Trends in total reports

There is a 5.4% increase (Figure 1 and Table 2) in the total reports of Acinetobacter spp. bacteraemia reported via the voluntary surveillance scheme in 2007 (1187 reports), compared to 2003 (1126 reports). This increase is lower than the 24% increase in reports for all bacteraemia (85,354 to 105,928) via the voluntary surveillance scheme during the same time period (provisional as of 8/Jan/2008). In comparison with data reported in 2006, there was a marginal increase (4.1%) in the number of reports of Acinetobacter spp. bacteraemia in 2007. The increase in reports of Acinetobacter spp. bacteraemia may be due to either increased incidence and/or increased ascertainment. Reports for 2007 are provisional as of 8 January, 2008 and the number of reported cases of bacteraemia may increase slightly due to late reporting.

Figure 1. Acinetobacter spp bacteraemia reports: 2003 to 2007

Completeness of laboratory reports

The number of laboratories voluntarily reporting data for Acinetobacter spp. bacteraemia has decreased marginally from 173 in 2003 to 162 in 2007 (Table 1). However, during this period there were increases in the percentage of laboratories either identifying Acinetobacter isolates to species level or reporting drug susceptibility data. The percentage of laboratories identifying Acinetobacter isolates to species level increased from 76% in 2003 to 88% in 2007 while the percentage reporting drug susceptibility data increased from 78% in 2003 to 91% in 2007. The percentage of laboratories identifying Acinetobacter species and reporting drug susceptibility data increased from 61% in 2003 to 79% in 2007.

It is important to note the majority of participating laboratories are relying on phenotypic identification systems which are less reliable than molecular methods; the latter are not available in most routine diagnostic laboratories. Data collection and analyses are further complicated by the fact reports of A. lwoffii may be due to contamination of blood cultures. In contrast with A. calcoaceticus/baumannii which, being frequently resistant to multiple antibiotics, is often associated with substantial patient morbidity, A. lwoffii is not usually pathogenic to humans with an estimated 20 to 25% of healthy individuals carrying this organism as part of normal skin flora. Participating laboratories are requested to report microbiology data for only clinically significant cases.

Table 1 Laboratories reporting Acinetobacter spp. bacteraemia: 2003 to 2007*

	2003	2004	2005	2006	2007
Number of reporting laboratories	173	166	171	172	162
Laboratories identifying to species level	76%	83%	81%	82%	88%
Laboratories reporting susceptibility data	78%	87%	84%	87%	91%
Laboratories identifying to species level and reporting susceptibility data	61%	71%	67%	71%	79%

* Data extracted 8 January 2008.

Last reviewed: 7 August 2009