Flu Update 6 January 2014

Over the past week flu activity has continued to increase to across the United States. There are now 25 states in the US which are reporting widespread levels of flu activity. The dominant flu this season’s VH1 in one virus which reached epidemic proportions during 2009. During the 2009 flu season VH1 in one virus can an estimated 284,000 people worldwide according to CDC estimates.

20 states in the US are now experiencing high influenza activity. This is an increase from six states that were reporting high influenza activity the previous week. 20 states are reporting what is termed a regional level of influenza activity and three states are reporting a local level of influenza. The number of states predicted to report a high level of influenza activity is expected to increase in the following weeks, as the H1N1 virus continues to spread.

During the current flu season influenza A, influenza H1N1, and influenza B virus have all been identified. Of the 922 influenza a virus cases that have been identified, currently 99.2% of them were the H1N1 virus. During the previous week two children died as a result of influenza. One of these deaths was as a result of H1N1 virus and the other was for influenza A virus. The specific subtype of the influenza A virus has not yet been determined.

Since the beginning of flu season 1,583 people have been hospitalised for influenza. This week influenza caused 5.8 people to be hospitalised for every 100,000 people in the United States. As of the last week the number of deaths attributed to influenza remained below the levels to classify this flu season as an epidemic.

Between December 22 and 28 the number of people seeking health care for the influenza illness increased dramatically. The flu is now above the baseline for the fifth consecutive week. In the 10 different regions that the CDC measures influenza illnesses are now above the baseline measure for those regions. The World Health Organization collects respiratory samples in all 50 States in the US. Of the 6419 specimens that were tested 26.7% or 1711 cases tested positive for influenza. Of these 97.4% tested positive for the influenza a virus. 2.6% tested positive for the influenza B virus.

In the previous flu season H3N2 was the dominant influenza strain. This strain of influenza tended to cause death and older people. In contrast the H1N1 virus is more likely to result in deaths of young children and middle-aged adults. The flu vaccine that has been offered by the Centre for disease control offers good protection against the H1N1virus. It is also worth noting that the H1N1 influenza strain appears not to have developed resistance to anti-viral drugs including Tamiflu. There are specific groups of people that are considered to be high risk for the H1N1 virus for the 2014 flu season. These include people with health problems including diabetes, heart problems and asthma. Very old and young people are also at higher risk due to the H1N1 virus.

25 states are reporting what is called widespread geographic influenza activity. This is a measurement of the spread of the influenza but does not refer to the level of intensity of the influenza. In Rhode Island and Hawaii there are reports of sporadic influenza activity.

Guam and the US Virgin Islands are currently the only territory’s part of the United States that have not reported any cases of influenza. Even Puerto Rica is reporting what is termed a local level of influenza activity. In North Carolina 13 people have died during the current flu season according to the Department of Health and Human Services. In Hidalgo County Texas there were six deaths, and in Salt Lake City two people have died.

Currently the flu season has been centred around South, but in the last week the flu has moved nationwide and cases of influenza have been reported in all states according to the Centre for disease control and prevention. The Centre for disease control and prevention predicts that in the following weeks flu activity will continue to increase. The CDC recommends that anyone who is six months or older and has not yet received a flu vaccination for this season should get one. The CDC has stated that anti-viral drugs for the H1N1 virus are most effective when taken with two days of contracting the flu.

Read more about the flu symptoms 2014.