Table 2.

Comparison of S1 and N gene partial nucleotide sequences of IBV Italian isolates and reference strains

Strain	S1 gene nucleotide identity (%)
	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22
1. Italy-01	100	72.8	n/a	72.8	96.7	72.8	95.4	72.3	97.4	92.3	73.4	74	74.2	70.2	74.2	92.3	73.6	70	76.9	74.4	71.5	62.1
2. Italy-02	91	100	n/a	99.2	74.6	77.6	72.1	96.7	73.6	70	70.1	69.3	69.5	71.2	82.4	72.3	79.9	76.6	71.3	66.2	76.6	62.8
3. Italy-03	91.7	87	100	n/a	n/a	n/a	n/a	n/a	n/a	n/a	n/a	n/a	n/a	n/a	n/a	n/a	n/a	n/a	n/a	n/a	n/a	n/a
4. Italy-04	95	90	92.7	100	74.6	77.6	72.1	97.5	73.6	70.5	70.3	69.5	69.8	71.2	81.9	72.8	80.2	77.1	72.1	66.7	75.8	62.3
5. Italy-05	97.7	90.7	91.3	94	100	71.5	95.1	73.6	97.7	92.3	74.2	74.5	74.7	70.2	77	92.3	75.1	72.1	76.4	80	71.5	61.3
6. Italy-06	93.3	88.7	97.7	93.7	92.3	100	72.3	76.6	73.3	70.8	70.3	69.5	69.8	63.4	77.3	71.3	75	71.7	70.3	60.1	79	61.8
7. Italy-07	99.7	91.3	91.3	94.7	97.3	93	100	70.5	95.4	91.3	74	74	74.2	70.4	72.6	91.3	72.3	68.5	76.4	77.4	71.3	59.2
8. Italy-08	96.3	89.7	91	93	96	92	96	100	73.1	70	70.1	69.8	69.8	71.2	81.9	72.1	76.3	77.1	71.5	65.9	75.1	59.5
9. Italy-09	97.3	90.7	92.3	94	96	92.7	97	95	100	92.3	75.3	75	75.3	70.2	74.7	92.3	73.8	71.5	76.7	79.5	72.1	65.6
10. Italy-10	89.7	88.7	87	87.7	87.7	86.7	89.3	88	89.3	100	72.7	73.2	73.4	69.9	71.3	98.5	70.5	68.2	74.9	73.1	71	59.7
11. M41	89.7	86.7	89.3	90	88	90.3	90	89.7	90.3	87	100	96.9	96.6	89.5	74	73.2	70.1	71.9	78.4	76.6	73.7	66.9
12. H120	91.7	86.3	99.3	92.7	90.7	97.7	91.3	90.3	93	87	89.3	100	99.2	89.8	74	74	69	71.4	78.9	78.4	73.4	66.1
13. H52	90.3	88.3	90.3	91.7	89.3	90.7	90.7	90.3	91	87.3	95	89.7	100	89.5	74.2	74.2	69.3	71.6	78.6	78.1	73.7	66.4
14. Conn	94.7	89	93.3	94.3	93	93	95	92	96.7	89.3	93.7	94	94.3	100	71.8	70.7	66.9	64.5	73.9	71.8	72.3	65.9
15. D274	92.3	88.3	91.7	91.3	90.7	92	92.7	91.7	93	88.7	96.3	91.7	98	96.3	100	72.6	78	78.6	75.7	75.5	77.5	64.1
16. 4/91	89.3	88.7	87	87.7	88.3	86.7	89	87.3	89.3	99.3	86.3	87	87.3	89.3	88.7	100	70.8	71	75.4	73.8	71	61
17. Ark99	93	87.3	92.3	92.7	91.3	92	93.3	90.3	95	88.3	92	93	93.3	98.3	94.7	88.3	100	76.6	72.3	63	76.9	60
18. Gray	92.3	87	91.7	92	90.7	91.3	92.7	90	94.3	89.7	91.7	92.3	92.3	97.7	94.3	89.7	96.7	100	71.5	62.4	76.9	60
19. QXIBV	87.7	82.7	84	87	86.3	85.3	87.3	89	87.3	84	84.7	84.3	84.7	87.3	86.3	83.3	86.3	85.3	100	81	73.1	60.5
20. CK/CH/ LHB/96I	87.7	84.3	86.7	88.3	86	87.3	88	86.7	88.7	83.7	86	87.3	87	90	88.3	83.7	88.3	87.7	91	100	64.9	57.2
21. VicS	87	83.7	85.7	86.3	86.3	85.3	86.7	87	87	86.3	86	85	88.3	88	87.7	86.3	87.7	87.3	85	84.7	100	63.3
22. V18/91	61	61.3	61.7	61.9	60	61.3	60.7	61.7	61.3	61	61.3	62	63	61	63.7	60.7	60.3	61.7	66	64.7	66	100
N gene nucleotide identity (%)