Flu

Flu is transmitted from an ill person to another person through droplets expelled when coughing and sneezing. The transmission period starts from the day before symptoms appear and persists for five days afterwards.  

It is estimated that seasonal flu may affect between 5% and 20% of the general population, and that approximately 25% of febrile respiratory processes may be produced by the flu. This increased morbidity gives rise to a large number of medical consultations and absences from work as a consequence of the disease. Moreover, some people, such as older people, those with chronic illnesses, immuno-suppressed people and pregnant women, among others, may suffer more from the illness and it is common for them to experience complications during its evolution. Flu thus continues to be a major public health issue.

Symptoms 

Flu presents heightened fever, dry cough, headache and neck ache, muscle pain and general illness. It can also cause diarrhoea, nausea and vomiting, especially in young children. In most cases, people recover in 7-10 days.

Who is affected by the condition?

Flu may affect anyone, but the most vulnerable to suffering complications are children under the age of 2, people aged 60 or above, pregnant women, morbidly obese people and people of any age who suffer from one of the following types of illness: cardiovascular, pulmonary (including bronchopulmonary dysplasia, cystic fibrosis and asthma), neurological, neuromuscular, metabolic (including diabetes mellitus), kidney failure, immunosuppression, cancer, chronic liver diseases, asplenia and iron deficiencies.   

Diagnosis

Flu diagnosis is normally clinical and does not require laboratory tests. Despite that fact, microbiological diagnosis is fundamental to be able to obtain aetiological confirmation in patients with risk factors and those with serious illnesses. The detection of the virus in respiratory samples can be done using cultures, antigen detection techniques and molecular methods.

Typical treatment

There is no specific treatment for flu. Treatment with analgesics and antipyretics (paracetamol) is recommended to alleviate or treat some of the symptoms associated with flu, such as fever or headache.

Antibiotics do not cure the flu. Only in cases where there is an overlying bacterial infection, such as pneumonia, or in those with chronic illnesses, may preventive antibiotic treatment be indicated to avoid complications.

Antivirals, such as oseltamivir or zanamivir, may be indicated in people at high risk of complications to reduce the duration of the flu and the possibility of complications, but they should begin to be taken within 48 hours from the outbreak of symptoms.

Prevention

The best way of protecting yourself from the flu is vaccination and following good hygiene practices to prevent the spread of the virus. The purpose of anti-flu vaccination each year is to generate protection against the flu viruses that circulate in the flu season. Health authorities and scientific associations around the world unanimously recommend seasonal anti-flu vaccination for people at high risk.  Anti-flu vaccinations are very safe and well-tolerated with effectiveness that ranges from 30% to 70% to prevent hospitalisation due to flu and pneumonia. In older people living in institutions, vaccinations have proven to be between 50% and 60% effective to prevent hospitalisation or pneumonia, and 80% to prevent death by flu.