18 Aug 2023
A case – in Craigavon, County Armagh – is the first in Northern Ireland for nearly four years, but its timing is outside the recognised November to May season for the disease.
Most CRGV cases fall from November to May, with woodlands one of the possible environmental factors identified. Image: © tiena / Adobe Stock
A leading expert has raised concerns that changing weather patterns could lead to more cases of an often-fatal canine disease being recorded outside what is currently recognised as its typical season.
The cautionary message was delivered following confirmation of the death of a dog in Northern Ireland that had contracted cutaneous and renal glomerular vasculopathy (CRGV), also known as Alabama rot.
But another team of scientists who have been investigating the cause of the disease said they are continuing to make progress towards identifying its source.
Details of the latest incident, which involved a three-year-old male French bulldog, were released through Anderson Moores Veterinary Specialists (AMVS) in Hampshire on 11 August.
The case – recorded in Craigavon, County Armagh – is the first of the disease anywhere in Northern Ireland for nearly four years, according to the practice’s online monitoring map, and only the fifth since the first case was recorded there in 2014.
But its timing is also unusual in that it occurred roughly in the middle of the period outside the recognised season for the disease, which runs from November until May.
Josh Walker, co-lead of the AMVS research unit into CRGV, said certain weather patterns – including higher mean maximum temperatures outside the summer months and increased mean winter and spring rainfall totals – had been identified as potential risk amplifiers in previous research work on the disease.
He added: “It is possible that as climate patterns and weather changes, we may see variability in this.”
The vast majority of the 295 CRGV incidents recorded in the UK, since it was first discovered in the country in 2012, occurred during the disease’s regular season.
Analysis carried out by Dr Walker and colleagues in 2019 found that, out of 178 confirmed cases up to June of that year, only 15 (8.4%) fell outside the usual season.
The newest case is the eighth out-of-season incident to have been recorded since then, following five in 2020 that included two in June, one in August 2021 and another in October of last year.
Although the UK as a whole experienced its hottest June on record this year, exceeding previous levels dating back to 1884, Northern Ireland then endured its wettest recorded July, beating the previous peak that had stood since 1936.
Other environmental factors, including woodlands and areas with lower density cattle and sheep populations, have been thought to have a potential connection to the disease for several years, in addition to weather patterns, with significant clusters identified in both the New Forest and the Manchester area.
Dr Walker said he could not make a broader comment about the potential implications of climate change for the disease.
But he added: “If increasing periods of the same types of weather (increasing mean rainfall, and so forth) are identified, this may be of concern for increasing risk and certainly increasing winter temperatures would be one of the noted associations.”
The new case, which is the first to be confirmed in Northern Ireland since late 2019, and the fifth overall across the UK so far this year, has prompted renewed pleas for vigilance among dog owners against the disease, which is known to affect the kidneys and has a mortality rate of up to 90%.
Hopes of a potential breakthrough in the understanding of CRGV were raised earlier this year when a team of scientists revealed they had identified what they believed could be a potential source of the disease.
Project lead Fiona Macdonald said: “Our investigations at the University of Bristol Veterinary School are ongoing and we are making progress as to the identity of the causal agent.”
Clinical Assist