Evidence of Long-Distance Aerial Convection of Variola Virus and Implications for Disease Control.
Viruses
; 12(1)2019 12 27.
Article
en En
| MEDLINE
| ID: mdl-31892158
ABSTRACT
Two distinct phenomena of airborne transmission of variola virus (smallpox) were described in the pre-eradication era-direct respiratory transmission, and a unique phenomenon of transmission over greater distances, referred to as "aerial convection". We conducted an analysis of data obtained from a systematic review following the PRISMA criteria, on the long-distance transmission of smallpox. Of 8179 studies screened, 22 studies of 17 outbreaks were identified-12 had conclusive evidence of aerial convection and five had partially conclusive evidence. Aerial convection was first documented in 1881 in England, when smallpox incidence had waned substantially following mass vaccination, making unusual transmissions noticeable. National policy at the time stipulated spatial separation of smallpox hospitals from other buildings and communities. The evidence supports the transmission of smallpox through aerial convection at distances ranging from 0.5 to 1 mile, and one instance of 15 km related to bioweapons testing. Other explanations are also possible, such as missed chains of transmission, fomites or secondary aerosolization from contaminated material such as bedding. The window of observation of aerial convection was within the 100 years prior to eradication. Aerial convection appears unique to the variola virus and is not considered in current hospital infection control protocols. Understanding potential aerial convection of variola should be an important consideration in planning for smallpox treatment facilities and protecting potential contacts and surrounding communities.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Viruela
/
Convección
/
Microbiología del Aire
Tipo de estudio:
Guideline
/
Prognostic_studies
/
Systematic_reviews
Límite:
Humans
País/Región como asunto:
Europa
Idioma:
En
Revista:
Viruses
Año:
2019
Tipo del documento:
Article
País de afiliación:
Australia