Detection and Quantification of Total and Pathogenic Vibrio parahaemolyticus in Anadara subcrenata in the Zhoushan Archipelago

Table 3

Contamination levels of total Vibrio parahaemolyticus in Anadara subcrenata in different seasons.

Seasons	Number of samples	No. of positive samples	Positive rate (%)	Percentage of samples with total V. parahaemolyticus (MPN/g)					Densities of tlh positive samples (MPN/g)
				None detected (%)	<10 (%)	10–10^2 (%)	10^2–10^3 (%)	>10^3 (%)	Median	Min–max
Spring	75	56	74.67	25.33	28.00	34.67	4.00	8.00	20.00	0.36–2400
Summer	99	98	98.99	1.01	1.01	35.35	28.28	34.34	210.00	7.40–2400
Autumn	78	69	88.46	11.54	10.26	44.87	14.10	19.23	43.00	0.61–2400
Winter	64	42	65.63	34.38	64.06	1.56	0.00	0.00	0.92	0.30–15
Total	316	265	83.86	16.14	22.47	30.70	13.29	17.41	42.00^#	0.30–2400

The positive rate of four seasons was in significant difference (χ² = 38.371, df = 3, ). ^#The contamination level of total V. parahaemolyticus of four seasons was in significant difference (χ² = 122.797, df = 3, ).