Table 4 Occurrence and prevalence of class 2, 3, and 4 integrons in Gram-positive and Gram-negative bacteria

Class 2 integrons

 Escherichia coli

7.4 % (31/417); dfrA1-sat2-aadA1 (77.4 %, 24/31), estX-sat2-aadA1 (19.4 %, 6/31) and estX-sat2-△aadA1 (3.2 %, 1/31)

BfT-GermVet monitoring study, Germany, 2004–2006

[67]

 Enterobacteriaceae

34.9 % (52/149); II2 (Tn7), III2 (estX-sat2-aadA1-orfX, most widely distributed) and IV2 (aadA1, first reported)

E. coli amd K. pneumoniae strains from swine and chickens, Portugal

[62]

 E.coli

3.0 % (3/100)

Spain

[65]

 E. coli

3.6 % (4/111); dfrA1-sat1-aadA1

Preliminary study, Guangzhou, China

[68]

 E. coli

One out of 322

Irrigation water and associated sediments, El Paso, Presidio and Weslaco

[69]

 Coliforms

2.7 % (5/183)

Rivers in northern region of Turkey

[63]

 Pseudomona aeruginosa

19.5 % (23/118); dfrA1-sat1-aadA1, first report of class 2 integron in this species of bacteria

Preliminary study, Guangzhou, China

[19]

 Shigella flexneri

100 % (58/58); dfrA1-sat1-aadA1

Stool samples of sporadic diarrheic patients, China, 2005–2006

[70]

 S. sonneii

93 % (2/43)

Adult patients with diarrhoea, Senegal

[71]

 S. enterica

85 contemporary multi-drug resistant D-Tartrate-Positive isolates; dfrA1-sat1-aadA1

S. enterica Serovar Paratyphi B isolates Germany, 1995–2001

[72]

 S. enteritidis

4.3 %; estX-sat2-aadA1

Poultry samples, Japan

[33]

 E. faecalis

Two strains harboring Class 1 and 2 integrons; dfrA1-sat1-aadA1, first evidence of class 2 integron in G⁺ bacteria

Preliminary study, Guangzhou, China

[52]

Class 3 integrons

 E.coli

Australia

[73]

 E.coli

ges1/oxa10:aac(6′)

Switzerland

[74]

 Serratia marcescens

imp1/aacA4

Japan

[75]

 Klebsiella pneumoniae

ges1/oxa10:aacA4

The urine of an intensive care unit patient in Portugal

[76]

Class 4 integrons

 Vibrio cholerae

Collection de I’Institut Pasteur (CIP)

[77, 78]

 V. metschnikovii

[77]