Viral Profiles

LaCrosse virus (genus: bunyavirus. Isolated from a case in LaCrosse, Wisconsin)


incubation is around 7 days. acute illness for 10 days (first 1-3 days marked by nonspecific symptoms including fever, headache, nausea, vomiting and lethargy; afterwards, stiff neck, lethargy, seizures).
Severe disease often occurs in children under 16 years (seizures, coma, paralysis, and neurological sequela).


few people die during the acute phase
10% of children develop epilepsy as a sequela
learning disabilities and other objective cognitive deficits reported in 2% of patients


geographic distribution: concentrated in the midwestern United States; Present throughout the United States east of the Mississippi River
vector: Aedes triseriatus mosquito
natural host: woodland rodents
-most cases occur in July, August or September
-people aged 1-14 years are at greatest risk for exposure to the vector (due to hiking and camping activities)
0.3% fatality rate


Prevention and Management educate the public about spread and control; destroy larvae and eliminate breeding sites of vectors (by destroying and spraying tires with insecticide in particular); mosquito nets and screens; use of mosquito repellant

Bwamba (bunyavirus. Bwamba group)

symptomology febrile illnesses lasting a week or less. Initial symptoms: fever, headache, malaise, arthralgia, myalgia, rash
outcome inapparent infection and mild disease are common

only identified in Africa
vector: mosquito

prevention and control mosquito-control; repellant; educate public about spread and control

Bhanja (genus: unclassified)


incubation: usually 4-5 days

outcome can cause severe neurologic disease and death; second attacks are rare

vector: tick
found in Africa, Europe, Asia. Susceptibility is apparently universal

prevention and control personal protection against ticks (light-colored clothing, avoid infested areas, tuck pants into socks, repellant, tick control)

Oropouche Virus (genus: bunyavirus. Simbu group)

symptomology acute febrile illness of 1-2 weeks duration. incubation usually 3-12 days. Arthralgia, myalgia, headache, prostration.
outcome no deaths occur. after acute illness, patients recover rapidly. inapparent infection and mild disease are common.

cause of repeated epidemics in Para province of Northern Brazil. Found in Brazil, Trinidad, Panama, and Peru.
vector: midge--Culicoides pararesis
epidemics only occur in rainy season and last no longer than six months
virus possibly maintained in cycle involving sloths, monkeys and jungle mosquitoes

prevention and control same general measures used for mosquito-borne viral encephalitides. mosquito repellant.

For more Bunyavirus profiles, please see another student webpage at:


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