Veterinary Public Health

Coccidioidomycosis (Valley Fever) in Animals - Case Definition

About This Case Definition

This case definition is used to evaluate and categorize cases of coccidioidomycosis reported in animals to the Los Angeles County Department of Public Health. It was developed by public health veterinarians by reviewing published literature and reported cases of coccidioidomycosis in LA County animals. Earlier case reports of this disease were reviewed and a few reclassified to meet this 2015 case definition.

Learn more about animal disease surveillance in LA County, and about cases of coccidioidomycosis in animals in LA County.

Case Definition - Coccidioidomycosis (Valley Fever) in Animals - 2015

Confirmed

  • Organism identified by biopsy, cytology, positive culture, molecular techniques, or
  • Antibody titer (either IgM or IgG) ≥ 1:16 PLUS compatible clinical findings

Probable

  • Antibody titer (either IgM or IgG) ≥ 1:4 and < 1:16 PLUS compatible clinical findings

Suspected

  • Antibody titer (either IgM or IgG) positive but < 1:4 PLUS compatible clinical findings

Not a case

  • Does not meet the case definition of CONFIRMED, PROBABLE or SUSPECTED, or
  • No compatible clinical findings AND antibody titer < 1:4 (i.e. incidental low positive titer)

Compatible clinical findings

Animal has at least one of the disease syndromes below. Respiratory disease is the most common finding in dogs, while lameness is the second most common. Skin lesions are the most common in cats.

  • Respiratory: Cough AND at least one of the following: fever, anorexia, weight loss, radiological evidence of pulmonary disease or response to systemic antifungal treatment.
  • Bone disease: Lameness with focal or multi-focal bone pain AND at least one of the following: fever, anorexia, weight loss, radiological evidence of bone disease or response to systemic antifungal treatment.
  • Cutaneous disease: Draining, ulcerating or mass-like skin lesions that is either non-responsive to antibacterial therapy AND/OR responsive to antifungal therapy.
  • Disseminated disease: 3 of the following findings must be present: fever, anorexia, weight loss, enlarged lymph node(s), weakness, seizures, ataxia, keratitis, uveitis, acute blindness, vomiting, diarrhea, heart failure or response to systemic antifungal treatment.

Exposure location

In general, cases are considered to be "Other" or "Unknown" unless the history indicates no travel outside of area.

  • UNKNOWN - Less than 2 months of travel history available.
  • LA COUNTY - No travel outside of LA County in the 2 months before first onset of disease
  • SO CAL - No travel outside of southern California in the 2 months before first onset of disease
  • OTHER - Dog traveled or lived outside of southern California into other areas that are endemic for Coccidioidomycosis in the two months before first onset of disease.

For the purpose of this case definition Southern California includes the following counties: Los Angeles, Orange, San Luis Obispo, Kern, Santa Barbara, Ventura, San Bernardino, Riverside, San Diego & Imperial.

Rationale for surveillance in animals

Animals cases are sentinels for the risk of mosquito borne disease in general. Animals are sentinels. Cases indicate that fungus is in soil in animal's environment. Humans in same environment may also be exposed. Epidemiological data is valuable to LA County veterinarians.

References