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.
Serratia marcescens is another facultative pathogen of insects, causing septicemia. The non-spore-forming bacterium, Melissococcus pluton, is the causal agent of European foulbrood in honeybees. The bacteria group also includes the Rickettsia, some species of which are pathogenic (particularly the Rickettsiella).ost of the non-spore-forming species of bacteria isolated from insects are in the families Enterobacteriaceae or Pseudomonidaceae. Non-spore-forming bacteria generally have low pathogenicity when they occur in the digestive tract of an insect, but may be very pathogenic if they are able to enter the insect's hemocoel.