Stewardship: it's going viral.

Introduction: Historically, antimicrobial stewardship (AMS) has considered the judicious use of antibiotics. AMS is widely adopted across Europe and the US; recently antifungal AMS is gaining momentum but antiviral AMS has been little described. Here we describe the introduction of AMS virology reviews at University Hospitals Birmingham (UHBFT); a novel concept and an opportunity to broaden the beneficial aspects of AMS to virology, termed anti-viral stewardship (AVS). Method: In June 2022, a UK supply issue with aciclovir injection (ACV IV) was announced. In order to review and preserve parenteral ACV for those in greatest need, UHBFT pharmacist and virologists implemented a specialist review for patients prescribed more than 48 hours of treatment. This review initially lasted 10 weeks and data was collected on the advice offered, whether it was accepted, and time required completing the review. Results: AVS rounds halved IV ACV consumption, compared to pre or post intervention levels, with more than half of patients advised to stop or switch to oral therapy. Diagnostics and sampling guidance was offered in one quarter of reviews, whilst the remaining interventions were more stewardship focused. In almost all cases stewardship advice was readily accepted by clinical teams. Due to positive feedback from clinicians and its effective management of supply, the anti-viral stewardship (AVS) programme was re-introduced in June 2023. Conclusions: Antiviral AMS rounds provide an opportunity to optimise sampling, diagnosis and improve patient management. Introduction of regular AVS at UHBFT are now well established and plan to be implemented in other hospitals.

Monkeypox: An old foe, with new challenges.

At first glance, a multi-country outbreak of monkeypox in 2022 seems unusual. However, the re-emergence and expansion of this viral disease beyond its endemicity in West and Central Africa had previously been predicted as a possible consequence of a decline in population immunity following smallpox eradication. Since the 13th of May 2022, cases of monkeypox have been reported in at least 28 WHO member states from within 4 regions (the Americans, European, Eastern Mediterranean and Western Pacific regions). This summary describes the multi-country outbreak to date, with an emphasis on patient demographics, common symptoms and signs, clinical management (including infection prevention measures) and clinical outcomes of the cases in the United Kingdom, which has so far reported the largest number of laboratory confirmed cases. The future implications of this outbreak, including preventative measures to curb the current outbreak, prevent future outbreaks and the likelihood of the disease becoming endemic in the UK are also discussed.

How and when to use CSF to investigate neonates and children with possible central nervous system infection.

A child presented to the emergency department with fever, reduced consciousness, irritability and reduced oral intake. Infective meningitis and encephalitis were within the differential diagnoses. Is a lumbar puncture (LP) indicated and, if so, what is the optimal timing of LP? Will antimicrobial pretreatment affect the cerebrospinal fluid (CSF) results? How can clinicians optimise diagnostic stewardship to benefit individual patients and society at large? Interpretation of rapidly available CSF biochemical tests (protein, glucose and lactate levels) and microscopy can provide a prompt insight into the infective aetiology and inform treatment and further diagnostic testing strategies. Diagnosis of an aetiological pathogen in a patient presenting with central nervous system (CNS) infection has clinical, infection control and public health implications. A plethora of tests are available to enable CSF analysis in patients with possible CNS infection. We aimed to summarise current evidence and guidance to ensure the best possible use of the diagnostics available.

An experience using historical hepatitis C data to Re-Engage: Possibilities and pitfalls during the COVID-19 pandemic.

OBJECTIVES: Public Health England (PHE) aims meet the WHO target to eliminate hepatitis C as a public health concern by 2030. One aspect of this strategy is to use historical surveillance data of anti-HCV positive patients identified by PHE to re-engage with offers of PCR testing and treatment if RNA-positive. Operational Delivery Networks (ODN), who deliver Hepatitis C treatment across 22 regions in England, are responsible for enacting this initiative. This study aims to evaluate the effectiveness of using this data with regional PCR results to re-engage HCV-infected persons in the West Midlands region of England. STUDY DESIGN: A longitudinal prospective study using historical surveillance data. METHODS: A dataset of historical anti-HCV positive antibody patients provided to the ODN by PHE was cross-referenced with HCV RNA data from 01/01/1996 to 01/01/2019 from five laboratories across the West Midlands. Letters were sent to the general practitioner and to the patients who were HCV RNA positive to invite them for repeat testing and treatment to achieve cure. RESULTS: From a dataset of 4540 anti-HCV antibody results, 31.7% (n=1440) had a PCR result: 48.1% (n=693) were PCR positive for HCV RNA. 693 letters were sent to GPs with responses from 14.2% (n=99). By May 2021, only 212 patient letters were sent (due to significant interruption by the COVID-19 pandemic) and 11.3% (n=24) replied, 17 presented for PCR testing and 4 were found to be viraemic. To date, one patient has achieved cure and three have completed treatment awaiting confirmation of cure. CONCLUSION: The use of historical anti-HCV antibody results can be used to successfully re-engage people into testing and treatment for hepatitis C, albeit with modest gains.

S-Variant SARS-CoV-2 Lineage B1.1.7 Is Associated With Significantly Higher Viral Load in Samples Tested by TaqPath Polymerase Chain Reaction.

A SARS-CoV-2 variant B1.1.7 containing mutation Δ69/70 has spread rapidly in the United Kingdom and shows an identifiable profile in ThermoFisher TaqPath RT-qPCR, S gene target failure (SGTF). We analyzed recent test data for trends and significance. Linked cycle threshold (Ct) values for respiratory samples showed that a low Ct for ORF1ab and N were clearly associated with SGTF. Significantly more SGTF samples had higher inferred viral loads between 1×107 and 1×108. Our conclusion is that patients whose samples exhibit the SGTF profile are more likely to have high viral loads, which may explain higher infectivity and rapidity of spread.

Dried blood spot and mini-tube blood sample collection kits for postal HIV testing services: a comparative review of successes in a real-world setting.

OBJECTIVES: This is a comparative review between using dried blood spot (DBS) and mini-tube (MT) HIV sampling kits as part of an online sexually transmitted infection (STI) postal testing service. England has recently seen increases in internet-based and postal (eHealth) STI services. Expanding accessibility and testing for patients, cost implications and narrowing the HIV undiagnosed margin are drivers for this. METHODS: In 2017, data were reviewed from an online postal STI kit requesting service at a time of transitioning from MT to DBS. We compared the STI postal kit and HIV blood sample return rates, and the successful processing/analysis rates of the DBS and MT kits. Descriptive statistics were applied to participant characteristics, with Pearson's χ2 or Fisher exact test used to demonstrate statistical differences. We also describe and calculate a 'request-to-result ratio' (RRR) for both kit types. The RRR is defined as the number of online kit requests required to produce one successfully analysed result. RESULTS: 550 STI postal kit requests from a North-West of England region were reviewed from 13 June 2017 to 22 September 2017 (275 MT, 275 DBS). Baseline characteristics between the two groups were comparable (63% woman, 90% white British and 86% heterosexual with a median age of 26 years). The successful processing rate for the DBS was 98.8% c.f. 55.7% for the MT (p<0.001). The RRR for MT was 2.96, c.f. 1.70 for DBS. There was a 5.4% false positive HIV rate in the MT c.f. none in the DBS. CONCLUSIONS: This comparative analysis suggests that in this community setting, the use of postal HIV DBS kits resulted in a significantly improved RRR compared with MT. The biggest factor was the large number of MT samples not analysed due to inadequate blood volumes. The unexpected level of false positive results in the MT samples needs confirming in larger studies.

Seroprevalence of maternal HIV, hepatitis B, and syphilis in a major maternity hospital in North Kordofan, Sudan.

Routine infectious diseases screening of Sudanese pregnant women has been patchy due to scarcity of healthcare resources and social stigma. We sought to determine the seroprevalence of HIV, hepatitis B, and syphilis among pregnant women attending antenatal care (ANC) at El Obeid Maternity Hospital in western Sudan. We also explored the association between these infections and a set of socio-demographic and maternal variables. Unlinked anonymous testing for HIV-1/2 antibodies, hepatitis B surface antigen, and Treponema pallidum antibodies was performed on residual blood samples collected during routine ANC (August 2016-March 2017). Seroprevalence of HIV was 1.13% (5/444; 95% CI 0.37-2.61%), hepatitis B 2.93% (13/444; 95% CI 1.57-4.95%), and syphilis 7.43% (33/444; 95% CI 5.17-10.28%). On bivariate analysis, there were no statistically significant associations between hepatitis B, syphilis, or a composite outcome including any of the three infections and age, stage of pregnancy, gravidity, parity, previous mode of delivery, history of blood transfusion, or husband polygamy. Urgent action is needed to scale up routine maternal screening for HIV, hepatitis B, and syphilis on an opt-out basis. Further research into the socio-demographic and behavioural determinants of these infections as well as their clinical outcomes is needed.

Active screening and surveillance in the United Kingdom for Middle East respiratory syndrome coronavirus in returning travellers and pilgrims from the Middle East: a prospective descriptive study for the period 2013-2015.

BACKGROUND: Over 25000 pilgrims from the UK visit Saudi Arabia every year for the Umrah and Hajj pilgrimages. The recent outbreak of Middle East respiratory syndrome coronavirus (MERS-CoV) in South Korea and the continuing reports of MERS-CoV cases from Saudi Arabia highlight the need for active surveillance for MERS-CoV in returning pilgrims or travellers from the Middle East. Public Health England Birmingham Laboratory (PHEBL) is one of a few selected UK public health laboratories responsible for MERS-CoV screening in travellers returning to the UK from the Middle East who present to hospital with severe respiratory symptoms. The results of the PHEBL MERS-CoV screening and surveillance over the past 3 years is presented. METHODS: UK travellers/pilgrims who returned from the Middle East and presented to a hospital with respiratory symptoms were studied over the period February 1, 2013 to December 31, 2015. Patients with respiratory symptoms, who satisfied the Public Health England MERS-CoV case algorithm, were tested for MERS-CoV and other respiratory tract viruses on admission to hospital. RESULTS: Two hundred and two patients suspected of having MERS-CoV were tested. None of them had a laboratory-confirmed MERS-CoV infection. A viral aetiology was detected in half (50.3%) of the cases, with rhinoviruses, influenza A (H1N1 and H3N2), and influenza B being most frequent. Peak testing occurred following the annual Hajj season and in other periods of raised national awareness. CONCLUSIONS: Respiratory tract infections in travellers/pilgrims returning to the UK from the Middle East are mainly due to rhinoviruses, influenza A, and influenza B. Whilst MERS-CoV was not detected in the 202 patients studied, heightened awareness of the possibility of MERS-CoV and continuous proactive surveillance are essential to rapidly identify cases of MERS-CoV and other seasonal respiratory tract viruses such as avian influenza, in patients presenting to hospital. Early identification and isolation may prevent outbreaks in nosocomial settings.

CD25+ natural regulatory T cells are critical in limiting innate and adaptive immunity and resolving disease following respiratory syncytial virus infection.

Regulatory CD4(+) T cells have been shown to be important in limiting immune responses, but their role in respiratory viral infections has received little attention. Here we observed that following respiratory syncytial virus (RSV) infection, CD4(+) Foxp3(+) CD25(+) natural regulatory T-cell numbers increased in the bronchoalveolar lavage fluid, lung, mediastinal lymph nodes, and spleen. The depletion of CD25(+) natural regulatory T cells prior to RSV infection led to enhanced weight loss with delayed recovery that was surprisingly accompanied by increased numbers of activated natural killer cells in the lung and bronchoalveolar lavage fluid on day 8 postinfection. Increased numbers of neutrophils were also detected within the bronchoalveolar lavage fluid and correlated with elevated levels of myeloperoxidase as well as interleukin-6 (IL-6) and gamma interferon (IFN-gamma). CD25(+) natural regulatory T-cell depletion also led to enhanced numbers of proinflammatory T cells producing IFN-gamma and tumor necrosis factor alpha (TNF-alpha) in the lung. Despite these increases in inflammatory responses and disease severity, the viral load was unaltered. This work highlights a critical role for natural regulatory T cells in regulating the adaptive and innate immune responses during the later stages of lung viral infections.

A case for varicella vaccination in the immunosuppressed.

A middle-aged man with long-standing Crohn disease maintained in remission on low-dose immunosuppression presented with abdominal pain. Over the following few days he developed a vesicular rash, became dyspnoeic, confused and had two seizures. Despite high-dose intravenous aciclovir, he died. Disseminated varicella zoster virus, the cause of his death, could potentially have been prevented had he received varicella vaccination at an earlier stage.

Immune activation and IL-12 production during acute/early HIV infection in the absence and presence of highly active, antiretroviral therapy.

Suppressed IL-12 production and maladaptive immune activation, both of which are ameliorated by successful highly active antiretroviral therapy (HAART), are thought to play important roles in the immunopathogenesis of chronic HIV infection. Despite the important effects of the immunological and virological events of early HIV infection on subsequent disease progression, IL-12 production and immune activation in early infection remain under-defined. To quantify IL-12 production and immune activation during acute/early HIV infection, in the presence and absence of HAART, we performed a prospective, longitudinal study of participants in the Baltimore site of the Acute Infection and Early Disease Research Program, with cross-sectional comparison to healthy control subjects. PBMC cytokine productive capacity and plasma immune activation markers [soluble CD8 (sCD8), sCD4, granzyme B, neopterin, beta2-microglobulin, sIL-2R, sTNFRI, sTNFRII, and IL-12p70] were quantified by ELISA. Notably, PBMC from patients with acute/early HIV infection exhibited in vivo IL-12p70 production along with increased, maximal in vitro IL-12 production. Further, despite evidence from plasma markers of generalized immune activation, no elevation in plasma levels of sCD4 was observed, suggesting relative blunting of in vivo CD4+ T cell activation from the beginning of HIV infection. Finally, despite successful virological responses to HAART, heightened in vivo CD8+ T cell activation, IL-12 production, and IFN activity were sustained for at least 6 months during primary HIV infection. These data underscore the need for comparative mechanistic analysis of the immunobiology of early and chronic HIV infection.

Inhibition of TLR-4/MD-2 signaling by RP105/MD-1.

Activation of Toll-like receptor (TLR) signaling by microbial and host molecular signatures is critical to the induction of immune responses. Such signaling is, perforce, kept under tight control. We recently discovered a novel endogenous inhibitor of TLR-4 - RP105. Initially identified as a B-cell-specific molecule with a role in B-cell proliferation in response to RP105 mAb and LPS, RP105 is a TLR-4 homologue. Further, like TLR-4 whose surface expression and signaling depends upon co-expression of the secreted protein MD-2, surface expression of RP105 is dependent upon co-expression of the MD2 homologue, MD-1. Unlike the TLRs, however, RP105 lacks a signaling domain, having the apparent structure of a TLR inhibitor. Further, RP105 is not B-cell-specific; its expression directly mirrors that of TLR-4 on dendritic cells and macrophages. These considerations suggested a role for RP105 as a physiological inhibitor of TLR-4 signaling. Indeed, we have recently found that: (i) RP105 is a specific inhibitor of TLR-4 signaling in HEK293 cells; (ii) RP105/MD-1 interacts directly with TLR-4/MD-2, inhibiting the ability of this signaling complex to bind LPS; (iii) RP105 regulates TLR-4 signaling in dendritic cells and macrophages; and (iv) RP105 regulates in vivo responses to LPS.

Association of CTLA4 polymorphism with regulatory T cell frequency.

A common single nucleotide polymorphism in CTLA4 has been linked with susceptibility and outcome in autoimmune and infectious diseases, respectively. Here, we show that this polymorphism is associated with the frequency of CD4(+)CD25(+) regulatory T cells in healthy human volunteers. We further show that, on a per cell basis, such regulatory T cells appear to be functionally indistinguishable across CTLA4 genotypes. These data implicate CTLA4 in regulatory T cell development, and provide a mechanism to account for the link between polymorphisms at this locus and the biological outcome of adaptive immune responses to self and to pathogens.

Negative regulation of Toll-like receptor 4 signaling by the Toll-like receptor homolog RP105.

Activation of Toll-like receptor (TLR) signaling by microbial signatures is critical to the induction of immune responses. Such responses demand tight regulation. RP105 is a TLR homolog thought to be mostly B cell specific, lacking a signaling domain. We report here that RP105 expression was wide, directly mirroring that of TLR4 on antigen-presenting cells. Moreover, RP105 was a specific inhibitor of TLR4 signaling in HEK 293 cells, a function conferred by its extracellular domain. Notably, RP105 and its helper molecule, MD-1, interacted directly with the TLR4 signaling complex, inhibiting its ability to bind microbial ligand. Finally, RP105 regulated TLR4 signaling in dendritic cells as well as endotoxin responses in vivo. Thus, our results identify RP105 as a physiological negative regulator of TLR4 responses.

Defective lipoxin-mediated anti-inflammatory activity in the cystic fibrosis airway.

In cystic fibrosis, dysregulated neutrophilic inflammation and chronic infection lead to progressive destruction of the airways. The underlying mechanisms have remained unclear. Lipoxins are anti-inflammatory lipid mediators that modulate neutrophilic inflammation. We report here that lipoxin concentrations in airway fluid were significantly suppressed in patients with cystic fibrosis compared to patients with other inflammatory lung conditions. We also show that administration of a metabolically stable lipoxin analog in a mouse model of the chronic airway inflammation and infection associated with cystic fibrosis suppressed neutrophilic inflammation, decreased pulmonary bacterial burden and attenuated disease severity. These findings suggest that there is a pathophysiologically important defect in lipoxin-mediated anti-inflammatory activity in the cystic fibrosis lung and that lipoxins have therapeutic potential in this lethal autosomal disease.