Vibriosis (luminescent and non-luminescent)
The most common bacterial complex in shrimp ponds — often opportunistic on top of viral or stress damage.
Clinical signs
- Greenish bioluminescence in the pond at night (V. harveyi outbreaks) — most reliable field signal
- Empty guts, anorexia, and reduced feed response 24–48 hours before mortality climbs
- Reddish-brown gills and melanised lesions on the cuticle (shell disease)
- Loose, white or pale-yellow feces strings on the pond surface (often co-occurring with EHP)
- Tail necrosis, broken antennae and red-tail in juveniles
- Cumulative mortality 20–60% over 5–10 days; spikes after stress events (DO crash, salinity drop)
- Pale hepatopancreas with translucent tubules under field microscopy
Transmission
- Waterborne — Vibrio spp. are normal flora of brackish water; disease follows population blooms above ~10⁴ CFU/mL
- Sediment reservoir — organic load + temperature >28°C drives blooms from the pond bottom
- Oral via contaminated feed, especially wet/fresh feed and unautoclaved live feed
- Mechanical via shared nets, buckets and worker hands moving between ponds
- Opportunistic — almost every WSSV, AHPND, EHP or DO-crash event ends in a secondary Vibrio bloom
Diagnosis
- Field: night-time greenish glow at the pond edge = presumptive V. harveyi
- Lab: TCBS agar plating of pond water and hepatopancreas — green colonies (sucrose-negative) suggest V. parahaemolyticus/harveyi; yellow colonies (sucrose-positive) suggest V. alginolyticus
- Lab: total Vibrio count + green:yellow ratio — green colonies above 10³ CFU/mL is a warning, above 10⁴ CFU/mL is an outbreak threshold
- PCR for toxin genes (pirA/pirB) to rule in or out AHPND-type V. parahaemolyticus
- Antibiotic sensitivity testing should be done by lab — empirical dosing breeds resistance
Treatment & emergency response
- Cut feed by 30–50% immediately to reduce organic load feeding the bloom
- Apply Bacillus subtilis + B. licheniformis probiotics at 10⁶ CFU/mL of pond water — daily for 5 days
- Maintain DO above 5 mg/L with 24/7 aeration; Vibrio blooms accelerate under hypoxia
- Partial water exchange (10–20%) with disinfected water if salinity and biosecurity allow
- Antibiotic use only with a vet prescription, lab sensitivity report, and full withdrawal-period compliance — antibiotic residues cause EU/US/Japan export rejections
- If mortality crosses 30% before 60 DOC, emergency harvest is usually a loss; if after 70 DOC with ABW >15 g, partial harvest can recover 50–70% of revenue
Prevention
- Strict pond preparation: full dry-out + CaO at 1,000 kg/ha + 14-day sun-drying between cycles
- Probiotic program from day 1 — Bacillus spp. weekly, with intensified dosing during temperature peaks
- Weekly TCBS Vibrio counts logged per pond; act when green colonies exceed 10³ CFU/mL
- Stable water quality — sudden salinity, pH or temperature swings precede most blooms
- Reduce feed by 30% during the first 25 DOC and after every stress event
- Disinfect intake water (chlorine 30 ppm, hold 24 h, dechlorinate) when source water Vibrio counts are elevated
- Source PLs only from hatcheries with documented Vibrio screening protocols
Biosecurity checklist
- Foot baths (200 ppm chlorine) at every pond entry, refreshed daily
- Dedicated nets, buckets and aerators per pond — colour-code to prevent cross-use
- No movement of workers from a Vibrio-positive pond to a healthy pond on the same day
- Disinfect feed scoops and check trays between ponds (70% alcohol or 200 ppm chlorine dip)
- Quarantine and TCBS-test any new PL batch for 5 days before stocking
- Reject mouldy or musty-smelling feed bags — fungal contamination compounds Vibrio outbreaks
- Log daily mortality + feed response + DO; any anomaly triggers a same-day TCBS plate
Regional prevalence
See where Vibriosis is being reported right now across India and Southeast Asia, with weekly trend lines and per-district drilldowns.
Open the heatmap →Frequently asked questions
What is vibriosis in shrimp farming?
Vibriosis is a bacterial disease complex caused by several Vibrio species — V. harveyi, V. parahaemolyticus, V. alginolyticus and others. These bacteria are naturally present in all brackish water. Disease begins when populations bloom above roughly 10⁴ CFU/mL, usually after a stress event like a DO crash, salinity drop, or co-infection with WSSV or EHP. Untreated outbreaks cause 20–60% mortality.
What does luminescent vibriosis look like in a pond?
V. harveyi produces a greenish-blue glow visible at the pond edge at night. If you can see a faint glow when you stir the water or shine a torch on dying shrimp, that's the most reliable single signal of luminescent vibriosis. Confirm with TCBS plating the same day and start probiotic + feed-reduction protocols immediately.
Should I use antibiotics to treat vibriosis?
Generally no. Antibiotic residues cause export rejections that often cost more than the disease itself. EU, US and Japanese importers test for chloramphenicol, nitrofurans and fluoroquinolones; a single positive batch can shut a farm out of a market. Use probiotics (Bacillus spp.), feed reduction, aeration and water management first. Reserve antibiotics for vet-prescribed cases with documented sensitivity and full withdrawal compliance.
How do you read a TCBS plate for shrimp Vibrio?
TCBS agar is selective for Vibrio. Green colonies (sucrose-negative) indicate V. parahaemolyticus or V. harveyi — the more dangerous group. Yellow colonies (sucrose-positive) indicate V. alginolyticus and similar — generally less virulent. Count colonies per mL of pond water: above 10³ CFU/mL of green colonies is a warning, above 10⁴ CFU/mL is an active outbreak threshold and demands immediate intervention.
Can vibriosis spread from shrimp to fish?
Some Vibrio species (V. anguillarum, V. vulnificus) cause disease in both shrimp and fish — particularly in polyculture or shared-water systems. Most shrimp-pathogenic strains (V. harveyi, AHPND-causing V. parahaemolyticus) do not cause large fish kills, but the bacteria can still colonise fish guts. Treat shared-water systems as a single biosecurity unit.
Is vibriosis dangerous to humans?
V. parahaemolyticus and V. vulnificus can cause foodborne illness in humans if seafood is undercooked or wounds are exposed to contaminated water. Properly cooked shrimp is safe. The economic risk for farms is export rejection on residue testing, not human disease from farm exposure.
Catch Vibriosis before it costs a cycle
CAMARON's Disease Vision module flags Vibriosis from a single farm photo, ties findings to the regional heatmap, and walks you through the protocol.