Influenza: decrease in cases, symptoms, duration, contagion

[Mise à jour le 25 mai 2022 à 12h06] The flu is a acute respiratory infectiondue to a Influenza virus. It returns each winter and continues in the spring, flattening its patients with more serious cases every year leading to death. What are the flu symptoms ? The incubation period? The disease duration ? Is she contagious ? What are the treatments (natural or medicinal) to heal quickly? When to get vaccinated? Our special file on the flu.

Figures for 2022: how many cases of flu at the moment?

According to the weekly situation update from Public Health France May 25, 2022, the flu epidemic is in sharp decline in France. Flu Indicators continued to decline in mainland France reaching their base levels.

• All regions are in the inter-epidemic phase and all metropolitan areas are green on the map (no alarm).
• The 6 regions that were still in the post-epidemic phase last week moved to the basic level this week.
• Since the start of monitoring, 475 serious cases of influenza admitted to intensive care. No cases admitted in week 20 (from May 16 to 22).

Definition: what is a flu?

The flu is a acute respiratory infectiondue to a influenza virus, while an influenza-like illness can be caused by many other respiratory viruses like rhinovirus, respiratory syncytial virus, etc. Influenza viruses are mainly divided into two types: A and Bdividing themselves into two subtypes (A(H3N2) and A(H1N1) pdm09) or lineages (B/Victoria and B/Yamagata). Type A influenza viruses circulate in many animal species (ducks, chickens, pigs, horses, seals, etc.). Influenza viruses from B-type circulate mainly in humans. Viruses A and B cause seasonal epidemics in humans, but only type A viruses have been responsible for pandemics to date, points out Public Health France.

What are the symptoms of the flu?

Each year, flu epidemics can affect all age groups, but the most vulnerable people are the children under two years old, adults over 65 and people with certain chronic diseases. Early symptoms of the flu include:

• great fatigue,
• chills even when you are not cold,
• a dry, painful cough
• then comes the fever which can rise to more than 39°c,
• aches,
• headaches…

In all cases, in case of sudden aggravation or without improvement of the state 72 hours after the first symptomsit is essential see a doctor.

How many flu deaths?

During the 2021-2022 flu epidemic, Santé Publique France reports 585 deaths with a mention of “flu” of which 14 were under the age of 15, 73 were between 15 and 64 years old and 498 were aged 65 or over. For the 2020-2021 season “the statistical model that allows to estimate the mortality attributable to influenza was not used” has indicated Public Health France. No mortality figures linked to the influenza epidemic have been published. In October 2020, Public Health France reported 3,700 deaths attributable to influenza during the 2019-2020 epidemic with 76% of these deaths involving people over the age of 75, while there are an average of 9,000 deaths each year since 2011. Among the parameters that could explain this lower number of deaths: circulating types of influenza virus during the winter of 2019-2020 (the deadliest virus for the elderly (virus A H3N2) circulated less) and theimprovement of vaccination coverage (from 46.8% in 2018-2019 to 47.8% in 2019-2020).

When to get the flu vaccine?

Vaccination is recommended for people at risk and healthcare professionals, and is the best way to protect against influenza and its complications. It’s necessary allow approximately 15 days between vaccination and the time when the body is protected against the flu. No need to wait for the first cold weather or the start of the epidemic to get vaccinated. The last vaccination campaign ended on February 28, 2022.

The duration of contagion can last 6 days.

How long does a flu last?

A hard flu between 3 and 7 days (5 days on average).

What is the incubation time?

“The incubation time (the time between the moment of illness and the appearance of symptoms) generally lasts between 24 and 48 hours, but it can be extended to 72 hoursrecalls Dr. Parneix. However, the patient is contagious, even before the appearance of symptoms and this, during an average period of 6 days.“

Is the flu contagious?

The flu is a contagious disease. The patient can transmit it “even before the onset of symptoms and during an average period of 6 days“ recalls our interlocutor.

To be infected with the flu virus, you must be in contact with someone who already has the flu. Contamination can occur in three ways:

• The first by airway : a sick person projects droplets of saliva into the air, when talking, coughing or sneezing. Millions of viruses are then found in the air, ready to be inhaled and contaminate you.
• The second, by close direct contact : a sick person shakes your hand or kisses you.
• Finally, contamination can occur through the contact with touched objects by a sick person, for example a doorknob or a telephone.

• Cough at the bend of the elbow and cover the nose when sneezing,
• Wash your hands with soap regularly throughout the day, especially after blowing your nose, coughing or sneezing.
• Blow your nose in a tissue and then throw it in the trash, ideally closed with a lid,
• To carry a surgical mask if you are sick and you have to go to a closed and public place, this prevents contaminating others.
• the hydroalcoholic gel is also practical, but in the long term it can dry out the hands.
• Finally, remember to air the rooms regularly, several times a day: you will thus eliminate stagnant viruses in the air, by sneezing and breathing.

What are the treatments for the flu?

In case of flu-like symptoms:

• Consult the doctor quickly. He or she will be able to make the diagnosis and prescribe the most appropriate medications.
• Take some paracetamol to reduce fever, aches and pains.
• The vitamin C is also sometimes recommended to combat fatigue. Similarly, certain foods are particularly recommended to better combat fatigue.
• If necessary, you can complete with a nasal decongestant and one cough suppressant for dry and stubborn coughs.
• Finally, it is necessary drink plenty and rest.

What are the natural treatments for the flu?

Garlic, lemon, honey, thyme… Several natural solutions can help boost the immune defenses in the prevention or treatment of the flu.

What should I do if my child catches the flu?

To prevent your child from contracting the flu virus, it is important to teach him how to blow his nose in a single-use tissue, to cover his nose to his mouth when sneezing or coughing. In any case, consult your pediatrician so that he can examine him and administer, depending on the case, the most appropriate treatment, especially against fever.

To limit the seasonal flu epidemic, it is essential to adopt simple preventive measures on a daily basis aimed at limiting the circulation of the flu virus, particularly in communities and on public transport where it is easily transmitted. For those around people with the flu, it is recommended to respect these few hygiene rules:

• Wash your hands regularly and systematically after each outing and each contact with the sick person.
• Avoid close contact with the person with the flu and in particular if you yourself are vulnerable or “at risk” (pregnant women, seniors, people suffering from a chronic illness or immunocompromised, young children, etc.)
• Wash yourself regularly hands with soap and water, or if you cannot do otherwise, with a hydro-alcoholic solution, especially after any contact with the patient and after each return home.
• Do not share objects such as glasses, cutlery and of course toothbrushes.
• Ventilate its interior every day between 10 and 15 minutes to renew the air and prevent the proliferation of viruses.
• Clean germ nests such as door handles, remote controls, phone screens…

Thank you to Dr Pierre Parneix, medical officer of health and hospital practitioner in public health (Bordeaux University Hospital).