The World Well being Group (WHO) regional places of work and member states, in collaboration with its International Influenza Surveillance and Response System (GISRS), collate and report knowledge on influenza exercise worldwide each two weeks.
Nationwide Influenza Centres (NICs) and different nationwide influenza laboratories from 105 international locations, areas, or territories report knowledge to FluNet.
The newest report up to date as much as 30 October 2022 has knowledge categorized by influenza transmission zones, i.e., international locations/areas with comparable influenza transmission patterns.
As well as, it covers epidemiological and virological FluNet knowledge for the interval between 17 October 2022 and 30 October 2022. Throughout this time, the WHO GISRS laboratories examined over 229,940 specimens.
Key highlights
Influenza exercise elevated globally, and particularly influenza A(H3N2) virus subtype turned predominant. Of 229,940 specimens examined, 15,723 had been constructive for influenza viruses. The share of influenza A and influenza B viruses was 14,589 (92.8%) and 1134 (7.2%). Whereas all characterised B viruses belonged to the B/Victoria lineage, 1424 (21.2%) and 5284 (78.8%) of 14,589 influenza A viruses had been H1N1 and H3N2, respectively.
On the hemispherical stage, whereas the upward pattern in influenza exercise continued within the northern hemisphere, it plateaued within the southern hemisphere. Primarily based on this commentary, the WHO beneficial that Northern hemisphere international locations, together with the USA and Canada, step up their influenza vaccination marketing campaign to forestall hospitalizations and deaths. Extra importantly, medical docs ought to display screen or take a look at folks for influenza and deal with them per nationwide steering.
Regardless of a pointy enhance in COVID-19 exercise within the WHO Area of the Americas and a slight enhance in South-East Asia and Western Pacific Areas, sentinel surveillance outcomes confirmed it remained underneath 10% following a long-term downward pattern starting in mid of 2022.
Thus, the WHO inspired stepping up built-in surveillance for influenza and extreme acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in international locations harbored within the northern hemisphere. They particularly targeted on international locations which have acquired the multiplex influenza and SARS-CoV-2 reagent kits from GISRS. The WHO even revealed revised interim steering for these international locations emphasizing the pressing have to report epidemiological and laboratory info on time to their regional and international platforms.
Temperate-zone international locations (Northern Hemisphere)
In international locations of the temperate zone of the Northern hemisphere, such because the US and Canada, influenza-like sickness (ILI) and respiratory syncytial virus (RSV) exercise elevated above the seasonal common for this time of yr, with influenza A(H3N2) virus being predominant. SARS-CoV-2 continues to be the causal agent behind above-the-epidemic threshold mortality within the USA.
Influenza A(H3N2) predominated in European international locations, with the best ILI exercise reported in South West Europe (3.62% positivity). Portugal, adopted by Germany and Spain, reported an growing pattern in ILI exercise. RSV exercise was the best in France and constantly growing. Likewise, extra mortality throughout most age teams continued to surge in European international locations. The Central (e.g., Kazakhstan) and West Asian international locations, like Saudi Arabia, reported excessive/elevated ILI exercise, with B-lineage influenza viruses predominating in Kazakhstan. Quite the opposite, in East Asia, influenza A(H3N2) exercise remained steady at intermediate ranges.
Temperate zone international locations (Southern Hemisphere)
The general ILI exercise appeared to lower on this reporting interval, besides in South America, the place ILI exercise elevated in a number of international locations, corresponding to Argentina, Chile, and Uruguay. In Chile and Uruguay, influenza A(H3N2) viruses predominated, whereas influenza B and influenza A(H1N1) had been predominant in Argentina. Throughout all Pacific Islands, together with New Zealand, ILI exercise remained low besides in a number of international locations. Likewise, in Australia, ILI exercise remained minimal, although testing detected influenza A(H1N1), influenza A(H3N2), and a few B viruses.
Tropical international locations
The tropical international locations of South America and Africa had low ILI exercise in the course of the examine reported interval. Notably, RSV exercise elevated solely in Brazil. In Puerto Rico and Guatemala, elements of the Caribbean, and Central America, ILI exercise was above the common for this time of yr and the seasonal threshold.
