Severe Tick-Borne Encephalitis (TBE) in a Patient with X-Linked Agammaglobulinemia; Treatment with TBE Virus IgG Positive Plasma, Clinical Outcome and T Cell Responses

PURPOSE

A patient with X-linked agammaglobulinemia (XLA) and severe tick-borne encephalitis (TBE) was treated with TBE virus (TBEV) IgG positive plasma. The patient's clinical response, humoral and cellular immune responses were characterized pre- and post-infection.

METHODS

ELISA and neutralisation assays were performed on sera and TBEV PCR assay on sera and cerebrospinal fluid. T cell assays were conducted on peripheral blood the patient and five healthy vaccinated controls.

RESULTS

The patient was admitted to the hospital with headache and fever. He was not vaccinated against TBE but receiving subcutaneous IgG-replacement therapy (IGRT). TBEV IgG antibodies were low-level positive (due to scIGRT), but the TBEV IgM and TBEV neutralisation tests were negative. During hospitalisation his clinical condition deteriorated (Glasgow coma scale 3/15) and he was treated in the ICU with corticosteroids and external ventricular drainage. He was then treated with plasma containing TBEV IgG without apparent side effects. His symptoms improved within a few days and the TBEV neutralisation test converted to positive. Robust CD8+ T cell responses were observed at three and 18-months post-infection, in the absence of B cells. This was confirmed by tetramers specific for TBEV.

CONCLUSION

TBEV IgG-positive plasma given to an XLA patient with TBE without evident adverse reactions may have contributed to a positive clinical outcome. Similar approaches could offer a promising foundation for researching therapeutic options for patients with humoral immunodeficiencies. Importantly, a robust CD8+ T cell response was observed after infection despite the lack of B cells and indicates that these patients can clear acute viral infections and could benefit from future vaccination programs.

Changes in trauma-related emergency medical services during the COVID-19 lockdown in the Western Cape, South Africa

BACKGROUND

To limit virus spread during the COVID pandemic, extensive measures were implemented around the world. In South Africa, these restrictions included alcohol and movement restrictions, factors previously linked to injury burden in the country. Consequently, reports from many countries, including South Africa, have shown a reduction in trauma presentations related to these restrictions. However, only few studies and none from Africa focus on the impact of the pandemic restrictions on the Emergency Medical System (EMS).

METHODS

We present a retrospective, observational longitudinal study including data from all ambulance transports of physical trauma cases collected during the period 2019-01-01 and 2021-02-28 from the Western Cape Government EMS in the Western Cape Province, South Africa (87,167 cases). Within this timeframe, the 35-days strictest lockdown level period was compared to a 35-days period prior to the lockdown and to the same 35-days period in 2019. Injury characteristics (intent, mechanism, and severity) and time were studied in detail. Ambulance transport volumes as well as ambulance response and on-scene time before and during the pandemic were compared. Significance between indicated periods was determined using Chi-square test.

RESULTS

During the strictest lockdown period, presentations of trauma cases declined by > 50%. Ambulance transport volumes decreased for all injury mechanisms and proportions changed. The share of assaults and traffic injuries decreased by 6% and 8%, respectively, while accidental injuries increased by 5%. The proportion of self-inflicted injuries increased by 5%. Studies of injury time showed an increased share of injuries during day shift and a reduction of total injury volume during the weekend during the lockdown. Median response- and on-scene time remained stable in the time-periods studied.

CONCLUSION

This is one of the first reports on the influence of COVID-19 related restrictions on EMS, and the first in South Africa. We report a decline in trauma related ambulance transport volumes in the Western Cape Province as well as changes in injury patterns, largely corresponding to previous findings from hospital settings in South Africa. The unchanged response and on-scene times indicate a well-functioning EMS despite pandemic challenges. More studies are needed, especially disaggregating the different restrictions.

High Prevalence of SARS-CoV-2 Omicron Infection Despite High Seroprevalence, Sweden, 2022

We performed 2 surveys during 2022 to estimate point prevalences of SARS-CoV-2 infection compared with overall viral seroprevalence in Sweden. Point prevalence was 1.4% in March and 1.5% in September. Estimated seroprevalence was >80%, including among unvaccinated children. Continued SARS-CoV-2 surveillance is necessary for detecting emerging, possibly more pathogenic variants.

Ten-Week Follow-Up of Monkeypox Case-Patient, Sweden, 2022

A previously healthy male patient had detectable monkeypox virus DNA in saliva 76 days after laboratory confirmation of infection. A comprehensive characterization of viral kinetics and a detailed follow-up indicated a declining risk for transmission during the weeks after monkeypox symptoms appeared.

Long-term SARS-CoV-2-specific and cross-reactive cellular immune responses correlate with humoral responses, disease severity, and symptomatology

Background

Cellular immune memory responses post coronavirus disease 2019 (COVID‐19) have been difficult to assess due to the risks of contaminating the immune response readout with memory responses stemming from previous exposure to endemic coronaviruses. The work herein presents a large‐scale long‐term follow‐up study investigating the correlation between symptomology and cellular immune responses four to five months post seroconversion based on a unique severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2)‐specific peptide pool that contains no overlapping peptides with endemic human coronaviruses.

Methods

Peptide stimulated memory T cell responses were assessed with dual interferon‐gamma (IFNγ) and interleukin (IL)‐2 Fluorospot. Serological analyses were performed using a multiplex antigen bead array.

Results

Our work demonstrates that long‐term SARS‐CoV‐2‐specific memory T cell responses feature dual IFNγ and IL‐2 responses, whereas cross‐reactive memory T cell responses primarily generate IFNγ in response to SARS‐CoV‐2 peptide stimulation. T cell responses correlated to long‐term humoral immune responses. Disease severity as well as specific COVID‐19 symptoms correlated with the magnitude of the SARS‐CoV‐2‐specific memory T cell response four to five months post seroconversion.

Conclusion

Using a large cohort and a SARS‐CoV‐2‐specific peptide pool we were able to substantiate that initial disease severity and symptoms correlate with the magnitude of the SARS‐CoV‐2‐specific memory T cell responses.

A phenomics approach for antiviral drug discovery

BACKGROUND

The emergence and continued global spread of the current COVID-19 pandemic has highlighted the need for methods to identify novel or repurposed therapeutic drugs in a fast and effective way. Despite the availability of methods for the discovery of antiviral drugs, the majority tend to focus on the effects of such drugs on a given virus, its constituent proteins, or enzymatic activity, often neglecting the consequences on host cells. This may lead to partial assessment of the efficacy of the tested anti-viral compounds, as potential toxicity impacting the overall physiology of host cells may mask the effects of both viral infection and drug candidates. Here we present a method able to assess the general health of host cells based on morphological profiling, for untargeted phenotypic drug screening against viral infections.

RESULTS

We combine Cell Painting with antibody-based detection of viral infection in a single assay. We designed an image analysis pipeline for segmentation and classification of virus-infected and non-infected cells, followed by extraction of morphological properties. We show that this methodology can successfully capture virus-induced phenotypic signatures of MRC-5 human lung fibroblasts infected with human coronavirus 229E (CoV-229E). Moreover, we demonstrate that our method can be used in phenotypic drug screening using a panel of nine host- and virus-targeting antivirals. Treatment with effective antiviral compounds reversed the morphological profile of the host cells towards a non-infected state.

CONCLUSIONS

The phenomics approach presented here, which makes use of a modified Cell Painting protocol by incorporating an anti-virus antibody stain, can be used for the unbiased morphological profiling of virus infection on host cells. The method can identify antiviral reference compounds, as well as novel antivirals, demonstrating its suitability to be implemented as a strategy for antiviral drug repurposing and drug discovery.

Targeting OGG1 arrests cancer cell proliferation by inducing replication stress

Altered oncogene expression in cancer cells causes loss of redox homeostasis resulting in oxidative DNA damage, e.g. 8-oxoguanine (8-oxoG), repaired by base excision repair (BER). PARP1 coordinates BER and relies on the upstream 8-oxoguanine-DNA glycosylase (OGG1) to recognise and excise 8-oxoG. Here we hypothesize that OGG1 may represent an attractive target to exploit reactive oxygen species (ROS) elevation in cancer. Although OGG1 depletion is well tolerated in non-transformed cells, we report here that OGG1 depletion obstructs A3 T-cell lymphoblastic acute leukemia growth in vitro and in vivo, validating OGG1 as a potential anti-cancer target. In line with this hypothesis, we show that OGG1 inhibitors (OGG1i) target a wide range of cancer cells, with a favourable therapeutic index compared to non-transformed cells. Mechanistically, OGG1i and shRNA depletion cause S-phase DNA damage, replication stress and proliferation arrest or cell death, representing a novel mechanistic approach to target cancer. This study adds OGG1 to the list of BER factors, e.g. PARP1, as potential targets for cancer treatment.

Novel Broad-Spectrum Antiviral Inhibitors Targeting Host Factors Essential for Replication of Pathogenic RNA Viruses

Recent RNA virus outbreaks such as Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and Ebola virus (EBOV) have caused worldwide health emergencies highlighting the urgent need for new antiviral strategies. Targeting host cell pathways supporting viral replication is an attractive approach for development of antiviral compounds, especially with new, unexplored viruses where knowledge of virus biology is limited. Here, we present a strategy to identify host-targeted small molecule inhibitors using an image-based phenotypic antiviral screening assay followed by extensive target identification efforts revealing altered cellular pathways upon antiviral compound treatment. The newly discovered antiviral compounds showed broad-range antiviral activity against pathogenic RNA viruses such as SARS-CoV-2, EBOV and Crimean-Congo hemorrhagic fever virus (CCHFV). Target identification of the antiviral compounds by thermal protein profiling revealed major effects on proteostasis pathways and disturbance in interactions between cellular HSP70 complex and viral proteins, illustrating the supportive role of HSP70 on many RNA viruses across virus families. Collectively, this strategy identifies new small molecule inhibitors with broad antiviral activity against pathogenic RNA viruses, but also uncovers novel virus biology urgently needed for design of new antiviral therapies.

Durable control of hepatitis C through interferon-free antiviral combination therapy immediately prior to allogeneic haematopoietic stem cell transplantation

Chronic hepatitis C virus (HCV) infection carries increased risks for morbidity and mortality in patients undergoing allogeneic haematopoietic stem cell transplantation (HSCT) but has become curable through the advent of directly acting antiviral compounds. Current guidelines of the American Society for Blood and Marrow Transplantation (ASBMT) recommend that HCV-infected HSCT candidates preferably start and complete therapy prior to transplant. However, this is often not feasible due to time constraints or treatment-limiting comorbidities, conditions and treatments. For these reasons, data on the safety of antiviral treatment, its efficacy to achieve durable eradication of the virus until full immune recovery, and late effects of former HCV infection in patients receiving HSCT are unknown. Here, we report the course of two paediatric patients with chronic HCV infection who received a full course of directly acting antivirals prior to allogeneic HSCT and achieved and maintained viral eradication throughout transplantation until complete immune recovery.

Evaluation of a Stenotrophomonas maltophilia bacteremia cluster in hematopoietic stem cell transplantation recipients using whole genome sequencing

Background

Stenotrophomonas maltophilia ubiquitously occurs in the hospital environment. This opportunistic pathogen can cause severe infections in immunocompromised hosts such as hematopoietic stem cell transplantation (HSCT) recipients. Between February and July 2016, a cluster of four patients on the HSCT unit suffered from S. maltophilia bloodstream infections (BSI).

Methods

For epidemiological investigation we retrospectively identified the colonization status of patients admitted to the ward during this time period and performed environmental monitoring of shower heads, shower outlets, washbasins and toilets in patient rooms. We tested antibiotic susceptibility of detected S. maltophilia isolates. Environmental and blood culture samples were subjected to whole genome sequence (WGS)-based typing.

Results

Of four patients with S. maltophlilia BSI, three were found to be colonized previously. In addition, retrospective investigations revealed two patients being colonized in anal swab samples but not infected. Environmental monitoring revealed one shower outlet contaminated with S. maltophilia. Antibiotic susceptibility testing of seven S. maltophlia strains resulted in two trimethoprim/sulfamethoxazole resistant and five susceptible isolates, however, not excluding an outbreak scenario. WGS-based typing did not result in any close genotypic relationship among the patients' isolates. In contrast, one environmental isolate from a shower outlet was closely related to a single patient's isolate.

Conclusion

WGS-based typing successfully refuted an outbreak of S. maltophilia on a HSCT ward but uncoverd that sanitary installations can be an actual source of S. maltophilia transmissions.

Norovirus infections in a tertiary care centre - individual cases do not necessarily lead to an outbreak

BACKGROUND

Norovirus is responsible for the majority of gastroenteritis outbreaks within healthcare settings. Routes of spread include foodborne-, waterborne- and especially person-to-person transmissions.

OBJECTIVE

We investigated the overall attack rate of norovirus, within and outside outbreak situations, transmitted via patient-to-patient contact in a tertiary care centre from January 2012 to March 2015.

STUDY DESIGN

We monitored exposed asymptomatic patients next to infectious patients for the development of symptoms of acute gastroenteritis following exposure.

RESULTS

We detected 102 patients with contact to 94 infectious patients. Of these only 11 patients developed typical norovirus symptoms after exposure while 91 patients remained asymptomatic. Total secondary attack rate was only 10.8%.

CONCLUSIONS

Patient-to-patient transmission of norovirus is potentially overestimated within clinical settings. Future prevention strategies should consider personal risk factors of exposed patients.