Table 3

Table 3
Real-time PCR amplification of Coxiella burnetii from environmental samples collected inside a cave, Bizkaia, Spain, March 2021–Feb 2023 (n = 122 samples)
Sample type and sampling site^a	Cq values^b
Sample type and sampling site^a	4 Mar 2021	22 Mar 2021	18 May 2021	2 Aug 2021	2 Nov 2021	28 Feb 2022	9 May 2022	22 Sep 2022	19 Dec 2022	2 Feb 2023
Faeces
Main entrance (F1)	31.3	ND	ND	ND	ND	ND	ND	ND	ND	ND
Main entrance (F2)	35.7
Main entrance (F3)	34.3
Fence (F4)	32.3
Interior (F5)	Und.
Alternative entrance (F6)	Und.
Dust^c
Main entrance (D1)	31.1	ND	34.6	36.9	35.1	34.7	Und.	35.5	36.6	ND
Main entrance (D2)	31.3		31.3	26.9	31.8	27,0	Und.	32.1	35.9
Fence (D3)	28.7		25.6	24.9	28.6	22.5	29.1	27.7	30.0
Interior 1 (D4)	31.9		33.6	34.2	35.8	34.2	34.3	34.6	Und.
Interior 2 (D5)	32.5		35.4	36.7	Und.	33.3	34.6	Und.	Und.
Interior 3 (D6)	Und.		33.7	Und.	36.1	Und.	37.3	Und.	Und.
Interior 4 (D7)	Und.		34.2	Und.	Und.	35.1	36.1	36.8	Und.
Interior 5 (D8)	Und.		Und.	Und.	Und.	34.4	34.6	Und.	Und.
Alternative entrance (D9)	35.4		Und.	Und.	Und.	35.9	34.9	Und.	Und.
Alternative entrance (D10)	Und.		35.0	Und.	Und.	Und.	Und.	Und.	Und.
Aerosols
Aerosol 1 (A1)	Und.	32.2	Und.	33.4	Und.	Und.	ND	36.3	35.7	Und
Aerosol 2 (A2)	35.4	24.6	26.0	Und.	27.8	29.2		25.3	24.9	25.9
Aerosol 3 (A3)	Und.	Und.	36.3	Und.	Und.	Und.		33.3	36.8	29.6
Aerosol 4 (A4)	33.2	Und.	Und.	Und.	Und.	Und.		36.4	Und.	Und.
Wind direction at sampling^d	South-East	North	South-West	North	South-West	South-East	North-East	North	South-East	North-West
Cq: quantification cycle; ND: not done; Und.: undetermined (negative). ^a See Figure 1 for location of sampling sites inside the cave. ^b Cq interpretation as follows: Cq < 35: positive; Cq > 35 and ≤ 40: weakly positive; Cq > 40: negative. The lowest Cq value (higher bacterial load) obtained in dust during each sampling session is marked in bold. PCR target was the transposon-like repetitive region IS1111. ^c On 22 March 2021 and 2 February 2023, dust samples were taken only for viability studies. ^d Data were provided by the Basque Agency of Meteorology (Euskalmet, https://www.euskalmet.euskadi.eus/inicio) and collected at a meteorological station located 6.8 km from the cave.