Reston virus
Encyclopedia
Introduction and Use of Term
Reston virus (abbreviated RESTV) was first described in 1990 as a new "strain" of Ebola virusEbola virus
Ebola virus causes severe disease in humans and in nonhuman primates in the form of viral hemorrhagic fever. EBOV is a Select Agent, World Health Organization Risk Group 4 Pathogen , National Institutes of Health/National Institute of Allergy and Infectious Diseases Category A Priority Pathogen,...
, a result of mutation from Ebola virus. It is the single member of the species
International Committee on Taxonomy of Viruses
The International Committee on Taxonomy of Viruses is a committee which authorizes and organizes the taxonomic classification of viruses. They have developed a universal taxonomic scheme for viruses and aim to describe all the viruses of living organisms. Members of the committee are considered to...
Reston ebolavirus, which is included into the genus
International Committee on Taxonomy of Viruses
The International Committee on Taxonomy of Viruses is a committee which authorizes and organizes the taxonomic classification of viruses. They have developed a universal taxonomic scheme for viruses and aim to describe all the viruses of living organisms. Members of the committee are considered to...
Ebolavirus
Ebolavirus
The genus Ebolavirus is a virological taxon included in the family Filoviridae, order Mononegavirales.This genus was introduced in 1998 as the "Ebola-like viruses". In 2002 the name was changed to Ebolavirus and in 2010 the genus was emended....
, family
International Committee on Taxonomy of Viruses
The International Committee on Taxonomy of Viruses is a committee which authorizes and organizes the taxonomic classification of viruses. They have developed a universal taxonomic scheme for viruses and aim to describe all the viruses of living organisms. Members of the committee are considered to...
Filoviridae
Filoviridae
The family Filoviridae is the taxonomic home of several related viruses that form filamentous virions. Two members of the family that are commonly known are Ebola virus and Marburg virus. Both viruses, and some of their lesser known relatives, cause severe disease in humans and nonhuman primates in...
, order
International Committee on Taxonomy of Viruses
The International Committee on Taxonomy of Viruses is a committee which authorizes and organizes the taxonomic classification of viruses. They have developed a universal taxonomic scheme for viruses and aim to describe all the viruses of living organisms. Members of the committee are considered to...
Mononegavirales
Mononegavirales
The order Mononegavirales is the taxonomic home of numerous related viruses. Members of the order that are commonly known are, for instance, Ebola virus, human respiratory syncytial virus, measles virus, mumps virus, Nipah virus, and rabies virus. All of these viruses cause significant disease in...
. The name Reston virus is derived from Reston
Reston, Virginia
Reston is a census-designated place in Fairfax County, Virginia, United States, within the Washington, D.C. metropolitan area. The population was 58,404, at the 2010 Census and 56,407 at the 2000 census...
(the town of Virginia
Virginia
The Commonwealth of Virginia , is a U.S. state on the Atlantic Coast of the Southern United States. Virginia is nicknamed the "Old Dominion" and sometimes the "Mother of Presidents" after the eight U.S. presidents born there...
, USA, in which Reston virus was first discovered) and the taxonomic
Taxonomy
Taxonomy is the science of identifying and naming species, and arranging them into a classification. The field of taxonomy, sometimes referred to as "biological taxonomy", revolves around the description and use of taxonomic units, known as taxa...
suffix
Suffix
In linguistics, a suffix is an affix which is placed after the stem of a word. Common examples are case endings, which indicate the grammatical case of nouns or adjectives, and verb endings, which form the conjugation of verbs...
virus. Reston virus is pronounced ‘rɛstən vɑɪrəs (IPA) or res-tuhn vahy-ruhs in English phonetic notation. According to the rules for taxon naming established by the International Committee on Taxonomy of Viruses
International Committee on Taxonomy of Viruses
The International Committee on Taxonomy of Viruses is a committee which authorizes and organizes the taxonomic classification of viruses. They have developed a universal taxonomic scheme for viruses and aim to describe all the viruses of living organisms. Members of the committee are considered to...
(ICTV), the name Reston virus is always to be capitalized
Capitalization
Capitalization is writing a word with its first letter as a majuscule and the remaining letters in minuscules . This of course only applies to those writing systems which have a case distinction...
, but is never italicized
Italic type
In typography, italic type is a cursive typeface based on a stylized form of calligraphic handwriting. Owing to the influence from calligraphy, such typefaces often slant slightly to the right. Different glyph shapes from roman type are also usually used—another influence from calligraphy...
, and may be abbreviated
Abbreviation
An abbreviation is a shortened form of a word or phrase. Usually, but not always, it consists of a letter or group of letters taken from the word or phrase...
(with RESTV being the official abbreviation).
Previous designations
Reston virus was first introduced as a new "strain" of Ebola virus in 1990. In 2000, it received the designation Reston Ebola virus and in 2002 the name was changed to Reston ebolavirus. Previous abbreviations for the virus were EBOV-R (for Ebola virus Reston) and most recently REBOV (for Reston Ebola virus or Reston ebolavirus). The virus received its final designation in 2010, when it was renamed Reston virus (RESTV).Virus Inclusion Criteria
A virus of the species Reston ebolavirus is a Reston virus (RESTV) if it has the properties of Reston ebolaviruses and if its genomeGenome
In modern molecular biology and genetics, the genome is the entirety of an organism's hereditary information. It is encoded either in DNA or, for many types of virus, in RNA. The genome includes both the genes and the non-coding sequences of the DNA/RNA....
diverges from that of the prototype Reston virus, Reston virus variant Pennsylvania (RESTV/Pen), by ≤10% at the nucleotide
Nucleotide
Nucleotides are molecules that, when joined together, make up the structural units of RNA and DNA. In addition, nucleotides participate in cellular signaling , and are incorporated into important cofactors of enzymatic reactions...
level.
History and Current Knowledge
RESTV was discovered in crab-eating macaquesCrab-eating Macaque
The Crab-eating macaque is a cercopithecine primate native to Southeast Asia. It is also called the "long-tailed macaque", and is referred to as the "cynomolgus monkey" in laboratories.-Etymology:...
from Hazleton Laboratories
Covance
Covance, Inc. , formerly Corning Incorporated, with headquarters in Princeton, New Jersey, USA, is a contract research organization , providing drug development and animal testing services...
(now Covance) in 1989. This attracted significant media attention due to the proximity of Reston to the Washington, DC metro area, and the lethality of a closely related virus, Ebola virus
Ebola virus
Ebola virus causes severe disease in humans and in nonhuman primates in the form of viral hemorrhagic fever. EBOV is a Select Agent, World Health Organization Risk Group 4 Pathogen , National Institutes of Health/National Institute of Allergy and Infectious Diseases Category A Priority Pathogen,...
(EBOV). Despite its status as a level-4 organism, Reston virus is non-pathogen
Pathogen
A pathogen gignomai "I give birth to") or infectious agent — colloquially, a germ — is a microbe or microorganism such as a virus, bacterium, prion, or fungus that causes disease in its animal or plant host...
ic to humans however hazardous to monkeys; the perception of its lethality was confounded due to the monkey's coinfection
Coinfection
In parasitology, coinfection is the term used to describe the simultaneous infection of a host by multiple pathogen species. In virology, coinfection can also refer to the simultaneous infection of a single cell by two or more virus particles...
with Simian hemorrhagic fever virus
Simian hemorrhagic fever virus
Simian hemorrhagic fever virus or simian haemorrhagic fever virus or SHFV is a highly pathogenic virus in monkeys. It is a positive-stranded RNA virus classified in the family Arteriviridae.- Hosts :...
(SHFV).
Discovery
While investigating on an outbreak of Simian hemorrhagic feverSimian hemorrhagic fever virus
Simian hemorrhagic fever virus or simian haemorrhagic fever virus or SHFV is a highly pathogenic virus in monkeys. It is a positive-stranded RNA virus classified in the family Arteriviridae.- Hosts :...
(SHFV) in November of 1989, an electron microscopist
Electron microscope
An electron microscope is a type of microscope that uses a beam of electrons to illuminate the specimen and produce a magnified image. Electron microscopes have a greater resolving power than a light-powered optical microscope, because electrons have wavelengths about 100,000 times shorter than...
from USAMRIID
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...
discovered filoviruses similar in appearance to Ebola virus
Ebola virus
Ebola virus causes severe disease in humans and in nonhuman primates in the form of viral hemorrhagic fever. EBOV is a Select Agent, World Health Organization Risk Group 4 Pathogen , National Institutes of Health/National Institute of Allergy and Infectious Diseases Category A Priority Pathogen,...
in tissue samples taken from Crab-eating Macaque
Crab-eating Macaque
The Crab-eating macaque is a cercopithecine primate native to Southeast Asia. It is also called the "long-tailed macaque", and is referred to as the "cynomolgus monkey" in laboratories.-Etymology:...
imported from the Philippines
Philippines
The Philippines , officially known as the Republic of the Philippines , is a country in Southeast Asia in the western Pacific Ocean. To its north across the Luzon Strait lies Taiwan. West across the South China Sea sits Vietnam...
to Hazleton Laboratories
Covance
Covance, Inc. , formerly Corning Incorporated, with headquarters in Princeton, New Jersey, USA, is a contract research organization , providing drug development and animal testing services...
in Reston, Virginia
Reston, Virginia
Reston is a census-designated place in Fairfax County, Virginia, United States, within the Washington, D.C. metropolitan area. The population was 58,404, at the 2010 Census and 56,407 at the 2000 census...
. The filovirus was further isolated by Dr. Peter B. Jahrling, and over the period of three months over a third of the monkeys died—at a rate of two or three a day.
Blood samples were taken from 178 animal handlers during the incident. Of them, six eventually seroconverted, testing positive using ELISA
ELISA
Enzyme-linked immunosorbent assay , is a popular format of a "wet-lab" type analytic biochemistry assay that uses one sub-type of heterogeneous, solid-phase enzyme immunoassay to detect the presence of a substance in a liquid sample."Wet lab" analytic biochemistry assays involves detection of an...
. They remained, however, asymptomatic. In January 1990, an animal handler at Hazelton cut himself while performing a necropsy on the liver of an infected Cynomolgus. Under the direction of the Center for Disease Control and Prevention (CDC) the animal handler was placed under surveillance for the duration of the incubation period
Incubation period
Incubation period is the time elapsed between exposure to a pathogenic organism, a chemical or radiation, and when symptoms and signs are first apparent...
. When the animal handler failed to become ill, it was concluded that the virus had a low pathogen
Pathogen
A pathogen gignomai "I give birth to") or infectious agent — colloquially, a germ — is a microbe or microorganism such as a virus, bacterium, prion, or fungus that causes disease in its animal or plant host...
icity in humans.
Investigation
Centers for Disease Control and Prevention
The Centers for Disease Control and Prevention are a United States federal agency under the Department of Health and Human Services headquartered in Druid Hills, unincorporated DeKalb County, Georgia, in Greater Atlanta...
. The monkeys were imported from the Philippines, which had no previous record of SHFV or ebolavirus infections. It was suspected that the monkeys contracted both diseases while in transit aboard KLM airlines before reaching Reston. Shipments were tracked to New York City
New York City
New York is the most populous city in the United States and the center of the New York Metropolitan Area, one of the most populous metropolitan areas in the world. New York exerts a significant impact upon global commerce, finance, media, art, fashion, research, technology, education, and...
, Texas
Texas
Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...
, and Mexico City
Mexico City
Mexico City is the Federal District , capital of Mexico and seat of the federal powers of the Mexican Union. It is a federal entity within Mexico which is not part of any one of the 31 Mexican states but belongs to the federation as a whole...
, none of which produced cases of infection.
By January 1990, Hazelton Laboratories recovered from its previous losses and began importing monkeys again from the same establishment in Manila
Manila
Manila is the capital of the Philippines. It is one of the sixteen cities forming Metro Manila.Manila is located on the eastern shores of Manila Bay and is bordered by Navotas and Caloocan to the north, Quezon City to the northeast, San Juan and Mandaluyong to the east, Makati on the southeast,...
that had provided the original animals. The imported monkeys became infected and were euthanized. In early February the CDC received reports of the disease in Alice, Texas. In March the Division of Quarantine at the CDC secured a temporary ban on the import
Import
The term import is derived from the conceptual meaning as to bring in the goods and services into the port of a country. The buyer of such goods and services is referred to an "importer" who is based in the country of import whereas the overseas based seller is referred to as an "exporter". Thus...
ation of monkeys into the United States from anywhere in the world.
Following the announcement of the filovirus disease outbreak in Reston, Virginia, a serosurvey was conducted to assess the prevalence of the infection. Of the several hundred serums received by the CDC, approximately ten percent showed some reaction to ebolavirus antigen—though usually at low levels. Counterintuitively, the majority of the monkeys found positive were from Indonesia
Indonesia
Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...
.
In May 1990 an investigation led by Susan Fisher-Hoch, Steve Ostroff, and Jerry Jennings was sent to Indonesia. During the investigation, it was hypothesized
Hypothesis
A hypothesis is a proposed explanation for a phenomenon. The term derives from the Greek, ὑποτιθέναι – hypotithenai meaning "to put under" or "to suppose". For a hypothesis to be put forward as a scientific hypothesis, the scientific method requires that one can test it...
that there could be a cross infection
Coinfection
In parasitology, coinfection is the term used to describe the simultaneous infection of a host by multiple pathogen species. In virology, coinfection can also refer to the simultaneous infection of a single cell by two or more virus particles...
since monkeys suspected of illness were typically placed in gang cages containing up to twenty to thirty other monkeys suspected of illness. Upon arrival they were told that most of the monkeys were imported from the island of Sumatra
Sumatra
Sumatra is an island in western Indonesia, westernmost of the Sunda Islands. It is the largest island entirely in Indonesia , and the sixth largest island in the world at 473,481 km2 with a population of 50,365,538...
. The investigation team found no trace of the virus in either case.
Following the investigation in Indonesia, an experiment was conducted in the level-4 lab at the CDC campus in DeKalb County, Georgia
DeKalb County, Georgia
DeKalb County is a county located in the U.S. state of Georgia. The population of the county was 691,893 at the 2010 census. Its county seat is the city of Decatur. It is bordered to the west by Fulton County and contains roughly 10% of the city of Atlanta...
with thirty-two monkeys: sixteen Green monkey
Green Monkey
The green monkey , also known as the Callithrix monkey, is an Old World monkey with golden-green fur and pale hands and feet. The tip of the tail is golden yellow as are the backs of the thighs and cheek whiskers. It does not have a distinguishing band of fur on the brow, like other Chlorocebus...
s (Cercopithecus aethiops) and sixteen Crab-eating Macaques. Half of the sixteen Green monkeys and Crab-eating Macaques were infected with Reston virus and the other half with Ebola virus. Ebola virus infection was lethal to nearly all monkeys. However, most of the monkeys infected with Reston virus recovered in a month. The surviving monkeys were kept for two years to detect any trace of the virus - none was found. However, the monkeys continued to possess a high level of antigen
Antigen
An antigen is a foreign molecule that, when introduced into the body, triggers the production of an antibody by the immune system. The immune system will then kill or neutralize the antigen that is recognized as a foreign and potentially harmful invader. These invaders can be molecules such as...
.
Post-Reston
Following the test at the CDC campus in DeKalb County, GeorgiaDeKalb County, Georgia
DeKalb County is a county located in the U.S. state of Georgia. The population of the county was 691,893 at the 2010 census. Its county seat is the city of Decatur. It is bordered to the west by Fulton County and contains roughly 10% of the city of Atlanta...
, two of the monkeys who had survived Reston virus infection were infected with a very large dose of the Ebola virus in an effort to produce an Ebola vaccine. One of the two monkeys remained resistant; the second died.
The physical building in which the outbreak occurred was demolished on 30 May 1995 and a new building constructed in its place. This facility, which is part of the Isaac Newton Square office park, located at 1946 Isaac Newton Sq W, Reston, Virginia
Reston, Virginia
Reston is a census-designated place in Fairfax County, Virginia, United States, within the Washington, D.C. metropolitan area. The population was 58,404, at the 2010 Census and 56,407 at the 2000 census...
, became a KinderCare, then became a Mulberry Child Care and preschool center as of 2007, and as of 2009 is once again a KinderCare.
Reston virus reemerged in Italy in 1992, and again in a monkey export facility in the Philippines in 1996.
On 11 December 2008, pigs from farms slightly north of Manila
Manila
Manila is the capital of the Philippines. It is one of the sixteen cities forming Metro Manila.Manila is located on the eastern shores of Manila Bay and is bordered by Navotas and Caloocan to the north, Quezon City to the northeast, San Juan and Mandaluyong to the east, Makati on the southeast,...
, Philippines
Philippines
The Philippines , officially known as the Republic of the Philippines , is a country in Southeast Asia in the western Pacific Ocean. To its north across the Luzon Strait lies Taiwan. West across the South China Sea sits Vietnam...
tested positive for the virus. The CDC
Centers for Disease Control and Prevention
The Centers for Disease Control and Prevention are a United States federal agency under the Department of Health and Human Services headquartered in Druid Hills, unincorporated DeKalb County, Georgia, in Greater Atlanta...
and the World Health Organization
World Health Organization
The World Health Organization is a specialized agency of the United Nations that acts as a coordinating authority on international public health. Established on 7 April 1948, with headquarters in Geneva, Switzerland, the agency inherited the mandate and resources of its predecessor, the Health...
are investigating. On 23 January 2009, Philippine health officials announced that a hog farm worker had been infected with the virus. Although the man was asymptomatic and the source of the infection is uncertain, this could represent the first case of pig-to-human transmission of Reston virus - a fact that could cause concern, as pigs may be able to transmit more deadly diseases to humans. The situation is undergoing further investigation.