The highly contagious SARS-CoV-2 virus is primarily transmitted through respiratory droplets, aerosols, and contaminated surfaces. In addition to antiviral drugs, the decontamination of surfaces and personal protective equipment (PPE) is crucial to mitigate the spread of infection. Conventional approaches, including ultraviolet radiation, vaporized hydrogen peroxide, heat and liquid chemicals, can damage materials or lack comprehensive, effective disinfection. Consequently, alternative material-compatible and sustainable methods, such as nanomaterial coatings, are needed. Therefore, the antiviral activity of two novel zinc-oxide nanoparticles (ZnO-NP) against SARS-CoV-2 was investigated in vitro. Each nanoparticle was produced by applying highly efficient “green” synthesis techniques, which are free of fossil derivatives and use nitrate, chlorate and sulfonate salts as starting materials and whey as chelating agents. The two “green” nanomaterials differ in size distribution, with ZnO-NP-45 consisting of particles ranging from 30 nm to 60 nm and ZnO-NP-76 from 60 nm to 92 nm. Human lung epithelial cells (Calu-3) were infected with SARS-CoV-2, pre-treated in suspensions with increasing ZnO-NP concentrations up to 20 mg/mL. Both “green” materials were compared to commercially available ZnO-NP as a reference. While all three materials were active against both virus variants at concentrations of 10–20 mg/mL, ZnO-NP-45 was found to be more active than ZnO-NP-76 and the reference material, resulting in the inactivation of the Delta and Omicron SARS-CoV-2 variants by a factor of more than 10⁶. This effect could be due to its greater total reactive surface, as evidenced by transmission electron microscopy and dynamic light scattering. Higher variations in virus inactivation were found for the latter two nanomaterials, ZnO-NP-76 and ZnO-NP-ref, which putatively may be due to secondary infections upon incomplete inactivation inside infected cells caused by insufficient NP loading of the virions. Taken together, inactivation with 20 mg/mL ZnO-NP-45 seems to have the greatest effect on both SARS-CoV-2 variants tested. Prospective ZnO-NP applications include an antiviral coating of filters or PPE to enhance user protection.

Fungal infections are becoming an escalating public health challenge, particularly among immunocompromised individuals. The partially limited efficacy of current antifungal treatments, their potential adverse effects, and the increasing problem of resistance emphasize the need for new treatment options. Existing antifungal classes-allylamines, azoles, echinocandins, polyenes, and pyrimidine analogs-face challenges due to their similarity with human cells and rising resistance. New antifungal agents, such as ibrexafungerp, rezafungin, oteseconazole, and miltefosine, offer novel mechanisms of action along with reduced toxicity. While antifungal resistance is a growing global concern, fungal infections in low- and middle-income countries (LMICs) present specific challenges with high rates of opportunistic infections like cryptococcosis and endemic mycoses such as histoplasmosis. The World Health Organization's fungal priority pathogens list highlights the prevalence of these infections in LMICs, where limited access to antifungal drugs and misuse are common. This review provides a comprehensive overview of these new agents and their mechanisms, and explores the challenges and roles of antifungal drugs in LMICs, where the burden of fungal infections is high. Continued research and development are essential to address the rising incidence and resistance of fungal infections globally.