New study shows that close surgical margins of tumors do not increase risk of local cancer recurrence in children treated for non-rhabdomyosarcoma soft tissue sarcomas.

During the devastating 2025 Los Angeles Eaton firestorm’s peak, airborne lead concentrations exceeded 80 times the normal background levels, new research finds. The work establishes that this urban smoke plume – which also included heightened levels of arsenic, halogens, and heavy metals – was far more hazardous than a wildland plume the year prior. “Millions of residents faced an acute toxic metal burden with unknown health consequences,” Haroula Baliaka and colleagues write. “Understanding and ultimately mitigating these health risks must become a priority as such [urban] events grow more frequent and severe.” As humans expand into traditional wildlands, urban wildfires are becoming increasingly common. These fires produce smoke that contains far more chemical pollutants than forest and grassland fires. The 2025 Los Angeles firestorm, originating in Eaton Canyon, obliterated more than 9,000 structures. It coated the Los Angeles basin with a plume of chemicals from burning electronics, building materials, and vehicles. Now, Baliaka et al. have characterized the plume’s changing composition during the fire. They analyzed its composition of airborne trace elements, tracking hourly potassium-lead ratios. Compared with the content of a nearby 2024 wildland-exclusive fire plume, the Los Angeles Eaton plume had a more than 50-fold higher concentration for lead, 7-fold higher for halogens (chlorine and bromine), 4-fold for zinc, and 3-fold for copper and arsenic. Baliaka et al.’s analyses suggest that, at peak burn, lead concentrations exceeded 80 times the typical background level for around 7 million residents over 24 hours.

Dengue virus is especially pernicious compared with many other viruses, as secondary infections can actually be worse than the first one. Now, a new phase 1 trial involving controlled infections in volunteers provides a treasure trove of details about how preexisting immunity and anti-dengue antibodies affect the nature of secondary infections with dengue. The findings are among the first to glean insights using a large controlled human challenge, and could inform future therapeutics and the design of more broadly protective vaccines. Secondary infections with dengue are often the most severe ones, as preexisting antibodies can boost viral counts and raise the risk of severe symptoms. This has frustrated the development of badly needed vaccines for dengue. Furthermore, it’s been challenging to understand how pre-infection affects dengue outcomes, as animal models have many limitations and patients usually don’t present until after viral counts have peaked. In this study, Camila Odio and colleagues recruited 45 healthy adults who had either zero, one, or more than one prior infection with any of the four strains of dengue virus (DENV1-DENV4). The volunteers received injections of a live, weakened strain of DENV3 in a challenge study, allowing the researchers to fully interrogate dengue immunity dynamics in humans in a safe and controlled setting. The team made various discoveries: for example, they found that people whose antibodies boosted the replication of the virus had the highest viral counts and waning of CD8-bearing T cells and antibodies. Meanwhile, people who had higher amounts of antibodies against the viral nonstructural protein 1 displayed more balanced immune responses and lower viral counts. “Collectively, this work confirms multiple hypotheses generated by natural history studies and reveals the optimal conditions for inducing potent and persistent immunity against DENV1 to DENV4,” Odio et al. conclude. For reporters interested in trends, a July 2025 study in Science Translational Medicine involving some of the same authors identified a class of anti-dengue antibodies that correlated with broad protection and lower disease risk in a cohort of children: https://www.science.org/doi/10.1126/scitranslmed.adq0571

Higher levels of human development are associated with better universal health coverage worldwide, and disparities in coverage between income groups are generally larger than disparities between world regions. Those are two of the conclusions of a new study published this week in the open-access journal PLOS Global Public Health by Akira Hayasaka of Yokohama City University, Japan, Yasuhiro Nakanishi of the National Institute of Public Health, Japan, and colleagues.

An analysis of 14.4 billion medical insurance claims has uncovered limitations in earlier studies, offering a more reliable way to measure the long-term health effects of COVID-19.