Performance of the point-of-care circulating cathodic antigen test in the diagnosis of schistosomiasis japonica in a human cohort from Northern Samar, the Philippines

Table 2 Positivity rates and prevalences determined by different diagnostic tests across the different groups stratified by parasite burden and in the entire cohort

Diagnostic test	KK (+) Moderate	KK (+) Light^§				KK (−)		Entire cohort
	(EPG: 100–399)	(EPG: 10–99)		(EPG: 1–9)		(EPG: 0)		(EPG: 0–399)
	Positive, % (n/n)	Positive, % (n/n)	P*	Positive, % (n/n)	P*	Positive, % (n/n)	P*	Prevalence, % (n/n)	P*
POC-CCA^†	100 (4/4)	57.7 (15/26)		16.7 (13/78)		6.3 (19/304)		12.4 (51/412)
F_ddPCR	100 (4/4)	100 (26/26)	0.0026	97.4 (76/78)	< 0.0001	66.1 (201/304)	< 0.0001	74.5 (307/412)	< 0.0001
SR_ddPCR	100 (4/4)	100 (26/26)	0.0026	92.3 (72/78)	< 0.0001	57.6 (175/304)	< 0.0001	67.2 (277/412)	< 0.0001
U_ddPCR	100 (4/4)	88.5 (23/26)	0.0269	47.4 (37/78)	0.0004	43.4 (132/304)	< 0.0001	47.6 (196/412)	< 0.0001
SL_ddPCR	100 (4/4)	76.9 (20/26)	>0.05	23.1 (18/78)	>0.05	20.4 (62/304)	< 0.0001	25.5 (105/412)	< 0.0001
Sj23-LHD-ELISA^#	100 (4/4)	53.8 (14/26)	>0.05	61.5 (48/78)	< 0.0001	18.1 (55/304)	< 0.0001	30.6 (126/412)	< 0.0001
SjSAP4-ELISA^#	100 (4/4)	92.3 (24/26)	0.0159	91.0 (71/78)	< 0.0001	56.3 (171/304)	< 0.0001	65.5 (270/412)	< 0.0001

^{ddPCR Droplet digital PCR; The ddPCRs performed on faeces, serum, urine and saliva were designated as F_ddPCR, SR_ddPCR, U_ddPCR and SL_ddPCR, respectively. ELISA Enzyme-linked immunosorbent assay, EPG Eggs per gram of faeces, KK Kato-Katz; POC-CCA Point-of-care circulating cathodic antigen}
^§Individuals with a light infection were categorised into two subgroups with EPG of 10–99 and 1–9
*P values were determined by McNemar's test
^†R cut-off value: 0.1344
^#Cut-off values for ELISA assays: Sj23-LHD-ELISA, 0.2185; SjSAP4-ELISA, 0.1832 [25]

ISSN: 2049-9957