#Hantavirus #stability and #inactivation

 

Abstract

Hantaviruses are zoonotic viruses that can cause highly pathogenic disease, including hantavirus cardiopulmonary syndrome (HCPS) and haemorrhagic fever with renal syndrome (HFRS), in humans with case-fatality rates of up to 50%. However, our understanding of the basic viral life cycle and the underlying causes of viral pathogenesis remains sparse, in large part due to a lack of molecular biology tools for hantaviruses and the need to work in high-containment laboratory facilities with these viruses. The stability and inactivation of hantavirus particles has been examined in some limited previous studies, however, a comprehensive, detailed and robust investigation of the stability of multiple hantaviruses has not been performed yet. Here, we investigated the kinetics of infectious Tula virus (TULV) particle production in Vero E6 cells and subsequent stability in cell culture media. In addition, we evaluated the stability of infectious virus particles in response to different physical and environmental stresses, including heat, freezing, dehydration and UV exposure, answering key questions about the environmental transmission potential of hantaviruses. Interestingly, we observed a remarkable stability of TULV when stored at room temperature or colder, as well as after dehydration, which suggests that hantaviruses could remain infectious for a sustained period of time after being secreted by their host species. Subsequently, we determined the ability of commonly used virus inactivation methods, including RNA and protein extraction buffers, to inactivate TULV both in a cell-free and cell-associated context and found that TULV was efficiently inactivated by all these methods similar to other enveloped RNA viruses. Finally, we successfully validated the complete inactivation using these inactivation methods using the highly pathogenic HCPS-causing New World Andes virus (ANDV) and the HFRS-causing Old World Hantaan virus (HTNV). These results provide valuable information about safe and effective inactivation methods of viral samples and about the environmental risk potential of hantaviruses.

Source: 

Link: https://journals.plos.org/plosntds/article?id=10.1371/journal.pntd.0013781

____

#Ebola #laboratory #preparedness at #frontline hospitals: can we or can’t we?

 

ABSTRACT

Frontline hospitals are required to care for patients with suspected viral hemorrhagic fever (VHF), yet guidance on laboratory preparedness remains fragmented and incomplete. We conducted a multidisciplinary risk assessment of our institutional capacity to perform routine diagnostic testing for VHF persons under investigation (PUI), focusing on the feasibility of using automated core laboratory instruments. Our assessment revealed substantial gaps between CDC guidance (which permits core lab testing) and the practical ability to implement it safely. Public health mandates for VHF preparedness have not been accompanied by granular guidance on biosafety, laboratory infrastructure, or regulatory clarity necessary for implementation. Community hospitals, which would benefit most from safely using their existing automated core laboratory instruments, lack the infrastructure, staffing expertise, and clear guidance to do so, while well-resourced tertiary centers are often best positioned to develop dedicated point-of-care testing (POCT)-based workflows. Federal and state authorities must provide explicit, validated examples of acceptable mitigation strategies for testing using core lab instrumentation and reconcile conflicting recommendations across guidance documents. Without such authoritative clarity, frontline hospitals cannot confidently meet their mandated VHF preparedness obligations.

Source: Journal of Clinical Microbiology, https://journals.asm.org/journal/jcm

Link: https://journals.asm.org/doi/10.1128/jcm.00903-26

____

Laboratory #Diagnosis of #Hendra and #Nipah: Two Emerging Zoonotic Diseases with One Health Significance

Abstract

Hendra virus (HeV) and Nipah virus (NiV) are two highly pathogenic RNA viruses with zoonotic potential, which can cause severe diseases with high mortality rates (50–100%) in humans and animals. Given this context, these viruses are classified as Biosafety Level 4 (BSL-4) pathogens, thus limiting research studies. Despite the high case fatalities, there are currently no human vaccines available for either virus, owing in part to the limitations in research and hesitancy in funding. In the absence of widespread vaccination, diagnostic tests are crucial for the rapid identification of cases and disease surveillance. This review synthesizes current knowledge on the epidemiology, transmission dynamics, and pathogenesis of NiV and HeV to contextualize a detailed assessment of the available diagnostic tools. We examined molecular and serological assays, including RT-PCR, ELISA, and LAMP, highlighting sample sources, detection windows, and performance. Diagnostic considerations across human and animal hosts are discussed, with emphasis on outbreak applicability and field-readiness, given the need for diagnostic assays that are suitable for use in low-income areas. Further development of diagnostic assays, including isothermal amplification tests and other next-generation approaches, is recommended to fill the gap in rapid, point-of-care diagnostics.

Source: Viruses, https://www.mdpi.com/1999-4915/17/7/1003

____

Modeling Effects of Routine #Screening for Accidental #Lab-Acquired #Infections on #Risk of Potential #Pandemic Pathogen #Escape from High-Biosafety Research Facilities

Abstract

Accidental lab–acquired infections (LAIs) risk releasing potential pandemic pathogens (PPPs) from BSL–3/4 facilities. We constructed a stochastic network infectious disease model to simulate how the probability of an outbreak of a pathogen resembling wild–type SARS–COV–2, following an initial LAI would be influenced by test–and–isolate interventions over a 100–day horizon. We varied test frequency (0–7 tests/week), peak sensitivity (50–100%), and isolation delay (0–3 days). For each of 192 parameter combinations, we conducted 1,000 simulations and used logistic regression to quantify how each parameter influenced the likelihood of an outbreak of 50 or more infections. Results indicated that even relatively infrequent routine testing significantly reduced the risk of outbreaks under diverse plausible scenarios, with greater reductions achieved at higher test frequencies. Once-weekly testing reduced outbreak risk by 52% under optimistic assumptions (80% sensitivity, 1–day delay) and by 29% under pessimistic assumptions (50% sensitivity, 2–day delay). Testing two and five times weekly yielded risk reductions of up to 62% and 71%, respectively, under optimistic assumptions, and 43% and 55%, respectively, under pessimistic assumptions. Logistic regression showed each additional weekly test decreased outbreak odds by 20%, each 10–point increase in test sensitivity reduced odds by 10%, and each additional isolation delay day increased odds by 15.5%. Interaction analyses revealed that longer isolation delays attenuated the protective effects of higher testing frequency and sensitivity. Routine lab worker screening with prompt isolation substantially mitigates PPP escape risks. High–frequency testing has the greatest impact, and policymakers should consider implementing regular screening protocols.

Source: MedRxIV, https://www.medrxiv.org/content/10.1101/2025.05.16.25327796v1

____