Posts
Fifth case of deadly EEE virus confirmed in Massachusetts, 3 dozen communities at 'critical risk'.
The Massachusetts Department of Public Health (DPH) announced that laboratory testing has confirmed another new case of Eastern Equine Encephalitis (EEE) virus infection, a man in his 70s from southwestern Middlesex County, bringing the total number of human cases of EEE to five this year in Massachusetts. As a result, the risk level in Ashland, Hopedale and Milford has been raised to critical and the risk level in Bellingham, Blackstone and Millville has been raised to high.
In total, there are 32 communities now at critical risk, 39 at high risk, and 121 at moderate risk for the EEE virus in Massachusetts.
There have also been nine confirmed cases of EEE this year in animals; eight horses and one goat.
EEE virus is a rare cause of brain infections (encephalitis). Only a few cases are reported in the United States each year. Most occur in eastern or Gulf Coast states. Approximately 30% of people with EEE die and many survivors have ongoing neurologic problems.
Systemic infection has an abrupt onset and is characterized by chills, fever, malaise, arthralgia, and myalgia. The illness lasts 1 to 2 weeks, and recovery is complete when there is no central nervous system involvement. In infants, the encephalitic form is characterized by abrupt onset; in older children and adults, encephalitis is manifested after a few days of systemic illness. Signs and symptoms in encephalitic patients are fever, headache, irritability, restlessness, drowsiness, anorexia, vomiting, diarrhea, cyanosis, convulsions, and coma.
Approximately a third of all people with EEE die from the disease. Death usually occurs 2 to 10 days after onset of symptoms but can occur much later. Of those who recover, many are left with disabling and progressive mental and physical sequelae, which can range from minimal brain dysfunction to severe intellectual impairment, personality disorders, seizures, paralysis, and cranial nerve dysfunction. Many patients with severe sequelae die within a few years.
EEEV is difficult to isolate from clinical samples; almost all isolates (and positive PCR results) have come from brain tissue or CSF. Serologic testing remains the primary method for diagnosing EEEV infection. Combined with a consistent clinical presentation in an endemic area, a rapid and accurate diagnosis of acute neuroinvasive EEEV disease can be made by the detection of EEEV-specific IgM antibody in serum or CSF. EEEV IgM tests are available commercially, in some state health department laboratories, and at CDC. A positive EEEV IgM test result should be confirmed by neutralizing antibody testing of acute- and convalescent-phase serum specimens at a state public health laboratory or CDC. To submit specimens for testing at CDC, please contact your state health department.
All EEEV disease cases should be reported to local public health authorities. Reporting can assist local, state and national authorities to recognize outbreaks of this rare disease and to institute control measures to limit future infections.
Eastern equine encephalitis virus (EEEV) is transmitted to humans through the bite of an infected mosquito. 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. All residents of and visitors to areas where EEEV activity has been identified are at risk of infection. People who engage in outdoor work and recreational activities in endemic areas are at increased risk of infection. Persons over age 50 and under age 15 seem to be at greatest risk for developing severe disease when infected with EEEV. Overall, only about 4-5% of human EEEV infections result in EEE. EEEV infection is thought to confer life-long immunity against re-infection. It does not confer significant cross-immunity against other alphaviruses (e.g., western equine encephalitis virus), and it confers no cross-immunity against flaviviruses (e.g., West Nile virus) or bunyaviruses (e.g., La Crosse virus).
In the United States, an average of 7 human cases of EEE are reported annually. To ensure standardization of reporting across the country, CDC recommends that the national surveillance case definition be consistently applied by all state health departments.
Most cases of EEE have been reported from Florida, Massachusetts, New York, and North Carolina. EEEV transmission is most common in and around freshwater hardwood swamps in the Atlantic and Gulf Coast states and the Great Lakes region.
CDC
Massachusetts Department of Health
The Massachusetts Department of Public Health (DPH) announced that laboratory testing has confirmed another new case of Eastern Equine Encephalitis (EEE) virus infection, a man in his 70s from southwestern Middlesex County, bringing the total number of human cases of EEE to five this year in Massachusetts. As a result, the risk level in Ashland, Hopedale and Milford has been raised to critical and the risk level in Bellingham, Blackstone and Millville has been raised to high.
In total, there are 32 communities now at critical risk, 39 at high risk, and 121 at moderate risk for the EEE virus in Massachusetts.
There have also been nine confirmed cases of EEE this year in animals; eight horses and one goat.
EEE virus is a rare cause of brain infections (encephalitis). Only a few cases are reported in the United States each year. Most occur in eastern or Gulf Coast states. Approximately 30% of people with EEE die and many survivors have ongoing neurologic problems.
Symptoms & Treatment
Symptoms
The incubation period for Eastern equine encephalitis virus (EEEV) disease (the time from infected mosquito bite to onset of illness) ranges from 4 to 10 days. EEEV infection can result in one of two types of illness, systemic or encephalitic (involving swelling of the brain, referred to below as EEE). The type of illness will depend on the age of the person and other host factors. It is possible that some people who become infected with EEEV may be asymptomatic (will not develop any symptoms).Systemic infection has an abrupt onset and is characterized by chills, fever, malaise, arthralgia, and myalgia. The illness lasts 1 to 2 weeks, and recovery is complete when there is no central nervous system involvement. In infants, the encephalitic form is characterized by abrupt onset; in older children and adults, encephalitis is manifested after a few days of systemic illness. Signs and symptoms in encephalitic patients are fever, headache, irritability, restlessness, drowsiness, anorexia, vomiting, diarrhea, cyanosis, convulsions, and coma.
Approximately a third of all people with EEE die from the disease. Death usually occurs 2 to 10 days after onset of symptoms but can occur much later. Of those who recover, many are left with disabling and progressive mental and physical sequelae, which can range from minimal brain dysfunction to severe intellectual impairment, personality disorders, seizures, paralysis, and cranial nerve dysfunction. Many patients with severe sequelae die within a few years.
Treatment
No human vaccine against EEEV infection or specific antiviral treatment for clinical EEEV infections is available. Patients with suspected EEE should be evaluated by a healthcare provider, appropriate serologic and other diagnostic tests ordered, and supportive treatment provided.Clinical Evaluation (for Health Care Providers)
Cerebrospinal fluid (CSF) findings include neutrophil-predominant pleocytosis and elevated protein levels; glucose levels are normal. Brain lesions are typical of encephalomyelitis and include neuronal destruction and vasculitis, which is perivascular and parenchymous at the cortex, midbrain, and brain stem. There is minimal involvement of the spinal cord.EEEV is difficult to isolate from clinical samples; almost all isolates (and positive PCR results) have come from brain tissue or CSF. Serologic testing remains the primary method for diagnosing EEEV infection. Combined with a consistent clinical presentation in an endemic area, a rapid and accurate diagnosis of acute neuroinvasive EEEV disease can be made by the detection of EEEV-specific IgM antibody in serum or CSF. EEEV IgM tests are available commercially, in some state health department laboratories, and at CDC. A positive EEEV IgM test result should be confirmed by neutralizing antibody testing of acute- and convalescent-phase serum specimens at a state public health laboratory or CDC. To submit specimens for testing at CDC, please contact your state health department.
All EEEV disease cases should be reported to local public health authorities. Reporting can assist local, state and national authorities to recognize outbreaks of this rare disease and to institute control measures to limit future infections.
Eastern equine encephalitis virus (EEEV) is transmitted to humans through the bite of an infected mosquito. 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. All residents of and visitors to areas where EEEV activity has been identified are at risk of infection. People who engage in outdoor work and recreational activities in endemic areas are at increased risk of infection. Persons over age 50 and under age 15 seem to be at greatest risk for developing severe disease when infected with EEEV. Overall, only about 4-5% of human EEEV infections result in EEE. EEEV infection is thought to confer life-long immunity against re-infection. It does not confer significant cross-immunity against other alphaviruses (e.g., western equine encephalitis virus), and it confers no cross-immunity against flaviviruses (e.g., West Nile virus) or bunyaviruses (e.g., La Crosse virus).
In the United States, an average of 7 human cases of EEE are reported annually. To ensure standardization of reporting across the country, CDC recommends that the national surveillance case definition be consistently applied by all state health departments.
Most cases of EEE have been reported from Florida, Massachusetts, New York, and North Carolina. EEEV transmission is most common in and around freshwater hardwood swamps in the Atlantic and Gulf Coast states and the Great Lakes region.
CDC
Massachusetts Department of Health
No comments:
Post a Comment