Flu in children

Children often get colds at least 6-7 times a year. In the first year of kindergarten, children have a 50% higher incidence of disease than children who are cared for at home.

Flu is a viral disease with symptoms such as runny or stuffy nose, accompanied by systemic symptoms and other symptoms such as muscle pain and fever that may not be present or appear mild. The disease is often called rhinitis, but it is related to the lining of the sinuses, so it is also called rhinitis-sinusitis. The most common pathogen is rhinovirus, but it can also be caused by many other viruses.

Flu often happens in the cold season

The flu occurs all year round but the frequency of the disease is highest from the beginning of autumn to the end of spring, reflecting seasonal virus infection with the clinical situation of the flu. The frequency of colds is highest in early autumn (August to October) and around the end of spring (April to May). Seasonal parainfluenza infection is highest in the late fall, if the syncytial virus (RSV) and influenza virus are highest in December to April.

Children often get flu 6-7 times a year, with about 10-15% of children get the flu more than 12 times a year. The frequency of colds decreases with age, adults only get flu 2-3 times / year. In the first year of kindergarten, children have a 50% higher incidence of illness than children who are cared for at home. However, the incidence of illness in younger groups decreases with the time children are cared for in daycare centers.

Transmission of influenza virus

Flu viruses are often transmitted by small aerosols, large aerosol particles or through direct contact. Although the pathogenesis of flu in general is transmitted by the above mechanisms, each virus still has its own route of transmission. Studies of rhinovirus and RSV have shown that they have the main route of exposure, though still transmitted through large aerosols. Unlike the rhinovirus and RSV, influenza viruses are usually transmitted through small aerosols.

Respiratory viruses have different pathogenic mechanisms to avoid host defense. Rhinovirus and adenovirus infection create specific immunity in serum. The human body may be infected for the second time with these viruses because each virus has a lot of different serotypes. Similarly, influenza is also capable of altering its surface antigens and thus creating many different serotypes. The interaction between coro-navirus and host immune activity is unknown, but there may be different strains of coronavirus that can cause short-term immunity. In contrast, parainfluenza virus and RSV have few serotype. Reinfection of these viruses occurs because immunity to them is usually not created after infection. Although viral re-infection is not prevented by host response to the virus, the disease is usually not severe due to a prior immunity.

Expression when infected with influenza virus

Clinical symptoms of the flu usually appear 1-3 days after infection. The first symptom is sore or sore throat, followed by nasal congestion and runny nose. Symptoms of sore throat usually go away very quickly, symptoms of nasal congestion and runny nose are worse on the 2nd and 3rd day. Cough occurs 30% in flu cases and usually occurs after symptoms appear nose. Fever and other flu symptoms usually occur when influenza, RSV and adenovirus infections occur when rhinovirus or coronavirus is infected. Usually, the flu lasts for 1 week, only about 10% of cases last up to 2 weeks.

Clinical manifestations of flu are usually limited to the upper respiratory tract. The secretion of nasal discharge is often recognizable. The color and density of nasal fluid often changes during the course of disease progression, and is not meant to diagnose sinusitis or infection. Nasal sinus examination can detect edema and congestion symptoms, but these symptoms are not specific for diagnosis.

Cure symptoms when you have the flu

Fever: fever symptoms that occur in colds often do not cause complications and the use of antipyretics is generally not indicated.

Nasal congestion: Drugs that cause adrenaline secretion and topical use can reduce nasal congestion. Topical adrenaline-producing drugs that are effective such as xylometazoline, oxymetazoline or phenylephedrine are marketed as drops and sprays. These drugs are also produced with a formulated ingredient that has a slightly reduced (less effective) effect for children, but has not been approved for children under 2 years of age. Oral imidazoline (such as oxymetazoline and xylometazoline) is usually less likely to cause side effects such as rapid pulse, hypotension and coma. Do not use topical adrenalin-inducing medications for a long time because it can cause drug-induced rhinitis (rhinitis medicamentosa) that causes nasal congestion when taking medication continuously. Oral adrenaline-inducing drugs are weaker than sprays and have complications such as central nervous system stimulation, hypertension and palpitations.

Nasal flow: 1st generation antihistamines work to reduce nasal symptoms 25-30%. The effect of relieving nasal discharge is probably related to resistance to cholinolysis rather than antihistamine of these drugs, so the second generation antihistamines (antihistamines do not cause drowsiness) are not works for symptoms of flu. The main side effect of antihistamines is drowsiness, however, there is evidence that this side effect is milder in children than in adults. Runny nose can also be treated with ipratroium bromide, a drug resistant to cholin spray. This drug is similar to antihistamine but does not cause drowsiness. Common side effects of ipratropium are nasal irritation and nasal bleeding.

Sore throat: sore throat symptoms in the flu are usually not severe, indicated for the use of symptomatic analgesics, especially when the patient has muscle pain and headache. Taking acetaminophen in rhinovirus infection has side effects that inhibit the antibody neutralization response, but this is not clinically significant. Aspirin should not be used in children with upper respiratory tract infection because of the risk of Reye's syndrome for children.

Cough: Cough treatment is generally not necessary for children with flu. Symptoms of cough in some children with flu may be caused by the upper respiratory tract from the nasal fluid. Symptoms of coughing in these patients are outstanding at the time of the most nasal symptoms and treatment with 1st generation antihistamines provides good results. Some patients may have a cough for several days to a week from the onset of the disease and may need to use bronchodilators. Studies using codeine and dextromethrophan hydrobromide have been found to be ineffective for cough symptoms of the flu. Drugs like guaifenesin are not effective against cough.

Flu prevention

In general, preventive measures and preventive immunity have not been used routinely for flu. Immunomodulation or immunization against influenza virus can be effective against the flu caused by influenza virus. Vitamin C and equina have all been reported to be effective in preventing flu, but detailed studies on this issue have not recorded the preventive effect of these substances.

Flu can be prevented by preventing the spread of the virus through contact. In the hospital, preventing the spread of respiratory viruses is effective by wearing a mask (or head and face mask) that prevents the spread from hand to eye and hand to nose. Preventing the spread of the virus through direct contact can be highly effective by washing hands in people who have been infected with the virus or who are at risk for infection.