How it spreads
Mosquitoes, flies and ticks carry the virus from a sick animal to a healthy one in a single bite, so animals do not need to touch for it to move through a herd. Shared needles, unclean instruments and common feed and water troughs also pass it between animals.
Which animals are most at risk
Both cattle and buffalo are affected. Young calves, pregnant and lactating cows and breeding bulls generally warrant the closest daily attention, though every animal in an affected area is worth watching.
The signs, and the phase before them
There is a period after infection when the virus is multiplying and the animal still looks well. The earliest signs are easy to miss: an animal goes off feed, or feels warmer than usual for more than a day, before any lump appears. Running a hand over the neck, back and legs can find swelling under the skin earlier than the eye can.
Recovery takes longer than the fever
Once the fever settles the animal is not necessarily back. Milk yield returns gradually and fertility can be affected, so feed, appetite and body condition are worth supporting through the whole recovery rather than only while the animal is visibly ill.
Reducing exposure around the shed
Removing standing water, controlling insects at dawn and dusk when they are most active, and keeping the shed and its surroundings dry and clean all reduce exposure. These measures lower the risk rather than removing it.
