Type and sensitivity of the detection method |
Type of test |
The diagnostic test used for the detection of EM must be defined. Modifications of the original method should be indicated. |
Yes |
Yes |
NA |
Test sensitivity |
The sensitivity and specificity of the test used in the surveillance system must be reported. This would ideally be estimates from each participating laboratory reported as a point estimate (average) of the values across the country with minimum and maximum values or a probability distribution. Alternatively, a value of 0.78, as recommended by EFSA 2015, shall be used. |
Yes |
Impossible to evaluate |
The evidence provided to support the test sensitivity value for the SCT (Eckert, 2003) actually refers to a previous work (Hofer et al., 2000) which focusses on the prevalence in the target population and not in the sensitivity of the SCT. The almost perfect sensitivity of the SCT (0.99) is actually an assumption. A safer option would be to follow the EFSA recommendation (Test Se = 0.78). As an alternative, NI should provide evidence to support the suggested test sensitivity value of 0.99. |
Selection of the target population |
Definition of susceptible host population targeted by the system |
The susceptible wild definitive host population(s) targeted by the surveillance system should be described and the choice justified. If domestic host species are sampled, evidence for the absence of wild definitive hosts and for these domestic animals having had access to outdoors should be provided. |
Yes |
Yes |
NA |
Size of susceptible host population targeted by the system |
The size of the targeted (wildlife) population should be reported, together with the evidence for this. Historical population data should be updated since these may not reflect current populations. |
Yes |
Yes |
NA |
Sampling strategy |
Epidemiological unit |
It should be clearly defined if individual animals or individual faeces samples collected from the environment constitute the epidemiological unit. If individual faeces samples are collected from the environment, the method applied to establish the species from which the faeces originated has to be reported. |
Yes |
Yes |
NA |
Sample size calculation |
The applied survey design should be fully documented, including considerations regarding potential biases inherent in the survey design. The method and the formula used to calculate the sample size should be fully documented. |
Yes |
Impossible to evaluate |
The use of a test sensitivity (0.99) not supported by adequate scientific evidence makes impossible to evaluate the adequacy of the output from the RiBESS tool |
Implementation of the sampling activity |
The sampling methods used should be fully documented including the related assumptions and uncertainties, and a justification for choosing the approach should be provided. Time frame of the surveillance data and geographical clustering of the infection must to be reported. The sample collection period must comprise the whole year and the spatial distribution of the sampling must be homogeneous. |
Yes |
Yes |
NA |
Methodology |
Design Prevalence (DP) |
DP is specified in Annex II to Regulation (EU) No 1152/2011 and must be 1% or lower. |
Yes |
Yes |
NA |
Geographical epidemiologic unit |
The geographic epidemiological unit(s) identified as target for the surveillance activity has to be clearly indicated and supported by justification. |
Yes |
Yes |
NI was correctly considered as one epidemiological unit in the analysis. |
Methodology for calculation of area sensitivity |
For the calculation of the area sensitivity, the diagnostic sensitivity should be set conservatively to the lowest value, excluding the lowest 20th percentile, from the ones reported in the scientific literature and related to the diagnostic tests implemented by the countries listed in Annex I of the Commission Delegated Regulation (EU) No 1152/2011. In this case, is 78% (EFSA AHAW Panel, 2015). |
Yes |
Impossible to evaluate |
Not even assuming the test sensitivity value proposed by NI (0.99) the area sensitivity achieved satisfies the legal requirements (0.806).
Note: the absence of scientific evidence does not imply that the proposed test sensitivity (0.99) is wrong. EFSA, however, in the absence of adequate scientific evidence cannot assess the performance of the surveillance activity. |