Coccidioidomycosis (Valley Fever) in Llamas: Lung Signs, Testing & Prognosis

Coccidioidomycosis, often called Valley fever, is a fungal infection caused by Coccidioides organisms that live in dry, dusty soil. Llamas become infected by breathing in airborne spores, especially in endemic parts of the southwestern United States. The lungs are usually affected first, so many llamas develop a chronic pneumonia pattern with cough, increased breathing effort, and gradual weight loss.

In camelids, this disease can be tricky because signs may start slowly and look like other respiratory problems. Some animals have mainly lung disease, while others develop disseminated infection, meaning the fungus spreads to lymph nodes, bones, skin, or other tissues. A UC Davis review confirmed that llamas and alpacas are susceptible in endemic areas, and llamas were well represented among diagnosed cases.

For pet parents, the key point is that Valley fever is serious but not hopeless. Some llamas respond to long-term antifungal treatment, especially when disease is recognized before severe spread occurs. Because symptoms overlap with bacterial pneumonia, parasitism, weight-loss disorders, and other fungal diseases, your vet usually needs testing rather than symptoms alone to sort it out.

Valley fever is caused by inhaling spores from the soil fungus Coccidioides immitis or Coccidioides posadasii. These fungi are associated with arid and semi-arid environments. In the United States, the highest-risk regions are in the Southwest, especially parts of Arizona, California, Nevada, New Mexico, Texas, Utah, and Washington, although the fungus is not evenly distributed and can occur outside mapped areas.

Spores become airborne when soil is disturbed by wind, digging, construction, vehicle traffic, or dry-season dust. That means llamas do not need direct contact with another sick animal to become infected. The disease is considered environmental, not contagious, so herd spread usually reflects shared exposure rather than llama-to-llama transmission.

Not every exposed llama becomes ill. Some likely clear infection or remain subclinical, while others develop pneumonia or disseminated disease. Case series in camelids suggest that living in endemic areas increases risk, and one UC Davis study found male llamas had increased risk compared with female llamas and male alpacas. Your vet will also consider stress, transport, concurrent illness, and immune status when discussing why one animal became sick while another did not.

Diagnosis usually starts with a careful history and exam. Your vet will want to know whether your llama lives in, or has traveled through, an endemic region and whether signs are mainly respiratory or also involve weight loss, lameness, skin lesions, or neurologic changes. Initial testing often includes a CBC, chemistry panel, fibrinogen or inflammatory markers, and thoracic imaging such as chest radiographs or ultrasound when available.

The most common next step is coccidioidal serology, which looks for antibodies. Serology can be very helpful, but it is not perfect, so results need to be interpreted alongside the exam and imaging findings. Merck notes that diagnosis can be challenging and may rely on serology or direct demonstration of fungal spherules in tissue. In some cases, your vet may recommend a transtracheal wash, lymph node aspirate, biopsy, or cytology if a safer sample site is available.

If disease outside the lungs is suspected, your vet may add limb radiographs, ultrasound of enlarged lymph nodes or masses, and targeted sampling of abnormal tissue. Referral may be worthwhile when a llama is unstable, when imaging is limited in the field, or when the diagnosis remains uncertain after first-line testing. Because treatment is long and monitoring matters, confirming the diagnosis as well as practical circumstances allow is usually worth discussing.

There is no widely available vaccine for Valley fever in llamas, so prevention focuses on lowering exposure to airborne dust in endemic regions. That can include feeding hay in ways that reduce dust clouds, limiting access to heavily disturbed dry lots, wetting down high-traffic areas when practical, and being thoughtful about turnout during major wind events, excavation, or nearby construction.

Prevention is not perfect because Coccidioides lives in the environment and may be present even when a property looks clean. Still, reducing dust burden is a reasonable step, especially for llamas with prior respiratory disease, older animals, or herds living in highly endemic areas. Good nutrition, parasite control, and prompt attention to chronic cough or weight loss may also help your vet catch illness earlier.

If you move llamas into or out of the Southwest, share that travel history with your vet. Valley fever can appear weeks to months after exposure, so a llama that now lives outside an endemic area may still need testing if respiratory signs develop later. Early recognition does not prevent infection, but it can improve decision-making and may support a better outcome.