Laboratory-based surveillance in the molecular era: the TYPENED model, a joint data-sharing platform for clinical and public health laboratories

Laboratory-based surveillance, one of the pillars of monitoring infectious disease trends, relies on data produced in clinical and/or public health laboratories. Currently, diagnostic laboratories worldwide submit strains or samples to a relatively small number of reference laboratories for characterisation and typing. However, with the introduction of molecular diagnostic methods and sequencing in most of the larger diagnostic and university hospital centres in high-income countries, the distinction between diagnostic and reference/public health laboratory functions has become less clear-cut. Given these developments, new ways of networking and data sharing are needed. Assuming that clinical and public health laboratories may be able to use the same data for their own purposes when sequence-based testing and typing are used, we explored ways to develop a collaborative approach and a jointly owned database (TYPENED) in the Netherlands. The rationale was that sequence data - whether produced to support clinical care or for surveillance -can be aggregated to meet both needs. Here we describe the development of the TYPENED approach and supporting infrastructure, and the implementation of a pilot laboratory network sharing enterovirus sequences and metadata.

Comparison of sequence analysis and INNO-LiPA HBV DR line probe assay in patients with chronic hepatitis B

The aim of this study was to compare direct sequence analysis of partial HBV pol gene and Inno-LiPA HBV DR in serum samples of 120 chronic hepatitis B patients sent to the Clinical Microbiology Laboratory of Ege University Hospital because of lamivudine resistance. Sequence analysis was performed on ABI Prism 310 Genetic Analyzer. Comparison of Inno-LiPA and sequence results obtained by double-blind evaluation showed full agreement (both at rt180 and rt204) in 58.8% of samples. Visually rechecking of the electropherograms increased this rate to 68.3% Codon based rates are 81.7% and 75.8% at rt180 and rt204 respectively. LiPA detected variants in additional 12 (10%) samples, but missed one variant sample (both rt180 and rt204) and one sample was indeterminate due to poor probe binding. LiPA allows determination of mixed variants and seems to be more sensitive and simple for routine testing even though sequence analysis is still the gold standard for detecting new variants.

[Evaluation of the agreement of results obtained from ABI Prism 7000 and 7700 sequencers in the quantification of hepatitis B virus DNA]

There are different methods and systems for quantification of HBV-DNA in clinical virology laboratories. The aim of this study was to evaluate the agreement of the polymerase chain reaction (PCR) protocol with ABI Prism 7000 instrument (PE Biosystems) which was designed and optimised for ABI Prism 7700 (PE Biosystems). Serum samples obtained from 168 chronic hepatitis B patients were treated with "High Pure Viral Nucleic Acid Kit" (Roche Applied Science, USA), and MagnaPure LC isolation station (Roche Applied Science, Germany) was used for HBV-DNA isolation. Real time PCR procedure which amplifies pre-S gene of HBV genome was performed. Amplification and detection steps of all samples were performed with ABI Prism 7700 and 7000 Sequence Detection Systems. Among 168 samples, results of 124 serum samples were found to be in dynamic ranges of the tests. The results of these 124 samples obtained from ABI 7000 and ABI 7700 were concordant. Among the rest of 44 samples; one yielded higher than 10(10) copies/mL with two of the systems; six samples gave results higher than 10(10) copies/mL only with 7700; thirty samples were found negative with both of the systems; seven samples were positive (320-1220 copies/mL) with 7000 but negative with 7700. As a result this PCR protocol can be used in ABI 7000 system according to viral quality control (VQC) results. However, since the results of samples with HBV-DNA less than 1 x 10(6) copy/ml were discordant with the results obtained by ABI 7700 system, it can be concluded that different systems must not be used for the management and monitoring of the same patient.