25 May 2011
The annual influenza season has started with cases being reported since the first week in May and a sharp rise in the past week. Although this is unusually early for influenza it does not necessarily mean it will be a severe season. To date the predominant strain is Influenza A H1N1 which after the 2009 pandemic has become a regular seasonal influenza strain. Influenza in South Africa is monitored through the National Viral Watch Programme at the National Institute for Communicable Diseases a division of the National Health Laboratory Service.
The symptoms of influenza include sudden onset of fever, dry cough, muscle pain, cold shivers and sweats and is often confused with the common cold. Most people ill with influenza will recover without complications. We need to be especially alert in high- risk groups as influenza may cause severe illness including pneumonia in pregnant women, persons older than 65 years, those with chronic lung disease, heart disease, diabetes and those whose immunity is suppressed due to HIV and other causes.
Treatment with an effective antiviral drug should be started as early as possible for those in the risk group even with mild influenza-like illness, but also in any person with influenza whose condition worsens.
Of concern is the late diagnosis or misdiagnosis, and hence delayed treatment of severe influenza in pregnancy, particularly in the third trimester and immediate post-delivery period.
The virus is airborne and can be spread through the air by coughing and sneezing. It can also be contracted by touching surfaces contaminated by saliva and secretions of infected people so it is important to practice good hand hygiene as well as coughing and sneezing etiquette.
Ideally those in the risk group should already have been vaccinated since the vaccine takes 10-14 days to be effective and the influenza season is well underway. However the vaccine should still be considered for persons at risk for complications of influenza. The vaccine is considered safe with few side effects, but is only effective against the influenza virus and not the many other causes of respiratory illness. The vaccine is still available at pharmacies and clinics and any person in a risk group who has not yet been vaccinated should do so as soon as possible.
This advisory is issued by the National Institute for Communicable Diseases, a division of the National Health Laboratory Service.
For more information please contact Nombuso Shabalala on 011 555 0545 or 082 886 4238.