This installment of the Puscast reviews recent infectious disease literature from late August 2017, presenting findings on zoonotic disease origins, controversies in infection control, and vaccine efficacy. The host delivers a scathing critique of the Infectious Diseases Society of America (IDSA) for decades of silence against anti-vaccine movements. Key literature reviewed includes evidence for the European origin of the fatal white-nose fungus (P. destructans) affecting North American bats, confirmation of herd immunity via HPV vaccination programs, and data suggesting hospital contact isolation for common flora (MRSA/VRE) is ineffective when hand hygiene is excellent. The episode also highlights exotic zoonotic risks (anthrax from hippos, tularemia from dogs) and discusses the potential safety of using antibiotics instead of surgery for acute appendicitis.
Summary of the Infectious Disease Literature Review (Puscast)
0:32 Zoonotic Disease Origin: The bat-killing white-nose fungus (Pseudogymnoascus destructans) in the American Northeast appears to have originated in Europe (specimen found in France, 1918). European bats are immune, suggesting a necessary adaptation period for bat populations in the US.
1:51 Contact Isolation Inefficiency: Contact isolation is deemed ineffective and costly for controlling the spread of organisms that are part of the normal flora (MRSA, VRE), provided hand hygiene compliance is high. A Detroit study showed that discontinuing isolation for these pathogens resulted in no increase in hospital-acquired infections.
3:39 Failure of the IDSA (Opinion): The Infectious Diseases Society of America (IDSA) is explicitly labeled a "total embarrassment" for being "silent" for 20-30 years in the face of anti-vaccine movements, despite preventable deaths in Europe and the US.
5:16 Proof of Herd Immunity: Widespread HPV vaccination of females in Australia led to a marked decrease in the targeted HPV strains among males, serving as a clean demonstration that herd immunity is effective.
6:01 Bottled Water Risks: Bottled water is environmentally disastrous (takes 2,000x more energy than tap water) and is not inherently safe; an outbreak in Spain was traced to norovirus contamination from sewage in bottled artisian water.
7:32 Emerging Zoonoses: The Snowshoe Hare Virus (an Orthobunyavirus spread by mosquitoes) was identified as the cause of meningoencephalitis in a patient in Canada.
8:52 Rabies Transmission Negligence: Case reports from China detail fatal rabies transmission via organ transplants. The medical literature's tepid conclusion—that "more attention should be paid"—is rejected as inadequate for describing clear negligence.
10:03 Influenza Herd Immunity Complexity: A meta-analysis showed variable evidence for herd immunity resulting from mandated child influenza vaccination, illustrating the difficulty of studying highly transmissible viruses compared to HPV. (As far as I can tell, the data is inconclusive on population-wide flu benefits.)
11:33 Prior Vaccination Efficacy: A meta-analysis found no negative impact of prior season influenza vaccination on current season efficacy, counteracting previous studies (demonstrating "Newton's second law of the medical literature": for every study, there is an equal and opposite study).
13:24 Reduced Disease Severity: Vaccination against pertussis (whooping cough) provides significant benefits beyond prevention, including a 60% reduction in odds of severe disease and 30% reduction in post-tussive vomiting.
14:18 Splenectomy Vaccination Gaps: A study from Italy confirmed that proper vaccination coverage in splenectomized patients significantly reduces mortality, though compliance was low (only two-thirds received at least one vaccine).
15:34 Anthrax from Roadkill: An outbreak in Zambia occurred when villagers ate hippopotami that had died of anthrax, highlighting the high infection risk associated with consuming wild meat due to food insecurity.
17:27 Meningococcal Risk in MSM: Men who have sex with men (MSM) face an increased risk (Relative Risk 4.0; 10.1x if HIV positive) for meningococcal disease (Serogroup C). This low-incidence, high-risk group should receive the quadrivalent meningococcal vaccine.
19:00 CRE Infections in LTC: Carbapenem-Resistant Enterobacteriaceae (CRE) are causing severe soft tissue infections (16% mortality) in patients transferred from long-term care facilities, necessitating aggressive upfront surgical intervention.
20:10 Steroids for Outpatients: Use of steroids for acute lower respiratory tract infection (LRTIs) in outpatients (without COPD/asthma) provides no benefit in severity or duration. (From a rationalist standpoint, using immunosuppression for acute bacterial processes seems inherently risky.)
21:04 Mycoplasma Treatment Outcome: Treatment for Mycoplasma pneumoniae (Macrolides, Quinolones, or Tetracyclines) showed no difference in patient outcomes (length of stay, cost, mortality), suggesting the disease runs its course regardless of antibiotic choice or resistance.
24:37 PPI Risk Reaffirmed: Gastric acid suppression via Protein Pump Inhibitors (PPIs) increases the risk for C. difficile, general gastroenteritis, and Norovirus, underscoring the vital role of stomach acid as an infection barrier.
26:11 Antibiotics for Appendicitis: A long-term follow-up study supports the safety and efficacy of treating acute appendicitis with antibiotics alone in adults, with a manageable 15% relapse rate. This supports the theory that many cases are caused by bacterial invasion (Fusobacterium necrophorum) rather than mechanical blockage.
27:09 New Hypervirulent Superbug: China reported a new Klebsiella strain that is simultaneously hypervirulent, multi-drug resistant (carbapenemase producer), and highly transmissible.
27:58 Malaria and Evolution: A new genetic mutation (nitric oxide synthetase 2 gene promoter) was identified as an evolutionary defense against acute malaria, further demonstrating malaria's profound historical impact on the human genome.