Table 2 Clusters of dengue fever by all, indigenous and imported cases in Guangdong province, China, 2005-2010

With a maximum spatial cluster size of ≤50% of total population

1. all cases

M*

11

50.43

2006/8-2006/11

10,394,229

135.18

2688.65

<0.001

S†

1

0

2006/9-2006/10

862,662

429.69

886.44

<0.001

2. indigenous cases

M*

11

50.43

2006/8-2006/11

10,394,229

153.56

2760.44

<0.001

S†

1

0

2006/9-2006/10

862,662

471.25

902.08

<0.001

3. imported cases

M*

26

89.80

2008/4-2010/12

32,795,835

7.52

44.66

<0.001

With a maximum spatial cluster size of ≤10% of total population

1. all cases

same to that with a maximum spatial cluster size of ≤50% of total population

2. indigenous cases

same to that with a maximum spatial cluster size of ≤50% of total population

3. imported cases

M*

6

27.00

2008/4-2010/10

7,608,517

10.95

36.19

<0.001

S†

6

19.47

2007/4-2007/11

6,013,893

13.81

13.27

0.02

S†

3

39.40

2007/10

1,342,186

162.28

12.24

0.03