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Hantavirus and arenavirus antibodies in persons with occupational rodent exposure, North America.



Rodents are the principal hosts of Sin Nombre virus The Sin Nombre virus (literally "unnamed virus" in Spanish) (SNV) is the prototypical etiologic agent of hantavirus cardiopulmonary syndrome (HCPS). It was first isolated from rodents collected near the home of one of the initial patients with hantavirus pulmonary syndrome , 4 other hantaviruses known to cause hantavirus pulmonary syndrome hantavirus pulmonary syndrome An often fatal RTI caused by a hantavirus; the first cluster occurred in the Four Corners region of Southwestern US Epidemiology Mean age 32, 61% ♀, 72% Native American Case definition Unexplained bilateral interstitial  in North America North America, third largest continent (1990 est. pop. 365,000,000), c.9,400,000 sq mi (24,346,000 sq km), the northern of the two continents of the Western Hemisphere. , and the 3 North American North American

named after North America.


North American blastomycosis
see North American blastomycosis.

North American cattle tick
see boophilusannulatus.
 arenaviruses. Serum samples from 757 persons who had worked with rodents in North America and handled neotomine or sigmodontine rodents were tested for antibodies against Sin Nombre virus, Whitewater Arroyo virus, Guanarito virus Guanarito virus Virology An emerging viral pathogen of the Lassa and Arenavirus family. See Emerging pathogen. , and lymphocytic choriomeningitis virus lymphocytic choriomeningitis virus
n.
A virus of the genus Arenavirus that is the causative agent of lymphocytic choriomeningitis.
. Antibodies against Sin Nombre virus were found in 4 persons, against Whitewater Arroyo virus or Guanarito virus in 2 persons, and against lymphocytic choriomeningitis virus in none. These results suggest that risk for infection with hantaviruses or arenaviruses usually is low in persons whose occupations entail close physical contact with neotomine or sigmodontine rodents in North America.

**********

Hantavirus pulmonary syndrome (HPS See Seer*HPS. ) is a frequently fatal rodentbome viral zoonosis Zoonosis Definition

Zoonosis, also called zoonotic disease refers to diseases that can be passed from animals, whether wild or domesticated, to humans.
. Seven species in the virus family Bunyaviridae, genus Hantavirus hantavirus, any of a genus (Hantavirus) of single-stranded RNA viruses that are carried by rodents and transmitted to humans when they inhale vapors from contaminated rodent urine, saliva, or feces. There are many strains of hantavirus.  (1), have been causally associated with HPS: Sin Nombre virus (SNV SNV Synovus Financial Corp. (stock symbol)
SNV Schweizerische Normenvereinigung (Swiss standards body)
SNV Stichting Nederlandse Vrijwilligers (Netherlands Development Organization) 
), New York New York, state, United States
New York, Middle Atlantic state of the United States. It is bordered by Vermont, Massachusetts, Connecticut, and the Atlantic Ocean (E), New Jersey and Pennsylvania (S), Lakes Erie and Ontario and the Canadian province of
 virus (NYV NYV New York Voices (musical group) ), Black Creek Black Creek may refer to:

In the United States:
  • Georgia:
  • Black Creek (Georgia), a tributary of the Savannah River
  • Mississippi:
 Canal virus (BCCV BCCV Border Collie Club of Victoria (Australia) ), Bayou virus (BAYV), and Choclo virus (CHOV) in North America (2-6), and Andes virus (ANDV) and Laguna Negra virus (LANV) in South America (7,8).

The virus family Arenaviridae, genus Arenavirus arenavirus /are·na·vi·rus/ (ah-re´nah-vi?rus) any virus of the family Arenaviridae.
Arenavirus /Are·na·vi·rus/ (ah-re´nah-vi?rus 
, includes 3 North American species and 14 South American species (9). The North American species are Bear Canyon virus (BCNV), Tamiami virus (TAMV), and Whitewater Arroyo virus (WWAV). The South American species include Guanarito virus (GTOV), Junin virus (JUNV), Machupo virus (MACV MACV Military Assistance Command Vietnam
MACV Mine Area Clearance Vehicle
), and Sabia virus Sa·bi·a virus
n.
An arbovirus having an incubation period of about 12 days and causing fever, rashes, and other infectionlike symptoms as well as hemorrhagic bleeding from internal organs, mouth, nose, and other mucous membranes.
 (SABV SABV Sabia Virus
SABV Saboya Virus
SABV South Australian Business Vision (Australia)
SABV Secondary Air Bypass Valve
SABV Super Appending Batch Virus (computer virus) 
). These 4 South American species have been causally associated with severe human disease in Venezuela, Argentina, Bolivia, and Brazil, respectively (10). The human health importance of the North American arenavirus species has not been rigorously investigated.

Specific members of the subfamilies Neotominae and Sigmodontinae in the rodent family Cricetidae (11) are the principal hosts (reservoirs) of the hantaviruses known to cause HPS in North America and the 3 North American arenaviruses. For example, principal hosts and their respective viruses include: the deer mouse (Peromyscus maniculatus) in Canada and the western United States Noun 1. western United States - the region of the United States lying to the west of the Mississippi River
West

Santa Fe Trail - a trail that extends from Missouri to New Mexico; an important route for settlers moving west in the 19th century
, SNV (12,13); the white-footed mouse (Peromyscus leucopus Peromyscus leucopus

deermouse; called also white-footed mouse.
) in the northeastern United States, NYV (3); the hispid cotton rat The Hispid Cotton Rat, Sigmodon hispidus, is a rodent species long thought to occur in parts of South America, Central America, and southern North America. However, recent taxonomic revisions, based on mitochondrial DNA sequence data, have split this widely distributed  (Sigmodon hispidus) in Florida, BCCV and TAMV (4,14); the marsh rice rat The Marsh Rice Rat (Oryzomys palustris) is a species of rodent in the Cricetidae family. It is found only in the United States. Its natural habitats are subtropical or tropical swamps, subtropical or tropical seasonally wet or flooded lowland grassland, swamps, and  (Oryzomys palustris) in the southeastern United States, BAYV (15-17); the fulvous Ful´vous

a. 1. Tawny; dull yellow, with a mixture of gray and brown.
 colilargo (Oligoryzomys fidvescens) in Panama, CHOV (6); the California mouse (Peromyscus californicus) in California, BCNV (18); and the white-throated woodrat (Neotoma albigula) in New Mexico, WWAV (19). P. maniculatus, P. leucopus, P. californicus, and N. albigula are members of the Neotominae and S. hispidus, O. palustris, and O. fulvescens are members of the Sigmodontinae (11).

It is assumed that humans usually become infected with hantaviruses and arenaviruses by inhalation of aerosolized Adj. 1. aerosolized - in the form of ultramicroscopic solid or liquid particles dispersed or suspended in air or gas
aerosolised

gaseous - existing as or having characteristics of a gas; "steam is water is the gaseous state"
 droplets of urine, saliva, or respiratory secretions from infected rodents. Other means of infection include, but are not limited to, inhalation of dust or other organic matter contaminated contaminated,
v 1. made radioactive by the addition of small quantities of radioactive material.
2. made contaminated by adding infective or radiographic materials.
3. an infective surface or object.
 with infectious virus and contact of infectious materials with mucous membranes Mucous membranes
The inner tissue that covers or lines body cavities or canals open to the outside, such as nose and mouth. These membranes secrete mucus and absorb water and salts.

Mentioned in: Leprosy, Pulmonary Fibrosis, Topical Anesthesia
.

The purpose of this study was to assess the risk for hantavirus and arenavirus infections among persons who work in North America and have close physical contact with neotomine rodents or sigmodontine rodents through their occupations. These persons include mammalogists This is a list of notable mammalogists, in alphabetical order by surname. A-D
  • Joanna Cobb (USA)
  • James Dines
  • Rachel Bennett
E-H
  • Dian Fossey (USA)
  • Jane Goodall (UK)
  • Ines Horovitz (USA)
  • Shekinah Argudo (USA)
I-L
, wildlife biologists, scientists whose research concerns the ecology of rodentborne zoonoses Zoonoses

Infections of humans caused by the transmission of disease agents that naturally live in animals. People become infected when they unwittingly intrude into the life cycle of the disease agent and become unnatural hosts.
, and pest control operators.

Materials and Methods

Study Population

The persons in this study were participants in a survey conducted in 1994 by the Centers for Disease Control and Prevention Centers for Disease Control and Prevention (CDC), agency of the U.S. Public Health Service since 1973, with headquarters in Atlanta; it was established in 1946 as the Communicable Disease Center.  (CDC See Control Data, century date change and Back Orifice.

CDC - Control Data Corporation
). The primary objective of the survey was to assess the risk for hantavirus infections Hantavirus Infections Definition

Hantavirus infection is caused by a group of viruses that can infect humans with two serious illnesses: hemorrhagic fever with renal syndrome (HFRS), and Hantavirus pulmonary syndrome (HPS).
 in persons whose occupations expose them to rodents. Participation in the survey was voluntary and entailed completion of a self-administered questionnaire and donation of a small volume of venous blood venous blood
n. Abbr. v
Blood that has passed through the capillaries of various tissues other than the lungs, is found in the veins, in the right chambers of the heart, and in pulmonary arteries, and is usually dark red as a result of a
. Most of the 995 participants were enrolled at 1 of the following: American Society of Mammalogists The American Society of Mammalogists (ASM) was founded in 1919. Its primary purpose is to encourage the study of mammals and professions studying mammals. There are over 4,500 members of this society, and they are primarily professional scientists who emphasize the importance of  meeting (Washington, DC, 1994), Wildlife Disease Association meeting (Pacific Grove, California Pacific Grove is a coastal town in Monterey County, California, USA, with a total population of 15,522 as of the 2000 census.

Pacific Grove is known for its Victorian homes, Asilomar State Beach, its artistic legacy and the annual migration of the Monarch butterflies.
, 1994), Southwestern Association of Naturalists meeting (Emporia, Kansas, 1994), Wildlife Society meeting (Wenatchee, Washington, 1994), 16th Vertebrate Pest Conference (Santa Clara, California Santa Clara, California (IPA: /ˌsæntəˈklærə/) , founded in 1777 and incorporated in 1852, is a city in Santa Clara County, in the U.S. state of California. , 1994), and Colorado Pest Control Meeting (Denver, Colorado, 1994). The other participants mailed their completed questionnaires and serum samples directly to CDC.

The questionnaire included detailed questions about previous exposure to rodents, use of personal protective equipment to minimize exposure to rodent excretions and secretions, and any previous occurrence of a severe febrile febrile /feb·rile/ (feb´ril) pertaining to or characterized by fever.

feb·rile
adj.
Of, relating to, or characterized by fever; feverish.
 illness that included shortness of breath Shortness of Breath Definition

Shortness of breath, or dyspnea, is a feeling of difficult or labored breathing that is out of proportion to the patient's level of physical activity.
. The lifetime number of rodents handled by a person was measured categorically: I (1-99), II (100-499), III (500-999), IV (1,000-9,999), V (10,000-49,999), and VI ([greater than or equal to] 50,000). Use of gloves, protective masks equipped with high efficiency particulate air (HEPA HEPA  
abbr.
1. high-efficiency particulate air

2. high-efficiency particulate arresting
) filters, and protective eyewear protective eyewear,
n See eyewear, protective.
 also was measured categorically: always (>90% of the time), usually (50%-90% of the time), sometimes (10%-49% of the time), seldom (<10% of the time), or never.

This study was restricted to the 757 participants in the CDC survey who had a history of exposure to rodents in North America and a history of occupational exposure to deer mice deer mice Peromyscus maniculatus Public health The murine vector for Hantavirus. See Hantavirus. , white-footed mice, California mice, woodrats (Neotoma spp.), other neotomine rodents, cotton rats (Sigmodon spp.), oryzomyine rodents (Oryzomys spp. or Oligoryzomys spp.), or other sigmodontine rodents. Of the persons included in the study, 699 had worked with rodents only in North America. The 58 others had worked with rodents in North America and in South America. The geographic distribution of exposure to rodents in North America was Canada (n = 36), Alaska (n = 8), the contiguous United States or District of Columbia District of Columbia, federal district (2000 pop. 572,059, a 5.7% decrease in population since the 1990 census), 69 sq mi (179 sq km), on the east bank of the Potomac River, coextensive with the city of Washington, D.C. (the capital of the United States).  (n = 726, Table 1), Mexico (n = 91), Guatemala (n = 8), Belize (n = 3), Honduras (n = 3), Costa Rica (n = 21), Nicaragua (n = 4), and Panama (n = 8). Of the persons included in the study, 468 (61.8%) had worked with rodents in >1 state within the contiguous United States.

Persons included in the study had worked with rodents from 1 month to 65 years (mean 12.5 years). The total number of rodents handled by any 1 person ranged from category I (1-99) to category VI ([greater than or equal to] 50,000); the median was IV (1,000-9,999). Of the 757 persons in the study, 751 (99.2%) had handled deer mice, white-footed mice, cotton rats, oryzomyine rodents, California mice, or woodrats (Table 2).

HPS was first recognized as a clinical entity in 1993 in the southwestern United States (20). From March 1, 1993, through September 19, 2006, a total of 453 laboratory-confirmed HPS cases were reported to CDC from the contiguous United States (www.cdc.gov/ncidod/diseases/ hanta/hps/noframes/epislides/episl7.htm). Of these, 259 (57.2%) were reported from 6 states in the southwestern United States: Colorado (n = 51), New Mexico (n = 71), Utah (n = 25), Arizona (n = 49), Nevada (n = 18), and California (n = 45). SNV is the only virus known to cause HPS in these 6 states. In this study, 387 (51.1%) persons had worked with rodents in Colorado (n = 124), New Mexico (n = 111), Utah (n = 65), Arizona (n = 90), Nevada (n = 33), or California (n = 169) and had handled deer mice. The total number of deer mice handled by persons in this group ranged from I (1-99) to VI (>50,000); the median was II (100-499).

The geographic range of BAYV includes Georgia, Louisiana, and Texas (5,15-17), BCCV has been found only in Florida (4), and the geographic range of NYV includes New York, Pennsylvania, and Rhode Island Rhode Island, island, United States
Rhode Island, island, 15 mi (24 km) long and 5 mi (8 km) wide, S R.I., at the entrance to Narragansett Bay. It is the largest island in the state, with steep cliffs and excellent beaches.
 (3,21,22). In this study, 22 persons had worked with rodents in Georgia (n = 1), Louisiana (n = 2), or Texas (n = 20) and handled oryzomyine rodents. The total number of oryzomyine rodents handled by persons in this group ranged from I (1-99) to IV (1,000-9,999); the median was I (1-99). Fourteen persons had worked with rodents in Florida and handled cotton rats. The total number of cotton rats handled by persons in this group ranged from I (1-99) to IV (1,000-9,999); the median was II (100-499). Eighty-one persons had worked with rodents in New York (n = 45), Pennsylvania (n = 42), or Rhode Island (n = 5) and handled white-footed mice. The total number of white-footed mice handled by persons in this group ranged from I (1-99) to V (10,000-49,999); the median was II (100-499).

BCNV virus has been found only in California (18) and TAMV only in Florida (14); the geographic range of WWAV and other arenaviruses naturally associated with woodrats (Neotoma spp.) includes Arizona, California, Colorado, New Mexico, Oklahoma, Utah, and Texas (19,23-27). In this study, 31 persons had worked with rodents in California and handled California mice (P. californicus). The total number of California mice handled by persons in this group ranged from I (1-99) to III (500-999); the median was I (1-99). As indicated previously, 14 persons had worked with rodents in Florida and handled cotton rats. Three hundred and thirty-three persons had worked with rodents in Arizona (n = 87), California (n = 130), Colorado (n = 76), New Mexico (n = 101), Oklahoma (n = 40), Utah (n = 59), or Texas (n = 101) and handled woodrats. The total number of woodrats handled by persons in this group ranged from I (1-99) to V (10,000-49,999); the median was I (1-99).

Lymphocytic choriomeningitis virus (LCMV LCMV Lymphocytic Choriomeningitis Virus
LCMV Linearly Constrained Minimum Variance
LCMV Least Cost Matrix Value
LCMV Lightweight Counter-Mortar Radar
) is the only Old World arenavirus species that is enzootic en·zo·ot·ic
adj.
Prevalent among or restricted to animals of a specific geographic area. Used of a disease.

n.
An enzootic disease.



enzootic

peculiar to or present constantly in a location. See also endemic.
 in North America. The house mouse (Mus musculus) is a member of the subfamily subfamily /sub·fam·i·ly/ (sub´fam-i-le) a taxonomic division between a family and a tribe.

sub·fam·i·ly
n.
A taxonomic category ranking between a family and a genus.
 Murinae, family Muridae (11) and the principal host of LCMV. In this study, 526 (69.5%) persons had worked with house mice. The total number of house mice handled by persons in this group ranged from I (1-99) to VI ([greater than or equal to] 50,000); the median was I (1-99).

Of the 757 persons in this study, 735 (97.1%) had worked with rodents before the discovery of HPS in 1993; during that time, 504 (68.6%) of them never or infrequently wore personal protective equipment (gloves, a protective mask equipped with HEPA filters, and protective eyewear) when handling rodents. In contrast, only 267 (36.3%) of these 735 persons never or infrequently wore personal protective equipment when handling rodents after the discovery of HPS. Use of personal protective equipment by the other persons in the study both before and after the discovery of HPS depended on the type of equipment.

All unique identifying information was removed from the serum samples before they were tested for antibodies. Furthermore, all unique identifying information was removed from the computer (electronic) records before analysis of the demographic and serologic se·rol·o·gy  
n. pl. se·rol·o·gies
1. The science that deals with the properties and reactions of serums, especially blood serum.

2.
 data.

Antibody Assays

We tested the serum samples for immunoglobulin G immunoglobulin G
n. Abbr. IgG
The most abundant class of antibodies found in blood serum and lymph and active against bacteria, fungi, viruses, and foreign particles. Immunoglobulin G antibodies trigger action of the complement system.
 (IgG) against SNV, WWAV, GTOV, and LCMV by using ELISA ELISA (e-li´sah) Enzyme-Linked Immuno-Sorbent Assay; any enzyme immunoassay using an enzyme-labeled immunoreactant and an immunosorbent.

ELISA
n.
, as described (24, 28). The SNV antigen was an Escherichia coli-expressed recombinant SNV nucleocapsid nucleocapsid /nu·cleo·cap·sid/ (noo?kle-o-kap´sid) a unit of viral structure, consisting of a capsid with the enclosed nucleic acid.

nu·cle·o·cap·sid
n.
 protein that is highly cross-reactive with other neotomine rodent-associated hantaviruses and with sigmodontine rodent-associated hantaviruses in the ELISA used in this study (T.G. Ksiazek, unpub, data). The control (comparison) antigen for the SNV IgG ELISA IgG ELISA,
n.pr a diagnostic test for identifying reactive substances that provoke delayed hypersensitivity of the immune system. A solid-phase immunoassay that uses enzymes to test for IgG subclass reactions.
 was an E. coli-expressed recombinant protein recombinant protein Molecular biology A protein encoded by recombinant DNA or generated from a recombinant gene. See Recombinant pharmacology.  that is antigenically unrelated to the SNV nucleocapsid protein. The arenavirus antigens were detergent lysates of Vero E6 cells infected with WWAV strain AV 9310135, GTOV strain 1NH-95551, or LCMV strain Armstrong. WWAV is highly cross-reactive with BCNV and TAMV in the ELISA used in this study (M.L. Milazzo, unpub, data). Collectively, WWAV, GTOV, and LCMV represent the 3 major antigen groups in the family Arenaviridae, as defined by ELISA (19). The control antigens for the arenavirus IgG assays were detergent lysates of uninfected Vero E6 cells. The working concentrations of the SNV, GTOV, and LCMV antigens and the corresponding control antigens were determined by checkerboard checkerboard

the pattern of a chess or draft board; used in many circumstances to display the results of mixing a specific number of variables. The variables are listed in columns designated along the horizontal border and the same or different variables in lines along the vertical
 titration titration (tītrā`shən), gradual addition of an acidic solution to a basic solution or vice versa (see acids and bases); titrations are used to determine the concentration of acids or bases in solution.  against convalescent-phase serum samples from humans infected with SNV, GTOV, and LCMV, respectively. The working concentrations of the WWAV antigen and the corresponding control antigen were determined by checkerboard titration against a mouse ascitic as·ci·tes  
n. pl. ascites
An abnormal accumulation of serous fluid in the abdominal cavity.



[Middle English aschites, from Late Latin asc
 fluid against WWAV strain AV 9310135. Serial 4-fold dilutions (from 1:100 through 1:6,400) of each serum sample were tested against the 4 test antigens and 4 control antigens. Antibody bound to antigen was detected by using a goat anti-human IgG (gamma chain-specific) peroxidase peroxidase /per·ox·i·dase/ (per-ok´si-das) any of a group of iron-porphyrin enzymes that catalyze the oxidation of some organic substrates in the presence of hydrogen peroxide.

per·ox·i·dase
n.
 conjugate conjugate /con·ju·gate/ (kon´jdbobr-gat)
1. paired, or equally coupled; working in unison.

2. a conjugate diameter of the pelvic inlet; used alone usually to denote the true conjugate diameter; see
 (Kirkegaard and Perry Laboratories, Gaithersburg, MD, USA). Optical densities (OD) at 405 nm (reference = 490 nm) were measured with a Dynex MRX MRX Mission Rehearsal Exercise (US DoD)
MRX Mental Retardation, X-Linked
MRX Magneto-Resistive Extended
MRX Magnetic Resonance, Soft Spectrum Coupled X-Ray Laser
 II microplate reader (Dynatech Industries, Inc., McLean, VA, USA). The adjusted OD (AOD See HD DVD. ) of a serumantigen reaction was the OD of the well coated with the test antigen minus the OD of the well coated with the control antigen. A sample was considered positive if the AOD at 1:100 was [greater than or equal to] 0.200, the AOD at 1:400 was [greater than or equal to] 0.200, and the sum of the AODs for the series of 4-fold dilutions (from 1:100 through 1:6,400) was [greater than or equal to] 0.900. These criteria for positivity were based on the results of previous work with the test antigens and control antigens. The antibody titer antibody titer The amount of a specific antibody present in the serum, usually as a result of an acquired infection; titers for IgM usually rise abruptly at the time of infection–acute phase and fall slowly; during the 'convalescent' phase, IgG ↑ and is  of a positive sample was the reciprocal of the highest dilution of that sample for which the AOD was [greater than or equal to] 0.200.

Results

Antibodies against SNV were detected in 4 (0.5%) of the 757 persons in the study. Antibody titers were 1,600 in 2 persons and [greater than or equal to] 6,400 in the other 2 persons. The total years worked with rodents and the lifetime number of rodents handled by the 4 antibody-positive persons were 9.0-30.0 (mean 21.3) and IV (1,000-9,999) to V (10,000-49,999), respectively. Two of the antibody-positive persons had worked with rodents only within the contiguous United States (specifically Arkansas, Arizona, Colorado, Iowa, Kansas, Michigan, Oklahoma, South Carolina South Carolina, state of the SE United States. It is bordered by North Carolina (N), the Atlantic Ocean (SE), and Georgia (SW). Facts and Figures


Area, 31,055 sq mi (80,432 sq km). Pop. (2000) 4,012,012, a 15.
, and/or Texas), 1 had worked with rodents in Arizona, Colorado, New Mexico, Utah, Texas, and Mexico, and 1 had worked with rodents in Michigan, Pennsylvania, Mexico, Costa Rica, and Argentina. All 4 antibody-positive persons had handled deer mice, white-footed mice, other neotomine rodents, cotton rats, and other sigmodontine rodents. Those who had worked in South Carolina or Argentina also had handled oryzomyine rodents. All 4 antibody-positive persons reported that they had never worn a protective mask or protective eyewear when handling rodents before the discovery of HPS. One reported having been hospitalized for an illness characterized by fever, headache, and severe shortness of breath (symptoms suggestive of suggestive of Decision making adjective Referring to a pattern by LM or imaging, that the interpreter associates with a particular–usually malignant lesion. See Aunt Millie approach, Defensive medicine.  HPS). This person had worked with rodents only within the contiguous United States.

Antibodies against WWAV or GTOV were detected in 2 (0.3%) of the 757 persons in the study. Antibodies against WWAV (antibody titer = 1,600) but not GTOV were detected in a person who had worked with rodents in Texas and Wisconsin and handled woodrats, other neotomine rodents, and sigmodontine rodents. Antibodies against GTOV (antibody titer = 1,600) but not WWAV were detected in a person who had worked with rodents in Pennsylvania, Utah, and Wyoming and handled white-footed mice, other neotomine rodents, cotton rats, and other sigmodontine rodents. The lifetime number of rodents handled by the 2 antibody-positive persons were III (500-999) and IV (1,000-9,999), respectively. Both reported that they had never worn a protective mask or protective eyewear when handling rodents before the discovery of HPS. Antibodies against LCMV were found in none of the 757 persons in this study.

Discussion

Previously published studies found no antibodies against SNV in 583 persons who worked in Arizona or New Mexico in occupations that potentially exposed them to rodents or rodent droppings (29, 30) and no antibodies against SNV or WWAV in 72 persons in California whose occupations entailed close physical contact with rodents (31). Limited seroprevalence seroprevalence Immunology The proportion of a population that is seropositive–ie, has been exposed to a particular pathogen or immunogen; the seropositivity of a population is calculated as the number of individuals who produce a particular antibody divided  studies found antibodies against LCMV in up to 5.1% of healthy persons in the United States (32, 33). If one discounts fatal infections and assumes that IgG against SNV and other hantaviruses is measurable many years after recovery from infection, the results of this study indicate that the risk for infection with hantaviruses usually is low in persons whose occupations entail close physical contact with neotomine rodents or sigmodontine rodents in North America. Similarly, the study results indicate that the risk for infection with arenaviruses usually is low in persons whose occupations entail close physical contact with neotomine rodents or sigmodontine rodents in North America

Some hantaviruses and arenaviruses appear to be restricted to small areas within the geographic ranges of the rodent species that serve as their natural reservoirs. For example, BCCV and TAMV have been found only in southern Florida (4, 14), yet the geographic range of S. hispidus extends from Arizona, Nebraska, and Virginia through northeastern Mexico (11). Furthermore, the prevalence of infected rodents can vary widely even in a small area (23, 34). Thus, the low prevalence of antibodies against SNV and against the arenaviruses included in this study could be because few of the rodents handled by the 757 persons in the study were infected with a hantavirus or arenavirus. Other explanations for the low prevalence of antibodies against SNV, WWAV, GTOV, and LCMV in this study are because the circumstances under which or the manner in which the rodents were handled did not favor rodent-to-human virus transmission or because tissues, secretions, and excretions from infected rodents are not highly infectious to humans.

Antibodies against SNV were detected in 3 (0.8%) of the 387 persons in this study who had worked with rodents in Colorado, New Mexico, Utah, Arizona, Nevada, or California and who had handled deer mice. Antibodies to SNV also were detected in 1 (1.2%) of the 81 persons who had worked in New York, Pennsylvania, or Rhode Island and who had handled white-footed mice. The antibodies against SNV in the 3 antibody-positive persons who had worked in the southwestern United States could be a consequence of infection with SNV. The antibodies against SNV in the person who had worked in Pennsylvania could be a result of infection with NYV.

Of the 453 laboratory-confirmed HPS cases mentioned previously, 160 (35.3%) were fatal. Together, the high case-fatality ratio case-fatality ratio Epidemiology A value calculated as 100 cases of a disease 'X', divided by the number of persons with the disease who died in a given period of time; the resulting ratio is equal to the rate of a disease's occurrence. See Cause-fatality ratio.  of HPS in North America, the lack of a vaccine against HPS, and the lack of a specific therapy for HPS should motivate persons to minimize their risk for infection while working in the field, classroom, or laboratory with rodents potentially infected with hantaviruses, especially those viruses known to cause HPS. Published guidelines for safely working with rodents potentially infected with hantaviruses include using protective gloves, respirators fitted with HEPA filters, and protective eyewear (35). None of the 4 persons in the study who were antibody-positive against SNV had worn gloves, masks, or protective eyewear when handling rodents before the discovery of HPS.

The use of personal protective equipment in the field may seem cumbersome. However, 2 recent HPS cases, 1 fatal, underscore the need to use appropriate personal protective equipment and follow recommended safety procedures when working with rodents potentially infected with hantaviruses that have been causally associated with HPS. The fatal case was in a graduate student who was studying the effects of forest management practices on small mammal populations in West Virginia (36). The nonfatal case was in a field technician who was trapping rodents as part of a forest health study in California (37). HPS has been reported in other persons whose occupations entailed close physical contact with wild rodents (38, 39).

The person in this study who was antibody-positive against WWAV had worked with rodents in Texas and handled woodrats. Antibodies against WWAV strain AV 9310135 have been found in southern plains woodrats (Neotoma micropus) captured in western Texas and in northern Texas (M.L. Milazzo, unpub, data), and arenaviruses antigenically closely related to WWAV strain AV 9310135 have been isolated from southern plains woodrats captured in southern Texas (27, 40). Thus, the antibodies against WWAV in this person could be a result of an arenavirus infection acquired from a woodrat captured in Texas.

When examined by antibody-antigen binding assays such as the ELISA, GTOV is distinct from the 3 North American arenaviruses and highly cross-reactive with JUNV, MACV, and SABV (19). Thus, the antibodies against GTOV in the person in this study could be a result of an arenavirus infection acquired while traveling in South America. Alternatively, the antibodies could be a result of infection with a North American arenavirus that is antigenically more closely related to GTOV than to BCNV, TAMV, or WWAV.

Recently, antibodies against GTOV but not WWAV or LCMV were detected in 3 peromyscine rodents (Peromyscus sp.) captured in southern Mexico (M.L. Milazzo, unpub, data). The antibodies against GTOV in these 3 rodents are the first evidence that an arenavirus antigenically distinct from BCNV, TAMV, WWAV, and LCMV exists in North America and support the idea that the infection in the antibody-positive person in this study was a result of an arenavirus infection acquired in North America.

National Institutes of Health grant AI-41435 provided financial support for the portion of this study conducted by Mi.M. and C.F.F.

This study was approved by the Committee for the Protection of Human Subjects, Centers for Disease Control and Prevention. Written informed consent was obtained from all participants in accordance with Title 45, Part 46 of the Code of Federal Regulations The New Deal program of legislation enacted during the administration of President franklin roosevelt established a large number of new federal agencies, which generated a shapeless and confusing mass of new regulations. .

Dr Fulhorst is an associate professor at University of Texas Medical Branch "UTMB" redirects here. For other system schools, see University of Texas System.
The University of Texas Medical Branch (UTMB) is a component of the University of Texas System located in Galveston, Texas, about 50 miles (80 km) southeast of downtown Houston.
. His research interests include the epidemiology and ecology of rodentborne hantaviruses and arenavimses native to the Americas.

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abbr.
Joint Chiefs of Staff

JCS (US) n abbr (= Joint Chiefs of Staff) → Stabschefs pl 
, Buchmeier MJ, Chattel chattel (chăt`əl), in law, any property other than a freehold estate in land (see tenure). A chattel is treated as personal property rather than real property regardless of whether it is movable or immovable (see property).  RN, Gonzalez JP, Lukashevich IS, et al. 2005. Family Arenaviridae. Fauquet CM, Mayo MA, Maniloff J, Desselberger U, Ball LA, editors. Virus taxonomy: eighth report of the International Committee on Taxonomy of Viruses. San Diego: Elsevier Academic Press; 2005. p. 725-33.

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An updated Third Edition of Mammal Species of the World was published late in 2005: Wilson, D. E.
. A taxonomic and geographic reference. 3rd edition. Baltimore: Johns Hopkins University Johns Hopkins University, mainly at Baltimore, Md. Johns Hopkins in 1867 had a group of his associates incorporated as the trustees of a university and a hospital, endowing each with $3.5 million. Daniel C.  Press; 2005.

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(13.) Childs JE, Ksiazek TG, Spiropoulou CF, Krebs JW, Morzunov S, Maupin GO, et ah Serologic and genetic identification of Peromyscus maniculatus as the primary rodent reservoir for a new hantavirus in the southwestern United States. J Infect Dis. 1994;169:1271-80.

(14.) Jennings WL, Lewis AL, Sather GE, Pierce LV, Bond JO. Tamiami virus in the Tampa Bay area. Am J Trop Med Hyg. 1970;19:527-36.

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(16.) Torrez-Martinez N, Hjelle B. Enzootic of Bayou hantavirus in rice rats (Oryzomys palustris) in 1983. Lancet. 1995;346:780-1.

(17.) Torrez-Martinez N, Bharadwaj M, Goade D, Delury J, Moran P, Hicks B, et al. Bayou virus-associated hantavirus pulmonary syndrome in eastern Texas: identification of the rice rat, Oryzomys palustris, as reservoir host reservoir host
n.
A host that serves as a source of infection and potential reinfection of humans and as a means of sustaining a parasite when it is not infecting humans.
. Emerg Infect Dis. 1998;4:105-11.

(18.) Fulhorst CF, Bennett SG, Milazzo ML, Murray HL, Webb JP Jr, Bradley RD. Bear Canyon virus: an arenavirns naturally associated with Peromyscus californicus (California mouse). Emerg Infect Dis. 2002;8:717-20.

(19.) Fulhorst CF, Bowen MD, Ksiazek TG, Rollin PE, Nichol ST, Kosoy MY, et al. Isolation and characterization of Whitewater Arroyo virus, a novel North American arenavirus. Virology. 1996; 224:114-20.

(20.) Duchin JS, Koster FT, Peters C J, Simpson G, Tempest B, Zaki S. Hantavirns pulmonary syndrome: a clinical description of 17 patients with a newly recognized disease. N Engl J Med. 1994;330:949-55.

(21.) Huang C, Campbell WP, Means R, Ackman DM. Hantavirus S RNA RNA: see nucleic acid.
RNA
 in full ribonucleic acid

One of the two main types of nucleic acid (the other being DNA), which functions in cellular protein synthesis in all living cells and replaces DNA as the carrier of genetic
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(23.) Abbott KD, Milazzo ML, Keith J, Bradley RD, Fulhorst CF. Epizootiology of arenavirus infections in the white-throated woodrat (Muridae: Sigmodontinae) and other woodrats in Arizona. J Vector Ecol. 2004;29:355-64.

(24.) Bennett SG, Milazzo ML, Webb JP Jr, Fulhorst CF. Arenavirus antibody in rodents indigenous to coastal southern California. Am J Trop Med Hyg. 2000;62:626-30.

(25.) Calisher CH, Nabity S, Root JJ, Fulhorst CF, Beaty BJ. Transmission of an arenavirus in white-throated woodrats (Neotoma albigula) in southeastern Colorado, 1995-1999. Emerg Infect Dis. 2001;7:397-402.

(26.) Kosoy MY, Elliott LH, Ksiazek TG, Fulhorst CF, Rollin PE, Childs JE, et al. Prevalence of antibodies to arenaviruses in rodents from the southern and western United States: evidence for an arenavirus associated with the genus Neotoma. Am J Trop Med Hyg. 1996;54:570-6.

(27.) Fulhorst CF, Charrel RN, Weaver SC, Ksiazek TG, Bradley RD, Milazzo ML, et al. Geographical distribution and genetic diversity of Whitewater Arroyo virus in the southwestern United States. Emerg Infect Dis. 2001;7:403-7.

(28.) Ksiazek TG, Peters CJ, Rollin PE, Zaki S, Nichol S, Spiropoulou C, et al. Identification of a new North American hantavirus that causes acute pulmonary insufficiency pulmonary insufficiency
n.
Valvular insufficiency involving the pulmonary valve.
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(29.) Vitek CR, Ksiazek TG, Peters CJ, Breiman RF. Evidence against infection with hantaviruses among forest and park workers in the southwestern United States. Clin Infect Dis. 1996;23:283-5.

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(33.) Stephensen CB, Blount SR, Lanford RE, Holmes KV, Montali RJ, Fleenor ME, et al. Prevalence of serum antibodies against lymphocytic choriomeningitis virus in selected populations from two US cities. J Med Virol. 1992;38:27-31.

(34.) Childs JE, Glass GE, Korch GW, Ksiazek TG, LeDuc JW. Lymphocytic choriomeningitis virus infection and house mouse (Mus musculus) distribution in urban Baltimore. Am J Trop Med Hyg. 1992;47:27-34.

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(36.) Centers for Disease Control and Prevention. Two cases of hantavirus pulmonary syndrome--Randolph County, West Virginia, July 2004. MMWR MMWR Morbidity & Mortality Weekly Report Epidemiology A news bulletin published by the CDC, which provides epidemiologic data–eg, statistics on the incidence of AIDS, rabies, rubella, STDs and other communicable diseases, causes of mortality–eg,  Morb Mortal Wkly Rep. 2004;53:1086-9.

(37.) California Department of Health Services Department of Health Services may refer to:
  • Los Angeles County Department of Health Services
  • California Department of Health Services a California state agency
. Vector-borne disease vector-borne disease Infectious diseases Any infection, usually transmitted by insects–eg, ticks–eg, Lyme disease, Rocky Mountain spotted fever, ehrlichiosis, Colorado tick fever; mosquitos–eg, California-or La Crosse, St Louis, Eastern, Western  section. Hantavirus pulmonary syndrome in California residents. 2004 Annual Report. Sacramento (CA): California Department of Health Services; 2005. p. 4-5.

(38.) Canada Health and Welfare. First reported cases of hantavirus pulmonary syndrome in Canada. Can Commun Dis Rep. 1994;20:121-8.

(39.) Jay M, Hjelle B, Davis R, Ascher M, Baylies HN, Reilly K, et al. Occupational exposure leading to hantavirus pulmonary syndrome in a utility company employee. Clin Infect Dis. 1996;22:841-4.

(40.) Fulhorst CF, Milazzo ML, Carroll DS, Charrel RN, Bradley RD. Natural host relationships and genetic diversity of Whitewater Arroyo virus in southern Texas. Am J Trop Med Hyg. 2002; 67:114-8.

Address for correspondence: Charles F. Fulhorst, University of Texas Medical Branch, Department of Pathology, 301 University Blvd, Galveston, TX 77555-0609, USA; email: cfulhors@utmb.edu

Use of trade names is for identification only and does not imply endorsement by the Public Health Service or by the U.S. Department of Health and Human Services Noun 1. Department of Health and Human Services - the United States federal department that administers all federal programs dealing with health and welfare; created in 1979
Health and Human Services, HHS
.

(1) Current affiliation: Yale University School of Medicine, New Haven, Connecticut, USA

(2) Current affiliation: University of Texas Medical Branch, Galveston, Texas, USA

Charles F. Fulhorst, * Mary Louise Milazzo, * Lori R. Armstrong, ([dagger]) James E. Childs, ([dagger], 1) Pierre E. Rollin, ([dagger]) Rima Khabbaz, ([dagger]) C.J. Peters, ([dagger],2) and Thomas G. Ksiazek ([dagger])

* University of Texas Medical Branch, Galveston, Texas, USA; and

([dagger]) Centers for Disease Control and Prevention, Atlanta, Georgia, USA
Table 1. Occupational exposure of 726 persons to sigmodontine
or neotomine rodents within the contiguous United States

State                        No. persons exposed *

Alabama                 16 ([dagger])
Arkansas                33
Arizona                 92 ([dagger])([double dagger])
California             178 ([dagger]([double dagger])
Colorado               128 ([dagger])([double dagger])
Connecticut             19
Delaware                 1
Florida                 17 ([dagger])([double dagger])
Georgia                 15
Idaho                   21 ([dagger])
Illinois                38 ([dagger])
Indiana                 26 ([dagger])
Iowa                    17 ([dagger])
Kansas                  90 ([dagger])
Kentucky                 6
Louisiana               11 ([dagger])
Maine                   21
Massachusetts           17
Maryland                27
Michigan                38
Minnesota               21 ([dagger])
Mississippi              6
Missouri                36
Montana                 21 ([dagger])
Nebraska                25 ([dagegr])
Nevada                  39 ([dagger])
New Hampshire            6
New Jersey               9
New Mexico             118 ([dagger]([double dagger])
New York                46 ([dagger])
North Carolina          15 ([dagger])
North Dakota             9 ([dagger])
Ohio                    25
Oklahoma                41 ([dagger]([double dagger])
Oregon                  45 ([dagger])
Pennsylvania            45 ([dagger])
Rhode Island             5
South Carolina          16
South Dakota            11 ([dagger])
Tennessee               23
Texas                  112 ([dagger])([double dagger])
Utah                    67 ([dagger])([double dagger])
Vermont                  6 ([dagger])
Virginia                49 ([dagger])
Washington              73 ([dagger])
West Virginia           11 ([dagger])
Wisconsin               22 ([dagger])
Wyoming                 41 ([dagger])
District of Columbia     2

* No. persons who worked with rodents in the state or in the District
of Columbia. Of the persons in the study, 468 had worked with rodents
in >1 state within the contiguous United States.

([dagger]) States that have reported [greater than or equal to] case
of hantavirus pulmonary syndrome to the Centers for Disease Control
and Prevention through September 19, 2006 (see
www.cdc.gov/ncidod/diseases/hanta/hps/noframes/epislides/episl7.htm).

([double dagger]) States in which neotomine or sigmodontine rodents
are known to be naturally associated with Bear Canyon virus, Tamiami
virus, or Whitewater Arroyo virus.

Table 2. Work-related exposure of 757 persons to neotomine and
sigmodontine rodents

                                                        Exposure
                                                   ([double dagger])

No. persons *         Rodent ([dagger])              Range   Median

695          Deer mouse (Peromyscus maniculatus)     I-VI      II
487            White-footed mouse (P. leucopus)      I-VI      II
34            California mouse (P. californicus)     I-III      I
456                 Woodrat (Neotoma spp.)           I-V        I
392                Other neotomine rodents           I-IV       I
511               Cotton rat (Sigmodon spp.)         I-VI       I
51                    Oryzomyine rodents             I-IV       I

* No. persons who self-reported occupational exposure to rodents.

([dagger]) Other neotomine rodents included the pygmy mouse (Baiomys
spp.), Texas mouse (Peromyscus attwateri), brush mouse (P. boylii),
canyon mouse (P. crinitus), Zacatecan deer mouse (P. difficilis),
cactus mouse (P. eremicus), Florida mouse (P. floridanus), cotton mouse
(P. gossypinus), northern rock mouse (P. nasutus), golden mouse
(P. nuttalis), white-ankled mouse (P. pectoralis), oldfield mouse
(P. polionotus), pinyon mouse (P. truei), and western harvest mouse
(Reithrodontomys megalotis) and other harvest mice (Reithrodontomys
spp.). Oryzomyine rodents included the marsh rice rat (Oryzomys
palustris), other oryzomine rodents (Oryzomys spp.), and oligoryzomine
rodents (Oligoryzomys spp.).

([double dagger]) The number of rodents handled by a study subject was
categorized as follows: I, 1-99; II, 100-499; III, 500-999; IV,
1,000-9,999; V, 10,000-49,999; VI, [greater than or equal to] 50,000.
COPYRIGHT 2007 U.S. National Center for Infectious Diseases
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 2007, Gale Group. All rights reserved. Gale Group is a Thomson Corporation Company.

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Title Annotation:RESEARCH
Author:Ksiazek, Thomas G.
Publication:Emerging Infectious Diseases
Date:Apr 1, 2007
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