|Spring Viremia Of Carp - Testing and Annihilation
Imagine you're standing in your back yard looking at your fish pond when two men in a sinister looking sedan drive up and ascend your driveway.
"Are you the owner of this pond?"
"Why yes I am,” you reply.
He holds out a piece of folded paper and says "This is to serve as notice that these premises are under quarantine for Spring Viremia of Carp, and will shortly be depopulated. You may from this point forward only keep fish here under the purview of our organization and you will not keep fish here until we give you clearance to do so."
Could this happen to you? Yes it could.
First, I would like to finish out my thoughts on the above scenario, which is surely uncommon but nevertheless possible. The virus that causes such a ruckus is called Spring Viremia of Carp or Rhabdovirus carpio. It can kill tens of carp in a group of a hundred. Yes, I said SVC might be responsible for the loss of whole hand nets full of fish affected by by this virus. My professional experience with SVC has been that SVC can kill nearly 5% of affected fish. Wow! Imagine losing five out of every hundred fish to this virus. Worse, because the virus may be endemic in a fish population, you could lose over five percent of your livestock every Spring to this virus and probably not even notice. Those are the worst kinds of losses because they remain unmeasured and they don't calculate into your losses or expenses. Fortunately, there is a treatment that eliminates the virus affecting the fish. Testing the fish for SVC can detect it with some reliability. Fish with the virus are (as required by law) reported to Federal agencies and then their treatment by incineration or burial can begin. Virus problem solved. You will be spared the anxiety of taking any further risk of selling infected fish to the public because your business will be terminated and you will be re-opened at the convenience of the regulators.
How does SVC look?
An infection with SVC looks like a bacterial infection because the virus by itself in vivo is not usually effective at killing pond fish without a bacterial co-morbidity. So the signs are indistinguishable from bacterial sepsis, dropsy or furunculosis. Other signs that suggest the virus may be present on your lot can include dead or dying fish in small numbers over the course of years, making it indistinguishable from the normal operation of a fish business.
The purpose of my discussion of Spring Viremia of Carp is to try and convey my opinion and experience with this rarely encountered virus. This experience comes directly from a fish farmer whose fish were diagnosed with SVC, who told me that they were losing a few fish in a particular pond and "just to be on the safe side" they sent fish out for diagnostics. By the time the results came back as SVC - they'd lost a few fish and sold the rest - it was twelve weeks after the fish were showing some symptoms that the government came into their lots and shut them down.
The upshot to the story is that the government has since passed into law an indemnification policy and payments are made to farmers who lose everything to the test and elimination programs instituted on their farms. Whether the lost fish are accurately assessed for financial impact or whether you can survive being closed-down until the government indemnifies you is a risk you can avoid.
I personally and professionally recommend that until more is known about the prevalence of SVC by the government that you not "elect" to have this testing run. IN fact, since the fish farm that was closed down by SVC never asked for that test in the first place, I think you should take the time to write "No SVC Testing" on your formwork as supplied to your diagnostic laboratory.
Recap: Spring Viremia of Carp is a reportable viral disease of cyprinids including Goldfish and Carp. The impact of the virus on your livestock is not catastrophic, having unknown morbidity and usually mild mortality. The regulatory effect of the discovery of the virus on your farm lot is catastrophic with the assignment of 100% morbidity and therefore 100% mortality. I acknowledge that I am trivializing the virus, but I am not trivializing the regulation of it.