Epidemiology and Infection Control Implications of Acinetobacter spp. in Hong Kong

Abstract

In a previous study, we showed that Acinetobacter genomic DNA group 3 was the most common species among blood culture isolates and was commonly found on superficial carriage sites of the healthy and the sick, which are different findings from those reported in Europe and North America. We used amplified ribosomal DNA restriction analysis and pulsed-field gel electrophoresis to study further the molecular epidemiology of acinetobacters in our region. Over a study period of 6 weeks with 136 consecutive routine clinical isolates (1.33% of all specimens), genomic DNA groups 2 (Acinetobacter baumannii), 3, and 13TU were obtained from 59 of 69 positive patients. There is a significant difference in the specimen sources of the three genomic DNA groups, with group 13TU being significantly associated with the respiratory tract (chi-square exact test, P ‫؍‬ 0.0064). Settle plates showed a significantly heavier environmental load from the intensive care unit (ICU) than from the four surgical wards examined (22 of 70 versus 76 of 120 plates with <5 colonies; chi-square test, P < 0.0001). Genomic group 3 accounted for 6 of 12 clusters of possibly related strains among patients, between patients and the ICU environment, and in the ICU environment. Genomic groups 2 and 3 accounted for 21% of the 132 genomically identified isolates recovered from 21 of 41 local vegetables, 53 of 74 fish and meat samples, and 22 of 60 soil samples. Group 13TU was present only in patients' immediate surroundings. The role played by the environment and by human carriage should be evaluated in order to devise a cost-effective infection control program pertinent to our situation of acinetobacter endemicity.

Acinetobacter baumannii : Emergence of a Successful Pathogen

“…Interestingly, A. baumannii and Acinetobacter genomic species 11 (each at 27%) were the predominant species, followed by A. calcoaceticus and Acinetobacter genomic species 3 (each at 13%), while Acinetobacter genomic species 13 was found only once. In Hong Kong, 51% of local vegetables were culture positive for Acinetobacter species, the majority of which were Acinetobacter genomic species 3 (75%), but one sample grew A. baumannii (245). Houang et al found acinetobacters in 22 of 60 soil samples in Hong Kong, and the most frequent species were Acinetobacter genomic species 3 (27%) and A. baumannii (23%), with only one sample yielding A. calcoaceticus (245).…”

Multidrug resistant Acinetobacter baumannii--the role of AdeABC (RND family) efflux pump in resistance to antibiotics.

“…Among members of the genus Acinetobacter baumannii species is most frequently isolated from humans [12,113,125]. These organisms are widely distributed in nature and may be present in soil, water and sewage, also are found in variety of foodstuffs [39,113,124].…”

Identification of Acinetobacter Species and Genotyping of Acinetobacter baumannii by Multilocus PCR and Mass Spectrometry

“…However, these MLST approaches cannot provide a real-time surveillance capability. Furthermore, Acinetobacter infections can be the result of one of several pathogenic Acinetobacter species, including A. baumannii, Acinetobacter genomospecies 13TU, or Acinetobacter genomospecies 3 (17,35,42,45).…”