Yorkshire duck farm bird flu outbreak: How is the disease transmitted and can it affect humans?

A case of bird flu has been confirmed at a duck breeding farm in East Yorkshire. 

 

The Department for Environment, Food and Rural Affairs (Defra) said it occurred in the village of Nafferton, and that an exclusion zone had been set up around the farm to prevent further transmission. It added that 6,000 ducks would be culled. 

 

"We are taking immediate and robust action which includes introducing a restriction zone and culling all poultry on the farm to prevent any potential spread of infection. A detailed investigation is ongoing,” a spokeswoman told the BBC.

 

"We have a strong track record of controlling and eliminating previous outbreaks of avian flu in the UK."     

 

The last time a case of bird flu occurred in the UK was in 2008, when chickens on a farm in Banbury, Oxfordshire tested positive for the virus.  

RISK TO HUMANS

 

Bird flu is mainly spread between birds, but under some circumstances humans can also catch the virus.

 

This happens when people come into close contact with infected birds or bird droppings, such as when cleaning or plucking infected birds or entering contaminated water.

 

But transmission to humans is extremely rare, and according to the World Health Organisation less than 500 people have died from the disease in previous outbreaks across the world. 

 

There are two strains – H5N1 and H7N9 – that have a particularly high mortality rate in humans and have resulted in serious concern in recent years, and Public Health England has already confirmed the case in Yorkshire was caused by neither of these strains. 

 

"Based on what we know about this specific strain of avian influenza, the risk to human health in this case is considered extremely low,” a spokesman said. The exact identity of the strain responsible is expected to be revealed at some point this week, but it is unlikely to be one that poses a significant threat to human safety. 

 

On its website, the NHS says most strains of bird flu are not dangerous to humans:  "There are many types of bird flu, most of which are harmless to humans. However, two types have caused serious concern in recent years. These are the H5N1 and H7N9 viruses.

 

"Although these viruses don't infect people easily and are usually not transmitted from human to human, several people have been infected around the world, leading to a number of deaths.

 

"Other bird flu viruses (particularly H7N7 and H9N2) have also infected people, but these have rarely caused severe illness."