Location patterns and risk factors for Alabama Rot in UK dogs

Kim Stevens, Dan O’Neill, Rosanne Jepson, Laura Holm, David Walker and Jacqueline Cardwell have a paper published in Vet Record (1), available for free courtesy of Sci-Hub  sci-hub.tw/10.1136/vr.104892

AlabamaRot.co.uk blogged about the funding for this Kim Stevens managed project, in October 2017.

Abstract

“The annual outbreaks of cutaneous and renal glomerular vasculopathy (CRGV) reported in UK dogs display a distinct seasonal pattern (November to May) suggesting possible climatic drivers of the disease. The objectives of this study were to explore disease clustering and identify associations between agroecological factors and CRGV occurrence. … The majority of diagnoses (92 per cent) were reported between November and May while the number of regions reporting the disease increased between 2012 and 2017. Two significant spatiotemporal clusters were identified—one in the New Forest during February and March 2013, and one adjacent to it (April 2015 to May 2017)—showing significantly higher and lower proportions of cases than the rest of the UK, respectively, for the indicated time periods. A moderately significant high-risk cluster (P=0.087) was also identified in the Manchester area of northern England between February and April 2014. Habitat was the predictor with the highest relative contribution to CRGV distribution (20.3 per cent). Cases were generally associated with woodlands, increasing mean maximum temperatures in winter, spring and autumn, increasing mean rainfall in winter and spring and decreasing cattle and sheep density. Understanding such factors may help develop causal models for CRGV occurrence.”

When does CRGV occur?

See figure 1 below:

The heat map shows that the much higher prevalence of CRGV in November-May compared to June-October.

Where are most cases?

See Figure 3 below

CRGV by Breed

Of the five most commonly specified breeds in the study population (labrador retriever, Staffordshire bull terrier, Jack Russell terrier, cocker spaniel and German shepherd dog), three were under-represented among CRGV dogs: Staffordshire bull terriers, Jack Russell terriers and German shepherd dogs. Conversely, breeds that were over-represented among CRGV dogs were generally the less common breeds such as English springer spaniels, Whippet, Hungarian Vizsla, Flat-coated retriever and Manchester terrier. See Table 1 in the report.

Predicting CRGV location

 

Conclusion

“In conclusion, the results of this study suggest that gun dogs and hounds have an increased risk of developing CRGV in the UK, while toy dogs and terriers appear to be the breed groups least at risk. Specific breeds with increased odds of CRGV included Hungarian vizslas, flat-coated retrievers, whippets and English springer spaniels. As well as helping veterinarians develop an index of suspicion for the disease, an understating of the breeds at risk may help to develop causal models for CRGV, and potentially play a role in identifying the aetiology of the disease. However, further studies investigating the distribution of specific breeds and breed groups in the UK, and the factors driving these distributions, would help to determine whether the high-risk breeds and breed groups identified in this study are indeed inherently more disposed to being diagnosed with CRGV or whether the results stem from an increased proportion of such breeds in areas of greater risk.”

References

(1) Stevens, KB., Jepson, R., Holm, LP., Walker, DJ., Cardwell, JM. (2018) Spatiotemporal patterns and agroecological risk factors for cutaneous and renal glomerular vasculopathy (Alabama Rot) in dogs in the UK Veterinary Record Published Online First: 27 August 2018. doi: 10.1136/vr.104892

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”