Smallpox pathophysiology
|
Smallpox Microchapters |
|
Diagnosis |
|---|
|
Treatment |
|
Case Studies |
|
Smallpox pathophysiology On the Web |
|
American Roentgen Ray Society Images of Smallpox pathophysiology |
|
Risk calculators and risk factors for Smallpox pathophysiology |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
Overview
Transmission
Smallpox virus is transmitted by:[1]
- Physical contact
- Contact with infected body fluids
- Contact with infected objects
- Air through aerosolized particles
Genetics
Pathogenesis
The smallpox virus commonly enters the body through the upper respiratory tract, invading the oropharyngeal and respiratory mucosa.[2] Other possible ports of entry include: skin, conjunctivae as well as through the placenta.[3] Although the viral scabs may contain life viruses, they are commonly contained within thickened material, which limits transmissibility.
Once in the respiratory mucosa, the infection commonly progresses as:[4][3][5]
- Asymptomatic respiratory mucosa infection
- Viral replication within respiratory epithelium
- Transient primary asymptomatic viraemia
- Virus enters macrophages and spreads to lymph nodes and reticuloendothelial system, where it replicates during 4 - 14 days
- Exuberant secondary viraemia, leading to symptom onset
During secondary viraemia the virus infects mucous cells of the pharynx and mouth, and endothelium of the capillaries of the dermis, causing skin scabs. Other organs with high viral loads include:[5]
The immune system responds to the viremia with activation of lymphocytes T and B, with concomitant production of:[5]
- Neutralizing antibodies,during first week of disease
- Hemagglutination-inhibition antibodies, by the 16th day of infection
- Complement-fixation antibodies, by the 18th day of infection
Associated Conditions
Gross Pathology
Microscopic Pathology
References
- ↑ "Smallpox disease overview".
- ↑ Cecil, Russell (2012). Goldman's Cecil medicine. Philadelphia: Elsevier/Saunders. ISBN 1437716040.
- ↑ 3.0 3.1 "Smallpox and its Eradication" (PDF).
- ↑ Moore, Zack S; Seward, Jane F; Lane, J Michael (2006). "Smallpox". The Lancet. 367 (9508): 425–435. doi:10.1016/S0140-6736(06)68143-9. ISSN 0140-6736.
- ↑ 5.0 5.1 5.2 Breman, Joel G.; Henderson, D.A. (2002). "Diagnosis and Management of Smallpox". New England Journal of Medicine. 346 (17): 1300–1308. doi:10.1056/NEJMra020025. ISSN 0028-4793.