Several diseases and water-quality problems can look alike. Sudden deaths, falling feed intake or breathing distress need prompt advice from a qualified aquatic animal health professional and an appropriate diagnostic laboratory.
What it is
EHP is a fungal-related microsporidian parasite that multiplies inside host cells. It is widely called Enterocytozoon hepatopenaei; a 2023 taxonomic redescription proposed the name Ecytonucleospora hepatopenaei. Both names occur in technical references, and the abbreviation remains EHP.
Infection can be inconspicuous. Poor growth deserves investigation even without white faeces; sudden deaths require a wider investigation for additional causes.
Signs to watch for
- Average weight falls behind the crop’s previous growth trend.
- The sampled population develops a widening range of sizes.
- Feed conversion worsens; these observations are warning signs, not confirmation.
What else can look similar?
- Unequal feed access, crowding, or unsuitable water conditions.
- Other digestive-organ infections or nutritional problems causing poor growth.
Spread & risk factors
- Infected shrimp and contaminated material can introduce infection; ingestion and contact within a population allow spread.
- Contaminated water, sediment, equipment, and unscreened live or fresh feeds warrant biosecurity attention.
How to confirm the cause
- Ask an appropriate laboratory for a validated EHP-specific PCR test and tissue examination where indicated. The professional should select representative shrimp and suitable hepatopancreas samples.
- Discuss assay specificity, sampling, and repeat testing. A negative sample is not a guarantee for the whole batch; a PCR-positive environmental sample does not by itself prove viable infection.
Prevention: your practical checklist
Obtain traceable postlarvae with a documented, appropriate EHP screening plan.
Ask which pathogens any SPF claim covers and maintain biosecurity after purchase.
Keep nets, sampling trays, boots, and sludge tools assigned to individual ponds.
Plan between-crop sediment removal and sanitation with a qualified professional.
Use controlled water supplies and formulated feed; review live-feed risks with the hatchery.
What to do if you suspect a problem
Contact a qualified aquatic animal health professional and arrange laboratory sampling before changing management.
Record weight distribution, feed use, survival estimates, and pond identity for the assessment.
Restrict movement of shrimp, sludge, water, and equipment between affected and unaffected ponds.
Review realistic biomass and harvest options; discuss current, verified management options directly with CIBA or the professional.
What not to do
- Do not diagnose EHP from white faeces or size variation alone.
- Do not self-prescribe medicines or accept guaranteed clearance claims.
- Do not transfer apparently healthy survivors into another growing pond.
Farmer questions
Does every EHP infection cause white faeces?
No. EHP and white faeces syndrome overlap in some cases, but neither observation establishes the other. Test shrimp and investigate other digestive problems.
Are management options changing?
Yes. CIBA reported field validation of an EHP therapeutic in May 2026. That institutional announcement is not a prescription or a guarantee for an individual pond. Ask CIBA or your professional about current evidence and suitability.
Sources & further reading
Sources support the discussion above. Their inclusion does not mean these organisations reviewed or approved this article. Some references cover other shrimp species; the guide states limitations where relevant.
- 01Infection with Enterocytozoon hepatopenaei — Technical Disease Card ↗
World Organisation for Animal Health (WOAH); document header updated 30 September 2024
- 02
- 03A new and improved PCR detection method for Enterocytozoon hepatopenaei (EHP) based on a gene encoding a spore wall protein ↗
NACA; Centex Shrimp technical note, 2016
- 04ICAR-CIBA sensitized the shrimp farmers of Ramanathapuram, Tamil Nadu about Microsporidiosis (EHP) and White Feces Syndrome (WFS), their prevention and management on 11th May, 2026 ↗
ICAR–Central Institute of Brackishwater Aquaculture
AI-assisted source check: 16 October 2026, not professional approval. Reference dates refer to the documents, not their URL filenames or live disease status.
AquaGrow completed an AI-assisted technical-source and translation-consistency check on 16 October 2026. This is educational content, not an individual pond diagnosis, a prescription or an endorsement by ICAR-CIBA, NACA or WOAH. An independent clinical review has not been completed. Translations also await independent review by native-speaking aquaculture specialists.
This is a selected learning library, not a complete disease list or a statement that every condition occurs in Andhra Pradesh or Odisha. No live outbreak surveillance is provided.