasm. Exceptions are known to this rule: poxviruses replicate within the cytoplasm and orthomyxoviruses and hepatitis D virus (RNA viruses) replicate within the nucleus.