This episode of the Infectious Disease Puscast features Drs. Daniel Griffin and Sara Dong reviewing significant literature from early August 2025. The discussion covers a range of topics in viral, bacterial, and parasitic diseases, as well as vaccine effectiveness.
Key findings include a study demonstrating that the recombinant zoster (shingles) vaccine is associated with a significantly lower risk of heart attack and stroke in older adults. In bacteriology, Dalbavancin was found to be non-inferior, though not superior, to standard care for complicated Staphylococcus aureus bacteremia, suggesting its utility in simplifying treatment. Other studies highlighted the critical importance of timely antibiotic administration for Stenotrophomonas maltophilia pneumonia, the utility of PCR in detecting seronegative primary syphilis, and the potential of oral cefixime as an alternative for early syphilis treatment. Parasitology discussions revealed the expanding season for Babesia in New England due to climate change and a trial showing ivermectin can reduce malaria incidence, possibly through a dual mechanism of killing both the mosquito vector and the parasite. Finally, the podcast reviews evidence supporting the use of high-dose or adjuvanted influenza vaccines for adults over 65, which significantly reduces hospitalizations and mortality compared to standard-dose vaccines.
A Review of Recent Infectious Disease Literature
1:45 Shingles Vaccine's Link to Cardiovascular Health: A study in Clinical Infectious Diseases on adults over 50 found that the recombinant zoster (shingles) vaccine was associated not only with a 73% reduction in shingles of the eye but also with a 28% lower risk of hospitalized heart attack (MI) and a 42% lower risk of hospitalized stroke. This suggests significant cardiovascular benefits beyond preventing the rash.
5:39 Dalbavancin for Complicated Staph Bacteremia: A randomized trial in JAMA compared a two-dose course of Dalbavancin to 4-8 weeks of standard IV therapy for complicated S. aureus bacteremia. While Dalbavancin was not found to be superior based on a composite outcome score, it was non-inferior in terms of clinical efficacy. This supports its use as a simpler, effective option for completing therapy after initial blood culture clearance.
13:40 Importance of Timely Antibiotics for Stenotrophomonas Pneumonia: A study in Open Forum Infectious Diseases demonstrated that initiating effective antibiotic therapy within 48 hours for Stenotrophomonas maltophilia pneumonia significantly improves outcomes. Timely treatment resulted in a 22.8% absolute reduction in 30-day mortality compared to delayed therapy.
17:09 Detecting Primary Syphilis with PCR: A systematic review and meta-analysis found that approximately 10% of primary syphilis infections that are positive by PCR on a lesion swab are negative on all serological tests at the initial visit. This highlights that relying on serology alone can miss one in ten cases of early, infectious syphilis.
19:14 Oral Cefixime as an Alternative for Early Syphilis: A small randomized trial compared a 14-day oral course of cefixime to a standard injection of benzathine penicillin G for early syphilis. While penicillin showed a faster serological response at 3 months, both treatments achieved similar high success rates (over 93%) by 12 months, positioning cefixime as a potential alternative during penicillin shortages.
23:55 The Expanding Babesia Season: A 30-year retrospective cohort study from New England shows that due to climate change, the season for symptomatic babesiosis has expanded dramatically. The average number of months with cases rose from 2.2 before the year 2000 to 9.2 after 2015, meaning clinicians should consider the diagnosis nearly year-round.
26:27 Ivermectin for Malaria Control: A cluster-randomized trial in Kenya, published in the NEJM, found that mass administration of ivermectin once a month for three months resulted in a 26% lower incidence of malaria infection in children compared to a control group. The benefit may be twofold: killing mosquitoes that feed on treated individuals (vector control) and a direct anti-parasitic effect.
29:41 High-Dose Flu Vaccine Effectiveness in Older Adults: A post-hoc analysis of a randomized trial confirmed the benefit of high-dose influenza vaccines for adults aged 65-79. Compared to the standard-dose vaccine, the high-dose version was associated with a significantly lower risk of hospitalization for pneumonia/influenza and a roughly 74% reduction in all-cause mortality, regardless of the patient's frailty.