Wednesday, May 15, 2013

Rotavirus in Alpacas

After our debut at an alpaca show in Denver last week, we brought home not only a blue ribbon but Rotavirus.  It had spread throughout the show and many animals began to show symptoms on the last day.  While the event veterinarian confirmed several days after the show that is was Rotavirus, sickness had already begun to spread through our weanling herd.

Our young alpacas showed signs of fever (102 F to 106 F) with diarrhea and lethargy.  We isolated this group from other alpaca herds and gave them antibiotics, anti-inflammatories, Pedialite and Gatorade to help with dehydration.  

Many adults will be exposed to the sickness but already have the antibodies in their systems to fight any infections.  Alpacas under one year of age are at a higher risk without the previous exposure to build up immunities.   It is often not the virus that will kill an alpaca, but the secondary problems caused by the sickness.


With Rotavirus, there are two main concerns - 


1.  Respiratory infection can be lethal and those most vulnerable can die in 48 hours.  Most will receive high temps, snotty nose, diarrhea causing dehydration.  They can show one or all of these signs, or be so stoic they simply tip over and die. 

2.  The virus attaches to the inside layer of bowel wall, causing leakage of diarrhea resulting in bacterial infections and inhibits absorption of nutrients and liquids.  

According to the CDC website:

  • The incubation period for rotavirus disease is approximately 2 days.
  • The disease is characterized by watery diarrhea for 3 to 8 days, and occasionally fever and abdominal pain.
  •  Immunity after infection is incomplete, but repeat infections tend to be less severe than the original infection.
  • Younger animals seem to be more severely affected (because many older animals will have some immunity if previously exposed)
  • The virus is stable in the environment and resistant to various chemical disinfectants and bleach
  • Because the virus is stable in the environment, transmission can occur through ingestion of contaminated water or food and contact with contaminated surfaces or objects
  • Rotavirus gastroenteritis is a self-limited illness, lasting for only a few days. Treatment is nonspecific and consists of oral or IV rehydration therapy to prevent dehydration (especially in young animals) and supportive care such as anti-diarrheal medications and probiotics.
  • Rotaviruses are generally species-specific and the transmission from animals to humans is very rare
  • Even with good biosecurity measures on the farm it is difficult to prevent the infection of na├»ve animals due to the shear number of viral particles shed during clinical disease and the fact that the virus is stable in the environment. 
  • There is no rotavirus vaccine approved for use in camelids and the vaccine for cattle/neonatal calves is not recommended.
Although most animals recover without veterinary intervention some animals may need more aggressive supportive therapy.  Thus, be sure to monitor temperatures and ensure they are getting plenty of liquids.  You may need to give a water bath if their temperatures get too high.  Quarantine the sick animals and talk to your vet about  antibiotics and anti-inflammatories.