A true pilonidal sinus in the hand of a sheep shearer. 2) Uncommonly, the cyst may become secondarily infected, resulting in osteomyelitis with formation of an abscess and draining sinus to the overlying skin. Echinococcal disease of the bone: an unusual cause of a pathological fracture.
Tobacco mosaic virus (TMV) is a positive-sense single stranded RNA virus that infects a wide range of plants, especially tobacco and other members of the family Solanaceae.The infection causes characteristic patterns, such as  mosaic -like mottling and discoloration on the leaves (hence the name).TMV was the first virus ever to be discovered.Although it was known from the late 19th century that an infectious disease was damaging tobacco crops, it was not until 1930 that the infectious agent was determined to be a virus.he infection causes characteristic patterns, such as  mosaic -like mottling and discoloration on the leaves (hence the name). TMV was the first virus ever to be discovered.
Trypanosomiasis, also known as African sleeping sickness, is an infection endemic to sub-Saharan Africa. It is caused by protozoan parasites called trypanosomes, which are spread by the bite of the tsetse fly.There are two subspecies of trypanosomes that infect humans, each causing a different form of the disease.rypanosomiasis (trÉpÄnÂ´ÉsÅmÄ«Â´Ésis) , infectious disease caused by a protozoan organism, the trypanosome, which exists as a parasite in the blood of a number of vertebrate hosts. The three variations of the disease that predominate in humans are transmitted by an insect vector.