Exposure and virologic outcomes of dolutegravir combined with ritonavir boosted darunavir in treatment-naïve individuals enrolled in the Netherlands Cohort Study on Acute HIV infection (NOVA).

To the authors' knowledge, there is currently no literature or guidance recommendation regarding whether the dose of dolutegravir (DTG) should be increased when co-administered with darunavir/ritonavir (DRV/r) in patients with acute human immunodeficiency virus infection (AHI). This study assessed the pharmacokinetics (PK) of twice-daily (BID) DTG and once-daily (QD) DRV/r, and compared this with DTG QD without DRV/r in patients with AHI. Forty-six participants initiated antiretroviral therapy within <24 h of enrolment: DTG 50 mg BID, DRV/r 800/100 mg QD, and two nucleoside reverse transcriptase inhibitors (NRTIs) for 4 weeks (Phase I); and DTG 50 mg QD with two NRTIs thereafter (Phase II: reference). Total DTG trough concentration (Ctrough) and area under the concentration-time profile of 0-24 h (AUC0-24h) were predicted using a population PK model. DTG glucuronidation metabolic ratio (MR) and DTG free fraction were determined and compared per treatment phase using geometric mean ratio (GMR) and 90% confidence interval (CI). Participants had a predicted geometric mean steady-state DTG Ctrough of 2.83 [coefficient of variation (CV%) 30.3%] mg/L (Phase I) and 1.28 (CV% 52.4%) mg/L (Phase II), with GMR of 2.20 (90% CI 1.90-2.55). Total exposure during DTG BID increased but did not double [AUC0-24h GMR 1.65 (90% CI 1.50-1.81) h.mg/L]. DTG glucuronidation MR increased by approximately 29% during Phase I. DTG Ctrough was above in-vivo EC90 (0.32 mg/L) during both phases, except in one participant during Phase I. At Week 8, 84% of participants had viral loads ≤40 copies/mL. The drug-drug interaction between DTG (BID) and DRV/r (QD) was due to induced glucuronidation, and is not clinically relevant in patients with AHI.

Current evidence on the adoption of indicator condition guided testing for HIV in western countries: A systematic review and meta-analysis.

BACKGROUND: Indicator condition (IC) guided testing for HIV is an effective way to identify undiagnosed people living with HIV, but studies suggest its implementation is lacking. This systematic review provides an overview of the adoption of IC-guided testing in Western countries. METHODS: Seven ICs were selected: tuberculosis (TB), malignant lymphoma, hepatitis B, hepatitis C, cervical/vulvar carcinoma/intraepithelial neoplasia grade 2+ (CC/CIN2+, VC/VIN2+), and peripheral neuropathy (PN). Embase and Ovid MEDLINE were searched up to November 20th, 2020. Publications of all types, using data from ≥2009, reporting on HIV test ratios in patients ≥18 years in all settings in Western countries were eligible. HIV test ratios and positivity were reported per IC. A random effects-model for proportions was used to calculate estimated proportions (ES) with 95% CIs. This study was registered at PROSPERO, registration number CRD42020160243. FINDINGS: Fifty-seven references, including 23 full-text articles and 34 other publications were included. Most (28/57) reported on HIV testing in TB. No reports on HIV testing in VC/VIN2+ or PN patients were eligible for inclusion. Large variation in HIV test ratios was observed between and within ICs, resulting from different testing approaches. Highest HIV test ratios (pooled ratio: 0·72, 95%CI 0·63-0·80) and positivity (0·05, 95% CI 0·03-0·06) were observed among TB patients, and lowest among CC/CIN2+ patients (pooled ES test ratio: 0·12, 95%CI 0·01-0·31, positivity: 0·00, 95%CI 0·00-0·00). INTERPRETATION: IC-guided HIV testing is insufficiently implemented in Western countries. The large variation in test ratios provides insight into priority areas for implementing routine IC-guided HIV testing in the future. FUNDING: HIV Transmission Elimination in Amsterdam (H-TEAM) consortium and Aidsfonds (grant number P-42,702).

COVA1-18 neutralizing antibody protects against SARS-CoV-2 in three preclinical models.

One year into the Coronavirus Disease 2019 (COVID-19) pandemic caused by Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2), effective treatments are still needed 1-3 . Monoclonal antibodies, given alone or as part of a therapeutic cocktail, have shown promising results in patients, raising the hope that they could play an important role in preventing clinical deterioration in severely ill or in exposed, high risk individuals 4-6 . Here, we evaluated the prophylactic and therapeutic effect of COVA1-18 in vivo , a neutralizing antibody isolated from a convalescent patient 7 and highly potent against the B.1.1.7. isolate 8,9 . In both prophylactic and therapeutic settings, SARS-CoV-2 remained undetectable in the lungs of COVA1-18 treated hACE2 mice. Therapeutic treatment also caused a dramatic reduction in viral loads in the lungs of Syrian hamsters. When administered at 10 mg kg - 1 one day prior to a high dose SARS-CoV-2 challenge in cynomolgus macaques, COVA1-18 had a very strong antiviral activity in the upper respiratory compartments with an estimated reduction in viral infectivity of more than 95%, and prevented lymphopenia and extensive lung lesions. Modelling and experimental findings demonstrate that COVA1-18 has a strong antiviral activity in three different preclinical models and could be a valuable candidate for further clinical evaluation.

[Covid-19 reinfections: what is the clinical relevance?] / Re-infectie met SARS-CoV-2.

Every day additional confirmed case of SARS-CoV-2 reinfection are being reported across the globe. In the Netherlands more than 50 cases of probable reinfections have been identified. With more than 500 thousand people in the Netherlands who have been infected with SARS-CoV-2 up till now this number does seems to be quite low. Still, important questions have to be asked. How do we define reinfection and how do these reinfections compare to other (corona) viruses? What is the immunological significance? What is the duration of protective immunity? And what does Covid-19 reinfections mean for the prevention and development of a vaccine? The described cases of re-infections do teach us that a SARS-CoV-2 vaccine should also be considered for people with a documented Covid-19 infection in the past and that general precautions, such as the use of face masks and social distancing, still apply to those with a previous SARS-CoV-2 infection.

Increasing awareness and prompting HIV testing: Contributions of Amsterdam HIV Testing Week 2016.

We evaluated Amsterdam HIV Testing Week (HTW) 2016 regarding its primary goals of raising awareness and prompting HIV testing. Participating services offered free, anonymous HIV testing, with a focus on reaching men who have sex with men (MSM) and people with a non-western migration background. Sociodemographic characteristics, HIV testing history, intention to test regularly, beliefs about personal risk and severity of HIV, and perceived social norms regarding HIV testing and people living with HIV were assessed among all who tested. A community quick scan assessed awareness of Amsterdam HTW 2016 and attitudes and intentions regarding HIV testing. Of 806 people tested, 59.6% (405/679) belonged to key populations. None tested HIV-positive and 37.6% intended to test regularly in the future. The community quick scan found moderate awareness of Amsterdam HTW 2016. Awareness was highest among recent testers and HIV-positive MSM and not associated with HIV testing attitudes and intentions. People tested during Amsterdam HTW 2016 were from key populations and/or were not (adequately) reached via traditional testing approaches. The contribution of the Amsterdam HTW approach to raising awareness and prompting HIV testing in key populations may benefit from focusing on HIV-negative individuals who have not been tested recently.

17D yellow fever vaccine elicits comparable long-term immune responses in healthy individuals and immune-compromised patients.

BACKGROUND: The 17D live attenuated yellow fever (YF) vaccine is contra-indicated in immune-compromised individuals and may elicit a suboptimal immunologic response. The aim of this study is to assess whether long-term immune responses against the YF vaccine are impaired in immune-compromised patients. MATERIALS AND METHODS: Fifteen patients using different immunosuppressive drugs and 30 healthy individuals vaccinated 0-22 years ago were included. The serological response was measured using the plaque reduction neutralization test (PRNT). CD8(+) and CD4(+) T-cell responses were measured following proliferation and re-stimulation with YFV peptide pools. Phenotypic characteristics and cytokine responses of CD8(+) T-cells were determined using class I tetramers. RESULTS: The geometric mean titre of neutralizing antibodies was not different between the groups (p = 0.77). The presence of YFV-specific CD4(+) and CD8(+) T-cell did not differ between patients and healthy individuals (15/15, 100.0% vs. 29/30, 96.7%, p = 0.475). Time since vaccination correlated negatively with the number of YFV-specific CD8(+) T-cells (r = -0.66, p = 0.0045). Percentages of early-differentiated memory cells increased (r = 0.67, p = 0.017) over time. CONCLUSION: These results imply that YF vaccination is effective despite certain immunosuppressive drug regimens. An early-differentiated memory-like phenotype persisted, which is associated with effective expansion upon re-encounter with antigen, suggesting a potent memory T-cell pool remains.

Human Extraintestinal Sarcocystosis: What We Know, and What We don't Know.

There are over 150 known Sarcocystis species, and at least one is capable of infecting and causing disease in man. Extraintestinal (muscular) sarcocystosis and intestinal sarcocystosis are the two known manifestations of disease in humans. In this series of six cases and review, we focus on the invasive extraintestinal ("muscular") form of sarcocystosis in humans. This disease, which until recently was rarely described, has become relevant particularly as an imported condition in travelers due to a recent series of outbreaks reported from Malaysia. Human intestinal sarcocystosis is ubiquitous across the globe. However, absolute numbers of probable and particularly confirmed cases are few, with only several hundred described to date. Characteristically, patients exhibit signs and symptoms either 1-2 weeks after exposure, or after 4-8 weeks. Whether people remain asymptomatic or develop disease apparently depends on the infecting species, host factors, and the inoculum size. The definitive host(s) remain uncertain, and identification of the animal reservoir(s) requires further research. A better understanding of the epidemiology of the disease, as well as its immunological determinants, is hampered by the lack of reliable serological diagnostic methods. Additionally, DNA seems to be contained very effectively within the encysted parasite, thereby rendering PCR detection unreliable. Physicians should suspect the condition in patients with suggestive symptoms and a possible history of exposure. Surveillance networks for imported infectious diseases are formidable tools to help detect and localize outbreaks.

An underestimated lentivirus model: what can HIV-2 research contribute to the development of an effective HIV-1 vaccine?

The development of an HIV-1 vaccine that would be effective against all existing subtypes and circulating recombinant forms remains one of the great scientific and public health challenges of our generation. One of the major barriers to HIV-1 vaccine development is a lack of understanding of the correlates of protective immunity against the virus. In this context, research has focused on the rare phenomenon of spontaneous control of HIV-1 infection, in groups referred to as 'long-term nonprogressors' and 'elite controllers', together with models of nonprogressive sooty mangabey simian immunodeficiency (SIV) infection in African nonhuman primate hosts such as sooty mangabeys and African green monkeys, in which the majority of animals tolerate high levels of viral replication without development of immunodeficiency or disease. Much less attention has been given to humans infected with the nonpandemic strain HIV-2, derived from the SIV in West Africa, most of whom behave as long-term nonprogressors or viral controllers, while a minority develop disease clinically indistinguishable from AIDS caused by HIV-1. This apparent dichotomous outcome is, based on the evidence accumulated to date, more clearly related to the host immune response than the good clinical outcome of HIV-1 controllers. We propose that complementing research into HIV-1 controllers and nonpathogenic SIV models with the prioritization of HIV-2 research could enhance the HIV-1 vaccine research effort. The absence of disease progression or detectable plasma viral replication in the presence of an effective immune response in most patients living with HIV-2 represents an opportunity to unravel the virus' evolutionary adaptation in human hosts and to establish the correlates of such a protective response.

[Immunological defense to viral infections: focus on virus-specific T cells]. / Immunologische afweer tegen virale infecties: virusspecifieke T-cellen in beeld.

T cells play a central role in the control of and the protection against viral infections. The T cell population consists ofa diversity ofvirus-specific memory T cells. The characteristics of these T cells seem to depend largely on the type of virus for which they are specific. T cells directed against latent viruses, such as cytomegalovirus, are cytotoxic cells. T cells directed against viruses that after the initial infection are completely removed by the immune system, such as the influenza virus, are non-cytotoxic cells. The development of new immunological techniques, such as the detection of virus-specific cells with HLA-peptide tetrameric complexes, enables the characterization of the properties of virus-specific T cells in the blood and organs.

Main trajectories of nerves that traverse and surround the tympanic cavity in the rat.

To guide surgery of nerves that traverse and surround the tympanic cavity in the rat, anatomical illustrations are required that are topographically correct. In this study, maps of this area are presented, extending from the superior cervical ganglion to the otic ganglion. They were derived from observations that were made during dissections using a ventral approach. Major blood vessels, bones, transected muscles of the tongue and neck and supra and infrahyoid muscles serve as landmarks in the illustrations. The course of the mandibular, facial, glossopharyngeal, vagus, accessory and hypoglossal nerves with their branches, and components of the sympathetic system, are shown and discussed with reference to data available in the literature. Discrepancies in this literature can be clarified and new data are presented on the trajectories of several nerves. The course of the tympanic nerve was established. This nerve originates from the glossopharyngeal nerve, enters the tympanic cavity, crosses the promontory, passes the tensor tympani muscle dorsally, and continues its route intracranially to the otic ganglion as the lesser petrosal nerve after intersecting with the greater petrosal nerve. Auricular branches of the glossopharyngeal and of the vagus nerve were noted. We also observed a pterygopalatine branch of the internal carotid nerve, that penetrates the tympanic cavity and courses across the promontory.