Target Review Group: Clinical Infectious Disease Specialists and Hospital Epidemiologists
Abstract
This clinical digest, presented as a "Puscast," synthesizes a broad range of infectious disease literature from early April 2011. The report evaluates clinical trials and case reports spanning infection control protocols, viral shedding dynamics, and diagnostic yields for bone infections. Key findings include the limitations of fever as a marker for influenza infectivity in healthcare workers and the superior diagnostic yield of open biopsies over CT-guided needles in vertebral osteomyelitis.
Infection prevention is a recurring theme, with a critical assessment of "It’s Okay to Ask" hand hygiene campaigns and a review of the Veterans Affairs (VA) successful MRSA bundle. The summary also covers vaccination updates regarding Zoster, Hepatitis B, and Yellow Fever, while providing epidemiological insights into emerging threats like the NDM-1 carbapenemase in environmental water supplies and human-to-primate viral transmission.
Clinical Summary and Key Takeaways
1:36 Hand Hygiene & Patient Advocacy: Analysis of the "It’s Okay to Ask" program indicates low efficacy; 57% of the public are unlikely to question physicians, and 43% assume competence. The program is characterized as a failure of institutional responsibility for basic standards of care.
3:18 Influenza Shedding in Healthcare Workers: A Seattle-based study found that 75% of healthcare personnel shed influenza (detected by PCR) while afebrile. Fever is concluded to be an unreliable criterion for determining when staff can safely return to work without risking patient transmission.
5:43 Cochrane Review Critique (Zoster/PHN): The podcast highlights a perceived lack of utility in specific meta-analyses, noting that preventing Herpes Zoster via vaccination inherently prevents post-herpetic neuralgia, rendering some evidentiary "uncertainties" in literature pedantic.
6:41 Varicella Reinfection Risk: A case report documents an immunocompetent, seropositive physician contracting varicella after exposure to a patient with localized zoster. This underscores that prior infection or positive titers do not guarantee absolute immunity.
7:35 CMV and Guillain-Barré Syndrome (GBS): Research indicates the risk of GBS following primary Cytomegalovirus (CMV) infection is 0.6 to 2.2 per 1,000 cases, comparable to Campylobacter jejuni.
8:53 Smallpox/Vaccinia Transmission: A cluster of vaccinia infections in a Maryland martial arts gym suggests secondary transmission from a vaccinated individual (likely military) via fomites or physical contact.
10:51 VA MRSA Bundle Success: Implementation of a multi-faceted bundle (universal screening, contact precautions, and culture change) resulted in a 62% reduction in MRSA infections in ICUs and a 45% reduction in non-ICU settings.
13:45 Vertebral Osteomyelitis Diagnostics: Diagnostic yield for hematogenous vertebral osteomyelitis is significantly higher in open biopsies (91%) compared to CT-guided needle biopsies (53%). Crucially, pre-biopsy antibiotic exposure did not significantly reduce pathogen recovery.
15:18 Community-Acquired Pneumonia (CAP) Duration: For severe but uncomplicated CAP, a 7-day antibiotic course demonstrated non-inferiority to longer durations regarding 30-day mortality and secondary complications.
17:08 Eosinophilia as a Diagnostic Marker: In asymptomatic short-term travelers, blood eosinophilia has a poor positive predictive value (15% for old infections, 0% for recent) for helminthic infections like Schistosomiasis or Strongyloidiasis.
18:39 Zoonotic & Viral Transmission: Evidence of human-to-gorilla transmission of Metapneumovirus was reported in Rwanda. Additionally, attitudes toward H1N1 vaccination were found to be highly volatile, with a narrow one-week "window of opportunity" for vaccination before anti-vaccine sentiment influenced patients.
20:35 Fungal and Viral Epidemiology:Penicillium marneffei (Talaromycosis) shows strong seasonality linked to the rainy season and rodent vectors. Accelerated Hepatitis B vaccination (0, 1, and 3 weeks) is effective for HIV-positive patients with CD4 counts >500.
22:39 Rabies & Yellow Fever: A Michigan death highlights the necessity of post-exposure prophylaxis following bat contact, even without visible bites. A new inactivated Yellow Fever vaccine shows efficacy comparable to the live attenuated version without the risk of viscerotropic disease.
24:32 Catheter Tip Culturing: Routine culturing of intravenous catheter tips is deemed unnecessary unless the patient is bacteremic or fungemic.
25:58 Global Health & Resistance: Typing of Vibrio cholerae in Haiti confirms a single point-source origin. In environmental news, NDM-1-producing organisms have been identified in the public water supply of New Delhi.
27:58 Wound Botulism & Sepsis: Recurrent wound botulism is documented among injection drug users in California. Regarding sepsis management, a meta-analysis suggests initiating corticosteroids only in patients requiring ≥0.5 μg/kg/min of norepinephrine.
31:20 Cefazolin Breakpoints: Updated CLSI breakpoints for Enterobacteriaceae require a 2g every 8 hours dosing regimen for cefazolin to maintain "susceptible" status.