Flu Update from Richard Newton at the AHT
Friday, July 5, 2019

In an email to the evg group Richard Newton warns of increasing flu confirmations and of horse owners seemingly ignoring guidance, The full email is below.

Dear Group

Following my last update two weeks ago, the AHT continues to report laboratory confirmed influenza outbreaks across Great Britain, with the total outbreaks now approaching 180 distinct foci so far this year. I include again monthly and weekly totals (noting week 27 of 2019 only covers 2 days in these data), which clearly highlight that June was a bumper period for EI, accounting in one month for just over a third of the year-to-date total!



It should be remembered that this is most likely to be an underestimation of the true extent of EI in Britain at the present time, with an unknown number of outbreaks probably going undiagnosed for a variety of reasons, not least that owners don’t always consult vets. 

In understanding the reasons for the now evident sustained week-on-week increase in numbers of confirmations of EI since the end of April, we probably can’t overlook the effect of increased movement and mixing of horses during the late spring and summer months as a contributing factor. Furthermore, where this involves attendance by animals that have not been vaccinated at events (here referring broadly to horse gatherings of any kind) which do not mandate EI vaccination as an entry requirement and/or police such a policy, then this is a recipe for effective and potentially escalating infectious transmission.  

We would use it only as an example as it is not unique but following travel and mixing of a large population of predominantly unvaccinated horses at Appleby Horse Fair in early June, there was a subsequent increase in the number of confirmed flu outbreaks, where links to this event were clearly cited by colleagues attending sick horses. Outbreaks with links to Appleby spanned all corners of the country, from Somerset, to Sussex and mid-Glamorgan to Tyne and Wear and these clusters are evident on the map of EI confirmations for June.



I am extremely grateful to my colleague Fleur Whitlock MRCVS for formulating the following advisories, which we consider are paramount if we have any chance of stopping the spread of EI in the UK horse population. You may not consider these entirely feasible in all situations but the veterinary profession is integral in this and we must continue to ensure owners and event organisers are made aware of the messages and detail contained below. 

Horses attending events
We re-iterate our major concerns regarding future scheduled events that do not require vaccination for attendance and as such our recommendations are:

• Ensure all horses attending events are vaccinated. We would strongly advise events only accept horses that have had a booster within the last 6 months (rather than annual) and also enforcing the minimum 5 day rule post vaccination (interval between last vaccine dose and competition entry to have some benefit from that vaccination).
• EI vaccination status should ideally be confirmed prior to arrival of all competitors. 
• Ensure there has been no recent history of infectious disease on competitors’ home yards, before they leave for the event. This could be in the form of a signed health declaration stating this and also ask owners to take and note down the horses temperature prior to travel. Encourage owners to be responsible and aware that even if their own horse appears ok, there is the potential for subclinical influenza infection from other infected horses on their yard.
• Advise owners on biosecurity at the competition and when they get back to their home premises too. This should include:
o Take own equipment, including water buckets and water. 
o Avoid communal troughs and do not share any equipment. 
o Prevent direct and indirect contact between horses. 
o Don’t allow horses to graze communal areas. 
o Avoid horse-to-horse contact and other people touching your horse. 
o Disinfect equipment, vehicles and boots after the event. 
o Continue to closely monitor horses for a few weeks after the event, including daily temperature monitoring. 
o Encourage owners to contact their vet at the earliest opportunity if they have concerns with their horse.

New arriving horses and good-practice at vettings
The veterinary profession are integral in promoting preventive measures to mitigate infectious disease transmission among all veterinary species, including equines. It is evident from our surveillance data that a very high proportion of the confirmed EI outbreaks this year are as a result of recent new arrivals bringing infection on to premises, either acquired from the exporting premises or during travel. Worryingly some of these had been noted to be coughing at pre-purchase examination prior to their arrival at the receiving premises and some had received a first EI vaccination in the few days preceding the EI diagnosis, with owners perhaps not being aware that a single first vaccination would not impart immunity.

Some sensible basic steps are as follows 
• Isolate animals immediately that develop clinical signs, including raised temperatures, which ideally should be being taken twice daily and systematically recorded so that changes in patterns are immediately obvious.  
• Quarantine all new arrivals, even when a horse appears outwardly healthy, ideally for 21 days, so that if they develop clinical signs they will not pose an infectious risk to the resident population. 
• Discuss the practicalities of isolation/quarantine facilities with your clients, offering advice on how to make an isolation area, even for yards where it appears impossible: 
o Use a separate stable (no shared airspace) or paddock with dedicated water source or set aside a stable block or double fence an area of field - isolate away from walkways, tape around the entrance, use clear signage, have handwashing and foot dip facilities available.
o Ensure the area is a minimum of 10 metres from other stables or paddock borders; ideally the longer the separation the better, especially for EI, however it does have to be practical and made use of.
o Make sure that there is no shared airspace with other horses 
o Use separate labelled equipment, a separate muck heap and separate handlers 
• Ensure new arrivals are vaccinated against EI, remembering that horses will only have protection from vaccination from two weeks after the second vaccine dose of the primary course. Make sure owners are aware of this and recommend that owners only accept new arrivals at least two weeks after the second vaccination.
• Discuss further laboratory infectious disease testing of quarantined new arrivals with owners, for example using serology to confirm a horse is not likely to be a strangles carrier. There may be merit in taking a nasopharyngeal swab from a horse within 48 hours prior to it leaving the exporting premises and testing it for EI by qPCR. 

Leading by example
Veterinary surgeons must lead by example. For those that have done, currently do or maybe haven’t been in farm animal practice since when they were a vet student, you should remember the very high levels of biosecurity compliance that are now expected of a farm vet. Why should equine practice be any different? By the way this is a rhetorical question before you rush to tell us why not!!

• Wherever possible, equine vets should only visit suspect infectious disease cases at the end of the day, as the last call, when not on call that evening. Encourage receptionists to take as much information down about a call and ask them to seek veterinary opinion if they have suspicions a case may be infectious, to see if it can wait till the last call and also ensure the treating vet has all the required equipment in the car including; coveralls, shoe covers, disinfectant e.g. Virkon powder sachets and the all-important nasopharyngeal swabs and transport media!
• Obviously all vets have ended up at that call with the horse unexpectedly presenting with overt clinical signs of suspected infectious disease. It is worth having a protocol in place for this eventuality, with appropriate equipment in your car to decontaminate afterwards.
• Optimise your biosecurity between routine calls, alcohol hand gel and wiping down stethoscopes as a bare minimum. Perhaps the steering wheel might benefit from a little clean too once in a while!?
• Discuss with colleagues about biosecurity at the practice and what protocols individuals adopt, identify any loopholes and share and adopt best practices between you. 
• EI has been confirmed this year on very isolated yards where the horses have not been off site but the owner has had contact with other horses, demonstrating that fomite spread has occurred. Questions worth asking at the practice therefore include 
o Do those handling sick in-patients also have their owner horses at home? 
o Do staff change clothes between work and seeing their own horses? 

Remember latest updates on EI in the UK and elsewhere are available at https://www.aht.org.uk/disease-surveillance/equiflunet and we have attached a couple of infographics that may be of help to your clients and feel free to share on social media.

Well done guys if you have managed to get this far and you haven’t thrown things at the screen! Fleur is more than happy if colleagues want to discuss any of this further (direct dial  to her desk is 01638 555664; fleur.whitlock@aht.org.uk) – thanks for your continued support. Please could somebody share this on Veterinary Voices Equine – many thanks. 

Richard and Fleur
Epidemiology and Disease Surveillance
Animal Health Trust

 

The Animal Health Trust have also made the following available which we would encourage you to share with horse owners.

Equine Flu Event Guide

View guide


Vaccinate, Isolate, Investigate poster

View poster


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