Everything you need to know about the flu in children – Symptoms, complications, treatment and prevention

The beginning of the year has brought thousands of presentations to hospital emergency rooms in Romania, with pediatric and infectious disease units being the most crowded. An insufficiently developed immune system and the airborne mode of transmission within communities are the reasons for a higher prevalence of respiratory viruses among children. Flu in children is a viral disease that most frequently occurs between December and March, thus having a pattern that is termed "epidemic".

In what follows, you will find all the necessary information about this respiratory virus: what it is, how it appears, how it is transmitted, how it is diagnosed, what complications may arise, how we treat it, and most importantly, how we prevent infection.

Table of contents

1. What is the flu?
2. Causes of the flu
3. How is it transmitted?
4. Which children are more exposed to infection?
5. What are the symptoms?
6. When should we see a doctor?
7. What investigations are necessary?
8. Complications of the flu
9. Treatment of the flu
10. How do we prevent illness?

What is the flu?

The flu is a highly contagious viral infection caused by influenza viruses (types A, B, or C). Of the three, only viruses A and B are those that can cause clinically significant pathology, causing seasonal epidemics annually, while influenza virus C causes a mild form of the disease.

Causes of the flu

Due to sudden temperature changes and the appearance of influenza viruses during the winter period, the immune system is more vulnerable, which leads to easier infection of the body.

How is it transmitted?

The influenza virus enters through the nose, mouth, or eyes, potentially reaching the lungs, where it multiplies. It is easily transmitted through aerosols (coughing or sneezing), but also through direct contact with contaminated surfaces (desks, chairs, pencils, phones, toys, door handles, towels, eating utensils, etc.). It has been proven that it can live for 1-2 days on surfaces, 5 minutes on the skin and 15 minutes on paper. For this reason, children are the most prone to being infected and further transmitting this virus. Statistically, a sick person will infect between 1-3 healthy people.

The infected person is contagious 2 days before the onset of the first symptoms and 5 days after the onset of the disease. Usually, the risk of infecting others disappears around the seventh day of illness.

Which children are more exposed to infection?

A child is more exposed to infection if:

• They are under 2 years old;
• They have cardiovascular, respiratory, hematological, renal, neurological, metabolic, or oncological conditions, or a weakened immune system;
• They are around infected people;
• They do not follow the hygiene standards necessary to prevent illness;
• They have not been immunized with the flu vaccine.

What are the signs and symptoms?

Flu symptoms appear suddenly and violently, usually 2 days after infection, and can be the following:

• High fever, 39-40°C;
• Chills;
• Headache;
• Myalgia (muscle pain);
• Dysphagia (sore throat);
• Stuffy or runny nose;
• Dry cough that can turn into a productive one;
• Severe fatigue;
• Lack of appetite.

In the case of newborns and infants, nonspecific symptoms such as vomiting and diarrhea or abdominal pain may occur, which may indicate a bacterial infection instead.

The symptoms last on average 3-4 days, with the cough potentially persisting for 1-2 weeks.

The signs and symptoms that more easily differentiate the flu from the common cold are the following:

When should we see a doctor?

When symptoms appear, it is recommended that you contact your family doctor or pediatrician and follow their recommendations before the actual consultation. Children under 5 years old, especially those under 2, and chronic patients must be examined by a doctor.

In the following cases, an emergency medical evaluation of the child is necessary:

• They show respiratory distress (difficulty breathing, rapid and wheezing breathing);
• Their general state is altered;
• They are not alert, they do not interact;
• Chest pain;
• Cyanosis (bluish tint) of the lips or face;
• They have vomiting;
• They refuse liquids and show signs of dehydration (dry mucous membranes, absence of tears, sunken eyes, decreased frequency of urination);
• The temperature remains high after administering antipyretics or they have seizures;
• Severe muscle pain (the child refuses to walk);
• Dizziness, confusion.

What investigations are necessary to make a diagnosis?

The doctor will take a medical history, asking about the child's symptoms and health history, and will then physically examine them. Usually, the flu in children is easily differentiated from other viruses by specific symptoms.

However, some paraclinical (laboratory) tests can be performed, such as:

• Complete blood count;
• ESR, Fibrinogen, C-reactive protein;
• Chest X-ray (to exclude the diagnosis of pneumonia);
• Qualitative screening test, necessary for detecting the presence of Influenza A and B viruses (by collecting nasal secretions or nasopharyngeal aspirate): it is recommended to be done within 4 days of symptom onset.

Complications of the flu

If not treated in time, the flu can evolve unfavorably, leading to:

• Pneumonia;
• Acute laryngitis;
• Laryngotracheobronchitis;
• Acute bronchiolitis;
• Exacerbation of bronchial asthma;
• Otitis media;
• Sinusitis.

Treatment of the flu

Do not give the child medication without first consulting a doctor. Monitor their health status and contact the doctor if symptoms worsen or if complications arise.

Being a viral infection, the administration of antibiotics is contraindicated. These may only be necessary in case of a secondary bacterial infection diagnosed by the doctor.

The following are recommended:

• Isolation of the child at home, with bed rest;
• Hydration;
• A diet rich in Vitamin C;
• Alleviating pain and lowering temperature using analgesics/antipyretics/anti-inflammatories (paracetamol and/or ibuprofen; aspirin is contraindicated for children under 16 due to the possibility of Reye's syndrome, a rare and severe condition that mainly affects the brain and liver);
• Nasal decongestion using saline, seawater, drops, or nasal sprays with decongestants; additionally, it may be necessary to aspirate nasal secretions using a bulb syringe or nasal aspirator;
• Administration of orodispersible tablets to hydrate the throat, and cough suppressants;
• Treatment of vomiting and diarrhea;
• Antivirals (based on oseltamivir) will be administered only based on a doctor's recommendation and prescription after evaluating the patient (these are much more effective if administered within the first 48 hours of symptom onset).

How do we prevent the flu in children?

Vaccination is the primary means of preventing the flu in children and its complications. Since the viruses that cause seasonal flu mutate from one season to the next, annual vaccination is necessary. The peak of the flu season is usually between December and February, but cases are present both before and after, potentially being reported even in April. Considering that immunity is gained in 2-3 weeks, it is advisable that vaccination be done as early as possible (late September – early October). In exceptional cases, it can also be done in the spring.

People who should be prioritized for vaccination, according to the World Health Organization:

• Children older than 6 months (if they are under 9 years old and have not been vaccinated previously, 2 doses of the vaccine should be given, one month apart);
• Pregnant women (in this way, after birth, generally, babies up to 6 months will be protected);
• Seniors over 60 years old;
• Those with chronic diseases.

Who should not be vaccinated or must first ask for medical advice:

• Children under 6 months;
• People with severe allergies to the vaccine or vaccine components;
• Those who have a moderate to severe illness, with or without fever (they should wait until they recover to be vaccinated);
• People with a history of Guillain-Barré syndrome (a severe paralytic disease).

Children aged between 6 months and 5 years and those in institutions will receive the vaccine 100% subsidized.

The greatest vulnerability is held by children under 6 months who cannot be vaccinated. They can be protected by vaccinating all persons who come into contact with them and by following hygiene rules.

Since the community is the place where most infections occur, certain measures of personal and space hygiene where activities take place must be taken:

• Hand hygiene: hands must be washed frequently (at least 20 seconds) and/or disinfected (before entering the classroom, before meals, after using the restroom, after coughing/sneezing, and whenever necessary);
• Respiratory hygiene: children will sneeze/cough into a disposable tissue or into the crook of the elbow, then immediately throw the tissue in the trash and wash/disinfect;
• Classroom hygiene: classrooms or other spaces frequented by children will be aired frequently (at least 10 minutes), and surfaces will be cleaned and disinfected before use;
• Exchanges of personal items and touching the eyes, nose, and mouth with dirty hands will be avoided;
• Wearing a mask in closed and crowded spaces is also recommended;
• In case of illness, entering the community again will be avoided.

Regarding the choice of antiseptic and disinfectant products for preventing influenza virus infections (or other viruses and bacteria), in the Klintensiv portfolio you will find a multitude of effective products in the form of solutions, gels, or wipes, including products used for nebulization.

Conclusion

The flu is one of the most common respiratory infections, which, against the background of an incompletely developed immunity such as that of children, or in the presence of chronic diseases, can lead to complications that require hospitalization. To avoid this, we need to know what measures to take to protect ourselves and our children. In case of illness, it is advisable to contact the family doctor or pediatrician who will decide the next steps (a check-up for a correct examination and the recommendation of a treatment).

Bibliography:

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