Eastern equine encephalomyelitis in Panama: the epidemiology of the 1973 epizootic.
Abstract: In late June 1973, a small outbreak of equine encephalitis caused by eastern equine encephalomyelitis (EEE) virus occurred in the Republic of Panama. At least 100 horses were affected by the disease and 40 died. More than 1,700 human sera were obtained from areas of virus activity but no serological evidence for infection was found. Four isolates of EEE virus were recovered, one of which was from a small pool of Culex taeniopus mosquitoes. Serologic studies of infected horses and classification by the short incubation hemagglutination-inhibition tests revealed that these isolates were South American strains. Our evidence suggests that another agent virulent for horses was active during this outbreak.
Publication Date: 1980-01-01 PubMed ID: 7352621DOI: 10.4269/ajtmh.1980.29.133Google Scholar: Lookup
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- Journal Article
- Animal Health
- Diagnosis
- Disease control
- Disease Diagnosis
- Disease Etiology
- Disease Outbreaks
- Disease Surveillance
- Disease Treatment
- Encephalomyelitis
- Epidemiology
- Equine Diseases
- Equine Health
- Horses
- Infection
- Infectious Disease
- Mosquito-borne Diseases
- Pathogens
- Public Health
- Serological Surveys
- Veterinary Medicine
- Virus
Summary
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This research explores an outbreak of Eastern equine encephalomyelitis in Panama in 1973, specifically its impact on the horse population and the absence of any human infection evidence.
Introduction to the Outbreak
- In June 1973, Panama experienced an outbreak of Eastern equine encephalomyelitis (EEE), a viral disease that usually affects equines—such as horses, mules, and donkeys—but can also infect humans.
- Approximately 100 horses were infected during the outbreak, of which 40 died.
Serological Human Study
- In an effort to understand the extent of the disease, more than 1,700 human sera, or blood samples, were collected from areas impacted by the outbreak.
- However, no evidence of infection was found in these samples, suggesting that the virus had not crossed over from equines to humans during this particular outbreak.
Virus Isolation and Identification
- Scientists managed to recover four isolates, or samples, of the EEE virus during the investigation period.
- Interestingly, one of these samples was found in a small pool of Culex taeniopus mosquitoes. Culex taeniopus is a type of mosquito known to act as a vector, or carrier, for various viral diseases. This finding may suggest the route through which the horses got infected.
- The research team used serologic studies, which involve examination of the serums from infected horses, as well as classification via short incubation hemagglutination-inhibition tests, which are used to identify unknown viruses, to determine the specific strain of the EEE virus.
- Through these methods, they identified the isolates as the South American strain of the EEE virus.
Presence of Another Virulent Agent
- Despite the discovery of the EEE virus, the researchers’ evidence suggests that another disease-causing agent specifically virulent, or harmful, to horses was present during this outbreak.
- Although the paper doesn’t elaborate, this hypothesis hints at the possible co-occurrence of another yet unidentified health threat to the equine population at the same time as the EEE outbreak.
Cite This Article
APA
Dietz WH, Galindo P, Johnson KM.
(1980).
Eastern equine encephalomyelitis in Panama: the epidemiology of the 1973 epizootic.
Am J Trop Med Hyg, 29(1), 133-140.
https://doi.org/10.4269/ajtmh.1980.29.133 Publication
Researcher Affiliations
MeSH Terms
- Animals
- Antibodies, Viral / analysis
- Brain / microbiology
- Encephalitis Virus, Eastern Equine / isolation & purification
- Encephalomyelitis, Equine / epidemiology
- Encephalomyelitis, Equine / immunology
- Encephalomyelitis, Equine / veterinary
- Hemagglutination Inhibition Tests
- Horse Diseases / epidemiology
- Horses
- Humans
- Panama
Citations
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