Hello Health Rounds readers! As wildfires rage across Los Angeles, we feature a study that found health risks to those who return to homes left standing. We also report on a promising experimental drug to relieve flu symptoms, and an alarming forecast for rising US dementia rates.

In breaking news, see these stories from our Reuters journalists: Some LGBTQ people race to claim rights, fearing rollbacks under Trump; drugmakers rush to sign deals on first day of industry conference; FDA proposes nutrition labels on front of packaged foods, and US judge blocks FDA graphic warning label requirement for cigarettes.

Also: Lawsuits target fluoride in kids' toothpastes; US warns of health risks from sewage use for fertilizer; UK bans imports of German hams after foot-and-mouth case; EU finds China is limiting access to medical device market; and why autism rates are rising.

Residents who returned to unburned homes after a 2021 wildfire near Boulder, Colorado often reported health issues months later, a study has found.

The most common symptoms reported by survey participants six months after the Marshall Fire were itchy or watery eyes (33%), headache (30%), dry cough (27%), sneezing (26%), and sore throat (23%).

These remained the most reported symptoms a year after the fire, but at lower rates, researchers reported in ACS ES&T Air.

Wildfires that rage in cities, like the Marshall Fire and the ones spreading now across Los Angeles, burn not just natural vegetation but also high amounts of human-made materials, which emit high levels of polycyclic aromatic hydrocarbons and volatile organic compounds that are linked to negative health outcomes.

Smoke exposure symptoms were most often reported by residents whose homes were within 250 meters (820 feet) of burned structures. Dry coughs, itchy/watery eyes and sneezing were also associated with a change in the home’s smell post-fire and with findings of smoke damage or ash inside.

Many participants said cleaning their homes, using HVAC systems, hiring cleaning companies, or replacing affected furniture or carpets helped reduce the smell over time.

The researchers did not sample ash or indoor air quality in the homes, and they did not have information on how much time residents spent in their homes or how they cleaned them after the fire, which could impact their exposure to chemicals.

Still, they say, because the reported health symptoms are likely due to inhalation of gaseous pollutants or re-suspended dust, personal protective equipment such as masks, preferably N95 or KN95 masks, gloves, and gowns should be provided for residents who are cleaning smoke-damaged homes after wildfires.

An experimental pill speeds recovery from influenza without inducing the dangerous mutations in the flu virus that have resulted from similar drugs, according to results from a Chinese study.

In a trial involving 527 otherwise healthy children and adults with non-severe cases of the flu – predominantly due to influenza A - a single oral dose of suraxavir marboxil shortened the median time to alleviation of symptoms to 42 hours, from 63 hours with a placebo.

Resolution of fever, cough, sore throat, headache, nasal congestion, muscle or joint pain, and fatigue was 21 hours faster with suraxavir, which is under development by China's Jiangxi Qingfeng Pharmaceutical Co.

Patients who received suraxavir also had more rapid decreases in viral load, according to a report in Nature Medicine.

The drug acts by inhibiting the polymerase acidic (PA) protein that helps the influenza virus replicate.

Roche's PA inhibitor, baloxavir marboxil, sold under the brand name Xofluza, has shown similar benefits, but viral mutations that confer resistance to its effects develop quickly, particularly in children.

Suraxavir, however, “had a remarkably low incidence of drug resistance,” at less than 1%, the researchers reported.

Everyone in the trial was treated within two days of symptom onset. The researchers next hope to study the effect of later administration, and the drug’s efficacy and safety in high-risk patients.