tetano
Editor, Senior Moderator
Sci Rep
. 2026 Mar 9.
doi: 10.1038/s41598-026-41122-0. Online ahead of print.
Emergence of a novel reassorted high pathogenicity avian influenza A(H5N2) virus associated with severe pneumonia in a young adult
Joel Armando Vázquez-Pérez[SUP] 1 [/SUP], Eduardo Becerril-Vargas[SUP] 1 [/SUP], José Ernesto Ramírez-González[SUP] 2 [/SUP], Mario Solís-Hernández[SUP] 3 [/SUP], Charles Todd Davis[SUP] 4 [/SUP], Pamela Garciadiego-Fossas[SUP] 1 [/SUP], Marco Villanueva-Reza[SUP] 1 [/SUP], Hansel Hugo Chávez-Morales[SUP] 1 [/SUP], Enrique Mendoza-Ramírez[SUP] 1 [/SUP], Christian Diego Olivares-Flores[SUP] 1 [/SUP], América Citlali Vera-Jiménez[SUP] 1 [/SUP], Uriel Rumbo-Nava[SUP] 1 [/SUP], Cristóbal Guadarrama-Pérez[SUP] 1 [/SUP], Elio Germán Recinos-Carrera[SUP] 1 [/SUP], Joaquín Zúñiga[SUP] 1 [/SUP], Irma López-Martínez[SUP] 2 [/SUP], Lucía Hernández-Rivas[SUP] 2 [/SUP], Gisela Barrera-Badillo[SUP] 2 [/SUP], Nohemí Colin-Soto[SUP] 5 [/SUP], Laura Flores-Cisneros[SUP] 5 [/SUP], Guillermo Carbajal-Sandoval[SUP] 5 [/SUP], Diana Vidal-Aguirre[SUP] 5 [/SUP], Dayanira Sarith Arellano-Suarez[SUP] 2 [/SUP], Rodrigo Aparicio-Antonio[SUP] 2 [/SUP], Ramiro López-Elizalde[SUP] 6 [/SUP], Carlos Javier Alcazar-Ramiro[SUP] 3 [/SUP], Armando García-López[SUP] 3 [/SUP], Han Di[SUP] 4 [/SUP], Marie Kirby[SUP] 4 [/SUP], Yunho Jang[SUP] 4 [/SUP], Miguel Angel Lezana-Fernández[SUP] 5 [/SUP], Carmen Margarita Hernández-Cárdenas[SUP] 7 8 [/SUP]
Affiliations
Infection of backyard and poultry with low pathogenicity avian influenza LPAI A(H5N2) viruses has occurred in Mexico since 1994, and the first human infection caused by this influenza virus was detected in 2024. Since its emergence in the Americas, frequent reassortments between high pathogenicity avian influenza HPAI A(H5N1) and LPAI viruses has occurred. In September 2025, the Instituto Nacional de Enfermedades Respiratorias of Mexico City identified an unsubtypeable influenza A virus infection in a young adult patient later determined to be a reassortant HPAI (H5N2) virus with a clade 2.3.4.4b HA. We analyzed clinical and epidemiologic data from this patient. Respiratory samples were tested for influenza RT-qPCR assays. Genomic sequence and phylogenetics analyses were performed to provisionally assign a new genotype to the novel HPAI A(H5N2) reassortant virus. The patient presented with fever and tachypnea, later developed hemoptysis and thoracic pain, with oxygen saturation decreasing to 70%. CT scan showed bilateral ground-glass opacities consistent with diffuse alveolar hemorrhage and zones consistent with consolidation. Clinical improvement was observed and the patient was discharged. Through viral complete genome analysis, we identified an HPAI A(H5N2) virus with genes from both clade 2.3.4.4b A(H5N1) viruses similar to those detected in North America during 2022-2023 and genes from the LPAI A(H5N2) viruses detected in Mexico during 2024. This is the first ever laboratory-confirmed human infection caused by an HPAI A(H5N2) virus infection, suggesting a new genotype provisionally classified as B3.14. The relationship of the virus with the severity of illness remains unknown.
. 2026 Mar 9.
doi: 10.1038/s41598-026-41122-0. Online ahead of print.
Emergence of a novel reassorted high pathogenicity avian influenza A(H5N2) virus associated with severe pneumonia in a young adult
Joel Armando Vázquez-Pérez[SUP] 1 [/SUP], Eduardo Becerril-Vargas[SUP] 1 [/SUP], José Ernesto Ramírez-González[SUP] 2 [/SUP], Mario Solís-Hernández[SUP] 3 [/SUP], Charles Todd Davis[SUP] 4 [/SUP], Pamela Garciadiego-Fossas[SUP] 1 [/SUP], Marco Villanueva-Reza[SUP] 1 [/SUP], Hansel Hugo Chávez-Morales[SUP] 1 [/SUP], Enrique Mendoza-Ramírez[SUP] 1 [/SUP], Christian Diego Olivares-Flores[SUP] 1 [/SUP], América Citlali Vera-Jiménez[SUP] 1 [/SUP], Uriel Rumbo-Nava[SUP] 1 [/SUP], Cristóbal Guadarrama-Pérez[SUP] 1 [/SUP], Elio Germán Recinos-Carrera[SUP] 1 [/SUP], Joaquín Zúñiga[SUP] 1 [/SUP], Irma López-Martínez[SUP] 2 [/SUP], Lucía Hernández-Rivas[SUP] 2 [/SUP], Gisela Barrera-Badillo[SUP] 2 [/SUP], Nohemí Colin-Soto[SUP] 5 [/SUP], Laura Flores-Cisneros[SUP] 5 [/SUP], Guillermo Carbajal-Sandoval[SUP] 5 [/SUP], Diana Vidal-Aguirre[SUP] 5 [/SUP], Dayanira Sarith Arellano-Suarez[SUP] 2 [/SUP], Rodrigo Aparicio-Antonio[SUP] 2 [/SUP], Ramiro López-Elizalde[SUP] 6 [/SUP], Carlos Javier Alcazar-Ramiro[SUP] 3 [/SUP], Armando García-López[SUP] 3 [/SUP], Han Di[SUP] 4 [/SUP], Marie Kirby[SUP] 4 [/SUP], Yunho Jang[SUP] 4 [/SUP], Miguel Angel Lezana-Fernández[SUP] 5 [/SUP], Carmen Margarita Hernández-Cárdenas[SUP] 7 8 [/SUP]
Affiliations
- PMID: 41803326
- DOI: 10.1038/s41598-026-41122-0
Infection of backyard and poultry with low pathogenicity avian influenza LPAI A(H5N2) viruses has occurred in Mexico since 1994, and the first human infection caused by this influenza virus was detected in 2024. Since its emergence in the Americas, frequent reassortments between high pathogenicity avian influenza HPAI A(H5N1) and LPAI viruses has occurred. In September 2025, the Instituto Nacional de Enfermedades Respiratorias of Mexico City identified an unsubtypeable influenza A virus infection in a young adult patient later determined to be a reassortant HPAI (H5N2) virus with a clade 2.3.4.4b HA. We analyzed clinical and epidemiologic data from this patient. Respiratory samples were tested for influenza RT-qPCR assays. Genomic sequence and phylogenetics analyses were performed to provisionally assign a new genotype to the novel HPAI A(H5N2) reassortant virus. The patient presented with fever and tachypnea, later developed hemoptysis and thoracic pain, with oxygen saturation decreasing to 70%. CT scan showed bilateral ground-glass opacities consistent with diffuse alveolar hemorrhage and zones consistent with consolidation. Clinical improvement was observed and the patient was discharged. Through viral complete genome analysis, we identified an HPAI A(H5N2) virus with genes from both clade 2.3.4.4b A(H5N1) viruses similar to those detected in North America during 2022-2023 and genes from the LPAI A(H5N2) viruses detected in Mexico during 2024. This is the first ever laboratory-confirmed human infection caused by an HPAI A(H5N2) virus infection, suggesting a new genotype provisionally classified as B3.14. The relationship of the virus with the severity of illness remains unknown.
