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When to Quarantine Cats Exposed to Feline Panleukopenia


Authors: Dr. Alexandre Ellis
Document Type: FAQs
Topics: Infectious Disease
Species: Feline

When feline panleukopenia (FPV) strikes, how long should we quarantine cats that have been potentially exposed? Dr. Ellis details the steps for risk assessment.


Help! We have a litter of kittens who broke with panleukopenia in one of our wards. One of the kittens suddenly passed away and tested positive for panleukopenia on a SNAP test. We immediately isolated the litter of kittens in a separate room.  I am wondering how long I should keep the other cats from that ward under observation and quarantined from the adoptable population. There are kittens and adult cats. They are all currently doing well and do not have any signs of disease.

Thank you very much!


Thank you for reaching out for advice on this situation. This virus can certainly be a scary one to be faced with.  I do have recommendations for your current situation and have provided a resource which will help you to assess the risk for infection to other cats. 

Transmission of feline panleukopenia virus occurs by exposure of a susceptible cat to fecal material from an infected cat. The incubation period, meaning the time it takes from exposure for a cat to show clinical signs, can be up to 14 days; however, it is typically closer to 3-7 days. Cats can shed the virus for 2-3 days prior to showing clinical signs.  Lethargy, fever and gastro-intestinal signs such as vomiting, diarrhea, and decreased appetite are commonly seen with panleukopenia. It should also be the top suspicion when sudden death is seen in a cat of any age. Your practices of prompt recognition of illness, diagnostic testing, separation and response are all important to reduce the spread within the shelter.  

If no other cats appear ill, the next step is risk assessment in an effort to categorize individuals as more or less at risk for developing infection. Groups at potentially increased risk include kittens under 5 months of age (regardless of vaccination status), unvaccinated cats, and cats vaccinated less than a week before exposure. Infectious dose plays an important role in risk assessment and cats with close contact (littermates, cage-mates) are considered to be at greater risk. Reduced risk for infectious disease spread is seen when shelters practice FVRCP vaccination immediately upon intake of all cats, double compartment housing is provided for all cats, spot cleaning is implemented, a parvocidal product is used (e.g. Rescue®), gloves are changed between litters/juveniles and there is a protocol in place for monitoring and prompt recognition and response occur when clinical signs of illness are observed. Many shelters find that panleukopenia does not spread beyond the initially affected litter when implementing the above practices and thus do not find the need to quarantine or do further testing of other felines in the same ward.

If significant exposure was likely, cats over 5 months old who were vaccinated less than a week prior to exposure, and kittens can have blood antibody titers measured to further assist with risk assessment. Cats and kittens (without clinical signs) that have high antibody levels are likely protected at that point in time of exposure and are unlikely to become ill. It is important to be aware that antibody levels may wane in kittens under 5 months of age so reducing further exposure is essential. Low antibody levels do not guarantee cats will become infected but they are considered higher risk and quarantine may be best for this group. Titers can be sent to a commercial lab (such as the UW titer lab through UWSMP which offers discounted testing for shelters) or done using an in-house testing kit such as Vaccicheck. Sensitivity and specificity for feline Vaccicheck has not been shown to be quite as good as the canine kit so a commercial lab may be most reliable and cost-effective. Cats over 5 months of age, that were vaccinated a week prior to exposure, are at very low risk for developing panleukopenia and we would advise to continue them on their adoption path without further testing if no signs of illness are present.

When implementing a quarantine for high risk cats/kittens the longest incubation time of 14 days is often utilized. Because most cats will become ill 3-7 days after exposure, some shelters have elected to do a shorter quarantine and adopt cats without signs of illness earlier than 14 days with counseling of adopters. While quarantine may reduce some risk of adopting out a cat incubating panleukopenia virus, it is not without consequence as exposure to other infectious diseases may occur during the quarantine in addition to the challenge of meeting the needs of cats while in a shelter for a prolonged time and avoiding crowding.

More information can be found in our online Panleukopenia Guidebook.

Please let me know if you have any further questions!

University of Wisconsin Shelter Medicine Program

Alex Ellis, DVM
Maddie’s Shelter Medicine Resident (2017-2020)
Shelter Medicine Program
University of Wisconsin – School of Veterinary Medicine