Severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2)-infection is associated with an extremely variable disease course. When interstitial pneumonia (IP) occurs, it can lead to acute respiratory distress syndrome and death. Serum Krebs von den Lungen-6 (KL-6) is an established marker of IP, but its role as a marker of SARS-CoV-2 pneumonia is debated. This bicentric study included 157 patients with SARS-CoV-2 pneumonia. The WHO Ordinal Scale for Clinical Improvement (0–10 points) was used to classify the clinical course. Serum samples were collected at admission, and on days 3 and 7 of hospitalization. KL-6 was measured by using automated chemiluminescence immunoassay. A total of 68 patients developed a severe SARS-CoV-2 pneumonia, 135 of them required oxygen, and 15 died during hospitalization. The patients requiring non-invasive ventilation, invasive ventilation, or extracorporeal membrane oxygenation had significantly higher serum KL-6 levels at admission. The serum KL-6 levels were tendentially higher in patients who died than in those who survived. Logistic regression identified serum KL-6 at a cut-off of 335 U/mL at admission as a significant predictor of severe SARS-CoV-2 pneumonia outcome. Serum KL-6 seems to be a candidate biomarker for the clinical routine to stratify patients with SARS-CoV-2 pneumonia for the risk of a severe disease outcome or death.

Ticks are important vectors for Rickettsia spp. belonging to the Spotted Fever Group responsible for causing Rickettsiosis worldwide. Rickettsioses pose an underestimated health risk to tourists and local inhabitants. There is evidence of the presence of Rickettsia spp. in Zambia, however there is limited data. A total of 1465 ticks were collected in 20 different locations from dogs and cattle including one cat. Ticks were identified by morphological features or by sequencing of the 16S mitochondrial rRNA gene. Individual ticks were further tested for rickettsiae using a pan-Rickettsia real-time-PCR. Rickettsia species in PCR-positive ticks were identified by sequencing the 23S-5S intergenic spacer region or partial ompA gene, respectively. Seven tick species belonging to three different tick genera were found, namely: Amblyomma variegatum, Rhipicephalus appendiculatus, Rhipicephalus (Boophilus) microplus, Rhipicephalus simus, Rhipicephalus sanguineus, Rhipicephalus zambesiensis and Haemaphysalis elliptica. Out of the 1465 ticks collected, 67 (4.6%) tested positive in the pan-Rickettsia PCR. This study provides detailed data about the presence of Rickettsia species in South Luangwa Valley, Eastern Province, Zambia for the first time. High prevalence of Rickettsia africae in Amblyomma variegatum was found, which indicates the potential risk of infection in the investigated area. Furthermore, to our best knowledge, this is the first time Rickettsia massiliae, a human pathogen causing spotted fever, has been detected in Zambia.

Background: It is widely accepted that SARS-CoV-2 causes a dysregulation of immune and coagulation processes. In severely affected patients, viral sepsis may result in life endangering multiple organ dysfunction. Furthermore, most therapies for COVID-19 patients target either the immune system or coagulation processes. As the exact mechanism causing SARS-CoV-2-induced morbidity and mortality was unknown, we started an in-depth analysis of immunologic and coagulation processes. Methods: 127 COVID-19 patients were treated at the University Hospital Essen, Germany, between May 2020 and February 2022. Patients were divided according to their maximum COVID-19 WHO ordinal severity score (WHO 0–10) into hospitalized patients with a non-severe course of disease (WHO 4–5, n = 52) and those with a severe course of disease (WHO 6–10, n = 75). Non-infected individuals served as healthy controls (WHO 0, n = 42). Blood was analyzed with respect to cell numbers, clotting factors, as well as pro- and anti-inflammatory mediators in plasma. As functional parameters, phagocytosis and inflammatory responses to LPS and antigen-specific stimulation were determined in monocytes, granulocytes, and T cells using flow cytometry. Findings: In the present study, immune and coagulation systems were analyzed simultaneously. Interestingly, many severe COVID-19 patients showed an upregulation of pro-inflammatory mediators and at the same time clear signs of immunosuppression. Furthermore, severe COVID-19 patients not only exhibited a disturbed immune system, but in addition showed a pronounced pro-coagulation phenotype with impaired fibrinolysis. Therefore, our study adds another puzzle piece to the already complex picture of COVID-19 pathology implying that therapies in COVID-19 must be individualized. Conclusion: Despite years of research, COVID-19 has not been understood completely and still no therapies exist, fitting all requirements and phases of COVID-19 disease. This observation is highly reminiscent to sepsis. Research in sepsis has been going on for decades, while the disease is still not completely understood and therapies fitting all patients are lacking as well. In both septic and COVID-19 patients, immune activation can be accompanied by immune paralysis, complicating therapeutic intervention. Accordingly, therapies that lower immune activation may cause detrimental effects in patients, who are immune paralyzed by viral infections or sepsis. We therefore suggest individualizing therapies and to broaden the spectrum of immunological parameters analyzed before therapy. Only if the immune status of a patient is understood, can a therapeutic intervention be successful.

Aspergillus spp. are widespread environmental pathogens that can induce invasive aspergillosis, especially in immunocompromised patients. An 86-year-old female patient presented with a rare case of invasive cerebral aspergillosis. The aspergilloma invaded the intracranial region originating from the ethmoidal sinus and the orbital apex. In contrast to routine diagnostic procedures, next-generation sequencing (NGS) was able to identify the fungal pathogen in the cerebrospinal fluid as well as in plasma samples, supporting the biopsy-based diagnosis of invasive cerebral aspergillosis. Therefore, NGS-based diagnostics may be of particular importance for difficult-to-diagnose disease states, when conventional diagnostic procedures fail.