Eastern equine encephalitis fact sheet 180200919 eastern equine encephalitis eee is a rare disease that is spread to humans and horses by infected mosquitoes. History and enhanced surveillance in ontario 1 introduction eastern equine encephalitis virus eeev is a mosquitoborne virus togaviridae. Eastern equine encephalomyelitis eee, western equine encephalomyelitis wee, and venezuelan equine encephalomyelitis vee viruses are mosquitoborne pathogens that can cause nonspecific illnesses and encephalitis in equids horses, mules, burros, donkeys and zebras and humans in the americas. Eastern equine encephalitis and horses introduction eastern equine encephalitis eee and western equine encephalitis wee virus infections occur in horses and other equids in louisiana. There are four main causes of arboviral encephalitis in the u. The cause of eastern equine encephalitis eee was first identified in the 1930s. Eastern equine encephalitis virus neuroinvasive disease cases reported by year, 1964 2010 neuroinvasive disease includes cases reported as encephalitis, meningoencephalitis, or meningitis. A the virus that causes eastern equine encephalitis is spread. Eastern equine encephalitis is one of several mosquitoborne diseases that have been seen in minnesota. Only a few cases of eeev disease are reported in the. Eastern equine encephalitis eee is a rare but serious disease caused by a virus. Eastern equine encephalitis is a rare disease that is spread to horses and humans by infected mosquitoes. Eastern equine encephalitis fact sheet minnesota department.
Eastern equine encephalitis virus quick facts eastern equine encephalitis virus eeev is an arthropodborne virus arbovirus that is primarily transmitted in indiana by mosquitoes in the genus coquillettidia. Utcvm large animal clinical sciences eastern equine. Eastern equine encephalitis virus in the united states, 2003. These include eastern equine encephalitis, western equine encephalitis, st. Eastern equine encephalitis virus eee is an arbovirus which is a mosquitoborne virus. Eastern equine encephalitis virus eeev is transmitted to humans through the bite of an infected mosquito. Eee virus is a rare cause of brain infections encephalitis. Between three and fifteen cases of eee were reported every year in the u. Cryoem structure of eastern equine encephalitis virus in.
Eastern equine encephalitis mexico pdf ppt case reports. Eastern, western and venezuelan equine encephalomyelitis result from infection by the respectively named. Eastern equine encephalomyelitis eee, western equine encephalomyelitis wee, and venezuelan equine encephalomyelitis vee viruses are mosquitoborne pathogens that can cause nonspecific illnesses and encephalitis in equids horses. Eastern equine encephalitis produces focal radiographic signs. Eastern equine encephalitis eee, also known as sleeping sickness, is a viral disease of horses that involves transmission between birds or rodents and mosquitoes.
It circulates between bird reservoir hosts and mosquitoes. Eastern equine encephalitis virus eeev disease agent characteristics. This virus is most commonly seen in horses in the southeastern us with several hundred cases reported each year. Eastern equine encephalitis, western equine encephalitis.
People infected with eeev can develop severe inflammation in the brain. Of those who contract the eee virus, the elderly ages 50 and older and young ages 15 and younger are at the greatest risk of developing encephalitis. All it takes is one bite from an infected mosquito to get eee be aware of your risk. Request pdf eastern equine encephalitis virus in the united states, 20032016 eastern equine encephalitis virus eeev is a mosquitoborne alphavirus found in the eastern united states. Anthrax to arboviral diseases, eastern equine encephalitis virus disease 2019. Only a few cases are reported in the united states each year. Eastern equine encephalitis eee is a rare illness in humans and only a few. Most illnesses occur in the northeastern atlantic states or the gulf coast states. Questions about eastern equine encephalitis and horses. Eastern equine encephalitis is a viral illness that is transmitted to people and horses through the bite of an infected mosquito.
Eeev can also infect a wide range of animals including mammals, birds, reptiles, and amphibians. We describe a patient who died from a fulminant presentation of encephalitis. A eastern equine encephalitis is a rare but serious disease caused by the bite of an infected mosquito. Eastern equine encephalitis virus eeev is an important pathogenic alphavirus that causes severe encephalitis and neuron damage with a high mortality rate of. Eastern equine encephalitis eee fact sheet what is eastern equine encephalitis. Eastern equine encephalitis, also known as triple e, is a dangerous mosquitoborne virus that infects not just horses, but humans, pigs, rodents, whitetailed deer, and a variety of wild birds. In massachusetts, the virus is most often identified in mosquitoes found in and around freshwater, hardwood swamps. Eastern equine encephalitis virus public health ontario. Eastern equine encephalitis eee and venezuelan equine encephalitis vee viruses, alphaviruses that are members of the togaviridae family, are important causes of febrile illness and encephalitis in the americas. Perspective from the new england journal of medicine eastern equine encephalitis virus another emergent arbovirus in the united states. Until recently, eastern equine encephalomyelitis virus eeev contained four. Eastern equine encephalitis virus eeev is a virus that can cause swelling of the brain encephalitis.
Human eeev cases occur relatively infrequently, largely because the primary transmission cycle takes place in and around swampy areas where human populations tend to be limited. It is among the most serious of a group of mosquitoborne virus diseases that can affect the central nervous system and cause severe complications and even death. Eastern equine encephaliuties can infect humans, birds, mosquitoes, horses and some other mammals. Eastern equine encephalitis is a rare disease that is caused by a virus spread by infected mosquitoes.
Jackson county, mi a portion of grass lake and concord townships may be sprayed tonight, october 3, to control for mosquitoes that carry eastern equine encephalitis, or eee. Eastern equine encephalitis in latin america n engl j med 369. We have identified several clinical pearls that may assist others in making the diagnosis earlier in the disease course. Eastern equine encephalitis eee, also known as sleeping sickness, is a viral disease of horses that involves transmission between birds or rodents and.
Postmortem pcr analysis of brain tissue led to a diagnosis of eastern equine encephalitis. The characteristic early involvement of the basal ganglia and thalami distinguish this illness from herpes simplex encephalitis. Preventing mosquitoborne diseases learn how to minimize your risk to eastern equine encephalitis and other diseases transmitted by mosquitoes. In 1999, there was an outbreak of west nile encephalitis in the new york area. Mmwr morb mortal wkly rep 2020 jan 17 the largest outbreak of eeev since the 1930s occurred in 2019, with a high case fatality rate especially among elderly males. Eastern equine encephalitis cornell wildlife health lab. Eastern equine encephalitis eee is an uncommon but serious disease caused by eee virus. Aug 22, 20 eastern equine encephalitis eee and venezuelan equine encephalitis vee viruses, alphaviruses that are members of the togaviridae family, are important causes of febrile illness and encephalitis in the americas. Locally acquired eastern equine encephalitis virus disease. The rapidity of deterioration and eventual outcome of infection vary among individual horses. The virus is an alphavirus and is closely related to western equine encephalitis and venezuelan equine encephalitis viruses. Eastern equine encephalitis in horses symptoms, causes. From 1964 to 1995, 151 cases were reported in the u.
It is among the most serious in a group of mosquitoborne viral diseases that can affect the central nervous system and cause severe complications and even death. A few cases of eee have been diagnosed in indiana, all in the northern tier of counties in association with swamps. To test the hypothesis that alphavirus heterologous antibodies crossprotect, animals. Currently, no approved antiviral agents are available for treatments of eeev infection. Skip directly to site content skip directly to page options skip directly to az link centers for disease control and prevention. The virus can be transmitted to horses, other animals, and in rare cases, people. Eastern equine encephalitis and horses louisiana mosquito. Encephalitis viruses are spread by mosquitoes and can affect the. Eastern equine encephalitis eee is a rare illness in humans and only a few cases are reported in the united states each year. Aerial mosquito spraying in grass lake and concord townships. Infected horses cannot transmit the disease to other horses. Early events in the pathogenesis of eastern equine.
Public health fact sheet eee eastern equine encephalitis. Eastern equine encephalitis virus eeev causes severe neurologic disease in north america, but only two fatal human cases have been documented in south america. Most infected animals and people have inapparent infections, but eee can cause mortality in some species of birds such as pigeons, pheasants, and emus. Eastern equine encephalitis virus another emergent. Eastern equine encephalitis eee, commonly called triple e or sleeping sickness not to be confused with african trypanosomiasis, is a disease caused by a zoonotic mosquito vectored togavirus that is present in north, central, and south america, and the caribbean. The virus infects birds that live in freshwater swamps and is spread from bird to bird by infected mosquitoes. Eastern equine encephalitis eee new hampshire department of. Eastern equine encephalitis is a rare but severe illness spread by the bite of an infected mosquito.
Eastern equine encephalitis eastern equine encephalitis. Eastern equine encephalitis virus in the united states, 20032016. In this table, provisional cases of notifiable diseases are displayed. The american journal of tropical medicine and hygiene 98. Eastern equine encephalomyelitis eee is a mosquitobborne viral disease of all equine species such as horses, asses, and zebras. Eastern equine encephalitis eee p rotect yourself and your family from mosquito bites that spread the virus. Morbidity rate is 7595% and death usually occurs within 23 days of onset of signs. Eastern equine encephalitis eee is a highly lethal zoonotic disease caused by eastern equine encephalitis virus eeev, an rna virus of the gen. Eastern equine encephalitis fact sheet pdf what is eastern equine encephalitis. Eastern equine encephalitis faqs disease surveillance. Eastern equine encephalitis eee is a rare but serious viral disease spread by mosquitoes that can affect people and horses. Eastern equine encephalitis, eastern equine encephalomyelitits or eee. Eastern equine encephalitis eee is more common and tends to occur in outbreak form.
This virus can be transmitted to horses, other animals, and, in rare cases, people. Counties are shaded according to incidences ranging from less than 0. After an exhaustive search, we found no treatable cause. The virus that causes eee is spread through the bite of an infected mosquito.
Enveloped, icosahedral nucleocapsid symmetry, spherical particle, 6065 nm in diameter nucleic acid. Supportive care is administered in horses which show clinical signs. Eee can also cause disease in captive birds such as the ringnecked pheasant, emu, ostriches, quail and ducks. Eastern equine encephalitis florida department of health. A few cases of eee have been diagnosed in indiana, all in. Eastern equine encephalitis eee virus is a singlestranded rna virus in the genus alphavirus family togaviridae that can cause a severe mosquitoborne encephalitis in humans, horses, and game birds.
Pdf endemic eastern equine encephalitis in the amazon. These diseases are transmitted to horses and humans by mosquitoes. Eastern equine encephalitis a large outbreak stephen g. Alphavirus found throughout the western hemisphere. In north america, eeev is restricted to areas east of the mississippi river in the us and southeastern canada. Eastern equine encephalitis virus is maintained in north america in resident birds in freshwater marshes by the ornithophilic mosquito, culiseta melanura. Eastern equine encephalitis eee is an extremely rare but serious and often fatal infection that causes encephalitis or inflammation of the brain. In wisconsin, it can be spread by different types of mosquitoes. This mosquito is responsible for amplification of the virus during the spring and summer by transmission among viremic wading birds, passerine songbirds, and starlings that are asymptomatic reservoir hosts of the virus fig. Only three human cases of eastern equine encephalitis were reported in wisconsin from 1964 to 2018. This map shows the distribution of eastern equine encephalitis virus neuroinvasive disease average annual incidence by county of residence from 2009 through 2018. It is a mosquitoborne disease, meaning that it is spread by the bite of an infected mosquito. Utcvm large animal clinical sciences eastern equine encephalitis.