Evaluation prompting transition from enhanced to routine surveillance of lymphogranuloma venereum (LGV) in the Netherlands.

In 2004, a lymphogranuloma venereum (LGV) epidemic among men who have sex with men in the Netherlands motivated the introduction of enhanced surveillance. We evaluated the acceptability of the enhanced LGV surveillance in the Netherlands in 2004-2005 to provide recommendations for future surveillance. Completeness of requested patient information was analysed.

Helicobacter pylori genome variability in a framework of familial transmission.

Background: Helicobacter pylori infection is exceptionally prevalent and is considered to be acquired primarily early in life through person-to-person transmission within the family. H. pylori is a genetically diverse bacterial species, which may facilitate adaptation to new hosts and persistence for decades.

Helicobacter pylori occurrence and transmission: a family affair?

About half of the world's population is estimated to be infected with Helicobacter pylori, a gastric bacterium that contributes to the development of peptic ulcer disease and gastric cancer. H. pylori is more prevalent in low-income areas of the world and social and economic development decreases the prevalence as reflected in comparisons both within and between countries.

Accommodation of additional non-randomly sampled cases in a study of Helicobacter pylori infection in families.

Epidemiological studies with two-stage designs typically gather information about some covariates from all study subjects in the first sampling stage, while additional data from only a subset of the subjects are collected in the second sampling stage. Appropriate analysis of two-stage studies maintains validity and can also improve precision. We describe an application of a weighted likelihood method, mean-score logistic regression, to accommodate data from a cross-sectional study of Helicobacter pylori infection in children, where the study sample was enriched with additional non-randomly sampled cases.

Concordance of Helicobacter pylori strains within families.

Helicobacter pylori infection is typically acquired in early childhood, and a predominantly intrafamilial transmission has been postulated. To what extent family members share the same strains is poorly documented. Our aim was to explore patterns of shared strains within families by using molecular typing.

Determining the genomic locations of repetitive DNA sequences with a whole-genome microarray: IS6110 in Mycobacterium tuberculosis.

The mycobacterial insertion sequence IS6110 has been exploited extensively as a clonal marker in molecular epidemiologic studies of tuberculosis. In addition, it has been hypothesized that this element is an important driving force behind genotypic variability that may have phenotypic consequences. We present here a novel, DNA microarray-based methodology, designated SiteMapping, that simultaneously maps the locations and orientations of multiple copies of IS6110 within the genome.