Fish Disease-SVC

NACA Information Sheets - Spring Viraemia and Carp

SVC and Fish Transfers

SVC is a fishery killer disease, to be avoidedIt is a sad fact of life that we now have significant numbers of SVC carrying Carp in this country. Given that our existing stock of fish is very susceptible to this disease, what can we as anglers and fishery owners do to minimise the risks? The simple answer is that we should make every attempt to isolate existing stock from potential SVC infected fish. However this is not as easy as it sounds, as SVC carrying fish can look perfectly healthy. This problem is compounded by the fact that the disease tends to manifest itself as water temperatures rise in the spring (hence the name). Thus healthy looking fish can be stocked in the autumn/winter and no problems arise until the following spring.

Health Checks

All fish introductions currently require a Section 30 fish movement order. Such per

The situation is further complicated by the fact that fish may now be legally imported from certain areas of the continent. In theory these fish have to come from 'approved zones' that have been certified as SVC free for at least 2 years. In practice it appears that fish farms with 'approved' status are possibly being used as holding tanks for fish from other sources. Thus there is no guarantee that fish are SVC free, regardless of the fact that they come from an 'approved zone'.

Illegal Imports

The death of big UK bred carp available for stocking has unfortunately opened the way for a significant growth in illegal imports. Border controls are almost non existent and so the risk of being caught is small. Furthermore if somebody is caught, the fines are insignificant. Some fish dealers are now offering to acquire big carp to order for their clients on a 'no questions asked basis'. Thus the fishery owner requests a few 30's and a 40 and a few weeks later an unmarked vehicle appears and said fish are released into the lake. This scenario involved neither import consent, nor Section 30 permission.

Safe Stocking

Always when stocking seek health certificates for all fish to be introducedGiven the black scenario I have painted, can a fishery still obtain large carp that are SVC

However, if you must stock, then please be aware of the risks involved and try and minimise the danger:

(a) never even consider illegally stocking any fish

(b) consult your local EA Fisheries office for information about reputable dealers.

(c) ask potential dealers serious questions about where the fish are from and where the dealer has recently stocked fish from the same source. Then go and talk to the other fishery owners who have received similar fish. You will probably have to order fish in advance from a dealer who is reputable.

(d) ensure the fish have all possible NRA health certification. If you are concerned about the possibility of SVC with UK sourced fish, then consider arranging your own SVC check.

(e) be extra careful with fish that have been imported from abroad, or sold onto you from a water where imports have occurred. There is a nasty trend for illegally imported fish to be stocked and then sold on as soon as disease manifests itself

(f) do not accept fish that arrive on site in a poor state of health. If possible quarantine the new fish with a small number of your existing stock

Keeping SVC out of your waters

It goes without saying that you should rigorously enforce fishery rules to the illegal introduction of any live fish. Transferring livebaits from one water to another is illegal, it can also be very dangerous.

It is suggested that SVC can be transferred from one water to another via wet nets etc. there is no recorded evidence of this occurring

Some waters now ban sacks and provide their own unhooking mats to stop anglers bringing their own. It should be stressed that drying out of the above items will kill any viruses present. Wet sacks and nets are the problem.

Recommended disinfectants include FAM 30 (dilute at I part to 100 of water) or Wescodyne (1.5 parts per 100 of water). It is suggested that items are immersed for 15 minutes! These disinfectants come in bulk and are not cheap, 25 litres of Wescodyne costs £100. It might be an idea for local water owners to share a canister between them. For more details contact your local EA fisheries office.

The Future

It is probable that the current Section 30 fish movement regulations will be radically changed soon. The likely future scenario is that the EA will confine itself to the control of alien species. Thus Section 30 consent will simply give an owner the right to stock a particular species. Beyond that, it will be the responsibility of the buyer to health check his incoming stock fish. Therefore you (as a potential buyer) will be able to be as vigilant (or otherwise) as you like in attempting to keep your waters disease free. There will be an attendant growth in the number of independent fish disease laboratories, offering their services to fishery owners.


Stocking any water with big carp is fraught with danger. If you must do it, proceed with extreme caution. Many water owners have already found out the hard way that illegal stocking can be catastrophic. It could happen to you.

If commercial pressures don't force you to take such risks a more sensible route is to purchase smaller fish from bona-fide British suppliers who breed the fish themselves.

The bottom line is that there are now so many SVC carrying fish in this country that there is little point in trying to keep it out. Ultimately over the next decade or so, we will have to replace our existing UK stock with SVC resistant fish from elsewhere. This is proving to be a very painful process.