EP Equine Piroplasmosis Panel, cELISA
Panel of 2 tests that looks in your horse's blood for the defences (antibodies) it made against the two tick...
€74.00 شامل ضريبة القيمة المضافة
About
Equine piroplasmosis is a blood infection of horses, donkeys and mules caused by two tiny parasites, Theileria equi and Babesia caballi. It is spread mainly by ticks.
Many infected horses look perfectly healthy, yet carry the parasite for years and can still pass it on.
This blood test detects IgG antibodies – the antibodies your horse produces against each parasite some time after infection. A positive result means your horse has been infected at some point and may still be a carrier.
Results given as a percentage. For each parasite we report the exact % inhibition measured in your horse's sample, together with the cut-off: below 40% = negative · 40% or more = positive. You see the number, not just a word.
Important: the test detects only IgG. In an acute (recent) infection, IgG antibodies normally appear only about 21 days after infection, so a negative result does not rule out a recent infection.
It is the test most countries ask for before a horse travels, is exported or enters an international competition.
Why test?
- Buying or selling a horse – know its status before the deal.
- Travel, export or international competition – many countries restrict horses with antibodies.
- A horse that is unwell – unexplained fever, anaemia, weight loss or poor performance.
- Routine screening – stud farms, yards and breeding programmes, especially where ticks are common. In a study of 101 healthy horses in Lisbon, about 1 in 3 (32.7%) carried Theileria equi.
Clinical signs
Many infected horses show no signs at all.
When a horse becomes ill, signs usually appear 1 to 4 weeks after infection:
- high fever (often above 40 °C)
- dullness and poor appetite
- pale or yellowish gums
- dark urine
- weight loss and poor performance
- in some cases swollen legs, mild colic or abortion
Transmission
- Ticks – the main route.
- Blood – shared needles, syringes, instruments or blood transfusions.
- Mare to foal – during pregnancy.
A horse that carries the parasite can be a source of infection even when it looks healthy. Horses infected with Theileria equi usually remain carriers for life; Babesia caballi can be cleared over a few years.
Prevention
- Control ticks on horses and pastures.
- Use a new needle and syringe for every horse.
- Test new horses before they join the yard, and before breeding.
- Test before travel, sale or export.
- There is no vaccine.
Results
How to read your report
Your certified report gives two separate results: one for Babesia caballi and one for Theileria equi. For each parasite you will see:
- the % inhibition measured in your horse's sample;
- the result: NEGATIVE or POSITIVE;
- the cut-off: below 40% = negative · 40% or more = positive.
What is % inhibition? The test measures how strongly the IgG antibodies in your horse's blood block a reference reaction. The more antibodies, the higher the percentage. The 40% cut-off is set by the kit manufacturer and is the same for both parasites. There is no "borderline" category: every result is either negative or positive.
Illustrative example: 12% → NEGATIVE · 65% → POSITIVE.
Negative (below 40%)
- No IgG antibodies detected: no evidence that your horse has been exposed.
- Favourable for travel and export.
- A negative result does not exclude a recent infection. The test detects only IgG, and in an acute infection IgG antibodies normally appear only about 21 days after infection. If your horse may have been exposed in the last 3 weeks, or shows signs such as fever, test again after 21 days or ask for our qPCR test, which detects the parasite itself.
- When both parasites are negative, the report states "Piroplasmosis free".
Positive (40% or more)
- IgG antibodies detected: your horse has been exposed and may be a carrier, even if it looks healthy.
- This test cannot tell a current infection from a past one.
- A positive result can restrict travel or export to some countries.
- Next step: talk to your veterinarian. Our qPCR test shows whether the parasite is in the blood now.
Who signs your report
Every report is validated by our Technical Director (DVM, PhD) and issued by Equigerminal, DGAV Official Laboratory No. 22.
Sample
5 mL of blood in a plain (dry) tube for serum, or in a K3 EDTA tube for plasma.
The sample must be collected by a veterinarian.
Send your sample by regular mail or express delivery to:
Equigerminal Lab HIESE
Rua da Quinta do Sobreiro Nº25
3230-343 Penela, Portugal
Turnaround
Same-day results on Wednesdays and Fridays.
We test every Wednesday and Friday. If your sample reaches the laboratory by 12:00 noon on either day, you receive the certified report by e-mail at the end of that day.
Samples arriving after 12:00, or on other days, are tested on the next testing day.
When to ship: send so the sample arrives on a Wednesday or Friday morning. Avoid shipments that sit in transit over the weekend.
Travelling or exporting on a fixed date? Contact us before sampling: +351 938 322 893.
How it works
🛒 Buy the test online.
📧 Receive instructions by e-mail after payment.
🩺 Your veterinarian collects the sample (see Sample).
📄 Complete the submission form with the horse's identification.
📮 Send it to: Equigerminal, S.A., HIESE, Rua da Quinta do Sobreiro, 25, Quinta Vale do Espinhal, 3230-343 Penela, PORTUGAL – to arrive on a Wednesday or Friday morning.
📄 Receive your certified report by e-mail at the end of the testing day.
FAQs
What does my result look like?
For each parasite you get the % inhibition measured in your horse's sample and the interpretation against the 40% cut-off: below 40% = negative, 40% or more = positive. For example: 12% → NEGATIVE · 65% → POSITIVE.
Is this the test required for travel or export?
Yes. cELISA is one of the tests the World Organisation for Animal Health (WOAH) considers most suitable for certifying horses before movement, including international trade. Requirements differ between countries, so confirm with your veterinarian or the official veterinary services before sampling.
My horse is healthy. Can it test positive?
Yes. Many horses carry the parasite without any signs. That is why testing before sale, travel or breeding matters.
cELISA or qPCR – which do I need?
cELISA detects IgG antibodies: it shows whether your horse has been infected and is the test used for movement. qPCR detects the parasite's DNA in the blood. It can be positive at any stage of infection, but the result depends on how many parasites are circulating in the blood sample at the moment it is collected. Our cELISA + qPCR bundle gives both.
When will I get the result?
The same day, if the sample reaches us by 12:00 noon on a Wednesday or Friday.
Can a positive horse be treated?
Your veterinarian can treat it. Babesia caballi can be eliminated; Theileria equi is much harder to clear. Antibodies can stay positive for months after successful treatment.
More
DGAV Official Laboratory No. 22 – recognised by the Portuguese veterinary authority (DGAV) for Babesia caballi and Theileria equi cELISA and for the Coggins test.
Accredited by IPAC under ISO/IEC 17025 (accreditation L0687).
We use USDA-licensed cELISA kits.
For Professionals
1. Assay
- Competitive ELISA (cELISA) with monoclonal antibody, USDA-licensed commercial kit; separate assays for T. equi and B. caballi. Serum or plasma.
- Result reported as % inhibition: ≥ 40% = positive; < 40% = negative.
2. Role in diagnosis and trade (WOAH Terrestrial Manual, ch. 3.6.8, 2021)
- IFAT and C-ELISA have replaced CFT as the tests most suitable for certifying individual animals prior to movement, including international trade.
- C-ELISA ratings (Table 1): +++ population freedom from infection, eradication policies and prevalence surveillance; ++ individual animal freedom prior to movement (recommended, with limitations); not appropriate for confirmation of clinical cases – use PCR (+++).
- Apparent specificity of the T. equi and B. caballi C-ELISAs: 99.2–99.5%.
- In early infection horses may be seronegative while already PCR-positive; antiparasitic treatment may mask infection and cause false negatives.
3. Window period
- The assay detects IgG. In acute infection, IgG antibodies normally become detectable about 3 weeks (21 days) after infection.
- A negative result therefore does not exclude a recent infection. For suspected exposure within the previous 3 weeks, or a febrile horse, use qPCR and/or repeat serology after 21 days.
4. cELISA vs IFAT
- T. equi: good agreement (κ = 0.68, n = 108; Montes Cortés et al., 2017); 34 vs 35 positives in 105 horses (Jaffer et al., 2010).
- B. caballi: weaker agreement (κ = 0.22; Montes Cortés et al., 2017); cELISA detected 16 vs 11 IFAT positives (Jaffer et al., 2010).
5. Serology vs PCR – interpretation
- cELISA + / qPCR + – active infection or carrier with detectable parasitaemia.
- cELISA + / qPCR − – carrier with parasitaemia below the detection limit, or treated horse.
- cELISA − / qPCR + – recent infection before seroconversion; repeat serology after 21 days.
- cELISA − / qPCR − – no evidence of infection.
In 105 horses: 30 positive by both, 8 serology-only, 3 PCR-only (Jaffer et al., 2010).
6. Carriers and treatment
- T. equi: lifelong carrier state is usual; B. caballi may be cleared within a few years (Onyiche et al., 2019).
- Imidocarb dipropionate 4 mg/kg IM, 4 doses at 72 h, eliminated B. caballi: qPCR negative within 5 days; cELISA seroreversion at 201 days (Schwint et al., 2009). Treatment failures are reported (Mendoza et al., 2024).
7. Genetic diversity of T. equi
- Five 18S rRNA lineages (A–E); lineage C corresponds to Theileria haneyi. Lineage E is not detected by ema-1/ema-11-based assays (Mège et al., 2026; Bishop et al., 2020). Where a non-A lineage is suspected, combine serology with 18S-based qPCR.
8. Epidemiology – Iberian Peninsula
- Portugal: T. equi in 32.7% of 101 healthy horses in Lisbon; B. caballi not detected (Fuehrer et al., 2020).
- Spain (central and south-west): 52% seropositive by IFAT in 3,100 healthy horses – 44% T. equi, 21% B. caballi (Montes Cortés et al., 2017).
References
- WOAH Terrestrial Manual, ch. 3.6.8 Equine piroplasmosis (updates adopted 2021).
- Bishop RP et al. (2020) Parasit Vectors 13:261.
- Fuehrer HP et al. (2020) Front Vet Sci 7:591943.
- Jaffer O et al. (2010) Parasitol Res 106:709–713. doi:10.1007/s00436-009-1669-5
- Mège M et al. (2026) Ticks Tick Borne Dis 17:102656.
- Mendoza FJ et al. (2024) Front Vet Sci 11:1459989.
- Montes Cortés MG et al. (2017) Parasite 24:14.
- Onyiche TE et al. (2019) Int J Environ Res Public Health 16:1736.
- Schwint ON et al. (2009) Antimicrob Agents Chemother 53:4327. doi:10.1128/AAC.00404-09