Varough M. Deyde, etc.,al. Surveillance of Resistance to Adamantanes among Influenza A(H3N2) and A(H1N1) Viruses Isolated Worldwide. The Journal of Infectious Diseases 2007;196:249
Our previous reports demonstrated an alarming increase in resistance to adamantanes among influenza A(H3N2) viruses isolated in 2001–2005. To continue monitoring drug resistance, we conducted a comprehensive analysis of influenza A(H3N2) and A(H1N1) viruses isolated globally in 2005–2006. The results obtained by pyrosequencing indicate that 96.4% (n = 761) of A(H3N2) viruses circulating in the United States were adamantane resistant. Drug resistance has reached 100% among isolates from some Asian countries. Analysis of correlation between the appearance of drug resistance and the evolutionary pathway of the hemagglutinin (HA) gene suggests at least 2 separate introductions of resistance into circulating populations that gave rise to identifiable subclades. It also indicates that resistant A(H3N2) viruses may have emerged in Asia in late 2001. Among A(H1N1) viruses isolated worldwide, resistance reached 15.5% in 2005–2006; in the United States alone, it was 4.0%. Phylogenetic analysis of the HA and M genes indicates that the acquisition of resistance in A(H1N1) viruses can be linked to a specific genetic group and was not a result of reassortment between A(H3N2) and A(H1N1) viruses. The results of the study highlight the necessity of close monitoring of resistance to existing antivirals as wells as the need for new therapeutics.
See Also:
Latest articles in those days:
- Influenza D Virus Infection in China, 2022-2023 5 hours ago
- Evidence of reassortment of avian influenza A (H2) viruses in Brazilian shorebirds 5 hours ago
- Epitopes in the HA and NA of H5 and H7 avian influenza viruses that are important for antigenic drift 2 days ago
- Assessment of CD8+ T-cell mediated immunity in an influenza A(H3N2) human challenge model in Belgium: a single centre, randomised, double-blind phase 2 study 2 days ago
- Dual N-linked glycosylation at residues 133 and 158 in the hemagglutinin are essential for the efficacy of H7N9 avian influenza virus like particle vaccine in chickens and mice 2 days ago
[Go Top] [Close Window]
