Conservation with elevated elephant densities sequesters carbon in soils despite losses of woody biomass.

Nature conservation and restoration in terrestrial ecosystems is often focused on increasing the numbers of megafauna, expecting them to have positive impacts on ecological self-regulation processes and biodiversity. In sub-Saharan Africa, conservation efforts also aspire to protect and enhance biodiversity with particular focus on elephants. However, elephant browsing carries the risk of woody biomass losses. In this context, little is known about how increasing elephant numbers affects carbon stocks in soils, including the subsoils. We hypothesized that (1) increasing numbers of elephants reduce tree biomass, and thus the amount of C stored therein, resulting (2) in a loss of soil organic carbon (SOC). If true, a negative carbon footprint could limit the sustainability of elephant conservation from a global carbon perspective. To test these hypotheses, we selected plots of low, medium, and high elephant densities in two national parks and adjacent conservancies in the Namibian component of the Kavango Zambezi Transfrontier Area (KAZA), and quantified carbon storage in both woody vegetation and soils (1 m). Analyses were supplemented by the assessment of soil carbon isotopic composition. We found that increasing elephant densities resulted in a loss of tree carbon storage by 6.4 t ha-1 . However, and in contrast to our second hypothesis, SOC stocks increased by 4.7 t ha-1 with increasing elephant densities. These higher SOC stocks were mainly found in the topsoil (0-30 cm) and were largely due to the formation of SOC from woody biomass. A second carbon input source into the soils was megaherbivore dung, which contributed with 0.02-0.323 t C ha-1  year-1 to ecosystem carbon storage in the low and high elephant density plots, respectively. Consequently, increasing elephant density does not necessarily lead to a negative C footprint, as soil carbon sequestration and transient C storage in dung almost compensate for losses in tree biomass.

[Recording of SARS-CoV-2 laboratory tests in Germany]. / Erfassung der Labortestungen auf SARS-CoV-2 in Deutschland.

The collection of data on SARS-CoV­2 tests is central to the assessment of the infection rate in the context of the COVID-19 pandemic. At the Robert Koch Institute (RKI), data collected from various laboratory data recording systems are consolidated. First, this article aims to exemplify significant aspects regarding test procedures. Subsequently the different systems for recording laboratory tests are described and test numbers from the RKI test laboratory query and the laboratory-based SARS-CoV­2 surveillance as well as accounting data from the Association of Statutory Health Insurance Physicians for SARS-CoV­2 laboratory tests are shown.Early in the pandemic, the RKI test laboratory query and the laboratory-based SARS-CoV­2 surveillance became available and able to evaluate data on performed tests and test capacities. By recording the positive and negative test results, statements about the total number of tests and the proportion of positive test rates can be made. While the aggregate test numbers are largely representative nationwide, they are not always representative at the state and district level. The billing data of the Association of Statutory Health Insurance Physicians can complement the laboratory data afterwards. In addition, it can provide a retrospective assessment of the total number of SARS-CoV­2 numbers in Germany, because the services provided by statutory health insurers (around 85% of the population in Germany) are included. The various laboratory data recording systems complement one another and the evaluations flow into the recommended measures for the pandemic response.

Reconstruction of the Genetic History and the Current Spread of HIV-1 Subtype A in Germany.

HIV-1 non-B infections have been increasing in Europe for several years. In Germany, subtype A belongs to the most abundant non-B subtypes showing an increasing prevalence of 8.3% among new infections in 2016. Here we trace the origin and examine the current spread of the German HIV-1 subtype A epidemic. Bayesian coalescence and birth-death analyses were performed with 180 German HIV-1 pol sequences and 528 related and publicly available sequences to reconstruct the population dynamics and fluctuations for each of the transmission groups. Our reconstructions indicate two distinct sources of the German subtype A epidemic, with an Eastern European and an Eastern African lineage both cocirculating in the country. A total of 13 German-origin clusters were identified; among these, 6 clusters showed recent activity. Introductions leading to further countrywide spread originated predominantly from Eastern Africa when introduced before 2005. Since 2005, however, spreading introductions have occurred exclusively within the Eastern European clade. Moreover, we observed changes in the main route of subtype A transmission. The beginning of the German epidemic (1985 to 1995) was dominated by heterosexual transmission of the Eastern African lineage. Since 2005, transmissions among German men who have sex with men (MSM) have been increasing and have been associated with the Eastern European lineage. Infections among people who inject drugs dominated between 1998 and 2005. Our findings on HIV-1 subtype A infections provide new insights into the spread of this virus and extend the understanding of the HIV epidemic in Germany.IMPORTANCE HIV-1 subtype A is the second most prevalent subtype worldwide, with a high prevalence in Eastern Africa and Eastern Europe. However, an increase of non-B infections, including subtype A infections, has been observed in Germany and other European countries. There has simultaneously been an increased flow of refugees into Europe and especially into Germany, raising the question of whether the surge in non-B infections resulted from this increased immigration or whether German transmission chains are mainly involved. This study is the first comprehensive subtype A study from a western European country analyzing in detail its phylogenetic origin, the impact of various transmission routes, and its current spread. The results and conclusions presented provide new and substantial insights for virologists, epidemiologists, and the general public health sector. In this regard, they should be useful to those authorities responsible for developing public health intervention strategies to combat the further spread of HIV/AIDS.

[How many people have been tested for HIV in the outpatient sector in Germany?] / Wie viele Personen lassen sich in Deutschland im niedergelassenen Bereich auf HIV testen?

BACKGROUND: Estimating the number of persons tested for HIV in Germany is challenging. HIV testing can be reimbursed by statutory health insurance (SHI) under certain circumstances. This study aimed to use SHI physician claims data to determine the number of persons tested in the outpatient sector. METHODS: The Central Research Institute for Ambulatory Health Care in Germany (Zi) aggregated a dataset of persons tested for HIV among all SHI insurees. Descriptive analysis differentiated between screening and confirmatory HIV tests. Time trends were explored using linear regression. Insurees with confirmatory tests were compared to newly diagnosed HIV (ndHIV) cases. RESULTS: Between 2010 and 2015, 1.7% of insurees were annually screened by SHI physicians. Screening tests increased significantly between 2010 and 2015. Among persons screened, 82.5% were women and of those 81.2% had a screening test during pregnancy. Confirmatory tests were performed on 16,034 insurees (0.3% with screening test; 51.2% men). A total of 18,446 (82.8% men) ndHIV cases were notified between 2010 and 2015. CONCLUSIONS: For the first time, the number of persons with HIV tests in the SHI sector was estimated. The high number of screened women is due to tests during pregnancy. The higher number of ndHIV cases indicates an unknown number of persons tested at other testing sites.

Surveillance of recent HIV infections among newly diagnosed HIV cases in Germany between 2008 and 2014.

BACKGROUND: The HIV surveillance system in Germany is based on mandatory, anonymous notification of newly diagnosed HIV cases by laboratories. Because the time between HIV infection and the diagnosis of HIV varies widely between persons, it is difficult to determine the number of cases of recent HIV infection among newly diagnosed cases of HIV. In Germany, the BED-capture-enzyme immunoassay (BED-CEIA) has been used to distinguish between recent and long-standing HIV infection. The aim of this analysis is to report the proportion of cases of recent HIV infection among newly diagnosed cases in Germany between 2008 and 2014 and to identify factors associated with recent infections. METHODS: A sample of voluntary laboratories among all HIV diagnostic laboratories was recruited. Residual blood from HIV diagnostic tests was spotted on filter paper as dried serum or dried plasma spots and was sent along with the notification form of the HIV cases. The BED-CEIA test was performed. A case was defined as recent HIV infection with a BED-CEIA test result of less than 0.8 normalized optical density, with the exclusion of CDC stage C. The proportion of recent newly diagnosed HIV infections among different groups (such as transmission groups, gender or age groups) was calculated. We used logistic regression to identify factors associated with recent HIV infection and to identify subpopulations with high proportions of recent HIV infections. RESULTS: Approximately 10,257 newly diagnosed cases were tested for recency using the BED-CEIA. In total, 3084 (30.4%) of those were recently infected with HIV. The highest proportion of recent HIV infections was found among men who had sex with men (MSM) (35%) and persons between 18 and 25 years of age (43.0%). Logistic regression revealed that female German intravenous drug users with a recent HIV infection had a higher chance of being detected than German MSM (OR 2.27). CONCLUSIONS: Surveillance of recent HIV infection is a useful additional tool to monitor the HIV epidemic in Germany. We could observe ongoing HIV transmission in Germany in general and in different subgroups, and we could identify factors associated with recent HIV infection in Germany.

National molecular surveillance of recently acquired HIV infections in Germany, 2013 to 2014.

To enable an up-to-date molecular analysis of human immunodeficiency virus (HIV) genotypes circulating in Germany we have established a surveillance system based on recently acquired HIV infections. New HIV infections are reported to the Robert Koch Institute as a statutory duty for anonymous notification. In 2013 and 2014, a dried serum spot (DSS) sample was received from 6,371 newly diagnosed HIV-cases; their analysis suggested that 1,797 samples originated from a recent infection. Of these, 809 were successfully genotyped in the pol region to identify transmitted drug resistance (TDR) mutations and to determine the HIV-1 subtype. Total TDR was 10.8%, comprising 4.3% with mono-resistance to nucleoside reverse transcriptase inhibitors (NRTIs), 2.6% to non-NRTIs, 3.0% to protease inhibitors and 0.6% and 0.2%, respectively, with dual- and triple-class resistances. HIV-1 subtype B was most prevalent with 77.0%. Non-B infections were identified more often in men and women with heterosexual transmission compared with intravenous drug users or men who have sex with men (79% and 76%, 33%, 12%; all p < 0.05). Non-B subtypes were also more frequently found in patients originating from countries other than Germany (46% vs 14%; p < 0.05) and in patients infected outside of Germany (63% vs 14%; p < 0.05).

Identification of soil contamination hotspots with veterinary antibiotics using heavy metal concentrations and leaching data--a field study in China.

In regions with high livestock densities, the usage of antibiotics and metals for veterinary purposes or as growth promoters poses a risk in manured soils. We investigated to which degree the concentrations and depth distributions of Cu, Zn, Cr and As could be used as a tracer to discover contaminations with sulfonamides, tetracyclines and fluoroquinolones. Besides, we estimated the potential vertical translocation of antibiotics and compared the results to measured data. In the peri-urban region of Beijing, China, soil was sampled from agricultural fields and a dry riverbed contaminated by organic waste disposal. The antibiotic concentrations reached 110 µg kg(-1) sulfamethazine, 111 µg kg(-1) chlortetracycline and 62 µg kg(-1) enrofloxacin in the topsoil of agricultural fields. Intriguingly, total concentrations of Cu, Zn, Cr and As were smaller than 65, 130, 36 and 10 mg kg(-1) in surface soil, respectively, therewith fulfilling Chinese quality standards. Correlations between sulfamethazine concentrations and Cu or Zn suggest that in regions with high manure applications, one might use the frequently existing monitoring data for metals to identify potential pollution hotspots for antibiotics in topsoils. In the subsoils, we found sulfamethazine down to ≥2 m depth on agricultural sites and down to ≥4 m depth in the riverbed. As no translocation of metals was observed, subsoil antibiotic contamination could not be predicted from metal data. Nevertheless, sulfonamide stocks in the subsoil could be estimated with an accuracy of 35-200 % from fertilisation data and potential leaching rates. While this may not be sufficient for precise prediction of antibiotic exposure, it may very well be useful for the pre-identification of risk hotspots for subsequent in-depth assessment studies.

Sirolimus versus paclitaxel coronary stents in clinical practice.

OBJECTIVES: We aimed at comparing the long term clinical outcome of SES and PES in routine clinical practice. BACKGROUND: Although sirolimus-eluting stents (SES) more effectively reduce neointimal hyperplasia than paclitaxel-eluting stents (PES), uncertainty prevails whether this difference translates into differences in clinical outcomes outside randomized controlled trials with selected patient populations and protocol-mandated angiographic follow-up. METHODS: Nine hundred and four consecutive patients who underwent implantation of a drug-eluting stent between May 2004 and February 2005: 467 patients with 646 lesions received SES, 437 patients with 600 lesions received PES. Clinical follow-up was obtained at 2 years without intervening routine angiographic follow-up. The primary endpoint was a composite of death, myocardial infarction (MI), or target vessel revascularization (TVR). RESULTS: At 2 years, the primary endpoint was less frequent with SES (12.9%) than PES (17.6%, HR = 0.70, 95% CI 0.50-0.98, P = 0.04). The difference in favor of SES was largely driven by a lower rate of target lesion revascularisation (TLR; 4.1% vs. 6.9%, P = 0.05), whereas rates of death (6.4% vs. 7.6%, P = 0.49), MI (1.9% vs. 3.2%, P = 0.21), or definite stent thrombosis (0.6% vs. 1.4%, P = 0.27) were similar for both stent types. The benefit regarding reduced rates of TLR was significant in nondiabetic (3.6% vs. 7.1%, P = 0.04) but not in diabetic patients (5.6% vs. 6.1%, P = 0.80). CONCLUSIONS: SES more effectively reduced the need for repeat revascularization procedures than PES when used in routine clinical practice. The beneficial effect is maintained up to 2 years and may be less pronounced in diabetic patients.

Highly variable use of diagnostic methods for sexually transmitted infections-results of a nationwide survey, Germany 2005.

BACKGROUND: Sexual transmitted infections (STIs) have increased in Germany and other countries in Europe since the mid-nineties. To obtain a better picture of diagnostic methods used in STI testing institutions in Germany, we performed a nationwide survey amongst STI specialists in order to evaluate the quality of STI reports and provide recommendations to harmonize and possibly improve STI diagnostics in Germany. METHODS: We asked sentinel physicians and randomly chosen gynaecologists, urologists and dermato-venerologists, about the diagnostic methods used in 2005 to diagnose HIV, chlamydia (CT), gonorrhoea (GO) and syphilis (SY) in a national cross-sectional survey in order to recognize potential problems and provide recommendations. RESULTS: A total of 739/2287 (32%) physicians participated. Of all participants, 80% offered tests for HIV, 84% for CT, 83% for GO and 83% for SY. Of all participants who performed HIV testing, 90% requested an antibody test, 3% a rapid test and 1% a nucleic acid amplification test (NAAT). For CT testing, NAAT was used in 33% and rapid tests in 34% of participants. GO resistance testing was performed by 31% of the participants. SY testing was performed in 98% by serology. CONCLUSIONS: Diagnostic methods for STI vary highly among the participants. Diagnostic guidelines should be reviewed and harmonised to ensure consistent use of the optimal STI diagnostic methods.

Evaluation of a BioRad Avidity assay for identification of recent HIV-1 infections using dried serum or plasma spots.

Serological methods to differentiate between recently acquired and established HIV-1 infections are a useful tool in the HIV-surveillance to characterize the epidemic, identify groups at risk and assess HIV-preventive interventions. Therefore, an avidity-based, modified BioRad Genscreen™ HIV-1/2 assay (BRAEUR) was evaluated according to the avidity-based, modified BioRad HIV-1/2 Plus O protocol (BRAUSA). Overall, 692 well defined samples (82.5% B and 17.5% non-B subtypes) from recent (<180 days, n = 239), intermediate (181-364 days, n = 35) or long term infections (≥365 days, n = 419) were used to determine a 'mean duration of recent infection' (MDRI), a 'median DRI' (MdDRI), the false recent rate (FRR), and concordance between the BRAs and the Sedia BED HIV-1 Capture enzyme immunoassay (BED). The optimal avidity index cut-off was determined to be 70% resulting in an MDRI of 233 days (95% IQR: 174-351) and an MdDRI of 171 days (95% IQR: 142-212). Concordance with the BRAUSA was high with 96.4%. The FRR of 6.0% as well as the MdDRI are similar to the BED (8.4%; 170 (139-214) days). Therefore, the BRAEUR is a suitable alternative to replace the BED and trend analysis will be feasible after minimal adjustments for the MdDRI and the MDRI.

Increasing proportions of HIV-1 non-B subtypes and of NNRTI resistance between 2013 and 2016 in Germany: Results from the national molecular surveillance of new HIV-diagnoses.

BACKGROUND: Molecular surveillance of newly diagnosed HIV-infections is important for tracking trends in circulating HIV-variants, including those with transmitted drug resistances (TDR) to sustain ART efficacy. METHODS: Dried serum spots (DSS) are received together with the statutory notification of a new diagnosis. 'Recent infections' (<155 days) classified by a 'recent infection test algorithm' (BED-CEIA and clinical data) are genotyped in HIV-protease (PR), reverse transcriptase (RT) and integrase (INT) to determine the HIV-1 subtype, to calculate prevalence and trends of TDR, to predict baseline susceptibility and to identify potential transmission clusters for resistant variants. RESULTS: Between January 2013 and December 2016, 1,885 recent infections were analysed regarding the PR/RT genomic region, with 43.5% of these also being subjected to the analysis of INT. The proportion of HIV-1 non-B viruses (31.3%; 591/1,885) increased from 21.6% to 36.0%, particularly the subtypes A (5.0% to 8.3%) and C (3.2% to 7.7%; all ptrends < 0.01). The subtype A increment is mainly due to transmissions within men who have sex with men (MSM) while subtype C transmissions are associated with heterosexuals and people who inject drugs. The prevalence of TDR was stable at 11.0% (208/1,885) over the study period. Resistances to nucleotide RT inhibitors (NRTI) and PR inhibitors (PI) were 4.5% and 3.2%, respectively, without identifiable trends. In contrast, resistances to non-NRTIs (NNRTI, 4.7%) doubled between 2014 and 2016 from 3.2% to 6.4% (ptrend = 0.02) mainly due to the K103N mutation (from 1.7% to 4.1%; ptrend = 0.03) predominantly detected in recently infected German MSM not linked to transmission clusters. Transmitted INSTI mutations were present in only one case (T66I) and resistance to dolutegravir was not identified at all. Reduced susceptibility to recommended first-line therapies was low with 1.0% for PIs, 1.3% for NRTIs and 0.7% for INSTIs, but high for the NNRTIs efavirence (4.9%) and rilpivirine (6.0%) due to the K103N mutation and the polymorphic mutation E138A. These trends in therapy-naïve individuals impact current first-line regimens and require awareness and vigilant surveillance.

Robust and sensitive subtype-generic HIV-1 pol genotyping for use with dried serum spots in epidemiological studies.

HIV-1 genotyping of larger pol-fragments from dried serum/plasma spots (DSS/DPS) is often hindered by RNA-degradation during transportation at ambient temperature. We evaluated an in-house HIV-1 DSS/DPS-genotyping assay designed in two shorter overlapping fragments covering all resistance mutations in protease and reverse transcriptase. Validation criteria such as specificity, detection limit, accuracy, reproducibility and storage conditions were assessed using reference plasma samples prepared as DPS and clinical DSS from the German molecular HIV-1 surveillance processed under real-life transportation conditions. The specificity was 100% for both samples types, and the experimental DPS detection limit of 1000 copies/ml yielded a 98.7% (3,329/3373) success rate for DSS (including all subtypes) above this detection limit. Accuracy for DPS compared to the gold standard was 99.1% and the reproducibility was 100% for DPS replicates and 99.9% for DSS pairs. Storage of DPS at room temperature was possible for 90 or 30 days and at -20 °C for at least 180 or 90 days at viral loads of 10,000 or 1000 copies/ml, respectively. The HIV-1 pol-genotyping assay presented here is a sensitive, robust and subtype generic tool for a large-scale population-based HIV-1 drug resistance surveillance for the use of DSS/DPS.

Improved testing of recent HIV-1 infections with the BioRad avidity assay compared to the limiting antigen avidity assay and BED Capture enzyme immunoassay: evaluation using reference sample panels from the German Seroconverter Cohort.

BACKGROUND: The variety and limitations of current laboratory methods for estimating HIV-incidence has driven attempts to improve and standardize the performance of serological 'Tests for Recent HIV-Infections' (TRI). Primary and follow-up HIV-1 positive plasma samples from individuals with well-defined dates of infection collected as part of the German Seroconverter Cohort provided specimens highly suitable for use in comparing the performance of three TRIs: the AWARE™ BED™ EIA HIV-1 Incidence test (BED-CEIA), Genetic systems HIV-1/HIV-2 Plus O EIA antibody avidity-based assay (BioRad Avidity) and Sedia™ HIV-1 LAg Avidity EIA (LAg Avidity). METHODS: The evaluation panel included 180 specimens: 44 from antiretroviral (ARV)-naïve individuals with recently acquired HIV-infection (≤ 130 days; 25 B and 19 non-B subtypes) and 136 from long-term (>12 months) infected individuals [101 ARV-naïve subtype B, 16 non-B subtypes, 14 ARV-treated individuals, 5 slow progressors (SLP)]. RESULTS: For long-term infected, ARV-naïve individuals the false recent rates (FRR) of both the BioRad and LAg Avidity assays were 2% (2/101 for subtype B) and 6% (1/16 for subtype 'non-B'), while the FRR of the BED-CEIA was 7% (7/101 for subtype B) and 25% (4/16 for subtype 'non-B') (all p>0.05). Misclassification of ARV-treated individuals and SLP was rare by LAg (1/14, 0/5) and BioRad Avidity assays (2/14, 1/5) but more frequent by BED-CEIA (5/14, 3/5). Among recently-infected individuals (subtype B), 60% (15/25) were correctly classified by BED-CEIA, 88% (22/25) by BioRad Avidity and significantly fewer by LAg (48%, 12/25) compared to BioRad Avidity (p = 0.005) with a higher true-recency rate among non-B infections for all assays. CONCLUSIONS: This study using well-characterized specimens demonstrated lower FRRs for both avidity methods than with the BED-CEIA. For recently infected individuals the BioRad Avidity assay was shown to give the most accurate results.