A solution to the badger cull? UK scientists develop a tuberculosis vaccine for cows that could help stop the spread of the deadly disease among cattle
- The new vaccination is a variant of the BCG vaccine given to humans against TB
- It was created by the University of Surrey by removing a proteins from BCG
- This prevents a cows recording a false positive for TB when given a skin test
- It’s hoped a new vaccine will help stop badger culls as it limits the spread of TB
A new vaccine that could stop the spread of tuberculosis in cattle is offering wildlife groups hope that it could see the end of badger culls.
Researchers from the University of Surrey have created a strain of the BCG vaccine that they say prevents the spread of TB and is compatible with a compulsory skin test that is designed to determine whether a cow has the disease or not.
This will please animal welfare groups who have called for the development of a compatible vaccine as a way to stop the need for badger culls.
‘This BCG Vaccine could be a major break through in bringing an end to the cruel costly and ineffective badger cull’, says Dominic Dyer, CEO of the Badger Trust.
A new vaccine that could stop the spread of tuberculosis in cattle is offering wildlife groups hope that it could see the end of badger culls (stock image)
The BCG vaccine given to humans CAN be used on cattle but if a skin test is taken of a vaccinated cow it will show as having TB and farmers will be required to kill it.
This is due to the fact it is currently impossible to tell BCG vaccinated cows from infected cows using the skin test.
An outbreak, or even a suspected outbeak of TB in a cow can result in the whole herd having to be slaughtered, costing farmers millions of pounds per year.
‘By being able to differentiate between a cow vaccinated against TB & a cow that carries the disease, the Government will be able to introduce a large scale cattle vaccination programme across England.
‘This combined with badger vaccination improved TB testing for cattle & tighter biosecurity and movement controls, will bring about a significant reduction in bovine TB without the mass slaughter of badgers’, Mr Dyer said.
The new vaccine, developed by the University of Surrey, takes out the proteins in the BCG vaccine that triggers a ‘positive’ reaction in the skin test while keeping the protection against the disease that BCG offers.
In September Ellie Brodie, senior policy manager at The Wildlife Trusts, said: ‘Evidence shows that badgers are not the primary cause of the spread of TB in cattle.
‘The primary route of infection is from cow-to-cow contact – so a vaccine for cattle should be a government priority.’
Wildlife campaigners have called for an end to the UK badger cull, calling on the government to invest in the creation of a vaccine instead
England’s controversial badger cull was introduced in 2013 and is now being enacted in 40 areas in an attempt to reduce transmission to cattle.
WHAT IS BOVINE TB?
Bovine tuberculosis is a disease of cattle that can also infect badgers, deer, goats, pigs, dogs and cats.
The disease is caused by the bacteria Mycobacterium bovis.
This is related to the microbe that causes tuberculosis in humans.
Bovine tuberculosis is typically transmitted aerially through coughs and sneezes.
It causes fever, coughing, weight loss, pain, diarrhoea and ultimately death.
Badgers are the most significant wildlife reservoir for the bacterium.
In the United Kingdom, most bovine tuberculosis outbreaks occur in the South West and the West Midlands.
“In order to control the spread of bovine TB, effective vaccination and accurate early diagnosis are critical’, said Johnjoe McFadden, from the University of Surrey.
‘This new vaccine provides protection against bovine TB and will help in the fight against this deadly disease which infects over 50 million cattle worldwide and is economically devastating to farmers.’
Researchers tested the new vaccine on guinea pigs and found that TB infected guinea pigs tested positive for the disease using the skin test whilst guinea pigs vaccinated with the new drug did not.
This potentially allows farmers and veterinarians to protect their animals with the new BCG vaccine, whilst still maintaining a diagnostic test that will detect TB.
Professor McFadden said they now need to demonstrate that the skin test and vaccine work in cattle.
‘If they do, then it will be possible to vaccinate cattle against TB yet retain the value of skin test for diagnosis.’
The findings have been published in the journal Scientific Reports.
WHAT IS TUBERCULOSIS AND IS IT MAKING A COMEBACK IN BRITAIN?
Tuberculosis (TB) is a bacterial infection spread between people by coughing and sneezing.
The infection usually affects the lungs but the bacteria can cause problems in any part of the body, including the abdomen, glands, bones and the nervous system.
At the beginning of the 19th century, TB killed at least one in seven people in England. But today – thanks to improvements in health, faster diagnoses and effective antibiotics – less than six per cent of those with TB are killed by the disease, with just under 4,672 cases reported in the UK in 2018.
Despite these improvements, in 2010 a report into TB in London and Britain as a whole found that the number of cases in the capital had risen by almost 50 per cent from 1999.
Professor Alimuddin Zumla of University College London attributed the rise to people living under ‘Victorian’ conditions, with poor housing, inadequate ventilation and overcrowding in certain deprived areas of London.
He also said the increase in TB cases was predominantly among people born outside Britain, but who appear to have been infected in the UK, rather than in their country of origin.
The infection usually affects the lungs but the bacteria can cause problems in any part of the body, including the abdomen, glands, bones and the nervous system
TB infection causes symptoms like fever, coughing, night sweats, weight loss, tiredness and fatigue, a loss of appetite and swellings in the neck.
If the immune system fails to contain TB bacteria the infection can take weeks or months to take hold and produce symptoms, and if it is left untreated it can be fatal.
TB is most common in less developed countries in sub-saharan and west Africa, southeast Asia, Russia, China and South America.
Researchers in Wales said that of those infected with this disease in 2017, 55 per cent were born outside the UK.
Although, 20 per cent had at least one of the following social risk factors:
- Being in prison
- IV drug use
- Poor housing or homelessness