Most indicators show that flu activity is starting to decrease across the UK.  The estimated cases self referring to the National Pandemic Flu Service have shown decreases in all areas, although there is a slight exception of a very minor increase in the 1-4 year age group.

Health Protection Agency (HPA) modelling gives an estimate of 22,000 new cases in England last week (with a modelling range of 11,000 to 47,000), which represents a significant decrease from the previous week.

To date (as of 2 December 2009) 4,002 viruses have been analysed by the HPA Centre for Infections for the genetic marker commonly associated with resistance to Oseltamivir ("Tamiflu").  To date, twenty-four viruses have been found to carry the marker in the UK with three, through additional testing, showing evidence of resistance when viral growth is tested in the presence of Oseltamivir.  The viruses are still sensitive to Zanamivir ("Relenza").

Information on medical history in potential cases of resistance was available for 17 cases, all of whom had an underlying medical condition.  Fourteen were immuno-suppressed and three had chronic respiratory or neurological illnesses.  Further testing of the samples have shown the antiviral resistance in fourteen of the cases was treatment-induced, four were probably acquired through person-to-person transmission, and in four cases the origin of the resistant virus is still under investigation.  There have been no significant changes in the virus.

Globally, tropical regions are experiencing variable rates and intensity of influenza transmission, but low levels in tropical regions of Americas and Asia.  Most countries of the tropical regions of Central and South America continue to report declining influenza activity, with the exception of Ecuador and Venezuela.

Increasing disease activity and pandemic influenza virus isolation continues to be reported in several countries in Central and Western Asia and the early arriving winter influenza season continues to intensify across parts of North America and much of Europe.

In North America and a limited number of European countries there are signs that disease activity has peaked, although very high activity is still being seen in Sweden, Norway, Moldova and Italy.

With regard to vaccines, early indications of the immune response of the vaccines are encouraging.  Side effects are very minor, mainly limited to slight arm soreness.  Reports of [post-vaccination Guillain Barre Syndrome (generally associated as a risk of vaccination in the media) are currently lower than normal background rates (the level of cases normally presenting when no vaccine campaign is being conducted).

There have been no reported deaths attributed to the vaccination, nor have there been any notable negative effects among pregnant women who have been vaccinated.