Estimates of protection levels against SARS-CoV-2 infection and severe COVID-19 in Germany before the 2022/2023 winter season: the IMMUNEBRIDGE project

PURPOSE

Despite the need to generate valid and reliable estimates of protection levels against SARS-CoV-2 infection and severe course of COVID-19 for the German population in summer 2022, there was a lack of systematically collected population-based data allowing for the assessment of the protection level in real time.

METHODS

In the IMMUNEBRIDGE project, we harmonised data and biosamples for nine population-/hospital-based studies (total number of participants n = 33,637) to provide estimates for protection levels against SARS-CoV-2 infection and severe COVID-19 between June and November 2022. Based on evidence synthesis, we formed a combined endpoint of protection levels based on the number of self-reported infections/vaccinations in combination with nucleocapsid/spike antibody responses ("confirmed exposures"). Four confirmed exposures represented the highest protection level, and no exposure represented the lowest.

RESULTS

Most participants were seropositive against the spike antigen; 37% of the participants ≥ 79 years had less than four confirmed exposures (highest level of protection) and 5% less than three. In the subgroup of participants with comorbidities, 46-56% had less than four confirmed exposures. We found major heterogeneity across federal states, with 4-28% of participants having less than three confirmed exposures.

CONCLUSION

Using serological analyses, literature synthesis and infection dynamics during the survey period, we observed moderate to high levels of protection against severe COVID-19, whereas the protection against SARS-CoV-2 infection was low across all age groups. We found relevant protection gaps in the oldest age group and amongst individuals with comorbidities, indicating a need for additional protective measures in these groups.

Dissemination of carbapenem resistant bacteria from hospital wastewater into the environment

Infections with antibiotic resistant pathogens threaten lives and cause substantial costs. For effective interventions, knowledge of the transmission paths of resistant bacteria to humans is essential. In this study, carbapenem resistant bacteria were isolated from the wastewater of a maximum care hospital during a period of two years, starting in the patient rooms and following the sewer system to the effluent of the wastewater treatment plant (WWTP). The bacteria belonged to six different species and 44 different sequence types (STs). The most frequent STs, ST147 K. pneumoniae (bla_NDM/bla_OXA-48) and ST235 P. aeruginosa (bla_VIM) strains, were present at nearly all sampling sites from the hospital to the WWTP effluent. After core genome multi-locus sequence typing (cgMLST), all ST147 K. pneumoniae strains presented a single epidemiological cluster. In contrast, ST235 P. aeruginosa formed five cgMLST clusters and the largest cluster contained the strain from the WWTP effluent, indicating without doubt, a direct dissemination of both high-risk clones into the environment. Thus, there are - at least two - possible transmission pathways to humans, (i) within the hospital by contact with the drains of the sanitary installations and (ii) by recreational or irrigation use of surface waters that have received WWTP effluent. In conclusion, remediation measures must be installed at both ends of the wastewater system, targeting the drains of the hospital as well as at the effluent of the WWTP.

Bacteria isolated from hospital, municipal and slaughterhouse wastewaters show characteristic, different resistance profiles

Multidrug-resistant bacteria cause difficult-to-treat infections and pose a risk for modern medicine. Sources of multidrug-resistant bacteria include hospital, municipal and slaughterhouse wastewaters. In this study, bacteria with resistance to 3rd generation cephalosporins were isolated from all three wastewater biotopes, including a maximum care hospital, municipal wastewaters collected separately from a city and small rural towns and the wastewaters of two pig and two poultry slaughterhouses. The resistance profiles of all isolates against clinically relevant antibiotics (including β-lactams like carbapenems, the quinolone ciprofloxacin, colistin, and trimethoprim/sulfamethoxazole) were determined at the same laboratory. The bacteria were classified according to their risk to human health using clinical criteria, with an emphasis on producers of carbapenemases, since carbapenems are prescribed for hospitalized patients with infections with multi-drug resistant bacteria. The results showed that bacteria that pose the highest risk, i. e., bacteria resistant to all β-lactams including carbapenems and ciprofloxacin, were mainly disseminated by hospitals and were present only in low amounts in municipal wastewater. The isolates from hospital wastewater also showed the highest rates of resistance against antibiotics used for treatment of carbapenemase producers and some isolates were susceptible to only one antibiotic substance. In accordance with these results, qPCR of resistance genes showed that 90% of the daily load of carbapenemase genes entering the municipal wastewater treatment plant was supplied by the clinically influenced wastewater, which constituted approximately 6% of the wastewater at this sampling point. Likewise, the signature of the clinical wastewater was still visible in the resistance profiles of the bacteria isolated at the entry into the wastewater treatment plant. Carbapenemase producers were not detected in slaughterhouse wastewater, but strains harboring the colistin resistance gene mcr-1 could be isolated. Resistances against orally available antibiotics like ciprofloxacin and trimethoprim/sulfamethoxazole were widespread in strains from all three wastewaters.

Evaluation of the antimicrobial activity and compressive strength of a dental cement modified using plant extract mixture

Literature lacks sufficient data regarding addition of natural antibacterial agents to glass ionomer cement (GICs). Hence, the aim of the study was to increase the antimicrobial properties of GICs through its modification with mixture of plant extracts to be evaluated along with an 0.5% chlorohexidine-modified GIC (CHX-GIC) with regard to biological and compressive strength properties. Conventional GIC (freeze-dried version) and CHX were used. Alcoholic extract of Salvadora persica, Olea europaea, and Ficus carcia leaves were prepared using a Soxhlet extractor for 12 h. The plant extract mixture (PE) was added in three different proportions to the water used for preparation of the dental cement (Group 1:1 PE, 2:1 PE, and 1:2 PE). Specimens were then prepared and tested against the unmodified GIC (control) and the 0.5% CHX-GIC. Chemical analysis of the extract mixture was performed using Gas chromatography-mass spectrometry. Antimicrobial activity was evaluated using agar diffusion assay against Micrococcus luteus and Streptoccocus mutans. Compressive strength was evaluated according to ISO 9917-1:2007 using a Zwick testing machine at a crosshead speed of 0.5 mm/min. Antimicrobial activity against Streptoccocus mutans was significantly increased for all the extract-modified materials compared to the unmodified cement, and the highest concentration was comparable to the CHX-GIC mixture. The activity against Micrococcus luteus was also significantly increased, but only for the material with the highest extract concentration, and here the CHX-GIC group showed statistically the highest antimicrobial activity. Compressive strength results revealed that there was no statistically significant difference between the different mixtures and the control except for the highest tested concentration that showed the highest mean values. The plant extracts (PEs) enhanced the antimicrobial activity against S. mutans and also against M. luteus in the higher concentration while compressive strength was improved by addition of the PE at higher concentrations.

Analysis of time-to-treatment discontinuation of targeted therapy, immunotherapy, and chemotherapy in clinical trials of patients with non-small-cell lung cancer

BACKGROUND

Pragmatic end points, such as time-to-treatment discontinuation (TTD), defined as the date of starting a medication to the date of treatment discontinuation or death has been proposed as a potential efficacy end point for real-world evidence (RWE) trials, where imaging evaluation is less structured and standardized.

PATIENTS AND METHODS

We studied 18 randomized clinical trials of patients with metastatic non-small-cell lung cancer (mNSCLC), initiated after 2007 and submitted to U.S. Food and Drug Administration. TTD was calculated as date of randomization to date of discontinuation or death and compared to progression-free survival (PFS) and overall survival (OS) across all patients, as well as in treatment-defined subgroups [EGFR mutation-positive treated with tyrosine kinase inhibitor (TKI), EGFR wild-type treated with TKI, ALK-positive treated with TKI, immune checkpoint inhibitor (ICI), chemotherapy doublet with maintenance, chemotherapy monotherapy].

RESULTS

Overall across 8947 patients, TTD was more closely associated with PFS (r = 0.87, 95% CI 0.86-0.87) than with OS (0.68, 95% CI 0.67-0.69). Early TTD (PFS-TTD ≥ 3 months) occurred in 7.7% of patients overall, and was more common with chemo monotherapy (15.0%) while late TTD (TTD-PFS ≥ 3 months) occurred in 6.0% of patients overall, and was more common in EGFR-positive and ALK-positive patients (12.4% and 22.9%). In oncogene-targeted subgroups (EGFR positive and ALK positive), median TTDs (13.4 and 14.1 months) exceeded median PFS (11.4 and 11.3 months).

CONCLUSIONS

At the patient level, TTD is associated with PFS across therapeutic classes. Median TTD exceeds median PFS for biomarker-selected patients receiving oncogene-targeted therapies. TTD should be prospectively studied further as an end point for pragmatic randomized RWE trials only for continuously administered therapies.

Monitor position in laparoscopic surgery

BACKGROUND

One of the key problems in laparoscopy is the ergonomic positioning of the monitor. In this study we tested task performance and muscle strain of subjects in relation to monitor position during laparoscopic surgery.

METHODS

Eighteen subjects simulated laparoscopic suturing by threading tiny pearls with a curved needle. This was repeated in three monitor positions (15 min each): frontal at eye level (A), frontal in height of the operating field (B), and 45 degrees to the right side at eye level (C). Subjects were not allowed to turn their heads during these sessions. After the test they were asked for their preferred monitor position. During all tests the electromyographic (EMG) activity of the main neck muscles was recorded and the number of pearls was counted.

RESULTS

The EMG activity was significantly lower for position A compared to positions C and B (p < 0.05). No significant difference was found between positions B and C. The number of threaded pearls as an indicator for task performance was highest for position B. The difference was statistically significant compared to position C (p = 0.0008) but not between positions A and C (p = 0.0508) or A and B (p = 0.0575). When asked for the preferred monitor position, nine subjects chose two monitors in the frontal positions A and B. No subject preferred the monitor at the side position (C).

CONCLUSION

Regarding EMG data, the monitor positioned frontal at eye level is preferable. Reflecting personal preferences of subjects and task performance, it should be of advantage to place two monitors in front of the surgeon: one in position A for lowest neck strain and the other in position B for difficult tasks with optimal task performance. The monitor position at the side is not advisable.

[Transcranial Doppler ultrasound as monitoring during carotid operation]

We describe our method of transcranial Doppler (TCD) monitoring during carotid endarterectomy (CE) procedures. During a period of 35 months we performed 257 CE with TCD monitoring. Critical flow values during crossclamping of the internal carotid artery (ICA) and the necessity of insertion of an intraluminal shunt were taken in consideration with regard to the choice of surgical procedure: TEA (with or without patching) or eversion endarterectomy. The critical flow values were around 10-15 cm/s, no pulsatility signs were detected. Further advantages of the TCD monitoring are: detection of microemboli, control of the potential collateralisation of the external carotid artery and the control of efficacy and accurate positioning of the intraluminal shunt. We comment our results of cerebral monitoring and consider it as a useful tool for optimizing the postoperative results of carotid surgery.

[Necrosis-Q in the mapping ECG]

In this study 57 test persons 15 healthy ones, 42 patients with myocardial infarction with disturbances of the wall excursion) were examined by means of the mapping ECG, the classical ECG and the echocardiography. Considering the healthy test persons the normal values of the Q-deflections were established for every individual lead of the mapping ECG and of this the borderline values for the necrosis-Q (Q less than Q(m-1 s] were derived. The topographic coordination was performed with the help of a computer-aided picture of the thoracic surface. The determination of the localization of an echocardiographically proved disturbance of the wall excursion by means of the mapping ECG on the basis of the borderline values stated for the Q-deflections was carried out with an efficiency of 0.810 and by means of the classical ECG with an efficiency of 0.690. The information of the Q-deflections in the mapping ECG about the presence of an echocardiographically provable disturbance of the wall excursion is possible with an efficiency of 0.833. For the diagnosis of an infarction all infarction-typical parameters should always be used simultaneously. The clinical significance of the diagnostics of myocardial infarction by means of the mapping ECG lies in the exact localisation, the gradual valuation of the size of the infarction, in the recognition of changed potential distribution pattern as sign of the activity of a coronary heart disease with the complication of a myocardial infarction and the establishment of smaller as well as nontransmural myocardial infarctions with non-invasive methods.

[ECG mapping in heart muscle hypertrophy]

67 test persons (15 healthy persons, 52 patients with coronary heart disease, of them 28 patients with and 24 patients without myocardial hypertrophy) were examined by means of a mapping ECG (69 leads) and the echocardiography. For every individual lead of the mapping ECG the mean values and simple scattering of the R and S potentials of 15 normal persons have been established. Of this we led the limit values for left heart and right heart hypertrophy for every individual lead. We are able to make evident that for the determination of a myocardial hypertrophy the principle of Sokolow's index can be transferred to R (max) and S (min) of the mapping ECG. A quantification of the myocardial hypertrophy by means of the R-potential summation method presupposes a correction of the normal potential decrease in the cardio-electric field. A regionally differently characterized myocardial hypertrophy can be recognized with the help of the mapping ECG. By means of an exercise-induced mapping ECG hypertrophy-caused repolarisation disturbances can highly significantly be demarcated (p less than 0.001) from ischaemia-caused ones. The difference mapping is suitable as mapping ECG documentation for a myocardial hypertrophy.

[Gradual evaluation of repolarization disorders with ECG mapping]

143 test persons, (31 healthy persons, 30 borderline cases and 82 patients with chronic coronary heart disease) were examined at rest and on submaximal exertion by means of a mapping ECG (72 electrodes) and their findings were valuated depending upon the severity of the chronic coronary heart disease. The significance of the individual mapping ECG parameters in gradually valuating the disturbances of repolarisation was stated by correlation to the severity of the chronic heart disease and decreased in following order: 1. relative surfaces, 2. total surface with ST decrease in mV, 3. maximum decrease of ST, 4.4. sum of the decrease of ST in mV, 5. sum of negative area integrals of ST and 6. the minimum quotient of increase. The extension of a myocardial ischaemia could be stated with the total area by means of decreases of ST and its maximum by means of the maximal decrease of ST. The severity of the coronary heart disease could be gradually estimated with the "relative surfaces" of the mapping ECG at rest in mild to moderate degrees of severity and under submaximal exertion in all degrees of severity of the coronary heart disease. In a gradual evaluation of the mapping ECG the extension, the intensity, localisation and kind of the disturbance of the myocardium must be considered with regard to the dipole behaviour and to the potential decrease of the cardioelectric field as well as to the degree of severity of the disease.

[Comparison between classical ECG and ST mapping]

In a group of patients with chronic ischaemic heart disease whose diagnoses were ascertained by the clinic, by the electrocardiogram after resting and after work, by the coronarography and/or by the complication of the ischaemic heart disease (myocardial infarction), we compared the findings of the classical ECG with those ones of the ST-mapping. In 32% the ST-mapping brought an increased evidence. A correspondence of 100% we found in the certainly normal and certainly pathological findings. The maxima of the repolarisation disturbances withdrew from the proof of the Wilson derivations at rest at 54.8% and under submaximal strain at 79.3%, changed in 25.8% their position under load and during the load the emigrated in 16.5% out of the precordial leads after Wilson. The evaluated sums of the partial surfaces of the ST-mapping have a higher correlation to the severity of the ischaemic heart disease, permit a better differentiation between the individual degress of severity and render possible an exacter judgment of the prephase of the ischaemic heart disease than it is possible with the usual ECG. In 25.8% of all examinations after work repolarisation disturbances limited to small myocardiac areas could be proved only by means of the mapping. The localisation of lesions of the myocardium is better possible by means of the ST-mapping above all dorsally/caudally than by means of the classical ECG.