Episode #82 of the Infectious Disease Puscast features Dr. Daniel Griffin and Dr. Sara Dong reviewing recent infectious disease literature. Key discussions include new modeling data predicting nearly a million averted congenital rubella syndrome cases by 2055 through universal vaccine introduction, and findings on rare, clinically insignificant HIV superinfection in HIV-positive kidney transplant recipients. The hosts also highlight a broader definition of healthcare-associated RSV, revealing higher incidence than previously recognized. In the bacterial section, they cover fatal tularemia in beluga whales and a significant study showing persistent and spreading macrolide resistance in Streptococcus pneumoniae following azithromycin mass drug administration in Malawi. They discuss successful implementation of antibiotic de-escalation protocols for febrile neutropenia and optimizing cefazolin dosing for CNS infections. Fungal topics include a high prevalence of Histoplasma antigenuria in advanced HIV patients in Côte d'Ivoire and the efficacy of interferon-gamma therapy for refractory disseminated coccidioidomycosis, alongside practical guidance for dimorphic fungal diagnostics. Parasitic discussions feature a fatal case of primary amebic meningoencephalitis linked to nasal irrigation with RV water and new evidence for plausible local transmission of fishborne trematodiases in the U.S. Finally, a pilot study on the efficacy of coughing into a shirt for respiratory pathogen containment and a novel approach to malaria control using bed nets that "disinfect" mosquitoes by targeting parasites are presented.
Exploring Recent Advances in Infectious Diseases: From Global Health to Clinical Practice
0:00 Introduction and Show Overview: Hosts Dr. Daniel Griffin and Dr. Sara Dong provide an overview of the infectious disease literature reviewed in this episode.
2:19 Global Rubella Elimination Efforts: A modeling study projects that universal rubella-containing vaccine (RCV) introduction in 19 countries could avert nearly 1 million cases of congenital rubella syndrome (CRS) between 2025 and 2055, prompting a WHO recommendation for universal RCV in these regions.
4:15 HIV Superinfection in Transplant: Research on kidney transplant recipients with HIV who received HIV-positive organs (HIV D+/R+) found that HIV superinfection is rare and does not lead to significant clinical issues, supporting the safety of such transplants.
6:01 Under-recognized RSV Transmission: A study using an expanded definition for healthcare-associated respiratory syncytial virus (RSV) identified a significantly higher incidence (10.6% vs. 4.6% by traditional definition), underscoring the need for improved infection control in healthcare settings.
8:54 Tularemia in Wildlife: Fatal cases of tularemia, caused by Francisella tularensis subspecies holarctica, were reported in stranded beluga whales in Cook Inlet, Alaska, with transmission likely occurring through contaminated brackish water.
12:28 Azithromycin Resistance Concerns: A follow-up study 3.5 years after mass drug administration (MDA) of azithromycin in Malawi revealed persistent and widespread macrolide resistance in Streptococcus pneumoniae, affecting even children born after the trial, raising public health concerns about antimicrobial resistance.
19:25 Optimizing Antibiotic Use: The implementation of a structured antibiotic de-escalation protocol in hematology patients with febrile neutropenia significantly reduced inappropriate antibiotic use (from 45.5-66.7% to a median of 23.35%) without compromising patient safety.
22:04 Cefazolin for CNS Infections: New research suggests cefazolin is a viable treatment option for methicillin-susceptible Staphylococcus aureus (MSSA) central nervous system (CNS) infections, with optimal dosing strategies (e.g., continuous infusion) and consideration of albumin levels being important for efficacy.
24:58 Histoplasmosis in Advanced HIV: A study in Côte d'Ivoire found a high prevalence (24%) of Histoplasma antigenuria in patients with advanced HIV, comparable to tuberculosis prevalence, indicating histoplasmosis is a significant and potentially preventable cause of death in this vulnerable population.
26:47 Interferon-γ for Coccidioidomycosis: Adjunctive interferon-gamma (IFN-γ) therapy demonstrated overall favorable responses in patients with refractory disseminated coccidioidomycosis, particularly in those without specific inborn errors of immunity like STAT1 gain-of-function mutations.
29:56 Dimorphic Fungal Diagnostics Guidance: New practical guidance provides a centralized, algorithm-based resource for clinical microbiology laboratories and clinicians on antibody and antigen detection methods for diagnosing dimorphic fungal infections.
32:35 Nasal Irrigation and PAM Risk: A fatal case of primary amebic meningoencephalitis (PAM) in Texas was linked to nasal irrigation using inadequately disinfected recreational vehicle (RV) water, highlighting the critical importance of using distilled, sterile, or boiled water for nasal irrigation.
34:45 Emerging Fishborne Trematodiases: Evidence suggests the plausible local transmission of fishborne trematodiases in the U.S. due to the introduction of an intermediate host snail and the common practice of eating raw, unfrozen game fish.
40:43 Effective Cough Etiquette: A pilot study found that coughing into a shirt significantly reduces the maximal respiratory plume area (95.4% reduction) compared to unobstructed coughing, performing better than coughing into the elbow and comparably to a mask, suggesting a highly effective respiratory etiquette maneuver.
46:50 Novel Malaria Control: Researchers developed a new method for malaria control using insecticide-treated bed nets coated with compounds that "disinfect" mosquitoes by killing malaria parasites, preventing transmission without contributing to insecticide resistance.
49:00 Concluding Remarks: The hosts conclude the podcast by encouraging listeners to access show notes, subscribe, engage with the content, and support MicrobeTV's science shows.