Pandemic risk characterisation of zoonotic influenza A viruses using the Tool for Influenza Pandemic Risk Assessment (TIPRA).

A systematic risk assessment approach is essential for evaluating the relative risk of influenza A viruses (IAVs) with pandemic potential. To achieve this, the Tool for Influenza Pandemic Risk Assessment (TIPRA) was developed under the Global Influenza Programme of WHO. Since its release in 2016 and update in 2020, TIPRA has been used to assess the pandemic risk of 11 zoonotic IAVs across ten evaluation rounds.

United States Centers for Disease Control and Prevention support for influenza surveillance, 2013-2021.

Objective: To assess the stability of improvements in global respiratory virus surveillance in countries supported by the United States Centers for Disease Control and Prevention (CDC) after reductions in CDC funding and with the stress of the coronavirus disease 2019 (COVID-19) pandemic.

Methods: We assessed whether national influenza surveillance systems of CDC-funded countries: (i) continued to analyse as many specimens between 2013 and 2021; (ii) participated in activities of the World Health Organization's (WHO) Global Influenza Surveillance and Response System; (iii) tested enough specimens to detect rare events or signals of unusual activity; and (iv) demonstrated stability before and during the COVID-19 pandemic. We used CDC budget records and data from the WHO Global Influenza Surveillance and Response System.

Global update on the susceptibilities of human influenza viruses to neuraminidase inhibitors and the cap-dependent endonuclease inhibitor baloxavir, 2018-2020.

Global analysis of the susceptibility of influenza viruses to neuraminidase (NA) inhibitors (NAIs) and the polymerase acidic (PA) inhibitor (PAI) baloxavir was conducted by five World Health Organization Collaborating Centres for Reference and Research on Influenza during two periods (May 2018-May 2019 and May 2019-May 2020). Combined phenotypic and NA sequence-based analysis revealed that the global frequency of viruses displaying reduced or highly reduced inhibition (RI or HRI) or potential to show RI/HRI by NAIs remained low, 0.5% (165/35045) and 0.

A second external quality assessment of isolation and identification of influenza viruses in cell culture in the Asia Pacific region highlights improved performance by participating laboratories.

Influenza viruses must be amplified in cell culture for detailed antigenic analysis and for phenotypic assays assessing susceptibility to antiviral drugs or for other assays. Following on from the first external quality assessment (EQA) for isolation and identification of influenza viruses using cell culture techniques in 2016, a follow up EQA was performed in 2019 for National Influenza Centres (NICs) in the World Health Organization (WHO) South East Asia and Western Pacific Regions. Nineteen WHO NICs performed influenza virus isolation and identification techniques on an EQA panel comprising 16 samples, containing influenza A or B viruses and negative control samples.

Global update on the susceptibilities of human influenza viruses to neuraminidase inhibitors and the cap-dependent endonuclease inhibitor baloxavir, 2017-2018.

The global analysis of neuraminidase inhibitor (NAI) susceptibility of influenza viruses has been conducted since the 2012-13 period. In 2018 a novel cap-dependent endonuclease inhibitor, baloxavir, that targets polymerase acidic subunit (PA) was approved for the treatment of influenza virus infection in Japan and the United States. For this annual report, the susceptibilities of influenza viruses to NAIs and baloxavir were analyzed.