RESUMO
In October 2022, an outbreak in Europe of highly pathogenic avian influenza (HPAI) A(H5N1) in intensively farmed minks occurred in northwest Spain. A single mink farm hosting more than 50,000 minks was involved. The identified viruses belong to clade 2.3.4.4b, which is responsible of the ongoing epizootic in Europe. An uncommon mutation (T271A) in the PB2 gene with potential public health implications was found. Our investigations indicate onward mink transmission of the virus may have occurred in the affected farm.
Assuntos
Virus da Influenza A Subtipo H5N1 , Vírus da Influenza A , Influenza Aviária , Influenza Humana , Humanos , Animais , Influenza Aviária/epidemiologia , Vison , Virus da Influenza A Subtipo H5N1/genética , Espanha/epidemiologia , Fazendas , Influenza Humana/epidemiologia , FilogeniaAssuntos
Virus da Influenza A Subtipo H5N1 , Vírus da Influenza A , Infecções por Orthomyxoviridae , Animais , Sítios de Ligação , Surtos de Doenças/veterinária , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Virus da Influenza A Subtipo H5N1/genética , Vison/virologia , Ácido N-Acetilneuramínico , Neuraminidase/genética , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/veterináriaRESUMO
Herpes simplex virus (HSV) resistance to acyclovir or foscarnet results from mutations in viral thymidine kinase (TK) and/or DNA polymerase (pol) genes. Replication kinetics and virulence of TK and/or DNA pol clinical mutants were assessed using models of mouse encephalitis and cotton rat genital infection. Replication capacities in Vero cells of a DNA pol altered strain (L850I) and a TK/DNA pol mutant (C467deletion/A912V) were significantly lower than those of unrelated wild-type (WT) strains, while a double DNA pol mutant (S724N/P920S) demonstrated replication kinetics similar to the WT. The replication of a TK-deficient mutant (G439.5addition) was impaired (low m.o.i.) or unaltered (high m.o.i.) compared to that of a WT virus depending on the viral inoculum. Compared to a survival rate of 6% for mice infected intranasally with WT HSV-1 or -2 viruses, G439.5add, C467deletion/A912V and L850I strains were associated with survival rates of 100% (P < 0.05) whereas mice infected with the S724N/P920S mutant had a survival rate of 33% (P = 0.08). Brain viral titers were higher in mice infected with WT HSV-1 or -2 strains and the double DNA pol mutant. All strains except the DNA pol mutant L850I were able to establish latency in the dorsal root ganglia of cotton rats. A good correlation was generally found between replication kinetics of DNA pol mutants and their neurovirulence potential in mice whereas such correlation was not straightforward for TK mutants.