Post on 07-Feb-2016
description
Division of Public Health Services
New Hampshire Department of Health and Human Services
Eastern Equine Encephalitis (EEE)
in New Hampshire
Dianne Donovan, BSc
Arboviral Surveillance Coordinator
Ddonovan@dhhs.state.nh.us
(603) 271-5927
Division of Public Health Services
New Hampshire Department of Health and Human Services
EEE Transmission Cycle
Mosquito vector
Bird reservoir hosts
Division of Public Health Services
New Hampshire Department of Health and Human Services
EEE History
• 1831 – Horses in MA afflicted with an unknown encephalitis virus
• 1933-1935 – Multiple equine outbreaks along the eastern seaboard
• 1938 – 1st human case in NE reported. MA: 34 human cases, 248 equine
• 1955-1959 – MA reported 16 human cases; NJ reported 33 human cases
Division of Public Health Services
New Hampshire Department of Health and Human Services
EEE Human Cases, MASS, 1974-2006
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YEAR
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f C
ases
Division of Public Health Services
New Hampshire Department of Health and Human Services
EEE
Division of Public Health Services
New Hampshire Department of Health and Human Services
NH Historical Perspective (EEE)• 1973 – 75 equine deaths; 12,000
pheasant deaths
• 1978 – 28 equine deaths
• 1980 – 1 human case reported (not confirmed), 1 equine death
• 1982 – 1 equine death
Division of Public Health Services
New Hampshire Department of Health and Human Services
NH Historical Perspective (EEE)
• 2004: EEE detected in horses, birds, and mosquitoes
• 2005: Human cases
- 7 reported human cases (2 died)
- EEE detected in numerous non-human mammals, birds, and mosquitoes
Division of Public Health Services
New Hampshire Department of Health and Human Services
NH Historical Perspective (EEE)
• 2006: EEE detected in horse, birds, and mosquitoes
• 2007: 3 reported human cases
- EEE detected in mosquitoes, a horse, an alpaca
Division of Public Health Services
New Hampshire Department of Health and Human Services
Division of Public Health Services
New Hampshire Department of Health and Human Services
EEE Symptoms &Clinical Features
Division of Public Health Services
New Hampshire Department of Health and Human Services
EEE - Symptoms• Incubation 4-10 days
• No symptoms in some people infected
• Severe symptoms in others
- short prodrome, ~5 days (fever, headache, abdominal distress)
– Progresses to disorientation, seizures, muscle weakness, paralysis, coma, death
Division of Public Health Services
New Hampshire Department of Health and Human Services
EEE - Clinical Features
• Common: F (83%), HA (75%), N/V (61%)
< 50%: confusion, myalgia, abd pain
< 10%: sore throat, diarrhea, CN palsies
• Imaging (CT, MRI) abnormal in two-thirds of patients
Source: Deresiewicz NEJM 1997
Division of Public Health Services
New Hampshire Department of Health and Human Services
Laboratory Findings(severe neurological disease)
Peripheral Blood
• Normal or elevated total leukocyte count
• Lymphocytopenia
• Anemia
• Hyponatremia
Division of Public Health Services
New Hampshire Department of Health and Human Services
Laboratory Findings(severe neurological disease)
Cerebrospinal Fluid
• Pleocytosis (usually with a predominance of lymphoctyes)
• Elevated protein
• Normal glucose levels
Division of Public Health Services
New Hampshire Department of Health and Human Services
EEE - Diagnosis and Prognosis
• Diagnosis by IgM serum/CSF– Confirmation by PRNT
• Mortality rate 35%
• Neurological sequelae in 30% of survivors
• Lifetime expenses = $3 million/case
Division of Public Health Services
New Hampshire Department of Health and Human Services
EEE Treatment
• There is NO specific treatment.
• Care of patients centers around supportive treatment of symptoms and complications.
• Vaccine – only available for horses.
Division of Public Health Services
New Hampshire Department of Health and Human Services
NH EEE PATIENTS
Demographic & Clinical Characteristics
Division of Public Health Services
New Hampshire Department of Health and Human Services
Demographic & Clinical Characteristics
Age: Mean = 40 years
Range = 4-80 years
Gender: 8 males; 2 females
Onset Date: Earliest = August 3
Latest = October 1
Division of Public Health Services
New Hampshire Department of Health and Human Services
Demographic & Clinical Characteristics
Prodromal Signs & Symptoms:
Fever 9/10
Weakness 9/10
Fatigue 9/10
Headache 8/10
Myalgias 7/10
N/V 7/10
Division of Public Health Services
New Hampshire Department of Health and Human Services
Demographic & Clinical Characteristics
Prodrome Duration (Days):
Mean – 7 days
Range - <1 to ~15 days
SEIZURES: 4/10
COMA: 5/10 DEATHS: 2/10
Division of Public Health Services
New Hampshire Department of Health and Human Services
Suspect Case Reporting
Division of Public Health Services
New Hampshire Department of Health and Human Services
Criteria for Report (a, b, or c)
a. Any patient with viral encephalitis with
- Fever > 100 F
- CNS involvement
- Abnormal CSF profile suggesting a
viral etiology
b. Any patient with presumptive aseptic
meningitis
c. Guillain-Barre syndrome
Division of Public Health Services
New Hampshire Department of Health and Human Services
Criteria for Report
• Severe arboviral disease has occurred in patients of all ages.
• Consider patient travel history in off-season months. Year-round transmission is possible in some areas of the country.
Division of Public Health Services
New Hampshire Department of Health and Human Services
Division of Public Health Services
New Hampshire Department of Health and Human Services
PREVENTION
Division of Public Health Services
New Hampshire Department of Health and Human Services
Personal Protection Works
• Wear long sleeves and pants in light colors to minimize the opportunities for mosquitoes to bite.
• Limit outside activity between evening and dawn when mosquitoes are most likely to bite.
• Consider using an effective insect repellent.
Division of Public Health Services
New Hampshire Department of Health and Human Services
Division of Public Health Services
New Hampshire Department of Health and Human Services
Insect Repellents
Division of Public Health Services
New Hampshire Department of Health and Human Services
Mosquito Repellents: CDC Recommendations
• DEET - Used for >50 years, with millions of
doses applied - Long-term safety established - In children: American Academy of
Pediatrics affirms use of DEET (up to 30%) over 2 months of age
Division of Public Health Services
New Hampshire Department of Health and Human Services
Mosquito Repellents: CDC Recommendations
• Picaridin - Used for years in Australia and Europe - Concentration available in US less - No serious toxicity reported
• Oil of Lemon Eucalyptus - plant derived compound - No serious toxicity reported - Recommended for children >3 years
Division of Public Health Services
New Hampshire Department of Health and Human Services
The Bottom Line
• Repellent adverse reactions, when used appropriately are extremely rare
• EEE (and other mosquito-borne diseases) are definite, recognized threats to human health
- Certain situations (risk factors for severe disease, outbreak situations) increase risk
- Problems following arboviral neuroinvasive disease can be permanent
Division of Public Health Services
New Hampshire Department of Health and Human Services
Repellent Resources
U.S. Environmental Protection Agency
http://www.epa.gov/pesticides/health/mosquitoes/insectrp.
htm
National Pesticide Information Center
http://npic.orst.edu/wnv/
Division of Public Health Services
New Hampshire Department of Health and Human Services
The 2008 Season?
Division of Public Health Services
New Hampshire Department of Health and Human Services
2008 Season?
• Unable to forecast the exact level of risk
• NH communities with prior year’s EEE activity should consider mosquito-borne illness to be a human health risk for 2008
Division of Public Health Services
New Hampshire Department of Health and Human Services
Division of Public Health Services
New Hampshire Department of Health and Human Services
Questions?