Microorganisms and Diseases (GATE - XL)

GeneXpert testing system distinguishes fairly well between NTMs and mycobacterium tuberculosis. NTMs (non-tuberculous mycobacteria) are emerging microbes that cause a spectrum of diseases including TB-like lung disease, localised infections of the lymphatic system, skin, soft tissue or bone and systemic disease.

Histoplasma capsulatum fungus causes histoplasmosis. It is also known as Cave disease, Darling's disease or Ohio valley disease. The disease affects primarily the lungs and is common among AIDS patients due to their suppressed immunity.

Ehrlichiosis is an emerging bacterial disease in which obligate intracellular bacteria infect and kill white blood cells. It is caused by Anaplasma phagocytophilum, Ehrlichia ewingii, Ehrlichia chaffeensis or Neorickettsia sennetsu.

Enterovirus 71 causes polio-like syndrome or permanent paralysis. This virus appears to have evolved only recently with the first known strain isolated in 1965.

Typhoid Mary was a chronic carrier and was presumed to have infected 51 people, three of whom died. She harboured the pathogen inside her body for a long time.

The causative organism for 1918-1919 pandemic was influenza virus. It took 20 million lives.

In herd immunity, only some of the inhabitants are immunised and others develop immunity themselves. It is a form of indirect protection from infectious diseases that occurs when a large percentage of population has become immune to an infection. It provides a measure of protection for individuals who are not immune.

Aspergillus parasiticus secretes aflatoxins. It is frequently found in tree nuts, peanuts, maize, sorghum and other oilseeds, including corn and cottonseeds. 

Racial immunity is when different races within a species show differences in susceptibility to infections. In some parts of Africa, resistance to Plasmodium falciparum malaria is an example of racial immunity.

Racial immunity is a natural immunity shared by most of the members of a genetically related population. In humans, it is explained through selectivity and survival.

In little girls, vulvovaginitis is acquired through fomites. Bedclothes, towel and common bath tubs may spread the infection.

Transferrins are found in serum. These are proteins with antibacterial activity and are iron-binding blood plasma glycoproteins that control the level of free iron in biological fluids. 

Campylobacter jejuni is recognised as one of the main causes of bacterial food-borne disease in many developed countries. This pathogen can be the underlying cause of secondary Guillain-Barré syndrome and periodontitis.

Leptospira causes leptospirosis. It may not be always water-borne. It causes a non-intestinal disease where bacteremia and kidney damage takes place.

A person who had a disease and has recovered from it will act as a convalescent carrier. It is because he is still capable of transmitting the infectious agent to others.