To date, only one animal disease, rinderpest, has been eradicated from the face of the earth. So what can the battle against the virus tell us about future disease eradication?
In June 2011, rinderpest, one of most deadly and contagious cattle diseases in history, was declared eradicated by the World Organisation for Animal Health (OIE).
In addition to its high mortality rate, rinderpest had severe repercussions for human populations, causing large-scale famines, mass poverty and the destruction of global agricultural industries.
Apart from a small amount of laboratory stocks, the virus is now considered an infection of the past and strategies to make further progress in disease eradication are underway.
Disease control programmes are largely established with complete eradication as the ultimate aim. There can be number of reasons why this is not always a feasible target and therefore reducing the health and economic impact of a disease is the focus.
In 1994, the Global Rinderpest Eradication Programme was initiated. Endorsed by the OIE, the Food and Agriculture Organisation and the Institute for Animal Health, it was hugely successful in gradually reducing outbreaks.
The OIE claims it is currently working on strategies to make progress in the international control of other major diseases, such as foot-and-mouth, rabies, and peste des petits ruminants (PPR).
In 2001, as foot-and-mouth cascaded through farms and fields, the UK learned the hard way about the importance of being on alert for potential infection at all times.
Having an effective contingency plan in place is the main way of preventing the spread of contagious disease.
Dr Michael Baron, honorary fellow at The Pirbright Institute, is currently developing control strategies for the rinderpest relative, PPR, also known as goat or sheep plague.
The disease is now commonplace in Africa, the Middle East and parts of India and China. It can cause mortality rates of up to 90 per cent and current vaccination attempts are proving ineffective.
Dr Baron says: “The prevalence of PPR is a moving target as it keeps spreading. It is not a major issue for UK farmers, due to the extensive veterinary services and regulated movement controls we have.
“However, finding a solution will help us move closer to curing other diseases which are a threat to the first world.”
He says in the long-term, mass vaccination alone is impractical as a method of disease eradication.
“We need to know more about patterns of animal breeding and movement in at-risk countries, and we need to involve livestock keepers themselves in disease control. This way, vaccination can be applied in the most effective manner and producers can adapt practices to limit the spread of disease.
“Perhaps the biggest threat to UK farming on the disease front is Brexit. Much of the funding for disease work has come from the EU.
“Five years from now, we may find ourselves short on expertise to deal with the next virus to land here.”
- Bovine Tuberculosis (TB) – In 2016, selected areas of Britain have been subject to a badger cull, as an attempt to reduce the spread of TB amongst cattle. The UK is now split into risk areas, designed to implement suitable control strategies.
- Foot and Mouth Disease (FMD) – the last case of FMD recorded in the UK was in 2007, following the national outbreak of 2001. The spread was quashed and has not resurfaced, but did aid a rethink in terms of tightening disease controls.
- Avian Influenza (bird flu) – mainly a disease seen in live birds, the virus can also be caught by humans who come into contact with an infected animal. Several cases of varying severity have been detected in UK poultry flocks, since the first one in April 2006. The most recent was small outbreak in January 2016 in Dunfermline, Scotland.
- African Swine Fever – the disease is slowly moving across Europe and is one of the more prominent threats to UK pig farms. It is yet to be seen in the UK but is a concern due to its highly contagious nature.