Disease outbreaks rock the United Kingdom: COVID-19 variants, Bird Flu and Koi Herpesvirus

The United Kingdom is currently grappling with a concerning surge in disease outbreaks that demand immediate attention and thorough containment measures.

These outbreaks span various diseases, each presenting unique challenges to public health and the welfare of both animals and humans. Among the most pressing issues are the emergence of new COVID-19 variants, the persistent avian influenza cases and the reoccurrence of Koi Herpesvirus (KHV) disease.

Unveiling the New COVID-19 Variant: BA.2.86 Raises Alarm

The United Kingdom Health Security Agency (UKHSA) has issued a preliminary risk assessment regarding the latest SARS-CoV-2 variant, BA.2.86. This variant was first detected on August 18, 2023, within the UK's borders and has since spread to other nations, including Israel, Denmark and the United States.

Designated as V-23AUG-01 by UKHSA for monitoring purposes, this variant boasts an unusually high number of mutations. Genetically distinct from both its likely precursor, BA.2, and the currently circulating XBB-derived variants, BA.2.86's arrival has prompted concern due to its potential implications.

Though currently just one confirmed case of BA.2.86 within the UK has been documented, the fact that the infected individual had no recent travel history suggests a potential for community transmission. Investigative efforts are now underway to ascertain the extent of this transmission. However, lack of sufficient data prevents an assessment of BA.2.86's severity and its potential for immune evasion in comparison to other existing variants.

Avian Influenza Casts a Long Shadow Over the UK

Avian influenza, commonly known as bird flu, continues to plague the United Kingdom, impacting both poultry and wild bird populations. According to the latest data, there have been a total of 199 confirmed cases of highly pathogenic avian influenza (HPAI) H5N1 since October 1, 2022.

These cases are distributed across the UK's regions as follows: 158 cases in England, 32 cases in Scotland, eight cases in Wales and one case in Northern Ireland.

Since the outbreak commenced in October 2021, England alone has reported 292 cases of HPAI H5N1. In addition, one confirmed case of low pathogenic avian influenza (LPAI) H7N3 has been documented in Scotland on March 20, 2023.

The persistent presence of avian influenza raises concerns over its potential to mutate, spread and impact not only bird populations but also the poultry industry, which plays a significant role in the UK's economy.

Koi Herpesvirus Disease Resurfaces in 2023

Another troubling outbreak has reared its head in the form of Koi Herpesvirus (KHV) disease. A viral affliction with serious consequences for fish, particularly carp species, KHV has resurfaced in the UK, leading to notable mortalities.

The disease manifests through various symptoms, including necrotic patches on the gills, rough patches on the skin, sloughing mucous and sunken eyes – most apparent when water temperatures range between 16 to 28°C.

It's important to note that while KHV poses a significant threat to fish populations, it does not pose any risk to human health. The Fish Health Inspectorate (FHI) serves as the frontline in detecting and responding to KHV outbreaks. Should individuals suspect an outbreak, immediate communication with the FHI is vital, particularly when signs of KHV are observed or carp fatalities occur.

Formal monitoring programmes are swiftly initiated at KHV-affected sites, accompanied by thorough inspections by the FHI to ensure compliance with statutory controls. Once an outbreak is confirmed, the FHI enforces measures to contain and eliminate the disease, which may involve restricting the movement of aquatic animals, enhancing biosecurity measures, culling affected fish and implementing stringent cleaning and disinfection protocols.

Mitigating the Impact: Implementing Controls and Regulations

The FHI plays a pivotal role in controlling the spread of notifiable diseases. When a disease is confirmed, the FHI imposes controls aimed at containing the outbreak. These controls include restrictions on the movement of aquatic animals, the appropriate disposal of carcasses and notification of any re-occurrences or expansions of the disease's reach.

For KHV, specific designations are placed upon confirmation, limiting aquatic animal movement and requiring meticulous compliance with the FHI's regulations. The FHI must grant permission for any changes to designated areas, and site operators must adhere to strict protocols when moving live fish, fish eggs or gametes within or out of designated areas.

As the United Kingdom faces simultaneous outbreaks of COVID-19 variants, avian influenza and Koi Herpesvirus disease, effective containment strategies are essential to safeguard public health, animal welfare and economic stability.