Disease Outbreak in Livestock

What counts as a possible outbreak?

Several animals showing the same signs, a sudden death with no clear cause, or a sick animal that gets worse quickly can all point to something spreading. So can unusual signs in animals that were healthy yesterday.

You do not need to be sure it is contagious before you act. Treating the situation as possibly spreading costs little, while waiting can cost a herd or flock.

Pay attention to feed intake, water use, behavior and manure as well as obvious signs. Animals that hang back, stand apart or stop eating are often the earliest clue, and those small changes are worth mentioning to your veterinarian.

What should I do in the first hour?

Separate sick animals from healthy ones where you can, and use separate tools, boots and clothing for each group. Stop moving animals on or off the property. Keep dogs, visitors and neighbors away from the affected animals.

Then call your veterinarian. Describe what you see, how many animals, how fast it is moving and what has changed recently.

Work from healthy animals to sick ones, never the reverse, and do chores for the sick group last. Wash up and change clothes before going near other animals or your family. Keep a clean-boot area at the edge of the isolation pen.

• Separate sick and healthy animals
• Pause all animal movement and visitors
• Use separate boots and tools
• Call your veterinarian right away

What information will the veterinarian want?

Gather notes before you call: number affected, ages, signs, when it began, recent feed or water changes, new animals and any deaths. Keep a thermometer reading only if you know how to take it safely.

A written timeline helps far more than memory under stress. Photos and short videos of the signs are valuable too.

Do not give leftover medication or home remedies on your own. The wrong product, dose or timing can hide signs, harm the animal, or leave residues that matter later. Your veterinarian decides what is appropriate for your species and situation.

Can this make people sick?

Some animal diseases can spread to people. Wash hands thoroughly, wear gloves when handling sick or dead animals, and keep children away from them. Do not eat or drink while working with affected animals.

If anyone in the household feels unwell, call a doctor and mention the animals. Your county health department can also advise.

Pregnant people, young children, older adults and anyone with a weakened immune system need extra caution around sick animals. A doctor or the county health office can give advice that fits your household, so ask rather than guess.

Who needs to be notified?

Certain diseases must be reported to state animal health officials, and the list differs by state and species. Your veterinarian normally knows what applies and can make the report or guide you.

You can also call your state veterinarian's office or state agriculture department. Do not rely on a neighbor or a website to tell you what is reportable.

Keep a phone list near the barn: your veterinarian, a backup veterinarian, the state animal health office, and the county emergency management office. When an animal dies suddenly, a calm call with the list at hand saves time.

What about dead animals and shared equipment?

Handle carcass disposal only after talking to your veterinarian or state agency, as methods and rules vary and some diseases need special care. Do not drag carcasses across areas where healthy animals live.

Clean and disinfect equipment, trailers and footwear according to your veterinarian's advice, since the right products depend on the disease.

Ask about testing. Samples sent to a diagnostic laboratory through your veterinarian can identify the cause, which shapes treatment and protects the rest of the herd. Do not move a carcass to a laboratory yourself without instructions.

How do I prepare for next time?

Know your veterinarian's after-hours process before you need it. Keep records of animal ages, vaccinations and movements. Set aside a space that can serve as an isolation pen.

Think about quarantine for new animals before they join the group. Penn State Extension and other state extension programs publish plain guidance on planning ahead.

Insurance and records matter after an outbreak as well. Photographs, dates and veterinary notes may be needed for claims or assistance programs. Ask the Farm Service Agency or your insurer what documentation they would want.

Last reviewed: November 12, 2026. Written by the Rural Farm Life Editorial Team. See our editorial policy.