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Notifiable koi diseases

By the koi.wiki editorial team · Updated

Key facts: Notifiable (or reportable) diseases are conditions that must by law be reported to animal-health authorities when diagnosed in fish, including koi; koi herpesvirus (KHV) and spring viremia of carp (SVC) are the two viral diseases most commonly listed in this way[1][2][3].
A notifiable disease, also called a reportable disease, is one that must by law be reported to the proper federal and state or national officials when positively diagnosed[3]. The World Organisation for Animal Health (WOAH), the global authority on animal health, maintains listed disease chapters covering aquatic animals, including koi herpesvirus disease and infection with spring viraemia of carp virus[1][2].Requirements differ by country. The United Kingdom, the United States and Canada each have their own legal frameworks that determine which fish diseases must be reported and to whom, and the specific obligations placed on keepers and facilities can vary considerably between jurisdictions[4][5][6].

What “notifiable” means

In general terms, a notifiable or reportable disease is a disease which must, by law, be reported to the proper officials when positively diagnosed[3]. According to Wikipedia, animal disease notification internationally is monitored by WOAH, while individual countries layer their own domestic legal requirements on top of this global framework[8]. In the United Kingdom, notification of animal diseases is regulated under the Animal Health Act 1981 and related orders, with aquatic animal diseases such as KHV specifically covered by the Aquatic Animal Health (England and Wales) Regulations 2009[4][8].

Koi herpesvirus (KHV)

Koi herpesvirus disease, caused by a DNA herpesvirus also called Cyprinid herpesvirus 3 (CyHV3), is listed by WOAH and is a notifiable disease in the United Kingdom, where it must be reported immediately to the Fish Health Inspectorate (FHI) at Cefas[1][4]. KHV is present in Great Britain and outbreaks occur most summers in both recreational fisheries and, occasionally, ornamental koi, at water temperatures between about 16°C and 29°C (61–84°F)[4]. Since the first reports of KHV in Israel and Germany in 1998, the disease has spread to most continents, including Europe, Asia, the Middle East, Southern Africa and North America[9].In the United States, KHV is considered widespread rather than exotic. The US Department of Agriculture’s Animal and Plant Health Inspection Service (USDA APHIS) asks accredited veterinarians and laboratories to report KHV cases to the state’s area veterinarian-in-charge and the state veterinarian, but, unlike SVC, not every US KHV outbreak is notified onward to WOAH[3]. By contrast, one Southern Regional Aquaculture Center (SRAC) publication states plainly that KHV is not a reportable disease, though it notes the disease can still kill many or all fish at an affected facility and that depopulation and disinfection are recommended if it is confirmed[10]. This is a notable disagreement between sources: the UF/IFAS EDIS and WOAH materials describe KHV reporting obligations to US state and federal officials, while the SRAC fact sheet characterizes KHV as not reportable; readers in the United States should check current requirements with their state veterinarian[3][10].

Spring viremia of carp (SVC)

Spring viremia of carp (SVC), caused by the rhabdovirus Sprivivirus cyprinus, is listed as a notifiable disease by WOAH in the Aquatic Animal Health Code and is also notifiable in the United States, where suspect or confirmed detections must be reported to USDA APHIS Veterinary Services[5][2]. Within the US, SVC is treated as a foreign or exotic disease not normally present in susceptible species, so any detection triggers notification by USDA APHIS to WOAH once confirmed[3]. SVC was first reported in koi and feral carp in the United States in 2002, after having historically been a problem in Europe, the Middle East and Russia[5].In Canada, spring viraemia of carp is a federally reportable disease: anyone who owns or works with aquatic animals and knows of or suspects SVC in those animals is required by law to notify the Canadian Food Inspection Agency (CFIA)[6]. The disease is also on Florida’s state list of reportable animal diseases[5]. If SVC is confirmed at a facility, a state or national authority may quarantine the site while the extent of depopulation, cleaning and disinfection required is determined[10][5].Carp pox, caused by a different herpesvirus (Cyvirus cyprinidallo1, previously called Cyprinid herpesvirus 1), affects common carp and koi and typically produces smooth, raised “candle-wax drippings” growths on the skin and fins of older fish. Unlike KHV and SVC, carp pox is not a reportable or notifiable disease in the United States[3]. A comparison published by UF/IFAS EDIS notes that KHV, SVC and carp pox differ in their viral agent, species affected, optimal water temperature range and transmission routes, which has significant management and regulatory implications for each[3].

How the UK applies controls

KHV is present in Great Britain and classified as a ‘Listed’ (also referred to as ‘notifiable’) disease under the Aquatic Animal Health (England and Wales) Regulations 2009, with its status set out in Regulation 1251/2008 as amended[4]. Outbreaks have been subject to statutory controls in the UK since 2007, and the UK maintains an ongoing surveillance programme for the disease[7]. Where laboratory testing confirms KHV disease at a site, the FHI applies statutory controls known as a confirmed designation, which can include restrictions on moving aquatic animals, eggs and gametes into, out of, or within the designated area without written FHI consent, and requirements to notify the FHI of further mortalities or of any intended physical changes to the site[7]. Disease control measures following confirmation may also include enhanced biosecurity, culling of fish, and cleaning and disinfection of the premises[7]. There is no treatment for KHV, and the GOV.UK guidance states prevention and good biosecurity are the best approach, including not buying fish of unknown origin[4].

Common questions

Is koi herpesvirus (KHV) notifiable everywhere?
KHV is a listed, notifiable disease in the United Kingdom, where it must be reported to the Fish Health Inspectorate immediately[4]. In the United States, UF/IFAS EDIS describes KHV reporting obligations to state officials, while a separate SRAC fact sheet states KHV is not a reportable disease there, so requirements should be confirmed locally[3][10].
Is spring viremia of carp (SVC) notifiable?
Yes. SVC is listed by WOAH as notifiable and is reportable in the United States to USDA APHIS, federally reportable in Canada to the CFIA, and notifiable in the UK[5][6][2].
Is carp pox a notifiable disease?
No. According to UF/IFAS EDIS, carp pox (Cyvirus cyprinidallo1) is not a reportable or notifiable disease in the United States, unlike KHV and SVC[3].
Who do I contact if I suspect a notifiable koi disease in England or Wales?
GOV.UK states that suspected listed diseases, including KHV, must be reported immediately to the Fish Health Inspectorate (FHI) at Cefas, by phone or email, including an out-of-hours emergency line[4].
Can notifiable koi diseases be treated?
There is no treatment for KHV, and antiviral drugs and vaccines are not available for SVC either, so prevention, biosecurity and, where confirmed, depopulation and disinfection are the recommended responses[4][5].

References

  1. ^ Koi herpesvirus disease - WOAH - World Organisation for Animal Health. World Organisation for Animal Health. woah.org/en/disease/koi-herpesvirus-disease/. Retrieved November 2026.
  2. ^ Spring viraemia of carp - WOAH - World Organisation for Animal Health. World Organisation for Animal Health. woah.org/en/disease/spring-viraemia-of-carp/. Retrieved November 2026.
  3. ^ UF/IFAS EDIS VM113: Koi Herpesvirus Disease (KHVD). University of Florida IFAS Extension (EDIS). ask.ifas.ufl.edu/publication/VM113. Retrieved November 2026.
  4. ^ Koi Herpesvirus (KHV) - GOV.UK. UK Government. gov.uk/government/publications/koi-herpesvirus-khv/koi-herpesvirus-…. Retrieved November 2026.
  5. ^ UF/IFAS EDIS VM106: Spring Viremia of Carp Virus (SVCv). University of Florida IFAS Extension (EDIS). ask.ifas.ufl.edu/publication/VM106. Retrieved November 2026.
  6. ^ Spring Viraemia of Carp - inspection.canada.ca. Canadian Food Inspection Agency. inspection.canada.ca/en/animal-health/aquatic-animals/diseases/repo…. Retrieved November 2026.
  7. ^ Outbreaks of Koi herpesvirus (KHV) disease in 2026 - GOV.UK. UK Government. gov.uk/government/news/outbreaks-of-koi-herpesvirus-khv-disease-in-…. Retrieved November 2026.
  8. ^ Notifiable disease (Wikipedia). Wikipedia. en.wikipedia.org/wiki/Notifiable_disease. Retrieved November 2026.
  9. ^ Manual of Diagnostic Tests for Aquatic Animals, ch. 2.3.6 Koi herpesvirus disease (WOAH). World Organisation for Animal Health. woah.org/fileadmin/Home/eng/Health_standards/aahm/current/2.3.06_KH…. Retrieved November 2026.
  10. ^ SRAC Publication No. 7201: Species Profile: Koi and Goldfish. Southern Regional Aquaculture Center. srac.msstate.edu/pdfs/Fact%20Sheets/7201%20Species%20Profile-%20Koi…. Retrieved November 2026.