Even a small flu can be fatal, influenza pneumonia cannot be ignored!

Author: Chen Xuyan, Chief Physician of Beijing Tsinghua Chang Gung Hospital affiliated to Tsinghua University

Reviewer: Fang Baomin, Chief Physician, Beijing Hospital

Every year, there are patients who die from influenza. They may have been working and living normally a few days ago, but after getting the flu, they suddenly died, which is often hard for people to accept.

This is because some influenza may be complicated with pneumonia, and even more serious patients may be complicated with encephalitis, myocarditis and other organ damage. In this case, it may lead to the death of the patient.

1. Who is more likely to develop influenza pneumonia after getting the flu?

Let’s talk about influenza first. Since it is a viral disease, its biggest characteristic is that it is universally susceptible. People from 0 to 100 years old, men and women, young and old, tall or short, fat or thin, are all susceptible to it.

But influenza pneumonia has its high-risk groups, the youngest and the oldest people, such as children under 7 years old, under 5 years old, or even under 2 years old, as well as the elderly, those over 90 years old. They are all high-risk groups.

In addition, patients with underlying diseases, such as heart and lung diseases, liver diseases, kidney diseases, blood system diseases, tumors, etc., are also high-risk groups.

Also, when it comes to influenza, there is a medical indicator for obese people called body mass index, which is weight (kilograms) divided by the square of height (meters). If it is greater than 30, this is a relatively obese person and is relatively prone to influenza pneumonia.

In fact, from clinical experience, people who are particularly thin will have impaired immunity and are more likely to get severe influenza and develop influenza pneumonia.

Another special group is pregnant women, who are also prone to influenza pneumonia during this special stage.

Another high-risk group is immunocompromised patients, such as AIDS patients, and those who need to use immunosuppressants, glucocorticoids, etc. all year round due to autoimmune diseases. These people should also be particularly careful during the flu season. Once symptoms of infection appear, they should go to the hospital as soon as possible to let the doctor determine whether it is a serious illness.

The above-mentioned groups of people are at high risk of influenza pneumonia or severe influenza.

Figure 1 Original copyright image, no permission to reprint

2. What symptoms should alert you to influenza pneumonia?

Compared with the common cold, the fever symptoms of influenza are usually more severe. One is that the temperature is relatively high, 39℃ or 40℃, and the other is that it lasts for a long time.

In addition to body aches, influenza patients may also have digestive tract symptoms such as nausea and diarrhea, and of course coughs and sore throats, but the most important symptoms are high fever and general discomfort. Some patients may also show obvious fatigue.

For influenza pneumonia, the most prominent symptoms may include coughing, usually without sputum, which is a dry cough; there may also be difficulty breathing, the so-called shortness of breath, which is the most prominent manifestation.

For the patients themselves, since almost everyone of us has had a cold, if you feel very uncomfortable and the symptoms this time feel different from before, you feel particularly weak, and your body temperature is relatively high and the fever lasts longer. It used to go away in two or three days, but this time it has been four or five days and you are still having a fever and it won't go away, accompanied by a severe cough, especially shortness of breath and difficulty breathing, you must go to the hospital to see if it is influenza pneumonia.

If it is just a common flu, it can heal itself with rest and symptomatic treatment, but influenza pneumonia, a typical severe flu, can be fatal.

Figure 2 Original copyright image, no permission to reprint

3. How to treat influenza pneumonia?

For common influenza, the most important thing is to take symptomatic treatment. Fever can be treated by physical cooling, or taking some antipyretics, drinking water, resting, and then self-isolation to avoid infecting family, friends or colleagues. Patients with risk factors can use antiviral drugs such as oseltamivir to reduce the viral load as soon as possible.

If it is influenza pneumonia, symptomatic treatment is also required. Simple viral pneumonia does not require antibiotics, but if a secondary bacterial infection occurs, antibiotics must be actively used for treatment, such as the well-known penicillins, cephalosporins, macrolides, and quinolones. These drugs can be used under the guidance of a doctor.

Fortunately, there are specific anti-influenza virus drugs for influenza. However, it is important to emphasize the timing. The best effect of taking the drug within 48 hours can effectively reduce the viral load and shorten the course of the disease.

If it is more than 48 hours, it is a severe flu, such as pneumonia, encephalitis, myocarditis, or the patient's own immune function is low, we also hope that the patient can take it. If it is relatively mild, just fever, without any complications of common flu, do not use antiviral drugs after 48 hours, because the virus titer can be reduced quickly, so there is no need to use drugs. It will only increase the risk of adverse reactions or drug interactions.

In addition to drug treatment, there are other treatments. Patients with severe pneumonia and respiratory failure need oxygen therapy and respiratory support, including high-flow oxygen, non-invasive ventilation with masks and nasal masks, invasive mechanical ventilation with endotracheal intubation, and even extracorporeal membrane oxygenation (ECMO) support. The specific method to be chosen requires professional doctors to make personalized choices based on the patient's specific situation.