Harald Wilfing

Secular change in height in Austria: an effect of population stratification?

The records of height on some 700,000 18-year-old Austrian males, called for examination as to their fitness for conscription, were analysed. The data covered 14 conscription years (1980-93), representing males born in the years 1962-75. The sample covered over 90% of the total male population of those cohorts in Austria. The data were analysed by birth year to show the secular trend in 18-year-old stature and its rate, which overall amounted to 0.53 cm/decade. Analysis by urban-rural residence showed that both participated in the trend, but that the urban-rural differences were appreciably less than the differences between the types of school the young men had attended. The rate of increase over the 14 years was less within each of the eight subgroups (urban-rural, four school categories). It is argued that the secular trend in height that has occurred is largely attributable to the change in social stratification, as evidenced by the changed proportion of subjects who attended schools of different types.

Evaluation of a Rapid Dipstick (Crystal VC) for the Diagnosis of Cholera in Zanzibar and a Comparison with Previous Studies

BACKGROUND The gold standard for the diagnosis of cholera is stool culture, but this requires laboratory facilities and takes at least 24 hours. A rapid diagnostic test (RDT) that can be used by minimally trained staff at treatment centers could potentially improve the reporting and management of cholera outbreaks. METHODS We evaluated the Crystal VC™ RDT under field conditions in Zanzibar in 2009. Patients presenting to treatment centers with watery diarrhea provided a stool sample for rapid diagnostic testing. Results were compared to stool culture performed in a reference laboratory. We assessed the overall performance of the RDT and evaluated whether previous intake of antibiotics, intravenous fluids, location of testing, and skill level of the technician affected the RDT results. RESULTS We included stool samples from 624 patients. Compared to culture, the overall sensitivity of the RDT was 93.1% (95%CI: 88.7 to 96.2%), specificity was 49.2% (95%CI: 44.3 to 54.1%), the positive predictive value was 47.0% (95%CI: 42.1 to 52.0%) and the negative predictive value was 93.6% (95%CI: 89.6 to 96.5%). The overall false positivity rate was 50.8% (213/419); fieldworkers frequently misread very faint test lines as positive. CONCLUSION The observed sensitivity of the Crystal VC RDT evaluated was similar compared to earlier versions, while specificity was poorer. The current version of the RDT could potentially be used as a screening tool in the field. Because of the high proportion of false positive results when field workers test stool specimens, positive results will need to be confirmed with stool culture.

Assessment and comparative analysis of a rapid diagnostic test (Tubex ® ) for the diagnosis of typhoid fever among hospitalized children in rural Tanzania

BackgroundTyphoid fever remains a significant health problem in many developing countries. A rapid test with a performance comparable to that of blood culture would be highly useful. A rapid diagnostic test for typhoid fever, Tubex®, is commercially available that uses particle separation to detect immunoglobulin M directed towards Salmonella Typhi O9 lipopolysaccharide in sera.MethodsWe assessed the sensitivity and specificity of the Tubex test among Tanzanian children hospitalized with febrile illness using blood culture as gold standard. Evaluation was done considering blood culture confirmed S. Typhi with non-typhi salmonella (NTS) and non - salmonella isolates as controls as well as with non-salmonella isolates only.ResultsOf 139 samples tested with Tubex, 33 were positive for S. Typhi in blood culture, 49 were culture-confirmed NTS infections, and 57 were other non-salmonella infections. Thirteen hemolyzed samples were excluded. Using all non - S. Typhi isolates as controls, we showed a sensitivity of 79% and a specificity of 89%. When the analysis was repeated excluding NTS from the pool of controls we showed a sensitivity of 79% and a specificity of 97%. There was no significant difference in the test performance using the two different control groups (p > 0.05).ConclusionThis first evaluation of the Tubex test in an African setting showed a similar performance to those seen in some Asian settings. Comparison with the earlier results of a Widal test using the same samples showed no significant difference (p > 0.05) for any of the performance indicators, irrespective of the applied control group.

Priest, hunter, alpine shepherd, or smelter worker?

A sample of hair found with the man from the Hauslabjoch was made available for the determination of inorganic components particularly trace elements. Hair is known to preserve information about the trace element status of an organism. The sulfur (cysteine)-rich organic constituents of hair have high affinities for heavy metals. A high body burden of elements such as copper, lead, and arsenic should be reflected by high concentrations of these elements in hair1. Thus, high concentrations of arsenic in Napoleon’s hair were taken as indication that the emperor had been poisoned by arsenic2. Although nobody expects that the iceman was poisoned, the concentrations of elements in the hair samples could perhaps provide information about the nutritional status with respect to essential elements, about exposures to toxic elements, and about settings leading to such exposures.

Trigonometric analysis of the Human Median Sagittal Plane and its applications in reconstruction and phylogeny

By means of a new method of measurement which defines a total of eight measuring points along the median sagittal plane of the skull, methodical aspects are explained. The advantages of this method consist in its easy use and exact reproducibility of the calculated data thus obtained. On account of the fact that it permits to obtain the median sagittal plane of the skull by means of points of a cartesian system of coordinate, phylogenetic comparison, standardisable on optional points of reference respectively planes of reference is possible. The specific trigonometric construction enables extensive interpretation of single angles, distances and parts of surface, the amount of detail of which exceeds that of method in use.