Top 5 Infectious Disease News Stories Week of January 4-10

Entering Peak Norovirus Season as Cases Rise Across the US

Norovirus cases have risen sharply across the US, with more than 22% of tests returning positive as of late December 2024, a significant increase from the previous year. The CDC reported 495 outbreaks during the 2024–2025 season, up from 363 in the same period in 2023. In response to a norovirus outbreak linked to contaminated oysters, the FDA issued a safety alert on January 2, 2025, advising consumers and businesses in Washington and Oregon to avoid oysters harvested from Hammersley Inlet between December 2nd through the 17th in 2024. These oysters may carry norovirus, which causes gastrointestinal illness and can lead to dehydration, especially in vulnerable populations. Health officials are urging increased vigilance as norovirus activity typically peaks in late fall and winter.

The First Patient in US With Severe Case of Avian Influenza Dies

The Louisiana Department of Health confirmed the first US death linked to the H5N1 avian influenza virus on January 7, 2025. The patient, who was older and had underlying health conditions, contracted the virus after exposure to a combination of backyard poultry and wild birds. No further cases or person-to-person transmission have been detected. This case involved the D11 genotype of the H5N1 virus, which has been linked to more severe illness compared to the B313 genotype seen in previous outbreaks. The D11 genotype had also caused a severe case in a young girl in Canada, who required ECMO but eventually recovered.

Bacteria Use Natural Products to Expose Competitors to Viruses, Opening New Pathways for Antimicrobial Strategies

A recent study published in Nature reveals how bacteria use natural products to increase their competitors' vulnerability to viral infections. Researchers, led by Joseph Gerdt, an assistant professor of chemistry at Indiana University, discovered that Streptomyces bacteria secrete coelichelin, a secondary metabolite that binds iron and disrupts key regulatory processes in Bacillus subtilis, making it more susceptible to infection by bacteriophages. This finding adds a new layer to our understanding of microbial competition and suggests potential applications in phage therapy, particularly for antibiotic-resistant infections. While the study focused on non-human microbes, the implications for shaping microbial communities and developing therapeutic strategies are significant. Gerdt and his team are now exploring the broader impact of these interactions, particularly in human microbiomes, and how natural products might enhance phage therapy.

FDA Requires Guillain-Barré Syndrome Warning on 2 RSV Vaccines

The FDA has mandated safety labeling changes for the RSV vaccines Abrysvo (Pfizer) and Arexvy (GSK) after clinical trial data, reports from the Vaccine Adverse Event Reporting System (VAERS), and a postmarketing study revealed an increased risk of Guillain-Barré Syndrome (GBS) in seniors. The study, which assessed the risk in individuals aged 65 and older, found an estimated 9 excess cases of GBS per million doses of Abrysvo and 7 excess cases per million doses of Arexvy. Although the data suggests a higher risk of GBS following vaccination, the evidence is insufficient to establish a causal link. GBS is a rare neurological disorder where the immune system attacks the peripheral nervous system, potentially leading to life-threatening paralysis.

Long COVID Subsides in a Majority of Healthcare Workers

A study of healthcare workers (HCWs) in Switzerland found that while the burden of post-acute sequelae of SARS-CoV-2 infection (PASC) decreased over a 2.5-year period, 1% of respondents still reported significant restrictions in their daily lives. The study followed 1,704 HCWs from March 2021 to October 2023, and revealed that 30.7% experienced at least one PASC symptom by October 2023, with those infected with the original wild-type SARS-CoV-2 strain more likely to report symptoms. Despite the overall reduction in long COVID symptoms, some HCWs still faced challenges, with 15% of those affected indicating severe restrictions in their daily activities.