Progressive vaccinia is a rare cutaneous condition caused by the vaccinia virus, characterized by painless, but progressive, necrosis and ulceration.[4]
Opportunistic fungal, protozoal, or bacterial infections and the vaccinia virus itself may lead to septic shock and disseminated intravascular coagulation, in addition to necrosis and ulcerated skin tissue. Some of these tissues may eventually become large, requiring not only a skin graft but surgical removal of the destroyed tissue, in order to avoid graft-versus-host disease in organ transplanted patients, in whom immunosuppressive therapy would otherwise have to be discontinued to allow healing of the wound.[citation needed]
Vaccinia is introduced into the skin by means of multiple punctures of a bifurcated needle. The virus replicates in the basal layer and disseminates from cell to cell, causing necrosis and the formation of fluid-filled vesicles. Nonetheless, the initial spread of the virus is slowed by innate antiviral mechanisms, and, by the second week, the cell-mediated immune response begins to eliminate infected cells[a]. Neutrophils, macrophages, and lymphocytes infiltrate the inoculation site, forming a confluent pustule and releasing cytokines and chemokines that cause hyperemia and edema in surrounding tissues. This may initially manifest into complaints of malaise and other mild constitutional symptoms, fever, vomiting, and tender enlarged axillary lymph nodes. Some vaccinees develop additional local “satellite” pustules that resolve along with the primary lesion.[citation needed]
The virus may gain access to the blood at an early stage, and secondary skin lesions, which follow the same evolution as the inoculation site, may appear across the body. Bacteria, like Staphylococcus aureus, may infect the ulcerated, and necrotic lesions. Coalescent lesions may cover large portions of the body with extensive tissue destruction. Although some vaccinia viruses commonly disseminate through the bloodstream, the NYCBOH strain reportedly causes only limited viremia in a small percentage of recipients during the period of pustule formation.[6][7] The inflammatory process reaches its peak by days 10–12 after vaccination and begins to resolve by day 14, with the shedding of the scab and other pustules by day 21. This sequence of events, which simulates the development of smallpox "pock", is known as a “take” reaction. A successful "take" is required for the development of antivaccinia antibody and cell-mediated responses.[8][9][10][11]
| Progressive vaccinia | |
|---|---|
| Other names | Vaccinia gangrenosum, Vaccinia necrosum or disseminated vaccinia |
 | |
| The patient required a skin graft on her upper left arm in order to correct the necrotic vaccination site, due to the onset of progressive vaccinia, formerly known as vaccinia gangrenosum. | |
| Specialty | Dermatology |
| Symptoms | Malaise, fever, vomiting and tender, enlarged axillary lymph nodes; progresses to septic Pseudomonas aeruginosa, likely from a perirectal abscess, Clostridium difficile (bacteria), Staphylococcus aureus and cell-mediated immunodeficiency. |
| Complications | Necrosis of the injected part, exacerbating to gangrene and eventual amputation. Usually, the pocks tend to go away without scarring; however, the external and internal spread of the virus may have serious consequences in persons with eczema and other forms of atopic dermatitis, in these persons, defects of innate immunity and a high level of Th2 cell activity render the skin unusually permissive to the initiation and rapid spread of vaccinia infection (known as “eczema vaccinatum”)[1][2] |
| Usual onset | 11 days to 6.5 weeks |
| Duration | Long-lasting |
| Causes | Injection by the vaccinia virus(genus: orthopoxvirus) as a countermeasure for smallpox[3] |
| Risk factors | People with cellular immunodeficiencies |
| Diagnostic method | Fever and headache, then progressive ulceration and necrosis of the injection site for smallpox, albeit the lack of inflammation is noted as the "hallmark of PV"[3] |
| Differential diagnosis | May initially be mistaken for leukemia |
| Prevention | Unknown |
| Treatment | Vaccinia Immune Globulin Intravenous (Human) (VIGIV), Emergency Investigational New Drug (E-IND) both administered orally and topically, (in this case ST-246); CMX001, a lipid conjugate of cidofovir and granulocyte colony-stimulating factor for the exiguous normal white blood cells;supportive care; skin graft |
| Medication | Imiquimod, and thiosemicarbazone |
| Prognosis | Lifelong |
| Frequency | every 1 or 2 in a million during routine vaccination during 1963-1968 for smallpox |
| Deaths | fatality rate: 15% |
See also[edit]
- Vaccinia
- Skin lesion
- Necrosis
- Smallpox
- Vaccination
- Chicken pox
- Cowpox- a virus closely related to the vaccinia virus and belongs to the same genus Orthopoxvirus.
Note[edit]
- ^ Immunosuppressed individuals tend to have a larger fatality rate and tendency to get the virus due to HIV infection, iatrogenic immunosuppression, etc. Although these conditions are contraindications to the dermovaccine, inadvertent inoculation after contact with a vaccinee may occur; in layman's terms, inoculation means the introduction of a pathogen or antigen into a living organism to stimulate the production of antibodies.[5] Due to the impaired immune response of the host, the virus multiplies by cell-to-cell spread at the inoculation site, and the lesion expands circumferentially, forming the trademark symptoms called "pocks".
https://en.wikipedia.org/wiki/Progressive_vaccinia
Generalized vaccinia is a cutaneous condition that occurs 6–9 days after vaccination, characterized by a generalized eruption of skin lesions, and caused by the vaccinia virus.[1]:391
See also[edit]
References[edit]
- ^ James, William D.; Berger, Timothy G.; et al. (2006). Andrews' Diseases of the Skin: clinical Dermatology. Saunders Elsevier. ISBN 0-7216-2921-0.
https://en.wikipedia.org/wiki/Generalized_vaccinia
Vaccinia virus (VACV or VV) is a large, complex, enveloped virus belonging to the poxvirus family.[2] It has a linear, double-stranded DNA genome approximately 190 kbp in length, which encodes approximately 250 genes. The dimensions of the virion are roughly 360 × 270 × 250 nm, with a mass of approximately 5–10 fg.[3]The vaccinia virus is the source of the modern smallpox vaccine, which the World Health Organisation used to eradicate smallpox in a global vaccination campaign in 1958–1977. Although smallpox no longer exists in the wild, vaccinia virus is still studied widely by scientists as a tool for gene therapy and genetic engineering.
Smallpox had been an endemic human disease that had a 30% fatality rate. In 1796, the British doctor Edward Jenner proved that an infection with the relatively mild cowpox virus would also confer immunity to the deadly smallpox. Jenner referred to cowpox as variolae vaccinae (smallpox of the cow). However, the origins of the smallpox vaccine became murky over time,[4] especially after Louis Pasteur developed laboratory techniques for creating vaccines in the 19th century. Allan Watt Downie demonstrated in 1939 that the modern smallpox vaccine was serologically distinct from cowpox,[5] and vaccinia was subsequently recognized as a separate viral species. Whole-genome sequencing has revealed that vaccinia is most closely related to horsepox, and the cowpox strains found in Great Britain are the least closely related to vaccinia.[6]
https://en.wikipedia.org/wiki/Vaccinia
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