Global flu slows from late December peak
Global flu activity shows more signs of decline after peaking at the end of 2021, the World Health Organization (WHO) said in its latest global flu update, which covers roughly the middle 2 weeks of January.
In the Northern Hemisphere's temperate regions, activity mostly declined, including in North America and Europe, with the H3N2 strain still predominating. However, flu activity continued to rise in China, mainly from the influenza B Victoria lineage.
Transmission persists in some West Asia and North Africa countries, with tropical parts of South America reporting ongoing H3N2 activity and some upticks in the region's temperate countries. In South Asia, some countries are still reporting elevated flu levels, mainly from H3N2.
Globally, of positive flu samples at national labs in the middle of January, 64.6% were influenza A and 35.4% were influenza B. Of the subtyped influenza A samples, 96.8% were H3N2. Of the characterized influenza B samples, all belonged to the Victoria lineage.
In its report, the WHO included its usual caveats that COVID-19 measures and surveillance may be affecting flu activity and reporting, so current patterns should be interpreted with caution. It also continued to urge countries to prepare for managing flu and COVID-19 activity, given that the illnesses occur at the same time.
Feb 7 WHO global flu update
UK probes imported Lassa fever cases
Health officials in the United Kingdom today reported two confirmed Lassa fever cases, plus an additional probable infection, all in the same family who had recently traveled to West Africa.
In a statement, Susan Hopkins, MB BCh, chief medical advisor with the UK's Health Security Agency (HSA) said the virus that causes Lassa fever doesn't spread easily among people, and the risk to the public is very low. Health officials are identifying contacts of the patients for assessment and support.
Since 1980, Britain has reported eight imported Lassa fever cases, most recently two cases in 2009. The HSA said there was no onward transmission in any of the cases.
Lassa fever is typically spread by rodents, though human-to-human transmission can occur through contact with the body fluids of infected patients. West Africa reports about 100,000 to 300,000 Lassa fever cases each year, and about 5,000 cases are fatal.
The United States has reported similar sporadic imported cases, the last one in 2015, which involved a man in New Jersey who died from his illness.
Feb 9 HSA statement
May 26, 2015, CIDRAP News story