Mailed versus frozen transport of nasal swabs for surveillance of respiratory bacteria in remote Indigenous communities in Australia

O’Grady, Kerry-Ann F , Whiley, David M, Torzillo, Paul J , Sloots, Theo P, & Lambert, Stephen B (2013) Mailed versus frozen transport of nasal swabs for surveillance of respiratory bacteria in remote Indigenous communities in Australia. BMC Infectious Diseases, 13(543).

View at publisher



Surveillance programs and research for acute respiratory infections in remote Australian communities are complicated by difficulties in the storage and transport of frozen samples to urban laboratories for testing. This study assessed the sensitivity of a simple method for transporting nasal swabs from a remote setting for bacterial polymerase chain reaction (PCR) testing.


We sampled every individual who presented to a remote community clinic over a three week period in August at a time of low influenza and no respiratory syncytial virus activity. Two anterior nasal swabs were collected from each participant. The left nare specimen was mailed to the laboratory via routine postal services. The right nare specimen was transported frozen. Testing for six bacterial species was undertaken using real-time PCR.


One hundred and forty participants were enrolled who contributed 150 study visits and paired specimens for testing. Respiratory illnesses accounted for 10% of the reasons for presentation. Bacteria were identified in 117 (78%) presentations for 110 (79.4%) individuals; Streptococcus pneumoniae and Haemophilus influenzae were the most common (each identified in 58% of episodes). The overall sensitivity for any bacterium detected in mailed specimens was 82.2% (95% CI 73.6, 88.1) compared to 94.8% (95% CI 89.4, 98.1) for frozen specimens. The sensitivity of the two methods varied by species identified.


The mailing of unfrozen nasal specimens from remote communities appears to influence the utility of the specimen for bacterial studies, with a loss in sensitivity for the detection of any species overall. Further studies are needed to confirm our finding and to investigate the possible mechanisms of effect.

Clinical trial registration

Australia and New Zealand Clinical Trials Registry Number: ACTRN12609001006235.

Keywords: Respiratory bacteria; RT-PCR; Specimen transport; Laboratory methods

Impact and interest:

0 citations in Scopus
Search Google Scholar™
1 citations in Web of Science®

Citation counts are sourced monthly from Scopus and Web of Science® citation databases.

These databases contain citations from different subsets of available publications and different time periods and thus the citation count from each is usually different. Some works are not in either database and no count is displayed. Scopus includes citations from articles published in 1996 onwards, and Web of Science® generally from 1980 onwards.

Citations counts from the Google Scholar™ indexing service can be viewed at the linked Google Scholar™ search.

Full-text downloads:

59 since deposited on 03 Dec 2013
13 in the past twelve months

Full-text downloads displays the total number of times this work’s files (e.g., a PDF) have been downloaded from QUT ePrints as well as the number of downloads in the previous 365 days. The count includes downloads for all files if a work has more than one.

ID Code: 60771
Item Type: Journal Article
Refereed: Yes
DOI: 10.1186/1471-2334-13-543
Divisions: Current > Institutes > Institute of Health and Biomedical Innovation
Copyright Owner: © 2013 O’Grady et al.; licensee BioMed Central Ltd.
Copyright Statement: This is an open access article distributed under the terms of the Creative Commons Attribution License (, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Deposited On: 03 Dec 2013 06:23
Last Modified: 09 Apr 2014 12:21

Export: EndNote | Dublin Core | BibTeX

Repository Staff Only: item control page