ENL necroticans versus chicken pox versus small pox?

Leprosy Mailing List –  March 6^th, 2011

Ref:    ENL necroticans versus chicken pox versus small pox?

From: Fine PEM, London , UK

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Dear Salvatore,

Just to say  (I refer to Dr Salafia’s message dated 02/03/2011) that smallpox must be extremely extremely unlikely....

Aside from the question of the origin of the virus (variola virus is thought to exist now only in two BSL* category four facilities, one in Atlanta USA and one in Russia ), given that there has been no smallpox vaccination for 30 years it would spread rapidly in a human population.  There are, however, other orthopox viruses, such as cowpox... which do affect humans from time to time and are in general of low transmissibility from human to human.

Paul Fine

Paul EM Fine  VMD, PhD
Professor of Communicable Disease Epidemiology
London School of Hygiene and Tropical Medicine
Keppel Street
London WC1 7HT, UK

Tel:     (44)-[0]207-927-2219
Fax:    (44)-[0]207-636-8739

*

BSL stands for Biosafety level, or biosecurity level - on a scale from 1=low to 4=high.

There are strict rules and recommendations about cabinets and airflow and gloves and who is allowed into a lab and whether you need to change into a spacesuit etc. Smallpox virus is now held (must now be held only) under the highest possible security level.