Influenza Season 2015 Has Arrived

 Every year during the winter months between May and August, South Africa experiences an increase in influenza (commonly known as flu) circulation.
 
There are several different strains of flu which may circulate each year. One of these is called Influenza A(H1N1)pdm09. This is the strain which is sometimes referred to as swine flu and caused the 2009 influenza pandemic. Currently in 2015, this strain of flu behaves just like any other normal seasonal flu strain. The clinical presentation, severity and management of influenza A(H1N1)pdm09 is the same as for seasonal flu. Identification of patients with this strain during this influenza season should be treated as any other seasonal flu case. There are no specific public health interventions recommended for this strain.

In the majority of people flu is an uncomplicated illness lasting 3-7 days. The illness is characterised by sudden onset of constitutional and respiratory symptoms such as fever, body pains, cough, sore throat, runny nose and headache. However, flu can cause serious illness in some people leading to hospitalisation and even death. People at increased risk of developing severe influenza include pregnant women, young children, the elderly, and people with certain health conditions, such as heart, lung or kidney disease, nervous system disorders, or a weakened immune system. Flu vaccination is especially important for these people. Data from South Africa estimates that approximately 10 000 people die on average of seasonal flu-related illness every winter.

Flu vaccine remains the primary means for preventing seasonal flu infection. Flu viruses are always changing therefore each year’s flu vaccine is made to protect against three viruses that are likely to cause disease that specific year. This is based on data collected from global influenza surveillance. The 2015 flu vaccine protects against Influenza A(H1N1)pdm09. . Flu vaccine cannot prevent all cases of influenza, but it is the best defence available against the disease. Vaccines should be given sufficiently early to provide protection for the winter, though it is never too late to vaccinate. A protective antibody response takes about 2 weeks to develop.
 
The 2015 influenza vaccine has been available in South Africa since the end of April (later than expected due to delays in southern hemisphere vaccine production) and could be accessed at public health sector clinics and private healthcare providers (pharmacies and private practitioners etc.). This implies that people got vaccinated later we could be expecting more seasonal influenza cases country-wide.
 
The Department’s Influenza Vaccination Programme targets the following high risk individuals that present to our public health facilities:

1.  Adults and/or children at high risk for flu-related complications because of underlying medical conditions including

• Chronic pulmonary disease (including asthma)
• Cardiovascular disease (except hypertension)
• Renal, hepatic, neurological and haematological disorders
• Metabolic disorders (including diabetes mellitus)
• Morbid obesity (BMI≥40)
• Immunosuppression (including HIV-infected persons with CD4 counts over 100/mm3

2. Pregnant Women (all stages of pregnancy)
3. Children aged 6 months to under 5 years (59 months)
4.  Residents of old-age (nursing) homes and other chronic care or rehabilitation centres
5. Children aged 6 months to 18 years on long-term aspirin therapy
6.  All persons aged 65 years and older

 
Members of the public are encouraged to be vaccinated to protect themselves, families, their children, colleagues from influenza. Vaccination for these individuals/ members of the public is not covered by the Department of Health’s Influenza Vaccination Programme, and could be accessed through the private sector. Most medical aids will pay for influenza vaccinations.  
Because influenza is highly contagious, being spread by respiratory droplets (from sneezing and coughing), by touching surfaces that other people have touched and touching other people, it can spread easily especially in closed communities (like schools, work place and institutions). General preventative precautions should be taken - such as hand washing, cough hygiene and avoiding contact with people who are ill should also be considered.
 
Frequently Asked Questions
 
What is influenza?
Influenza also called flu is an acute viral respiratory infection, transmitted by the influenza virus. This virus has three main types A, B and C. Influenza A is classified into different subtypes. The currently circulating seasonal viruses are A (H1N1), influenza A (H3N2) and influenza B viruses. The flu viruses are typically in circulation in the winter months in South Africa with an average start of the first week of June, although this varies.

How do you get flu?
The flu virus spread mainly by droplets made when people with flu cough, sneeze or talk. These droplets can land in the mouths or noses of people who are close by. You can also catch flu by touching a surface or an object that has flu virus on it and then touching your mouth, eyes or nose.
 
How long is a person with influenza contagious?
People with flu may be able to pass on the flu to someone else before they know that they are sick, as well as while they are sick. A person with flu may be contagious 1 day before symptoms appear and for 3-7 days after the onset of symptoms. Some people, especially young children and people with weakened immune systems, maybe be able to infect others for an even longer time
 
How soon will I get sick if I am exposed to the flu?
The time from when a person is exposed to flu virus to when symptoms begin is about 1 to 4 days, with an average of about 2 days.

What are the signs and symptoms of influenza?

• Sudden onset of fever
• Acute upper respiratory symptoms: dry cough, sore throat
• General symptoms: malaise, headache, fatigue, muscle pain and body aches , cold shivers and hot sweats
• Some people may have vomiting and diarrhoea, though this is more common in children than adults.

 
What are the possible complications?
While most influenza illness is mild, complications (particularly pneumonia) are always a concern in persons with underlying conditions or certain risk factors.

• Complications within the chest are usually characterised by: shortness of breath at rest or during usually tolerated activity, chest pain, low blood pressure, clinical or X-Ray features of pneumonia and myocarditis.
• Complications involving other organs: ear infections, sinus infections, encephalitis, severe dehydration, renal failure and multiple organ failure.
• Worsening of underlying conditions such as: asthma, Chronic Obstructive Pulmonary Disease (COPD), diabetes, hypertension, renal or liver insufficiency, Congestive Cardiac Failure (CCF) and other cardiovascular diseases.

Who is at risk of developing complications?

• Pregnant women, and including the 2 week period after delivery
• Young children (<2 years old)
• Elderly people (>65 years of age)
• People with existing chronic diseases (heart, lung, kidney, endocrine) for example diabetes or asthma, persons who are immunosuppressed
• Morbidly obese people (BMI ≥40 or BMI≥35 with obesity related health conditions)
• People ≤18 years of age receiving chronic aspirin therapy

 
How safe is the vaccine?
The vaccine cannot result in influenza infection as there is no live virus contained within the vaccine. Some persons experience mild fever and local pain at the injection site. Overall the vaccine has an excellent safety record.

How do you prevent the spread of flu?

• Infected people should stay at home and try to limit contact with other people
• Cover nose and mouth with a tissue when coughing or sneezing and throw away used tissue in bin
• Wash hands often with soap or use an alcohol based hand rub, especially after coughing, sneezing, or blowing the nose
• Surfaces that are commonly touched should be cleaned and disinfected.

 
How do you treat flu?
Most of the treatment is generic and involves symptom relief unless the individual is very sick or is at risk of developing complications (see ‘Who is at risk of developing complications?’). If you fall onto this category then you need to see a doctor as you may need to take antiviral medication.
For uncomplicated cases at low risk then the prevention of further spread and the following measures are advised:

• Bed rest
• Drink plenty of water and other clear fluids
• Symptomatic treatment for cough, fever, nasal congestion, etc.

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Antiviral agents such as Tamiflu are recommended for persons at risk of complications. Antiviral agents are not generally prescribed for contacts of persons with influenza as a preventative measure. Routine laboratory testing of patients with influenza illness is not required.