A female mosquito (Aedes japonicus) reared from larvae collected from the Kawaikoi Stream, Kauai.
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 Nile Virus infection is by laboratory testing of the animal’s tissues.
Learn more: Vector-Borne Diseases
Related Content
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 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...
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...
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...
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
What is Avian Influenza?
Avian influenza (AI) is caused by an influenza type A virus that can infect poultry such as chickens, turkeys, pheasants, quail, domestic ducks, geese, and guinea fowl. It is carried by wild waterfowl (ducks and geese) and shorebirds. Learn more: USGS Avian Influenza
What causes chronic wasting disease?
Chronic wasting disease is caused by a misfolded protein called a prion. All mammals produce normal prions that are used by cells, then degraded and eliminated, or recycled, within the body. When disease-associated prions contact normal prions, they cause them to refold into their own abnormal shape. These disease-associated prions are not readily broken down and tend to accumulate in--and damage-...
What is White-nose Syndrome?
White-nose syndrome is an emergent disease of hibernating bats that has spread from the northeastern to the central United States at an alarming rate. Since the winter of 2007-2008, millions of insect-eating bats in at least 40 states and eight Canadian provinces have died from this devastating disease. The disease is named for the white fungus, Pseudogymnoascus destructans , that infects skin of...
Female mosquito (Aedes japonicus) reared from larvae
A female mosquito (Aedes japonicus) reared from larvae collected from the Kawaikoi Stream, Kauai.
Biting Mosquito
Culex species mosquito biting a human hand.
Culex species mosquito biting a human hand.
USGS Analyst Performs DNA Extractions in a Laboratory
A U.S. Geological Survey analyst performs DNA extractions on enriched cultures of water from the study area. Once the DNA was extracted it was used to detect pathogen gene markers using polymerase chain reaction (PCR).
A U.S. Geological Survey analyst performs DNA extractions on enriched cultures of water from the study area. Once the DNA was extracted it was used to detect pathogen gene markers using polymerase chain reaction (PCR).
USGS Scientist Set Mistnets for West Nile Virus Monitoring
USGS scientists capture and release wild birds while monitoring for West Nile.
USGS scientists capture and release wild birds while monitoring for West Nile.
Related Content
- FAQ
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 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...
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...
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...
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
What is Avian Influenza?
Avian influenza (AI) is caused by an influenza type A virus that can infect poultry such as chickens, turkeys, pheasants, quail, domestic ducks, geese, and guinea fowl. It is carried by wild waterfowl (ducks and geese) and shorebirds. Learn more: USGS Avian Influenza
What causes chronic wasting disease?
Chronic wasting disease is caused by a misfolded protein called a prion. All mammals produce normal prions that are used by cells, then degraded and eliminated, or recycled, within the body. When disease-associated prions contact normal prions, they cause them to refold into their own abnormal shape. These disease-associated prions are not readily broken down and tend to accumulate in--and damage-...
What is White-nose Syndrome?
White-nose syndrome is an emergent disease of hibernating bats that has spread from the northeastern to the central United States at an alarming rate. Since the winter of 2007-2008, millions of insect-eating bats in at least 40 states and eight Canadian provinces have died from this devastating disease. The disease is named for the white fungus, Pseudogymnoascus destructans , that infects skin of...
- Multimedia
Female mosquito (Aedes japonicus) reared from larvae
A female mosquito (Aedes japonicus) reared from larvae collected from the Kawaikoi Stream, Kauai.
A female mosquito (Aedes japonicus) reared from larvae collected from the Kawaikoi Stream, Kauai.
Biting MosquitoCulex species mosquito biting a human hand.
Culex species mosquito biting a human hand.
USGS Analyst Performs DNA Extractions in a LaboratoryA U.S. Geological Survey analyst performs DNA extractions on enriched cultures of water from the study area. Once the DNA was extracted it was used to detect pathogen gene markers using polymerase chain reaction (PCR).
A U.S. Geological Survey analyst performs DNA extractions on enriched cultures of water from the study area. Once the DNA was extracted it was used to detect pathogen gene markers using polymerase chain reaction (PCR).
USGS Scientist Set Mistnets for West Nile Virus MonitoringUSGS scientists capture and release wild birds while monitoring for West Nile.
USGS scientists capture and release wild birds while monitoring for West Nile.
- Publications