Michael Hoelscher

Prof. Michael Hoelscher

orcid

Research Focus & Metrics

Academic Career Length

20Years (2007-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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8 March 2020 in medRxiv
Verified
Preprint
Open access
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RWRoman Wölfel
Roman Wölfel
VCVictor M Corman
Victor M Corman
WGWolfgang Guggemos
Wolfgang Guggemos
MSMichael Seilmaier
Michael Seilmaier
SZSabine Zange
Sabine Zange
CWClemens-Martin Wendtner
Clemens-Martin Wendtner
Coronavirus disease 2019 (COVID-19) is an acute respiratory tract infection that emerged in late 2019 1,2 . Initial outbreaks in China involved 13.8% cases with severe-, and 6.1% with critical courses 3 . This severe presentation corresponds to the usage of a virus receptor that is expressed predominantly in the lung 2,4 . By causing an early onset of severe symptoms, this same receptor tropism is thought to have determined pathogenicity but also aided the control of severe acute respiratory syndrome (SARS) in 2003 5 . However, there are reports of COVID-19 cases with mild upper respiratory tract symptoms, suggesting a potential for pre- or oligosymptomatic transmission 6-8 . There is an urgent need for information on body site - specific virus replication, immunity, and infectivity. Here we provide a detailed virological analysis of nine cases, providing proof of active virus replication in upper respiratory tract tissues. Pharyngeal virus shedding was very high during the first week of symptoms (peak at 7.11 × 10 8 RNA copies per throat swab, day 4). Infectious virus was readily isolated from throat- and lung-derived samples, but not from stool samples in spite of high virus RNA concentration. Blood and urine never yielded virus. Active replication in the throat was confirmed by viral replicative RNA intermediates in throat samples. Sequence-distinct virus populations were consistently detected in throat- and lung samples of one same patient. Shedding of viral RNA from sputum outlasted the end of symptoms. Seroconversion occurred after 6-12 days, but was not followed by a rapid decline of viral loads. COVID-19 can present as a mild upper respiratory tract illness. Active virus replication in the upper respiratory tract puts prospects of COVID-19 containment in perspective.

27 January 2015 in Journal of Antimicrobial Chemotherapy
Verified
Journal Article
Open access
PDF file
NHNorbert Heinrich
Norbert Heinrich
RDRodney Dawson
Rodney Dawson
JBJeannine du Bois
Jeannine du Bois
KNKim Narunsky
Kim Narunsky
GHGary Horwith
Gary Horwith
AOAlphonse Okwera
Alphonse Okwera
SQ109, an asymmetrical diamine, is a novel anti-TB drug candidate. This first study in patients was done to determine safety, tolerability, pharmacokinetics and bacteriological effect of different doses of SQ109 alone and in combination with rifampicin when administered over 14 days. Smear-positive pulmonary TB patients were randomized into six groups of 15 to receive once-daily oral treatment with 75, 150 or 300 mg of SQ109, rifampicin (10 mg/kg body weight), rifampicin plus 150 mg of SQ109, or rifampicin plus 300 mg of SQ109 for 14 days. Patients were hospitalized for supervised treatment, regular clinical, biochemical and electrocardiographic safety assessments, pharmacokinetic profiling and daily overnight sputum collection. SQ109 was safe and generally well tolerated. Mild to moderate dose-dependent gastrointestinal complaints were the most frequent adverse events. No relevant QT prolongation was noted. Maximum SQ109 plasma concentrations were lower than MICs. Exposure to SQ109 (AUC0–24) increased by drug accumulation upon repeated administration in the SQ109 monotherapy groups. Co-administration of SQ109 150 mg with rifampicin resulted in decreasing SQ109 exposures from day 1 to day 14. A higher (300 mg) dose of SQ109 largely outweighed the evolving inductive effect of rifampicin. The daily fall in log cfu/mL of sputum (95% CI) was 0.093 (0.126–0.059) with rifampicin, 0.133 (0.166–0.100) with rifampicin plus 150 mg of SQ109 and 0.089 (0.121–0.057) with rifampicin plus 300 mg of SQ109. Treatments with SQ109 alone showed no significant activity. SQ109 alone or with rifampicin was safe over 14 days. Upon co-administration with rifampicin, 300 mg of SQ109 yielded a higher exposure than the 150 mg dose. SQ109 did not appear to be active alone or to enhance the activity of rifampicin during the 14 days of treatment.

18 February 2022 in Science
Verified
Journal Article
Open access
SRS. Momsen Reincke
S. Momsen Reincke
MYMeng Yuan
Meng Yuan
HKHans-Christian Kornau
Hans-Christian Kornau
VCVictor M Corman
Victor M Corman
SHScott van Hoof
Scott van Hoof
JKJakob Kreye
Jakob Kreye
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Beta variant of concern (VOC) resists neutralization by major classes of antibodies from COVID-19 patients and vaccinated individuals. In this study, serum of Beta-infected patients revealed reduced cross-neutralization of wild-type virus. From these patients, we isolated Beta-specific and cross-reactive receptor-binding domain (RBD) antibodies. The Beta-specificity results from recruitment of VOC-specific clonotypes and accommodation of mutations present in Beta and Omicron into a major antibody class that is normally sensitive to these mutations. The Beta-elicited cross-reactive antibodies share genetic and structural features with wild type–elicited antibodies, including a public VH1-58 clonotype that targets the RBD ridge. These findings advance our understanding of the antibody response to SARS-CoV-2 shaped by antigenic drift, with implications for design of next-generation vaccines and therapeutics.

7 January 2019 in BMC Pulmonary Medicine
Verified
Journal Article
Open access
PDF file
ARAndrea Rachow
Andrea Rachow
OIOlena Ivanova
Olena Ivanova
RWRobert Wallis
Robert Wallis
SCSalome Charalambous
Salome Charalambous
IJIlesh Jani
Ilesh Jani
GCGavin Churchyard
Gavin Churchyard
Up to fifty percent of microbiologically cured tuberculosis (TB) patients may be left with permanent, moderate or severe pulmonary function impairment. Very few studies have systematically examined pulmonary outcomes in patients to understand the pathophysiologic basis and long-term socio-economic consequences of this injury. The planned multi-country, multi-centre observational TB cohort study, aims to advance the understanding of the clinical, microbiological, immunological and socio-economic risk factors affecting long-term outcome of pulmonary TB. It will also determine the occurrence of reversible and irreversible socio-economic consequences to patients, their households and the health sector related to pulmonary TB disease and its treatment. We will enrol up to 1.600 patients with drug sensitive and multidrug-resistant pulmonary TB who are treated according to the local standard of care by the respective National TB Program. Recruitment is taking place at the time of TB diagnosis at four African study clinics located in The Gambia, Mozambique, South Africa and Tanzania. The primary outcome is the proportion of TB patients with severe lung impairment measured by spirometry at 24 months after TB treatment initiation. Biological samples, including sputum, urine and blood, for studying host- and pathogenic risk factors will be collected longitudinally and examined in a nested case-control fashion. A standardized quality of life questionnaire will be used together with a novel version of WHO’s generic patient cost instrument which has been adapted for the longitudinal study design. This study is an integral part of an overall strategy to fill a knowledge gap needed to improve TB treatment outcomes globally. The main scientific goal is to identify the major pathogenic mechanisms associated with poor TB treatment outcomes, so that such pathways can be interrupted to avert long term TB sequelae. National as well as supra-national stakeholders and decision makers have been integrated early in the study planning process to inform future treatment guidelines and national health policies. ClinicalTrials.gov: NCT03251196 , August 16, 2017.

1 July 2015 in BMC Infectious Diseases
Verified
Journal Article
Open access
PDF file
GTGrant Theron
Grant Theron
JPJonny Peter
Jonny Peter
LZLynn Zijenah
Lynn Zijenah
DCDuncan Mwelwa Chanda
Duncan Mwelwa Chanda
CMChacha Mangu
Chacha Mangu
KDKeertan Dheda
Keertan Dheda
The successful cure of tuberculosis (TB) is dependent on adherence to treatment. Various factors influence adherence, however, few are easily modifiable. There are limited data regarding correlates of psychological distress and their association with non-adherence to anti-TB treatment. In a trial of a new TB test, we measured psychological distress (K-10 score), TB-related health literacy, and morbidity (TBscore), prior to diagnosis in 1502 patients with symptoms of pulmonary TB recruited from clinics in Cape Town (n = 419), Harare (n = 400), Lusaka (n = 400), Durban (n = 200), and Mbeya (n = 83). Socioeconomic, demographic, and alcohol usage-related data were captured. Patients initiated on treatment had their DOTS cards reviewed at two-and six-months. 22 %(95 % CI: 20 %, 25 %) of patients had severe psychological distress (K-10 ≥ 30). In a multivariable linear regression model, increased K-10 score was independently associated with previous TB [estimate (95 % CI) 0.98(0.09-1.87); p = 0.0304], increased TBscore [1(0.80, 1.20); p <0.0001], and heavy alcohol use [3.08(1.26, 4.91); p = 0.0010], whereas male gender was protective [-1.47(−2.28, −0.62); p = 0.0007]. 26 % (95 % CI: 21 %, 32 %) of 261 patients with culture-confirmed TB were non-adherent. In a multivariable logistic regression model for non-adherence, reduced TBscore [OR (95 % CI) 0.639 (0.497, 0.797); p = 0.0001], health literacy score [0.798(0.696, 0.906); p = 0.0008], and increased K-10 [1.082(1.033, 1.137); p = 0.0012], and heavy alcohol usage [14.83(2.083, 122.9); p = 0.0002], were independently associated. Culture-positive patients with a K-10 score ≥ 30 were more-likely to be non-adherent (OR = 2.290(1.033-5.126); p = 0.0416]. Severe psychological distress is frequent amongst TB patients in Southern Africa. Targeted interventions to alleviate psychological distress, alcohol use, and improve health literacy in newly-diagnosed TB patients could reduce non-adherence to treatment.

28 August 2009 in BMC Infectious Diseases
Verified
Journal Article
Open access
PDF file
KRKlaus Reither
Klaus Reither
ESElmar Saathoff
Elmar Saathoff
JJJutta Jung
Jutta Jung
LMLilian T Minja
Lilian T Minja
IKInge Kroidl
Inge Kroidl
MHMichael Hoelscher
Michael Hoelscher
The development and evaluation of rapid and accurate new diagnostic tools is essential to improve tuberculosis (TB) control in developing countries. In a previous study, the first release of a urine LAM-ELISA by Chemogen (Portland, USA) has been evaluated with a promising sensitivity and specificity for the diagnosis of pulmonary TB. In the present study, the now commercially available assay has been clinically assessed regarding its diagnostic value alone and in combination with clinical co-factors.