Vector-borne diseases are transmitted from one animal to another by vectors, including insects, such as mosquitoes or fleas, and arachnids, such as ticks. The USGS National Wildlife Health Center investigates wildlife diseases, including vector-borne diseases, such as West Nile virus and sylvatic plague.
The following are vector-borne diseases currently being studied by the USGS National Wildlife Health Center (NWHC).
West Nile Virus
West Nile virus, a mosquito-transmitted virus, was introduced into the New York City area of North America in 1999. Since then the virus has been transmitted throughout the continental U.S., southern Canadian Provinces, Mexico. The virus has also been transmitted on the Caribbean islands, Central and South America. West Nile virus causes disease symptoms, including encephalitis, in humans and horses, but has been devastating to North American wild bird populations, particularly the corvids, raptors, and songbirds. Population declines in members of these bird groups have been documented and linked to the year West Nile virus emerged in states or geographic areas of the U.S.
The NWHC has been involved with West Nile virus surveillance in wild birds and research since the entry of the virus into the U.S. In recent years we have assisted states and Tribes in monitoring for virus transmission in ruffed grouse (Bonasa umbellus), snow shoe hares (Lepus americanus), and wild wolves (Canus lupus). Experimentally, the NWHC has been working to develop models of West Nile virus susceptibility in passerine, or song birds, using domesticated zebra finches (Taeniopygia guttata) and canaries (Serinus canaria), which show lower and higher susceptibility to the virus, respectively. Since the genome of these domesticated birds has been published studies on molecular basis of disease susceptibility are possible.
West Nile virus continues to circulate every summer in the U.S. An uptick in human, domestic animal, and avian cases, might be related to weather, with hot and dry conditions being permissive, and also cycles of immunity in birds, the primary host for the virus.
To see disease reports of West Nile virus, search WHISPers (Wildlife Health Information Sharing Partnership event reporting system.
To check out historic fact sheets on West Nile virus, see – NWHC Fact Sheets.
Sylvatic Plague
Sylvatic plague, caused by Yersinia pestis, is a bacterial disease transmitted by fleas that afflicts many mammalian species, including humans. For many species of wildlife, plague mortality is a serious conservation issue. Current efforts to halt the spread of plague in prairie dog colonies typically rely on dusting individual prairie dog burrows with pesticides to kill plague-infected fleas. Although flea-control insecticides, such as deltamethrin, are useful in stopping plague outbreaks in these prairie dog colonies, dusting of burrows is labor intensive and time consuming and may affect other insects and arthropods.
Scientists at the USGS National Wildlife Health Center (NWHC), in collaboration with colleagues at the University of Wisconsin (UW), have developed a sylvatic plague vaccine that shows great promise in protecting prairie dogs against plague. Controlling plague is a vital concern for ongoing management and conservation efforts for prairie dogs.
To learn more about sylvatic plague and read related publications, see – Sylvatic Plague and Vaccines.
Below are other science projects related to vector-borne diseases.
Vaccines
Sylvatic Plague
Below are FAQs associated related to vector-borne diseases.
Are birds the only species that is susceptible to West Nile Virus infection?
West Nile Virus (WNV) has been detected in at least 48 species of mosquitoes, over 320 species of birds, at least 2 species of reptiles, and more than 25 mammalian species, including horses and humans. Birds are the natural host and reservoir of WNV. Although other animals are susceptible to WNV infection, only birds develop a high enough virus load to transmit the infection to an uninfected...
Can hunters get West Nile Virus from eating infected game birds?
Some game birds have tested positive for West Nile Virus (WNV). However, there is no evidence of human infection by consumption of properly cooked infected game. Hunters are likely at higher risk of infection by mosquito exposure, particularly in wetland environments. Protective measures should be taken to prevent mosquito exposure while hunting. There are extremely rare cases of laboratory...
Can my dog or cat get West Nile Virus by eating an infected animal?
Experimentally, it was found that this might be possible. However, there has been no evidence to indicate that West Nile Virus can be naturally transmitted to cats or dogs that carry or consume infected animals. Dogs and cats can be infected with West Nile Virus through the bite of a mosquito, so minimizing their exposure to mosquitoes is recommended.
How do I handle a sick or dead animal that might have West Nile Virus?
Under normal conditions, humans are unlikely to be infected with West Nile Virus by handling a sick or dead animal. However, there are a number of other infections that could potentially result from handling an animal. To protect yourself from exposure to any illness, you should wear gloves or put a plastic bag over your hand before touching the animal and you should wash your hands with soap and...
How do I know if an animal is infected with West Nile Virus?
Signs of infection in wildlife, like in humans, can range from no symptoms to severe symptoms of neurologic illness. Commonly reported signs in animals include weakness, stumbling, trembling, head tremors, inability to fly/walk, and a lack of awareness that allows them to be easily approached and handled. These symptoms, however, can also have other causes. The only way to positively confirm West...
Is there a West Nile Virus vaccine available for birds?
At this time, there is not a West Nile Virus vaccine approved for use in birds. The Centers for Disease Control and Prevention, in collaboration with several organizations and laboratories, is developing and testing vaccines for use in birds. Many zoos and wildlife centers have been using the Fort Dodge horse vaccine (West Nile-Innovator®) in birds. The vaccine has not been tested for use in birds...
What is the threat from West Nile Virus (WNV) to endangered and threatened bird species?
This is an issue of great concern, as these populations are already struggling to survive in the current environment. If some of these species are more vulnerable to fatal WNV infection, WNV may ultimately lead to their extinction or significantly set back the progress of the recovery programs.
Where in the United States has West Nile Virus been detected in wildlife?
West Nile Virus has been detected in all conterminous states of the U.S., the District of Columbia, and Puerto Rico. Alaska, Hawaii, and Guam have no reported cases of West Nile virus in humans or animals. Distribution maps are available from the Centers for Disease Control. Learn more: Vector-Borne Diseases
- Overview
Vector-borne diseases are transmitted from one animal to another by vectors, including insects, such as mosquitoes or fleas, and arachnids, such as ticks. The USGS National Wildlife Health Center investigates wildlife diseases, including vector-borne diseases, such as West Nile virus and sylvatic plague.
The following are vector-borne diseases currently being studied by the USGS National Wildlife Health Center (NWHC).
West Nile Virus
West Nile virus, a mosquito-transmitted virus, was introduced into the New York City area of North America in 1999. Since then the virus has been transmitted throughout the continental U.S., southern Canadian Provinces, Mexico. The virus has also been transmitted on the Caribbean islands, Central and South America. West Nile virus causes disease symptoms, including encephalitis, in humans and horses, but has been devastating to North American wild bird populations, particularly the corvids, raptors, and songbirds. Population declines in members of these bird groups have been documented and linked to the year West Nile virus emerged in states or geographic areas of the U.S.
Sources/Usage: Public Domain.Mosquito, species not verified(Public domain.) The NWHC has been involved with West Nile virus surveillance in wild birds and research since the entry of the virus into the U.S. In recent years we have assisted states and Tribes in monitoring for virus transmission in ruffed grouse (Bonasa umbellus), snow shoe hares (Lepus americanus), and wild wolves (Canus lupus). Experimentally, the NWHC has been working to develop models of West Nile virus susceptibility in passerine, or song birds, using domesticated zebra finches (Taeniopygia guttata) and canaries (Serinus canaria), which show lower and higher susceptibility to the virus, respectively. Since the genome of these domesticated birds has been published studies on molecular basis of disease susceptibility are possible.
West Nile virus continues to circulate every summer in the U.S. An uptick in human, domestic animal, and avian cases, might be related to weather, with hot and dry conditions being permissive, and also cycles of immunity in birds, the primary host for the virus.
To see disease reports of West Nile virus, search WHISPers (Wildlife Health Information Sharing Partnership event reporting system.
To check out historic fact sheets on West Nile virus, see – NWHC Fact Sheets.
Sylvatic Plague
Sylvatic plague, caused by Yersinia pestis, is a bacterial disease transmitted by fleas that afflicts many mammalian species, including humans. For many species of wildlife, plague mortality is a serious conservation issue. Current efforts to halt the spread of plague in prairie dog colonies typically rely on dusting individual prairie dog burrows with pesticides to kill plague-infected fleas. Although flea-control insecticides, such as deltamethrin, are useful in stopping plague outbreaks in these prairie dog colonies, dusting of burrows is labor intensive and time consuming and may affect other insects and arthropods.
Sources/Usage: Public Domain.National Park Service veterinarian Kevin Castle checks an anaesthetized prairie dog for fleas in Wind Cave National Park. Over 30 organizations and agencies are testing a USGS-developed oral vaccine to prevent the spread of plague in prairie dogs. If successful, the sylvatic plague vaccine could help protect endangered black-footed ferrets in the western U.S. because the ferrets rely on prairie dogs for food. Castle tags each trapped prairie dog and takes hair, whisker, and blood samples before scientists release the animals back into the wild.(Credit: Marisa Lubeck, U.S. Geological Survey. Public domain.) Scientists at the USGS National Wildlife Health Center (NWHC), in collaboration with colleagues at the University of Wisconsin (UW), have developed a sylvatic plague vaccine that shows great promise in protecting prairie dogs against plague. Controlling plague is a vital concern for ongoing management and conservation efforts for prairie dogs.
To learn more about sylvatic plague and read related publications, see – Sylvatic Plague and Vaccines.
- Science
Below are other science projects related to vector-borne diseases.
Vaccines
The USGS National Wildlife Health Center (NWHC) works on developing various disease management tools, including the development of vaccines. Our current work focuses on vaccines for sylvatic plague, white-nose syndrome, and rabies as disease control strategies.Sylvatic Plague
Sylvatic plague, caused by Yersinia pestis, is a bacterial disease transmitted by fleas that afflicts many mammalian species, including humans. - Publications
- News
- FAQ
Below are FAQs associated related to vector-borne diseases.
Are birds the only species that is susceptible to West Nile Virus infection?
West Nile Virus (WNV) has been detected in at least 48 species of mosquitoes, over 320 species of birds, at least 2 species of reptiles, and more than 25 mammalian species, including horses and humans. Birds are the natural host and reservoir of WNV. Although other animals are susceptible to WNV infection, only birds develop a high enough virus load to transmit the infection to an uninfected...
Can hunters get West Nile Virus from eating infected game birds?
Some game birds have tested positive for West Nile Virus (WNV). However, there is no evidence of human infection by consumption of properly cooked infected game. Hunters are likely at higher risk of infection by mosquito exposure, particularly in wetland environments. Protective measures should be taken to prevent mosquito exposure while hunting. There are extremely rare cases of laboratory...
Can my dog or cat get West Nile Virus by eating an infected animal?
Experimentally, it was found that this might be possible. However, there has been no evidence to indicate that West Nile Virus can be naturally transmitted to cats or dogs that carry or consume infected animals. Dogs and cats can be infected with West Nile Virus through the bite of a mosquito, so minimizing their exposure to mosquitoes is recommended.
How do I handle a sick or dead animal that might have West Nile Virus?
Under normal conditions, humans are unlikely to be infected with West Nile Virus by handling a sick or dead animal. However, there are a number of other infections that could potentially result from handling an animal. To protect yourself from exposure to any illness, you should wear gloves or put a plastic bag over your hand before touching the animal and you should wash your hands with soap and...
How do I know if an animal is infected with West Nile Virus?
Signs of infection in wildlife, like in humans, can range from no symptoms to severe symptoms of neurologic illness. Commonly reported signs in animals include weakness, stumbling, trembling, head tremors, inability to fly/walk, and a lack of awareness that allows them to be easily approached and handled. These symptoms, however, can also have other causes. The only way to positively confirm West...
Is there a West Nile Virus vaccine available for birds?
At this time, there is not a West Nile Virus vaccine approved for use in birds. The Centers for Disease Control and Prevention, in collaboration with several organizations and laboratories, is developing and testing vaccines for use in birds. Many zoos and wildlife centers have been using the Fort Dodge horse vaccine (West Nile-Innovator®) in birds. The vaccine has not been tested for use in birds...
What is the threat from West Nile Virus (WNV) to endangered and threatened bird species?
This is an issue of great concern, as these populations are already struggling to survive in the current environment. If some of these species are more vulnerable to fatal WNV infection, WNV may ultimately lead to their extinction or significantly set back the progress of the recovery programs.
Where in the United States has West Nile Virus been detected in wildlife?
West Nile Virus has been detected in all conterminous states of the U.S., the District of Columbia, and Puerto Rico. Alaska, Hawaii, and Guam have no reported cases of West Nile virus in humans or animals. Distribution maps are available from the Centers for Disease Control. Learn more: Vector-Borne Diseases