WALES TB DASHBOARD QUARTER 2 2021

Figure 1: New Incidents in Q2 2021 and open Incidents as at the end of the quarter

CLICK ON REGIONS BELOW to explore in more detail

Live Herds*

New Incidents

Incidents closed

Open Incidents

Chan-ge**

Reactors Disclosed

Q1 2010 to Q2 2021

Wales 11,588 133 174 600 (-41) 2,421

High TB (West) 3,128 59 78 300 (-20) 1,398

High TB (East) 2,760 30 55 144 (-25) 270

Intermediate TB (Mid)

2,005 15 14 42 (+1) 196

Intermediate TB (North)

903 17 13 74 (+5) 426

Low TB 2,792 12 14 40 (-2) 131

Sparklines show open cases, adjusted by herd numbers, on a quarterly basis since 2010. Red bar indicates highest level, green bar lowest. * Live herds at end of previous year (2020). **Change in the number of open incidents since last quarter in brackets.

Lowest TB levels in North West Wales,

highest in South West

Most TB breakdowns in Wales are in the

high TB areas in the East and West

WALES BACK

The yearly rolling average of open incidents began to decline in 2012. Since 2014 there has been small increase and decreases between quarters. In Q2 2021, open incidents decreased by 6% compared to the previous quarter.

New, closed and open incidents

Incidence, prevalence and animal-level risk

Recurrence – how many closed incidents break down again?

Overall fall in incidence (blue line) since 2012, despite fluctuations. The incidence in Q1 2020 is the lowest recorded in the time series. During 2020, there were 5.7 new breakdowns per 100 OTF tests, which is the lowest annual incidence in 16 years. Prevalence (green line) decreased between Q2 2012 and Q3 2014 but has increased slightly since, with some fluctuations.

Top chart shows incidents closed from Q1 2010 to Q2 2019. Blue line shows incidents that remained clear over subsequent 2 years, red line represents recurrence. Green line in bottom chart expresses recurrence as a percentage. 32% of incidents closed in Q2 2019 entailed a recurrence in the subsequent 2 years. The annual 2-year recurrence rate of incidents closed in 2018 was 32%.

HIGH TB AREA – WEST (WEST)

BACK

Incidence levels have been broadly steady between 2014 and 2018, with seasonal fluctuations. There was a large decrease in incidence in Quarter 4 2019, which is the lowest ever recorded in the area in any quarter since 2009. Incidence during 2020 and continuing into 2021 has remained steady and we have not seen the usual seasonal peaks compared to other years. Herd prevalence was on the decline between the middle of 2019 to the middle of 2020 before a small increase. There was a decrease in the latest quarter and is 16% lower compared to a peak we saw in Q3 2019.

Q2 2021 summary

New, closed and open incidents

Incidence, prevalence and animal-level risk

Live

Herds New

Incidents Incidents

Closed Open

Incidents Reactors

Disclosed Q1 2010

to Q2 2021

High TB (West) 3,128 59 78 300 (-20) 1,398

There was a sharp fall in open incidents in 2013, relatively steady thereafter with some fluctuations. There has been a fall in the one year rolling average during 2020.

HIGH TB AREA – EAST (EAST)

BACK

There has been a downward trend in herd prevalence between 2017 Q4 and the latest quarter. Prevalence in Q2 2021 is the lowest in the 12-year supervisory period.

There was a spike in incidence in Q3 2017 followed by decrease with some fluctuations. Quarter 2 2021, is the lowest level of incidence in the time series.

The spike in reactors per 1,000 animals tested in 2020 Q4 coincides with a number of breakdowns with a large number of reactors identified along with an increase in animal targeted testing, e.g. gamma testing rather than an increase in surveillance testing. This has since decreased to the level in the 12-year supervisory period in Q2 2021.

The number of open incidents has been on the decline since 2017. The rate of the decreases has steadied over the last four quarters.

Q2 2021 summary

Live

Herds New

Incidents Incidents

Closed Open

Incidents Reactors

Disclosed Q1 2010

to Q2 2021

High TB (East) 2,760 30 55 144 (-25) 270

New, closed and open incidents

Incidence, prevalence and animal-level risk

INTERMEDIATE TB AREA – MID (MID)

BACK

Incidence broadly stable over the last few years with some fluctuations. Herd prevalence has remained broadly stable over the long term with 2.1 TB restricted herds per 100 herds in Quarter 2 2021. There has been an increase in the number of reactors per 1,000 animals tested over the last year following a downward trend in the previous five quarters since Q1 2019.

There was a sharp increase in open incidents in Q1 2019. The 1-year rolling average of open incidents increased between Q3 2018 and Q4 2019, however this has since declined and levelled out in the latest quarter.

Q2 2021 summary

Live

Herds New

Incidents Incidents

Closed Open

Incidents Reactors

Disclosed Q1 2010

to Q2 2021

Intermediate TB (Mid) 2,005 15 14 42 (+1) 196

New, closed and open incidents

Incidence, prevalence and animal-level risk

INTERMEDIATE TB AREA – NORTH (NORTH)

BACK

There has been an upward trend in prevalence since Q4 2017 with the rate of increasing rising since Q3 2020. At the end of Q2 2021, 8.2% of herds are restricted. This is the highest in the time series and is currently higher than the High East TB Area.

There was a sharp increase in incidence in the last two quarters of 2020 but has fallen in the first two quarters of 2021. Over the long-term there has been a degree of fluctuation in incidence in this area. These increases are driven by a cluster of breakdowns near the border with England.

There was a sharp increase in open incidents in 2017 with the 1-year rolling average of open incidents levelling out in recent quarters but still increasing. There were 74 open incidents at the end of Q2 2021, which is the highest in the time series. However, the difference in new incidents and closed incidents has narrowed in Q2 2021 since we saw the highest number of new incidents in Q1 2021.

Q2 2021 summary

Live

Herds New

Incidents Incidents

Closed Open

Incidents Reactors

Disclosed Q1 2010

to Q2 2021

Intermediate TB (North) 903 17 13 74 (+5) 426

New, closed and open incidents

Incidence, prevalence and animal-level risk

LOW TB AREA BACK

New and open incidents have increased since the beginning of 2020. There were 23 new incidents during Q1 2021, which is the second highest in the series. This is driven in part to a cluster of incidents in the Denbigh and Conwy area. There were 40 open incidents at the end of Q2 2021, which is second highest in the series. However, these numbers are very low compared to the other TB Areas in Wales with 98.6% of herds TB Free in this area.

In Q3 2020, there was the highest number of new incidents per 100 tests since Q2 2012. This has since fallen but is higher compared to the last few years. Incidence, prevalence and animal risk consistently the lowest in Wales.

Q2 2021 summary

Live

Herds New

Incidents Incidents

Closed Open

Incidents Reactors

Disclosed Q1 2010

to Q2 2021

Low TB 2,792 12 14 40 (-2) 131

New, closed and open incidents

Incidence, prevalence and animal-level risk

BACK