Ames strain
Encyclopedia
The Ames strain is one of 89 known strains
of the anthrax
bacterium (Bacillus anthracis
). It was isolated from a diseased 14-month old Beefmaster
heifer that died in Sarita, Texas
in 1981. The strain was isolated at the Texas Veterinary Medical Diagnostic Laboratory
and a sample was sent to the United States Army Medical Research Institute of Infectious Diseases
(USAMRIID). Researchers at USAMRIID mistakenly believed the strain came from Ames, Iowa
because the return address on the package was the USDA's National Veterinary Services Laboratories in Ames and mislabeled the specimen.
The Ames strain came to wide public attention in association with the 2001 anthrax attacks
. Seven letters mailed to media outlets and US Senators on September 18, 2001 and October 9, 2001 contained anthrax bacteria of this particular strain. This strain is a monomorphic disease, mutating slowly if at all.
Because of its virulence
, the Ames strain is used by the United States as a "gold standard" for development of vaccine
s and testing their effectiveness, starting in the 1980s, after work on weaponizing the Vollum 1B strain ended and all weaponized stocks were destroyed after the end of the U.S. biological warfare
program in 1969.
Strain (biology)
In biology, a strain is a low-level taxonomic rank used in three related ways.-Microbiology and virology:A strain is a genetic variant or subtype of a micro-organism . For example, a "flu strain" is a certain biological form of the influenza or "flu" virus...
of the anthrax
Anthrax
Anthrax is an acute disease caused by the bacterium Bacillus anthracis. Most forms of the disease are lethal, and it affects both humans and other animals...
bacterium (Bacillus anthracis
Bacillus anthracis
Bacillus anthracis is the pathogen of the Anthrax acute disease. It is a Gram-positive, spore-forming, rod-shaped bacterium, with a width of 1-1.2µm and a length of 3-5µm. It can be grown in an ordinary nutrient medium under aerobic or anaerobic conditions.It is one of few bacteria known to...
). It was isolated from a diseased 14-month old Beefmaster
Beefmaster
Beefmaster is a breed of beef cattle that was developed in the early 1930s by Tom Lasater from a crossing of Hereford and Shorthorn cattle with Brahman stock. The exact mixture of the foundation cattle is unknown, but is thought to be about 25% Hereford, 25% Shorthorn and 50% Brahman. It was the...
heifer that died in Sarita, Texas
Sarita, Texas
Sarita is an census designated place in, and the county seat of Kenedy County, Texas, United States,. It is the only settlement of note in the county, and as of the 2010 US Census had a population of 238.-History:...
in 1981. The strain was isolated at the Texas Veterinary Medical Diagnostic Laboratory
Texas Veterinary Medical Diagnostic Laboratory
Texas Veterinary Medical Diagnostic Laboratory is an integral part of the Texas A&M University System.Texas Veterinary Medical Diagnostic Laboratory contains some of the busiest full-service veterinary diagnostic laboratories in the world...
and a sample was sent to the United States Army Medical Research Institute of Infectious Diseases
United States Army Medical Research Institute of Infectious Diseases
The U.S. Army Medical Research Institute of Infectious Diseases is the U.S Army’s main institution and facility for defensive research into countermeasures against biological warfare. It is located on Fort Detrick, Maryland and is a subordinate lab of the U. S...
(USAMRIID). Researchers at USAMRIID mistakenly believed the strain came from Ames, Iowa
Ames, Iowa
Ames is a city located in the central part of the U.S. state of Iowa in Story County, and approximately north of Des Moines. The U.S. Census Bureau designates that Ames, Iowa metropolitan statistical area as encompassing all of Story County, and which, when combined with the Boone, Iowa...
because the return address on the package was the USDA's National Veterinary Services Laboratories in Ames and mislabeled the specimen.
The Ames strain came to wide public attention in association with the 2001 anthrax attacks
2001 anthrax attacks
The 2001 anthrax attacks in the United States, also known as Amerithrax from its Federal Bureau of Investigation case name, occurred over the course of several weeks beginning on Tuesday, September 18, 2001, one week after the September 11 attacks. Letters containing anthrax spores were mailed to...
. Seven letters mailed to media outlets and US Senators on September 18, 2001 and October 9, 2001 contained anthrax bacteria of this particular strain. This strain is a monomorphic disease, mutating slowly if at all.
Because of its virulence
Virulence
Virulence is by MeSH definition the degree of pathogenicity within a group or species of parasites as indicated by case fatality rates and/or the ability of the organism to invade the tissues of the host. The pathogenicity of an organism - its ability to cause disease - is determined by its...
, the Ames strain is used by the United States as a "gold standard" for development of vaccine
Vaccine
A vaccine is a biological preparation that improves immunity to a particular disease. A vaccine typically contains an agent that resembles a disease-causing microorganism, and is often made from weakened or killed forms of the microbe or its toxins...
s and testing their effectiveness, starting in the 1980s, after work on weaponizing the Vollum 1B strain ended and all weaponized stocks were destroyed after the end of the U.S. biological warfare
Biological warfare
Biological warfare is the use of biological toxins or infectious agents such as bacteria, viruses, and fungi with intent to kill or incapacitate humans, animals or plants as an act of war...
program in 1969.