Approximately 70 La Crosse Encephalitis cases reported per year .

Causes

Virus cycles in woodland habitats between the treehole mosquito (Aedes triseriatus) and vertebrate hosts (chipmunks, squirrels). Virus survives winter in mosquito. Vector uses artificial containers (tires, buckets, etc.) in addition to treeholes. La Crosse virus is a California serogroup virus in the family Bunyaviridae

Risk Factors

• Children <16 years old: biological risk factor

• Residence in woodland habitats environmental risk factor

• Containers at residence environmental risk factor

• Outdoor activities: behavioral risk factor

• Rural poor most affected

Symptoms

Frank encephalitis progressing to seizures, coma; majority of infections are subclinical or result in mild illness

Diagnosis

Performed by doctor and laboratory tests.

Prevention

Use mosquito repellant when outdoors, there is no vaccine available.

References

CDC