Vaccine Titer Reference for Dogs and Cats
Protective antibody titer thresholds for dog and cat core vaccines, and when to use titer testing instead of re-vaccinating.
Dog - protective titer thresholds
| Disease | Protective titer | Notes |
|---|---|---|
| CDV (canine distemper) | ≥ 1:32 (SN) | WSAVA recommends titer over routine re-vaccination after first adult booster. |
| CAV-2 (adenovirus) | ≥ 1:16 (SN) | Cross-protects against CAV-1 (infectious hepatitis). |
| CPV-2 (parvovirus) | ≥ 1:80 (HI) | Long-lasting; titer-based re-vaccination decisions appropriate. |
Cat - protective titer thresholds
| Disease | Protective titer | Notes |
|---|---|---|
| FPV (panleukopenia) | ≥ 1:40 (SN) | Long-lasting protection; titer testing useful. |
| FHV-1 (rhinotracheitis) | ≥ 1:32 (SN) | Titer correlates poorly with disease protection; mucosal immunity matters. |
| FCV (calicivirus) | ≥ 1:32 (SN) | Same caveat as FHV-1 - clinical correlation imperfect. |
When titers are appropriate
| Scenario | Use titer? |
|---|---|
| Adult dog 3 yrs post booster, owner declining re-vaccination | Yes - CDV/CAV-2/CPV titer |
| Newly acquired adult, unknown history | Yes - decide whether to vaccinate |
| Immunocompromised patient (chemo, immunosuppressants) | Yes - assess current protection without challenging immune system |
| Puppy series completion | Less helpful - vaccinate per schedule regardless |
| Rabies | NO - rabies vaccination requirements are legal, not immunological |
Titers measure circulating antibodies and correlate well with protection for some core diseases (CDV, CPV, FPV) but not all. They do NOT replace legally required rabies vaccination.
Frequently asked questions
Can a titer replace the rabies vaccine?
No - rabies vaccination is a legal requirement, not a clinical decision based on antibody status. Titers may be acceptable for international travel in some jurisdictions but rabies vaccine cadence is dictated by local law.
Which diseases have titers that correlate with protection?
Reliable correlation: CDV, CAV-2 and CPV in dogs; FPV in cats. Less reliable: FHV-1 and FCV in cats (mucosal immunity matters more than circulating antibody). Leptospirosis titers don't correlate well with protection - re-vaccinate annually regardless.
How often should I titer a healthy adult dog?
WSAVA suggests every 3 years after the adult booster, in line with the standard re-vaccination interval. If titer is protective, defer re-vaccination; if not, vaccinate.