Aeromonas hydrophila bacteria not ruled out as Alabama Rot cause has covered reports about Aeromonas hydrophila here, here and here. Vet Fiona Macdonald hypotheis is that Aeromonas hydrophila bacteria may be a factor in triggering Alabama Rot when conditions are rainy and cold.

The Vet Times report:

Specialist vet studies bacteria cause of Alabama rot Vet Fiona Macdonald is researching whether Aeromonas hydrophila is a link to identifying cause of deadly canine disease. A specialist fish vet is investigating an organism described as “a possible stepping stone” to identifying the cause of one of the UK’s most baffling and lethal canine diseases.

Fish vet Fiona Macdonald is researching whether Aeromonas hydrophila, a heterotrophic, Gram-negative, rod-shaped bacterium, present in water sources and soil, might be involved in the aetiology of CRGV.

In a document sent to Veterinary Times entitled “CRGV (Alabama rot) – an organism of interest?”, Dr Macdonald explained: “There is a suspicion initial cases of CRGV occurred in areas with substantial amounts of water as a result of unusually high rainfall; both running and standing water was close to 4°C for some weeks around the time of the cases.

“To date, dogs appear to be the only species affected, with no reported cases in wild ponies, foxes, cattle or deer. There have been recorded cases of infection with A hydrophila in dogs, which mirrored Leptospira infections, and this pathogen has been on the list of possible causes of CRGV since early manifestations of the problem.”

Dr Macdonald is receiving funding for her work from the New Forest Dog Owners Group, and is appealing for help from UK vets.

She said: “I want blood samples from suspected CRGV cases and I’m happy to send out swabs along with a sampling protocol to any vet for them to swab any suspicious lesions. Email me at”

David Walker, from Anderson Moores Veterinary Specialists, and the UK’s leading authority on CRGV, said: “It’s a nice piece of work… I’m hoping she publishes because it’s a possible stepping stone for either her, or others, to take on the work and truly include or exclude this organism in the Alabama rot investigation.””

The International Animal Health Journal (1) said:

“A bacterium that causes ulcerative skin lesions and kidney failure in fish could be linked to cases of Alabama rot in UK dogs, current research suggests.

Fish vet Dr Fiona Macdonald is co-ordinating a study into whetherAeromonas hydrophila could be a possible cause of cutaneous and renal glomerular vasculopathy (CRGV), also known as Alabama rot.”

The cause is not known yet…

“While the cause is not yet known, it appears to have a seasonal aspect, with most cases occurring between November and June. Initial cases occurred in areas with substantial amounts of water, as a result of unusually high rainfall, during cold weather. Both running water and standing water were 4ºC for some weeks at the time of the cases.”

Does A hydrophila grow in skin lesions causing Alabama Rot?

“A hydrophila was first recorded in dogs in 1995. It is known to cause ulcerative skin lesions in both ornamental and farmed fish, with subsequent kidney failure. The UK strains prefer cold, which could be why it grows in the skin lesions – as they are cooler than the rest of the body.”

A test for A hydrophila antibodies

“Diagnostic laboratory BioBest, in Edinburgh, developed a specific test for A hydrophila antibodies in serum. Dr Macdonald says a significant number of blood samples submitted from suspected CRGV cases, strongly indicated an immune response to the organism. The samples came from dogs living in rural areas across the UK, from southern Scotland to Devon.”

But the evidence for A hydrophila is weak with only one case

“Specialist transport medium swabs have also been sourced to sample skin lesions on first presentation to a veterinary surgeon. These are subjected to specific culture conditions for Aeromonads. So far, Dr Macdonald says there has been only one positive isolation of the organism from a swab taken from a suspect lesion. This dog also produced a positive antibody response to the organism.”

Research thus far has also involved testing canine kidney cells in tissue culture to determine if there are any effects associated with the A hydrophila. Dr Macdonald says the theory is that toxins from the organisms cause kidney problems in affected dogs, rather than direct infection by the organism itself. This could explain why the organism has never been isolated so far in affected dog kidneys.

Results show that both the medium in which the organism has been grown, and the inactivated organism, killed the dog kidney cells in tissue culture – even after significant dilution. Dr Macdonald says this goes a long way to confirming the involvement of bacterial toxins.

Going forward, the project needs many more samples to draw firm conclusions, but the early results have been described as ‘very promising’.


  1. 1) International Animal Health Journal (accessed 30th January 2018)

Alabama rot dog disease cases mostly occur in autumn/winter

The BBC report Royal Veterinary College researcher Dr Kim Stevens who confirms that about 60% of cases of Alabama rot, which has killed more than 100 dogs in the UK, occur in the first three months of the year.

New research by Kim Stevens has started to try and discover more about the risk factors and spread of the disease. The cause of the disease, which first occurred in the UK in 2012, is still unknown. However, researchers have found there are more cases in autumn and winter. Most deaths caused by the disease have happened in Hampshire, Dorset and Greater Manchester*.

The disease causes lesions on the skin and occasionally in the mouth. Some dogs can also develop life-threatening kidney failure.

Dr Kim Stevens, of the Royal Veterinary College, said her research, expected to conclude by the end of the year, would not identify the specific cause of the disease. She said it was instead designed to look for geographical patterns, as well as environmental and climatic risk factors. A “very obvious” pattern already found was linked to seasons, she added:

“There are limited cases over the summer whereas everything starts to pick up in November and at least 60% of the cases occur in the first three months of the year, so it’s very much an autumn/winter pattern that we’re looking at.”

UK dog deaths from Alabama rot since 2012

Berkshire 2
Cheshire 4
Cornwall 1
County Durham 2
Cumbria 1
Devon 4
Dorset 10
Dumfries and Galloway 1
East Sussex 3
Greater Manchester 12
Hampshire 18
Kent 2
Lancashire 2
Lincolnshire 1
London 3
Monmouthshire 5
North Yorkshire 1
Northamptonshire 1
Nottinghamshire 2
Shropshire 1
Somerset 2
Staffordshire 2
Surrey 6
Warwickshire 1
West Sussex 3
West Yorkshire 2
Wiltshire 3
Worcestershire 5
Wrexham 1
Source: Royal Veterinary College/Stop Alabama Rot

*  from the list of dog deaths by county, 40 of the 101 confirmed deaths since 2012 occurred in Dorset, Hampshire or Greater Manchester.

Epidemiology and cause of Alabama Rot project

First some definitions. Epidemiology is defined by Oxford Dictionaries as “the branch of medicine which deals with the incidence, distribution, and possible control of diseases and other factors relating to health”.  It is also the study of the causation of epidemic diseases according to Wikipedia. And CRGV is the scientific name for Alabama Rot.

This week the Alabama Rot Research Fund (ARRF) have reported funding an Alabama Rot / CRGV Epidemiology project by Dr Kim Stevens:

Continue reading “Epidemiology and cause of Alabama Rot project”

Google Trends – Alabama Rot

Awareness about Alabama Rot has peaked since David Walker of Anderson Moores went on Breakfast TV on 10th May to discuss the disease. The last maximum peak was in January 2014 when signs about Alabama Rot were placed in New Forest car parks.

Google Trend – Alabama Rot – Last 5 years

Interest over time

Numbers represent search interest relative to the highest point on the chart. A value of 100 is the peak popularity of the term. A value of 50 means that the term is half as popular. Likewise, a score of 0 means the term was less than 1% as popular as the peak.

Anderson Moores thank – Reading May 10th Conference

I attended the Reading Alabama Rot conference on Wednesday 10th May 2017. The conference was organised by David Walker and Laura Holm from Anderson Moores. There were 30 attendees and Bayer kindly paid travel expenses.

Today I received a very nice email from Anderson Moores:

Subject: RE: May 10th Conference

Dear Chris

David and I would like to extend our sincere thanks to you for attending the meeting yesterday.

Your input was very valuable and we really appreciate you making time to be there. Thank you also for taking time to look into and print off the case distributions by month / season.

Thank you so much again,

With kindest regards,

Laura and David

Laura Holm BVM&S CertSAM MRCVS
RCVS Advanced Practitioner in Small Animal Medicine

David Walker BVetMed (Hons) DipACVIM DipECVIM-CA MRCVS,
American and European Specialist in Small Animal Internal Medicine

Information about the Reading conference will be posted online soon.

Chris Street BSc MSc

Bransgore, Dorset

Environmental factor triggers Alabama Rot in dogs with an intrinsic disposition

The Reading Conference on Alabama Rot tomorrow (Wednesday 10th May 2017) is being organised by David Walker from Anderson Moores Veterinary Specialists (AMVS).

In a 13-minute report on Sunday 7th, May 2017, David Walker spoke to Rachael Garside of BBC Radio Wales ‘Country Focus’ programme (from 6m 45s). He said:

  • In the 1980s only greyhounds in Alabama got Alabama Rot
  • No greyhounds in the UK have got Alabama Rot
  • Alabama Rot has not ‘spread’ – “it has been everywhere the whole time” since 2012. The localisation in the New Forest initially arose due to awareness of the disease by vets in that area since AMVS of Winchester had been talking to local vets. (8m 33s)
  • Damage to smaller blood vessels caused by blood clots causes organs, like the kidney, to fail and to cause skin sores, typically below the elbow or knee in dogs.
  • The true cause of the disease is not known, despite incredibly hard work looking for infectious agents such as bacteria, viruses and fungi. We’ve also looked for toxins in the dog and the environment. (10m 06s)
  • Alabama Rot / CRGV has some similarity to some diseases in people so we can use this human data to consider how to approach the disease in dogs.
  • With 98 reported confirmed cases of dogs that have lost their lives across the UK since 2012, Alabama Rot is a rare disease. [8.5M UK dog population] (11m 06s)
  • “We strongly suspect there is an environmental trigger to Alabama Rot” (11m 06s)
  • Since hundreds of dogs will walk in an area but maybe only one dog will contract Alabama Rot, it may be that dogs that have been infected with Alabama Rot have some intrinsic predisposition to the disease and the environmental trigger.
  • Washing dogs legs after a walk is not scientifically based advice – but it can’t do any harm. (12m 02s)
  • We need more money to do research to try to improve survival rates and find the cause so that preventative measures can be introduced. (12m 57s)

“We strongly suspect there is an environmental trigger to Alabama Rot. It may be that dogs that have been affected have some intrinsic disposition to Alabama Rot…” (11m 06s)

In addition, Radio 4 Today Programme (from 2 hours 57m 30s) had a 2-minute report by Gabrielle Williams whose dog died in March 2017 and David Walker.