Bovine TB is spreading. The prevalence of all regions classified as high risk area is 2017 at 12.8 percent. The prevalence of all edge areas is at 5.3 percent. In 1996 the prevalence of the areas belonging now to high risk and edge area was under 1%. Because of higher prevalence in certain areas they joined then high risk areas and edge areas. In areas within this categories now the prevalence and risk was raising constantly from 1996 until 2017. Any stricter regulations compared to low risk areas, like testing in shorter intervals (12 M, 6M or Premovement-tests), did not show an desirable effect.
In the southwest as an example vor highrisk areas and the midlands as an example for highrisk and edge areas the prevalence did raise constantly from 1996 to 2017.
This graph is also based on the history of the current three risk areas high, edge and low.
In this case however the number of farms have been grouped by prevalence “<1%,” “1% to 5% “and “> 5% “ The number of farms within the concerning group within a year is calculated and put in relation to the whole number of farms within this year. In 1996 for example the prevalence of all farms (belonging to high, edge and low in 2017) was under 1%. In 1996 100% of the farms are within the group: “< 1%”.
This is changing the following year. On from 1997 to 2004 the percentage of farms in group <1% is about 60%. On from 2004 until 2017 the percentage of farms in group <1% is drops to 40%. The figures show, that the problems of growing prevalence already start in 1997. From 1997 until 2004 the percentage of 1% to 5% is 40%. 2005 the “>1% part” is splitting to 20% “ >1% to 5% and about 60 percent to “> 5%.” In 2017 the whole” > 1% fraction” is within the “>5%.”
Starting in the second half of the 90ies farms many farms are moving to categories of high risks areas and higher prevalence fraction. Bovine TB in England is spreading since 1997 and not under control at all.