Last updated: 28 September 2026
For an adopted cat, the most important screening is the FIV/FeLV test, done before it meets your other cats; if it has diarrhoea, add panleukopenia (FPV) and Giardia. At first, keep it in a separate room with its own bowls and litter tray, take it to the vet, and if the FIV/FeLV result is negative, repeat the test after 60 days.
This way you not only give your new cat a good start, but also protect the cats already living with you.
What screening does an adopted cat need?
Every new cat needs an FIV/FeLV test; other tests depend on symptoms and the cat's background.
| Screening | When? | Sample | Why is it important? |
|---|---|---|---|
| FIV/FeLV | On arrival, then again after 60 days | Blood, serum or plasma | An infected cat can be symptom-free for years while passing the virus on. |
| FPV (panleukopenia) | With vomiting, diarrhoea or lethargy, especially in kittens | Faeces | Life-threatening and highly contagious; the virus survives in the environment for months. |
| Giardia | With recurring or prolonged diarrhoea | Faeces | According to ABCD, as many as 30–40% of cats in shelters and catteries may be infected. |
| Coronavirus shedding (FIPV Ag) | In multi-cat households or catteries, if you want to know | Faeces | Shows whether the cat is shedding coronavirus; it does not detect FIP. |
| Intestinal worms, fleas, ear mites | At the first vet visit | Veterinary examination | Deworming and parasite treatment before it meets the others. |
Why must the FIV/FeLV test be done before meeting the other cats?
Because an infected cat can look completely healthy, and FeLV spreads easily to other cats through mutual grooming and shared bowls. According to the AAFP's 2020 guidelines, every cat should be tested as soon as it moves into a new home.
- In a study covering 30 European countries, 5.9% of cats in Hungary were shedding FeLV, one of the highest rates (Studer et al., 2019).
- A recent infection cannot yet be detected: according to the AAFP, FeLV antigen usually appears within 30 days and FIV antibodies within 60 days. That is why a negative test must be repeated after 60 days.
- In kittens under 6 months, antibodies from the mother can cause a false positive FIV result, so a positive result must be rechecked after 6 months of age.
More about the two viruses: FIV and FeLV: why every cat owner should test
How do separation and settling in work?
At first the new cat should live in a separate room with its own bowls, litter tray, bed and scratching post, at least until it has been examined by a vet and you have a negative FIV/FeLV result.
- According to International Cat Care, settling in a separate room can take from a few days to one or two weeks, and introducing the cats should be gradual: first by swapping scents, then with short, supervised meetings.
- Wash your hands after handling the new cat, and only then go to the others.
- International Cat Care recommends that every cat has its own bowl, bed, litter tray and scratching post, plus one spare, spread around the home.
- If the cat has diarrhoea, is vomiting, sneezing or lethargic, extend the separation and talk to your vet.
Which vaccinations does a new cat need?
Every cat should receive core vaccinations against panleukopenia, herpesvirus and calicivirus; FeLV vaccination depends on the cat's lifestyle.
- Kitten: according to ABCD, three doses: at 8–9 weeks, then every 3–4 weeks, with the last at 16 weeks of age or older. According to ABCD the first booster is due at 10–16 months of age; according to the WSAVA 2024 guidelines, from 26 weeks of age.
- Adult cat with unknown vaccination status: your vet will put together the primary vaccination course.
- FeLV vaccination: recommended for outdoor cats or cats living with an FeLV-positive cat, but only after a negative test.
- Rabies: whether it is compulsory for cats depends on the country (in Hungary, for example, it is generally not), but it is required for travel abroad.
According to ABCD, a faecal antigen test can be positive for at least 4 weeks after a live panleukopenia vaccine, so after a recent vaccination have your vet interpret the FPV test.
What should you do if the new cat tests positive?
| Positive result | What to do |
|---|---|
| FIV | Confirmatory test at the vet. According to the AAFP, the risk of infection for other cats in a stable group that does not fight is negligible. |
| FeLV | Confirmatory test, and keep it apart from negative cats, with its own bowls and litter tray. Talk to your vet about vaccinating the others against FeLV. |
| FPV (panleukopenia) | See a vet immediately. The virus is very hardy, so the cat's room must be disinfected with a product effective against parvovirus. |
| Giardia | Veterinary treatment, daily litter tray cleaning, disinfection. According to ABCD, quaternary ammonium compounds are effective against the cysts. Details: Giardia in cats. |
A positive FIV or FeLV result does not mean the cat does not deserve a chance: with the right care and regular vet check-ups it can live well for a long time.
When and where should you ask for screening?
Ideally, the shelter or rescue organisation does the FIV/FeLV test before handing the cat over. Ask when it was done and with which test. If there is no recent result, have it done by a vet after you collect the cat, before it meets the others, or test at home with a combined rapid test. All cat tests: rapid tests for cats.
Frequently asked questions about adopting a cat
Is an FIV/FeLV test needed if the shelter has already tested the cat?
Ask for the test date. If in the 60 days before the test the cat lived with infected cats or cats of unknown status, a recent infection would not yet have shown up, so according to the AAFP the test must be repeated after at least 60 days.
How long should I keep the new cat separate?
At least until a vet has examined it and you have a negative FIV/FeLV result. According to International Cat Care, settling in a separate room takes from a few days to one or two weeks; a cat with symptoms needs longer separation.
My kitten's FIV test was positive. Is it definitely infected?
Not necessarily. Up to 6 months of age, antibodies from the mother can also give a positive result. If the kitten is still FIV-positive after 6 months of age, it is probably truly infected.
Can the FPV test be positive after vaccination?
Yes. According to ABCD, a faecal antigen test can be positive for at least 4 weeks after a live panleukopenia vaccine. After a recent vaccination, have your vet interpret the result.
How many litter trays do several cats need?
International Cat Care recommends one per cat, plus one spare, placed in different parts of the home.
Summary
At first, an adopted cat should live in a separate room until a vet has examined it and you have a negative FIV/FeLV test. If it has diarrhoea, screen for panleukopenia and Giardia too, and repeat a negative FIV/FeLV test after 60 days. This keeps both the new cat and the cats already at home safe.
Sources
- Little S, et al.: 2020 AAFP Feline Retrovirus Testing and Management Guidelines. Journal of Feline Medicine and Surgery, 2020. journals.sagepub.com
- ABCD – European Advisory Board on Cat Diseases: Guideline for Feline Panleukopenia. abcdcatsvets.org
- ABCD – European Advisory Board on Cat Diseases: Guideline for Giardiasis. abcdcatsvets.org
- Studer N, et al.: Pan-European Study on the Prevalence of the Feline Leukaemia Virus Infection. Viruses, 2019;11(11):993. mdpi.com
- International Cat Care: Introducing cats. icatcare.org
- WSAVA: 2024 Guidelines for the Vaccination of Dogs and Cats. wsava.org
Important: this article provides general information and does not replace veterinary advice. The vaccination plan, confirmatory tests and treatment must always be decided by a vet. MancsLab rapid tests are intended for preliminary screening at home.