Dr Fabrício Campos

#H5N1 #Influenza #OneHealth #Spillover #GenomicSurveillance #Reassortment #EmergingViruses

Butt et al., 2026. doi.org/10.64898/202...
Cha et al., 2026. pmc.ncbi.nlm.nih.gov/articles/PMC...
Son et al., 2026. pmc.ncbi.nlm.nih.gov/articles/PMC...
10/10

The threshold for sustained human-to-human transmission has not been crossed. Yet H5N1 is not static. It is evolving rapidly as new hosts enter the adaptive landscape of viral selection. 9/10

Cats function as biological sentinels of intermediate adaptation: no evidence yet of human-type receptor affinity, but clear signals of viral plasticity in mammals with close human contact. 8/10

These studies show that the virus maintains avian receptor specificity, yet genotypic diversity modulates transmission and neuropathogenicity. The avian reservoir continues producing new variants through reassortment. 7/10

Meanwhile, Cha et al. show that clade 2.3.4.4b continues generating new genotypes (23G0–G2; 24G0–G4) in South Korea, including a novel H5N3 from reassortment. H5N1, H5N6 and H5N3 co-circulate across East Asia. 6/10

Genotype B3.13 showed higher viral shedding and efficient cat-to-cat transmission. D1.1 caused more prolonged disease but without detectable transmissibility. Small genotypic differences profoundly alter the epidemiological phenotype. 5/10

In the preprint by Butt et al., two genotypes (B3.13 and D1.1) behave very differently in cats. The virus replicates in the upper respiratory tract, spreads via viremia, and invades the CNS by crossing the blood–brain barrier through endothelial infection. 4/10

In practical terms, severe infection in cats did not indicate adaptation for efficient human-to-human transmission. However, the scenario becomes more complex, as shown in the next study. 3/10

In South Korea, Son et al. analyzed two fatal feline outbreaks in 2023. Despite high pathogenicity and mammalian contact transmission, isolates retained strong affinity for α2,3 (avian-type) receptors and showed no detectable binding to α2,6 (human-type). 2/10

Post 85 — H5N1: when cats reveal the limits (and risks) of viral adaptation

H5N1 continues to expand its ecological space, but the feline interface helps distinguish two distinct levels of risk: host adaptation and transmission capacity. 1/10

#Microbiome #SoilMicrobiology #Rhizosphere #Eucalyptus #FunctionalRedundancy #Ecology #Bioinformatics #ForestSystems #EnvironmentalFiltering.

www.preprints.org/manuscript/2...

8/8

Even as an exploratory comparative study, these findings help explain how commercial forest systems may maintain nutrient cycling stability despite strong ecological contrasts. Ecology shapes structure.
Function persists. 7/8

We integrated: i) soil physicochemical characterization; ii) high-resolution ASV inference; iii) phylogenetic reconstruction; and PICRUSt2-based functional prediction. A deep ecological-bioinformatic exploration of plantation rhizospheres. 6/8

We also detected regional specialization: (1) Eldorado do Sul: higher predicted potential for chitin degradation, purine turnover, and nitrifier-denitrification. (2) Três Lagoas: enrichment in alternative TCA variants, glyoxylate pathways, and aromatic compound degradation. 5/8

This suggests that rhizosphere microbiomes can undergo strong compositional divergence while maintaining a resilient predicted functional framework. Environmental filtering shapes who is there, but dominant lineages preserve what gets done. 4/8

Only 8.1% of ASVs were shared between sites. Yet central carbon metabolism, amino acid biosynthesis, and energy production pathways were highly similar. High taxonomic turnover. Functional backbone stability. 3/8

Although bacterial communities were profoundly different in composition (Jaccard = 0.915; Bray–Curtis = 0.843), dominant metabolic functions remained largely conserved. Species changed. Core metabolic architecture persisted. 2/8

New Preprint: Taxonomic divergence and functional stability in eucalyptus rhizosphere microbiomes across contrasting Brazilian regions. What we found was unexpected and ecologically meaningful.
www.preprints.org/manuscript/2...
1/8

Li et al., 2026. doi.org/10.46234/ccd...
Melo et al., 2026. doi.org/10.3390/v180...
Thompson et al., 2026. doi.org/10.1177/1040...
Wille et al., 2026. doi.org/10.64898/202...
13/13

H5N1 does not recognize geographic or ecological boundaries; it is a planetary virus awaiting surveillance at its scale.

#H5N1 #InfluenzaA #OneHealth #PandemicPreparedness

Granstad et al., 2026. doi.org/10.64898/202...
12/13

From the poles to raw milk, the pattern is consistent: multiple introductions, reassortment, progressive adaptation, and fragmented surveillance. 11/13

Since 2021, this clade has been associated with 82 human cases, reinforcing a scenario of progressive adaptation and expanded zoonotic risk. 10/13

Li et al. demonstrate that clade 2.3.4.4b sustains transmission in mammals, accumulating adaptive mutations such as PB2-E627K and D701N. 9/13

Notably, viral RNA was not consistently detected in blood or feces, suggesting localized replication in the mammary gland and silent circulation within the production system. 8/13

Meanwhile, Thompson et al. show that in the U.S. dairy outbreak, H5N1 exhibited functional mammary tropism. Milk from affected cows was 6× more likely to test positive than controls. 7/13

By 2025, viruses isolated from Arctic foxes already carried PB2-E627K and PB1-H115Q; classical markers of mammalian adaptation. 6/13

In the Arctic, Granstad et al. document multiple independent H5N1 introductions (2022–2025) into Svalbard and Jan Mayen. 5/13

Melo et al. describe a complementary scenario: no active infection in seabirds on King George Island, yet 11.3% had antibodies against influenza A. H5 subtypes were detected serologically in skuas. 4/13

All genomes belonged to a single lineage distinct from that detected the previous summer, a signal of new introduction and viral replacement on the Antarctic Peninsula. 3/13

In Antarctica, Wille et al. confirm that the virus is established on the continent. Although >500 environmental samples from penguins and marine mammals were negative, almost all dead skuas were positive. 2/13