Weak immune system, chronic disease, polluted environment… are the reasons why flu symptoms last longer.
Doctor Bach Thi Chinh – Medical Director, VNVC Vaccination System – stated the above idea, right when the Binh Dinh Center for Disease Control reported 9 people positive for influenza A/H1N1pdm, of which 4 died, on November 22.
According to Dr. Chinh, common symptoms of influenza A are sore throat, headache, muscle and body aches, dry cough, runny nose, weakness, fever over 38 degrees Celsius with chills…, usually recovered within 2-7 days. However, the flu virus can multiply and massively attack the lungs, respiratory system… if the following factors are encountered.
Immune system decline
According to Dr. Chinh, when the immune system is weakened, the body is unable to create antibodies, making it difficult to fight against outside pathogens or infections caused by viruses and bacteria.
Meanwhile, the A/H1N1 influenza virus spreads quickly and strongly. People with immunodeficiency (pregnant, diabetic, chronic obstructive pulmonary disease, cancer, organ transplant, taking anti-rejection drugs, abusing corticosteroid steroids…), when infected with influenza A/ H1N1, symptoms and virus transmission time will last longer, making complications more likely.
Typically, 4 people who died from influenza A/H1N1 in Binh Dinh were all over 50 years old and had a series of chronic diseases such as hypertension, chronic obstructive pulmonary disease, diabetes, and Cushing’s syndrome.
In cases where pregnant women are anemic, obese, or have asthma, the risk of flu infection is nearly twice as high as that of healthy pregnant women. If infected with influenza A/H1N1, they are 7 times more likely to be hospitalized and three times more likely to die than non-pregnant people of reproductive age.
A 2019 study published in the American Library of Medicine showed that people with weakened immune systems when infected with influenza A/H1N1 are more likely to have it prolonged because they cannot eliminate the virus themselves. Besides, patients are easily infected with viruses, bacteria, fungi… making the disease worse.
“Influenza virus, when entering the body, will attack and damage the respiratory mucosa, exposing hidden adhesion sites, creating conditions for bacteria or fungi to penetrate and cause superinfection, thereby weaken the ability to clear secretions from the respiratory tract,” explained Dr. Chinh.
Typically, influenza creates conditions for pneumococcal bacteria to colonize the oropharynx, leading to superinfected pneumonia. They also disrupt the production of white blood cells, reducing their effectiveness in fighting infections.
Flu usually recovers in 2-7 days but can linger. Image: Vecteezy
Controlling underlying diseases during flu is even more difficult, causing the disease to persist. For example, people with chronic obstructive pulmonary disease (COPD) are often older, have weaker immune systems, and are more susceptible to flu and have an increased risk of flu-related exacerbations.
“In addition, the nature of the airways is narrowed and constricted. If infected with influenza, the inflammation will be severe and prolonged. In severe stages, the patient may have difficulty breathing, become pale, lethargic, even respiratory failure…”, said Dr. Chinh.
Children
Children’s immune systems are not fully developed, they have the habit of sucking their hands and objects…, making them susceptible to threats from bacteria and viruses.
When influenza A/H1N1 attacks the nose, throat and lungs, it will create nasopharyngeal secretions, while children do not know how to eliminate them, so they swallow them. This habit causes the flu virus to multiply, the illness lasts longer, and there is a high risk of sore throat and respiratory infections…
Furthermore, when sick, children are often picky eaters and rarely drink milk, leading to weaker resistance, further promoting the proliferation of flu viruses.
Elderly people get flu vaccine at VNVC. Image: Dieu Thuan
Polluted environment
According to Dr. Chinh, factors like smoke, fine dust, waste, chemicals… are also factors that cause flu symptoms to last longer. Research on the American Library of Medicine shows that in the period 2013-2019, influenza and environmental pollution were related to 248,151 cases.
UNICEF identifies that poor air quality causes short-term health consequences such as: difficulty breathing, respiratory infections, susceptibility to asthma and long-term health effects (stroke, cardiovascular disease, lung cancer, heart disease, etc.). chronic obstruction).
Vietnam is in the high pollution group. According to a report from the Ministry of Natural Resources and Environment, this year’s air pollution level increased by an average of 10% compared to 2023. The amount of PM2.5 fine dust and other toxic particles increased significantly.
UNICEF cited a recent study of 15,000 children in Ho Chi Minh City, showing that most have a link between respiratory symptoms and poor air quality due to smoking and cooking.
Self-treatment
Many people think that flu is a common illness. When they have symptoms of cough, sore throat, runny nose, fever…, they choose to treat with folk remedies; arbitrarily buy or take the same medicine as prescribed or listen to someone’s “tip”.
Doctor Chinh emphasized that overuse of corticosteroids when suffering from flu can easily cause a decline in resistance and bacterial superinfection, while also causing the flu virus to multiply and massively attack important organs. Therefore, the disease not only lasts a long time, but also leaves many consequences.
Most recently, a 37-year-old woman who contracted the flu (due to overuse of corticosteroids to treat the flu) suffered from superinfected pneumonia and multiple organ failure and had to run ECMO for 37 days at Bach Mai Hospital (Hanoi).
According to research in groups with underlying medical conditions, antiviral drugs are most effective within 48 hours of symptom onset. Later, it is likely to increase the rate of hospitalization, prolonged treatment and intensive resuscitation.
Doctor Chinh pointed out that influenza A/H1N1 is genetically recombined from influenza viruses in pigs, birds and humans. This structure creates conditions for the virus to adapt and spread from person to person, causing a flu pandemic in 2009. Each year our country records 600,000 to one million cases of seasonal flu, of which about 10% of cases are positive for the flu strain. A/H1N1.
Worldwide, WHO reports that each year there are about one billion cases of seasonal flu, of which 3-5 million are severe cases, and 290,000-650,000 deaths.
WHO and the Ministry of Health recommend vaccination as a way to prevent influenza and its complications. Currently, Vietnam has a quadrivalent influenza vaccine to prevent 4 common virus strains: A/H1N1, A/H3N2, B/Yamagata, B/Victoria, for 6-month-old children and adults.
Children from 6 months to 9 years old, who have never had a flu shot before: get two basic shots one month apart and then repeat every year. People aged 9 years and older only need one injection, after that, a booster dose is needed every year.
“It is necessary to get a flu vaccine booster every year to promptly update new flu vaccines, prevent infection with circulating strains and antigenic changes. The vaccine is up to 90% effective in preventing disease,” said Dr. Chinh.
According to the Department of Preventive Medicine (Ministry of Health), in the last months of the year, our country’s temperature often drops low, cold air and storms easily weaken the immune system, creating conditions for influenza viruses to attack. In addition to vaccination, people should proactively dress warmly, wear masks when going to crowded places, keep the place clean and eat enough nutrients to increase resistance.