African horse sickness: transmission and epidemiology.
Abstract: African horse sickness (AHS) virus causes a non-contagious, infectious, arthropod-borne disease of equines and occasionally of dogs. The virus is widely distributed across sub-Saharan African where it is transmitted between susceptible vertebrate hosts by the vectors. These are usually considered to be species of Culicoides biting midges but mosquitoes and/or ticks may also be involved to a greater or lesser extent. Periodically the virus makes excursions beyond its sub-Saharan enzootic zones but until recently does not appear to have been able to maintain itself outside these areas for more than 2-3 consecutive years at most. This is probably due to a number of factors including the apparent absence of a long term vertebrate reservoir, the prevalence and seasonal incidence of the vectors and the efficiency of control measures (vaccination and vector abatement). The recent AHS epizootics in Iberia and N Africa spanning as they do, 5 or more yr, seem to have established a new pattern in AHS virus persistence. This is probably linked to the continuous presence of adult C imicola in the area. Culicoides imicola is basically an Afro-Asiatic insect and prefers warm climates. Therefore its continuous adult presence in parts of Iberia and N Africa may be due to some recent moderations of the climate in these areas.
Publication Date: 1993-01-01 PubMed ID: 8102076
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- Journal Article
- Research Support
- Non-U.S. Gov't
- Review
- African Horse Sickness
- Animal Science
- Climate
- Culicoides
- Disease control
- Disease Management
- Disease Outbreaks
- Disease Prevalence
- Disease Transmission
- Epidemiology
- Equine Diseases
- Equine Health
- Horses
- Infectious Disease
- Mosquito-borne Diseases
- Public Health
- Tick-Borne Diseases
- Vector-borne disease
- Veterinary Medicine
- Virus
Summary
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The research article investigates the transmission and epidemiology of African horse sickness, a virus that affects horses and occasionally dogs, mostly in sub-Saharan Africa. It suggests that recent epidemics in Iberia and North Africa could indicate changes in the virus’s persistence due to climate changes that favor its mosquito and tick vectors.
Overview of African Horse Sickness
- African horse sickness (AHS) is a viral disease, primarily affecting horses but occasionally affecting dogs as well. It is arthropod-borne, meaning it is carried and spread by arthropods, small insects such as mosquitoes, ticks, and particularly species of Culicoides biting midges.
- The disease is non-contagious and is widely prevalent in the sub-Saharan Africa region.
- Despite its prevalence in the sub-Saharan region, the virus has not been able to maintain its persistence outside this area for periods longer than 2-3 consecutive years.
Virus Transmission and Control Measures
- Transmission of AHS occurs through vectors, mainly species of Culicoides biting midges. However, mosquitoes and ticks may also contribute to the spread of the disease.
- The inability of the virus to persist outside of its typical regions for more than a few consecutive years is possibly due to the absence of a long-term vertebrate reservoir, the prevalence and seasonal incidence of vectors, as well as efficacy of control measures such as vaccination and vector elimination.
Recent AHS Epidemics
- Recent epidemics of AHS in locations like Iberia and North Africa, lasting five or more years, have illustrated a possible change in the pattern of AHS virus’s persistence. This change could very well be related to the continuous presence of adult Culicoides imicola, which is an Afro-Asiatic insect.
Climate Change and AHS
- Culicoides imicola prefers warm climates, suggesting that climate modifications in areas like Iberia and North Africa may have contributed to these insects’ increased presence in these regions.
- The research implies that climate change may have a role in the persistence and spread of AHS virus outside its traditional geographical confines.
Cite This Article
APA
Mellor PS.
(1993).
African horse sickness: transmission and epidemiology.
Vet Res, 24(2), 199-212.
Publication
Researcher Affiliations
- Institute for Animal Health, Pirbright Laboratory, Woking, Surrey, UK.
MeSH Terms
- Africa, Northern / epidemiology
- African Horse Sickness / epidemiology
- African Horse Sickness / transmission
- African Horse Sickness Virus / physiology
- Animals
- Arachnid Vectors / microbiology
- Ceratopogonidae / microbiology
- Culicidae / microbiology
- Horses
- Insect Vectors / microbiology
- Portugal / epidemiology
- Spain / epidemiology
- Ticks / microbiology
References
This article includes 92 references
Citations
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