"My cat only stays indoors, the breeder said its kitten vaccines are complete, so it never needs a booster for life, is that true?" Questions like these come into our WhatsApp regularly, usually after a pet owner reads something in a Facebook group, hears it from a neighbour, or is told by someone who "knows better". Some of the information circulating is indeed accurate, but plenty is also outdated, taken out of context, or generalised from a specific case.
This article debunks the 10 most common myths about dog and cat vaccines in Indonesia, referencing the latest WSAVA 2024, AAFP/AAHA, AVMA, and ISFM guidelines. The goal is not "vaccinate everything without thinking", but to help you make decisions based on accurate information rather than myths. Some concerns (e.g. FISS in cats) do have a medical basis, we clarify where the risk is real and where it is exaggerated.
Myth 1: "Indoor cats don't need vaccines"
Fact: Indoor cats have a lower exposure risk, but it is not zero, and some diseases can still enter the home through unexpected routes.
- The panleukopenia virus (FPV/feline distemper) is extremely hardy in the environment, it can be carried in on an owner's shoes, shopping bags, or clothing from outside
- A cat that slips out briefly when a door opens, or fights with a new cat that gets into the home, rabies and respiratory virus contact can happen in a matter of seconds
- Pet hotels, premium grooming salons, or clinics with boarding usually require proof of complete vaccination, if you need to board your cat while travelling, an expired vaccine will be a blocker
- If there will be a second cat in the home in the future, or if you volunteer at a rescue/shelter, viruses can be carried in
The AAFP/ISFM 2020 and WSAVA 2024 guidelines still place FVRCP (Tricat) as a core vaccine for all cats, including indoor ones. Booster frequency can be less frequent for indoor cats (every 3 years for core vaccines after the initial series is complete, vs annual for high-risk factors), but this decision needs to be discussed with a vet, not a "skip entirely".
Myth 2: "Vaccines cause autism or permanent behaviour changes"
Fact: This claim is adapted from a human vaccine myth that the medical community has debunked many times over. There is no peer-reviewed study showing a correlation between vaccines and autism in humans or animals.
- The original study that sparked the human autism-vaccine claim (Wakefield 1998) was formally retracted from The Lancet over methodological fraud, and the author lost his medical licence
- In dogs and cats, "autism" as a veterinary diagnosis does not exist in standard medical terminology, obsessive-compulsive behaviour does exist, but its causes are multifactorial (genetics, environment, stress), not vaccines
- Real post-vaccine reactions do exist (see the article Pet Vaccine Side Effects: Normal vs Concerning), but those are not "permanent personality changes", rather an immune reaction that is usually transient
Myth 3: "Too many vaccines at once will overload the immune system"
Fact: The immune system of dogs and cats is designed to deal with millions of antigens from the environment every day (bacteria on the floor, pollen, dirt, parasites). A vaccine with 3-5 antigens at once is an extremely small load compared to natural exposure.
- WSAVA 2024 states that core vaccine combinations (DHPP/DHPPi for dogs, FVRCP for cats) have been tested for compatibility by manufacturers, with no evidence of "overload" in healthy animals
- Combining rabies with core vaccines in the same visit is commonly done and safe, with injections at 2 separate sites
- For small animals (<5 kg), seniors with a history of vaccine reactions, or immunocompromised animals, some vets space out vaccines by 2-4 weeks for safety, but this is a case-by-case decision, not a general rule
What is real is a vaccine reaction as a rare event (less than 1% of cases), not an "immune overload". Discuss any history of prior reactions with your vet.
Myth 4: "Vaccines cause lifelong allergies"
Fact: Vaccine allergic reactions (type I hypersensitivity) do exist, but are very rare, estimated at less than 0.5% of all vaccinations. These reactions occur within the first minutes to hours after injection, not as a "lifelong allergy that appears years later".
- Signs of acute allergy: facial swelling, severe itching all over the body, repeated vomiting, difficulty breathing, collapse, all require immediate veterinary care
- If an animal has had a vaccine allergic reaction before, the vet usually pre-medicates with an antihistamine (diphenhydramine) before the next vaccine, or splits the vaccines one by one to identify the cause
- Food allergies, pollen allergies, or atopic dermatitis that appear months/years after a vaccine are not caused by the vaccine, their causes are multifactorial (genetics, environment, diet), the timing is merely coincidental
Myth 5: "Purebred cats (Persian, Ragdoll, Maine Coon) are more vulnerable to vaccines"
Fact: There is no scientific evidence that purebred cats are more prone to vaccine reactions than ordinary domestic cats. What is real is that some breeds have a genetic predisposition to certain conditions (Persians are prone to kidney PKD, Maine Coons are prone to cardiomyopathy), but this is independent of vaccine response.
- What is true: cats with autoimmune disease or that are immunocompromised (FeLV+, FIV+, active cancer) need individual evaluation before vaccination, the decision to modify the protocol vs continue standard depends on the condition
- For healthy purebred cats: the vaccine protocol is the same as for domestic cats, FVRCP core + rabies in endemic areas
Myth 6: "Vaccines cause cancer in cats (FISS)"
Fact: This is a myth with an element of truth, the nuance needs clarification.
Feline Injection-Site Sarcoma (FISS) is a rare but serious tumour that appears at a previous injection site several months to years after a vaccine (or any injection, not just vaccines). The risk factor is estimated at 1 per 10,000 to 1 per 30,000 vaccine injections in cats, very low, but the consequences are significant.
- The AAFP and WSAVA FISS Task Force acknowledge this risk and recommend mitigation: use non-adjuvanted vaccines where available, and inject at specific sites (lower limb or distal tail, not the scruff) so that if a tumour appears it is easier to remove with clear margins
- The "3-2-1" rule for post-vaccine monitoring: if there is a lump at the injection site that persists >3 months, is >2 cm in size, or enlarges after 1 month, a biopsy is mandatory
- The FISS risk does not eliminate the recommendation for core vaccines in cats, panleukopenia, calicivirus, and rhinotracheitis remain killers with mortality far higher than FISS. The risk-benefit balance still favours vaccination, but with injection-site mitigation
Discuss injection site and whether a non-adjuvanted vaccine is available with your vet.
Myth 7: "A titer test is enough, no need for vaccine boosters"
Fact: A titer test (measuring antibody levels in the blood) is not a general substitute for vaccination. Titer tests have benefits and limitations that need to be understood.
- Titer tests are useful for: confirming protection in dogs/cats with an unclear vaccine history (rescue/shelter), booster decisions in animals with a history of severe prior vaccine reactions, international travel needs (e.g. the RNATT rabies test for Australia/Japan)
- Titer tests are not useful for: rabies vaccine as a booster substitute (government regulations still require an active vaccine, not a titer), bacterial vaccines (Leptospira, Bordetella), antibodies drop quickly, titer is not predictive
- The cost of a titer test can be higher than the vaccine booster itself, it depends on the type of panel, the availability of an accredited local lab, and whether the sample needs to be sent to an overseas lab. For a cost estimate suited to your pet, contact our WhatsApp for a free consultation and estimate
- WSAVA 2024 endorses the use of titers for specific situations, not routinely as a substitute for core vaccines
Myth 8: "Human vaccines can be used for animals"
Fact: Never. Human vaccines and animal vaccines are different products, the antigen formula, adjuvant, dose, and target species all differ.
- The human rabies vaccine (for post-exposure prophylaxis after a bite) will not produce an adequate protective response in dogs/cats
- Adjuvant components in human vaccines can trigger different reactions in animals
- The DHPP/FVRCP vaccine diluent is designed for multi-antigen combinations, human vaccines do not have an equivalent composition
- Legally: animal vaccination must be carried out by an authorised veterinarian using products registered for that species (in Indonesia: Permentan + WOAH guidelines)
The reverse also applies, animal vaccines must not be used for humans.
Myth 9: "The breeder said the kitten/puppy vaccines are complete, so no booster is needed for life"
Fact: "Complete vaccines from the breeder" only means the initial puppy/kitten vaccine series is finished (typically 3-4 doses between 6-16 weeks of age). For long-lasting immunity, adult animals still need boosters after the initial series.
- WSAVA 2024 recommends: a first booster at 6 months of age (or 12 months after the last puppy/kitten vaccine) to ensure mature immunity after maternal antibody influence has truly disappeared. Many rescues/shelters with high-exposure conditions choose to booster at 6 months
- After that, core vaccine boosters can be every 3 years (dogs DHPP, cats FVRCP), rabies per the product label (1 or 3 years) + local regulations, while non-core vaccines (Lepto, Bordetella, kennel cough) are boostered annually because immunity is shorter
- "Never boostered again since puppy/kitten" = thin immunity in adulthood, especially for diseases whose natural duration of immunity declines after a few years
Myth 10: "Holistic / homeopathic / nosodes can replace vaccines"
Fact: There is no scientific evidence showing that nosodes or homeopathic remedies provide protection against infectious disease in animals.
- A nosode is an ultra-diluted homeopathic product made from disease material, claimed to stimulate immunity, but at typical homeopathic dilutions (10^-30 or more), no active molecule physically remains in the solution
- WSAVA, AVMA, AAHA, AAFP, and the British Veterinary Association explicitly state that nosodes are inadequate as a substitute for conventional vaccines
- Animals "vaccinated" with nosodes that are then exposed to parvovirus, distemper, or panleukopenia can develop severe disease with high mortality, outbreaks at several rescue shelters using nosode-only protocols are documented in the veterinary literature
- Holistic care as a complement (optimal nutrition, stress management, environmental enrichment), that is valid and beneficial. But a complement is different from a substitute
Myth 11 (bonus): "One vaccine in puppy/kitten stage is enough for life"
Fact: A single dose of a combination vaccine in a young animal is not enough, maternal antibodies from the mother can still "block" the vaccine response at certain ages, and immunological memory needs repeated stimulation to mature.
- WSAVA 2024 minimum: 3 doses of core vaccine in the initial series (at 6-8 weeks, 10-12 weeks, 14-16 weeks for DHPP/FVRCP), with the last dose no earlier than 16 weeks of age, the reason: at this age maternal antibodies have dropped enough for a reliable vaccine response
- A booster at 6-12 months of age to ensure mature immunity
- "Just one kitten/puppy vaccine is enough" = suboptimal immunity, the animal remains at risk of core diseases
What is important to remember
Vaccines are not a religion, the decision to vaccinate must be based on accurate information about risk-benefit, the animal's lifestyle, individual health status, and local regulations. Some principles held by the veterinary medical community:
- Core vaccines are essential for all dogs and cats, DHPP for dogs, FVRCP for cats, rabies in endemic areas
- Non-core vaccines based on risk, Leptospira for dogs that often contact water/soil; Bordetella for dogs frequently in kennels/daycare; FeLV for outdoor cats or multi-cat households
- Booster frequency can be individualised, not "annual for everything mandatory", but also not "skip entirely". WSAVA 2024 endorses the approach "vaccinate as much as necessary, but as little as possible"
- Side effect monitoring, discuss any history of prior reactions, the injection site for cats (FISS mitigation), pre-medication if there is an allergy history
- Consult a veterinarian, before deciding to modify a protocol based on information from a group or breeder. Many pet owners doubt vaccines after reading 1 post in a group, when the context of that case does not match their own animal
If you are confused about the vaccine protocol for your pet, or have conflicting information from various sources, a consultation is the right step. We help evaluate vaccine history, health status, lifestyle, and discuss the protocol options that suit your pet, not push "everything mandatory now".
Want to consult about your pet's vaccination at home without carrier stress? See Prabasa Vet's home vaccination service or directly contact our WhatsApp for a free consultation and a discussion of the right protocol.
Read also: Complete Pet Vaccination Guide, Complete Cat Vaccine Schedule, Dog Vaccine Schedule: Puppy + Adult, Rabies Vaccine for Dogs and Cats in Indonesia, Pet Vaccine Side Effects: Normal vs Concerning.
Medical references used in this article
This article was prepared with reference to the following sources, verified per clinical statement:
- Squires RA, et al. WSAVA Guidelines for the Vaccination of Dogs and Cats. Journal of Small Animal Practice 2024 , core vs non-core classification, booster frequency, indoor cat recommendation, the "as much as necessary, as little as possible" principle
- AAFP/AAHA Feline Vaccination Advisory Panel Report 2020 , indoor cat vaccine recommendation, injection site for FISS mitigation, FISS Task Force "3-2-1" monitoring rule
- Plumb's Veterinary Drug Handbook, 7th edition, core and non-core vaccine monographs, contraindications, post-vaccine reactions
- AVMA Position Statement on Homeopathic Treatments, nosodes are inadequate as a substitute for conventional vaccines
- ISFM (International Society of Feline Medicine) consensus position, vaccines for indoor vs outdoor cats, protocol modification for senior or immunocompromised cats
- British Veterinary Association position statement on homeopathic veterinary medicine 2017 , nosode efficacy
This article is general guidance based on the international WSAVA, AAFP/AAHA, AVMA, and ISFM guidelines. For your pet's specific condition, including any history of prior vaccine reactions, current health status, lifestyle, and the endemic zone of your area, consulting a veterinarian is the right step.
