Flu turn into pneumonia

It’s hard to fight something you can’t easily detect.

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Pneumonia is treatable, but spotting the infection early is a challenge. The disease has multiple symptoms that can lead people to think their illness is nothing more than the common cold or flu.

“It’s a tough disease to diagnose,” says Marie Budev, DO, a pulmonologist and the Medical Director of Cleveland Clinic’s lung transplant program. “Both can have the symptoms of coughing, fever and chest pain.”

Cause for concern: symptoms beyond 3-5 days

These persistent or severe symptoms are red flags to watch for:

• Serious congestion or chest pain.
• Difficulty breathing.
• A fever of 102 or higher.
• Coughing that produces pus.

Dr. Budev urges any person experiencing chest pain or breathing complications to immediately see a doctor. Pneumonia-like symptoms in very young children or in adults older than 65 are a particular cause for concern.

It is critical to get treatment for pneumonia as soon as possible. It can cause permanent lung damage if left untreated for too long. Because it shares symptoms with the common cold and flu, people often rely on home treatment instead of seeking medical attention. But if you don’t see improvement in a few days, don’t just let it go.

“Pneumonia symptoms last longer than the cold and flu,” says Dr. Budev. “Using the home therapy of rest, fluids and over-the-counter medicine is OK, but if you are still experiencing coughing, chest pain and congestion after three to five days, you should go see a doctor.”

Viral vs. bacterial – how they differ

Those with viral pneumonia will often experience mild fatigue, congestion and coughing without mucus. Since the symptoms of viral pneumonia are usually considered mild, minimal treatment is required. It can be more serious, however, for young children, the elderly and people with weakened immune systems.

People with bacterial pneumonia will often have colored mucus, a fever and chest pain. They should seek medical attention to prevent lung damage.

Bacterial pneumonia can sometimes develop after a cold or flu and often is caused by exposure to the streptococcus pneumonia germ.

Prevention is key

According to the Centers for Disease Control (CDC), pneumonia also can be prevented with vaccines in many cases. Several vaccines prevent infection by bacteria or viruses that, in turn, may cause pneumonia, including:

Dr. Budev stressed the importance of flu shots, in particular, as well as hygiene because the flu itself can leave people vulnerable to more serious infections.

“The flu can be prevented,” says Dr. Budev. “Antibiotics can’t fight off viruses, so in some severe cold and flu cases they will be ineffective. People just need to get a flu shot in preparation for the flu season months of January and February; people need to consistently wash their hands to prevent contraction and spreading of the infection.”

More on pneumococcal vaccines

The pneumococcal vaccine is a shot that helps protect against some of the more than 90 types of pneumococcal bacteria, according to the CDC. There are two pneumococcal vaccines for different age and risk groups, including vaccines:

1.) For children — called pneumococcal conjugate vaccine.

2.) For all adults 65 years and older (and also anyone at high risk for disease who is over age 2) — called pneumococcal polysaccharide vaccine.

For more information about vaccines to help prevent pneumonia, it’s important to talk to your doctor.

Don’t Let the Flu Turn into Pneumonia

The flu lands hundreds of thousands of people in the hospital each year and kills tens of thousands. But flu that leads to pneumonia is even deadlier.

Startling statistic: Flu-plus-pneumonia ranks eighth in leading causes of death in the US.


Every year, pneumonia affects more than one million Americans—and about 50,000 die. People most susceptible to pneumonia include the elderly, especially nursing home residents and individuals who have chronic health conditions such as heart or lung disease. The flu-to-pneumonia progression isn’t the only cause of pneumonia, of course, but since the combo is so deadly—and often so preventable—it’s worth special attention.

Here’s what happens: You get the flu, a contagious respiratory illness caused by an influenza virus. You get the typical symptoms—sore throat, cough, body aches, fever, headaches and chills. But the flu also makes your lungs more susceptible to a bacterial infection caused by Streptococcus pneumoniae (S. pneumoniae), the most common cause of pneumonia in adults.

When that happens, air sacs fill with pus and other liquid, making it harder for oxygen to reach the bloodstream and making it difficult to breathe. Death can come from organs that are starved of oxygen—or from a blood infection (sepsis).

Here’s how to protect yourself…


If you don’t get the flu, you won’t be at risk for that combination of flu virus/S. pneumoniae that is so dangerous to susceptible people. Getting a flu shot is the best way to protect yourself. It is recommended for everyone over the age of six months. While not 100% effective, it does offer substantial protection.

Why a flu shot is so important this year: It’s expected to be a worse-than-average flu season. Australia already had its worst flu season on record—and what happens Down Under often happens in North America. A bad flu year means that pneumonia cases could potentially soar. Fortunately, this year’s flu shot is a good match for the kinds of flu viruses coming our way.


Effective vaccines exist against S. pneumoniae, which, as described earlier, causes the vast majority of pneumonia cases in adults. Everyone age 65 and older should be vaccinated—yet only about 50% of healthy adults in this age group are. Some adults need protection before they turn 65—smokers and anyone with a chronic health condition (heart or lung disease, diabetes, asthma, etc.). For the best protection, you’ll need two different vaccines, spaced out over a year or more…

• Start with a onetime-only dose of the pneumococcal conjugate vaccine called PCV13 (Prevnar 13), which protects against 13 types of pneumococcal bacteria.

• One year later, get a dose of pneumococcal polysaccharide vaccine PPSV23 (Pneumovax), which protects against 23 strains of pneumococcal bacteria. Prevnar 13 primes your immune system so that Pneumovax works better than it would if you took it by itself.

• Based on your age and health, your doctor may advise another dose of Pneumovax five years later.


Certain health conditions and medications can affect your susceptibility to pneumonia…

• Steroids and other immunosuppressive drugs can make you more susceptible to pneumonia. These drugs interfere with the immune response, so your body can’t fight off infection as easily.

Low-dose steroids, even taken long-term, may not increase pneumonia risk, but higher doses (such as 20 mg a day) can do so in as little as two weeks. If you need a high-dose steroid to control your condition, be especially vigilant during flu season—get vaccinated, wash your hands frequently, stay away from crowds, and call your doctor at the first sign of illness such as a sore throat.

• Acid-suppressive medications, such as proton pump inhibitors including omeprazole (Prilosec), as well as histamine-2 receptor antagonists including ranitidine (Zantac), inhibit the production of stomach acids. But these acids help keep harmful gut bacteria in check.

Less acid means more potential for harmful bacteria to colonize and eventually enter the lungs. Unless your doctor prescribes these on a long-term basis (a rare occurrence), use them only for short periods of time—no more than four weeks for heartburn/gastroesophageal reflux disease (GERD), for example.

• Pneumonia occurs less often in adults who get routine dental checkups. Routine dental visits can help decrease the overall amount of bacteria in your mouth, including those that can cause pneumonia in susceptible people. Bonus: A healthy mouth reduces heart disease risk, too.


Since the flu shot doesn’t always prevent infection, be on the lookout for symptoms including feeling feverish, chills, body aches, sore throat and fatigue. If you suspect that you have the flu, call your doctor. You may be a candidate for prescription antiviral medication such as oseltamivir (Tamiflu), which can shorten your illness duration and possibly decrease the odds of it progressing to pneumonia. But you need to take it within a day or two of the first symptoms for it to be effective.


Adults hospitalized with pneumonia have a heightened risk for cardiovascular problems including sudden heart attack, often with no warning signs. What happens: Oxygen deprivation from a bout of pneumonia can starve cardiac muscle cells so that they function less well or even die off. One study found that within the first month of pneumonia diagnosis, the risk for stroke, heart attack or death due to heart disease grew by as much as fourfold…and remained elevated for years. Patients recovering from pneumonia also are predisposed to developing it again—another good reason to prevent it in the first place.

What Is The Connection Between Influenza and Pneumonia?

Influenza (flu) is a highly contagious viral infection that is one of the most severe illnesses of the winter season. Influenza is spread easily from person to person, usually when an infected person coughs or sneezes.

Pneumonia is a serious infection or inflammation of the lungs. The air sacs fill with pus and other liquid, blocking oxygen from reaching the bloodstream. If there is too little oxygen in the blood, the body’s cells cannot work properly, which can lead to death.

Influenza is a common cause of pneumonia, especially among younger children, the elderly, pregnant women, or those with certain chronic health conditions or who live in a nursing home. Most cases of flu never lead to pneumonia, but those that do tend to be more severe and deadly. In fact, flu and pneumonia were the eighth leading cause of death in the United States in 2016.

For both influenza and some types of pneumonia there are protective vaccines, although none are 100 percent protective. As flu strains change each year, it is necessary to get a flu vaccination each season to make sure you are protected against the most current strains. Pneumonia vaccinations are usually only necessary once, although a booster vaccination may be recommended for some individuals. Ask your healthcare provider if you are up to date on your vaccinations and to determine if any additional vaccinations are right for you.

  • Learn more about preventing influenza and pneumonia, or find a flu vaccine near you using the Flu Vaccine Finder.

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Some flu seasons hit harder than others. Vaccination and good hygiene are key in preventing the spread of cold and flu, but sometimes there’s nothing you can do to stop illness from setting in. While colds or influenza are often treatable at home with over-the-counter medicine you shouldn’t take these illnesses lightly. These illnesses can lead to serious complications, including pneumonia.

Can a cold or flu become pneumonia?

We often hear that a cold or flu turned into pneumonia. That’s not accurate. However, pneumonia can develop as a secondary bacterial infection after the flu or a cold. Pneumonia, ear infections, and bronchitis can all result from flu or cold.

Bacterial infections are the most common cause of pneumonia in adults. Bacterial pneumonia causes the alveoli of the lungs to become inflamed and fill with fluid. Pneumonia can affect one or both of the lungs.

What are the symptoms of pneumonia?

Symptoms of pneumonia can vary. They may resemble common cold and flu symptoms, including fever, difficulty breathing, chest pain, and coughing up phlegm or mucus.

Symptoms of pneumonia can be mild or severe. It’s easy to mistake pneumonia as a stubborn cold or flu that won’t go away. It’s incredibly important, however, to catch pneumonia early on to prevent serious complications.

Talk to a doctor if you have difficulty breathing, you have a persistent fever, or if you have symptoms that do not get better after a few days.

How can you prevent pneumonia?

Many cases of pneumonia result from complications of a cold or the flu. This means that preventing these illnesses can help prevent pneumonia.

  • Get a flu shot each year to help prevent the spread of flu, and reduce flu symptoms.
  • Wash your hands often, and wash them well. You can’t wash your hands too much during cold and flu season.
  • You can usually treat colds at home, but you should visit the doctor if you suspect that you or someone in your home has the flu. A doctor can provide you with medication that may help shorten the duration of your illness, and prevent complications such as pneumonia.

Visit a MANA clinic today

Even healthy people can get the flu and suffer complications from the flu. Don’t take your chances with pneumonia. Get your flu shot today, and talk your doctor if you suspect that you have the flu, or if you have cold symptoms that last more than a few days.

myMANA makes scheduling appointments easy, and MediServe Walk-In clinics are are open from 7:00 a.m. to 7:00 p.m. 7 days a week for your convenience.

Our pediatric walk-in clinic is open Monday – Friday 8 am to 7:30 pm and Saturday 8 am to 11 am.

Several Family Medicine clinics and Fayetteville Diagnostic Clinic offer walk-in hours as well or you can request a same day appointment.

The illness can be mild, which is known as walking pneumonia, or it can be serious if the symptoms are severe, and may require hospitalization, Dziura said. Bacterial pneumonia is the most common form of the illness and also tends to be the most serious type.

With pneumonia, the alveoli, or air sacs, in one or both lungs become inflamed and fill with fluid. This makes it difficult for oxygen to reach the bloodstream. (When both lungs are infected, it’s called double pneumonia.)

More than 250,000 people have to seek care in a hospital for pneumonia each year in the United States, and about 50,000 Americans die annually from it, according to the Centers for Disease Control and Prevention (CDC).

What causes pneumonia?

Pneumonia can be caused by bacteria, viruses and fungi. However, bacteria are the most common cause of pneumonia in adults, and the most frequent culprit is Streptococcus pneumoniae. Walking pneumonia is usually caused by a bacterium called Mycoplasma pneumoniae.

Viruses, such as influenza (flu) virus and rhinovirus, can also lead to pneumonia. Other viral causes include respiratory syncytial virus (RSV), which is a common cause of pneumonia in babies and young children, and human metapneumovirus, according to the National Heart, Lung, and Blood Institute.

One example of a fungal cause of pneumonia is Pneumocystis jirovecii, which causes a serious life-threatening infection typically found in people with weak immune systems, such as those with HIV and AIDS. (This illness was previously called Pneumocystis carinii pneumonia.)

Pneumonia can happen any time of year, but more cases tend to occur in winter when the flu season takes off, Dziura said. Flu can cause viral pneumonia and can weaken immune defenses, which increases the risk of developing a secondary bacterial pneumonia, she explained.

People of all ages can get pneumonia, but those most at risk for the lung infection are children under age 5, adults 65 and over, cigarette smokers and people with other health problems or weak immune systems, such as chronic lung problems, heart failure, diabetes and stroke.

Viral and bacterial forms of pneumonia can typically spread when an infected person coughs or sneezes, which releases droplets containing bacteria or viruses into the air that other people can breathe in or touch on contaminated surfaces. Most people who spend only a short amount of time with an infected person will not become ill, but there are some bacterial types of pneumonia that can spread quickly in people who live or work in crowded settings, such as college dorms, military barracks or nursing homes.

Symptoms of pneumonia

The symptoms of pneumonia can range from mild to life-threatening. A person with walking pneumonia may feel weak and fatigued, and have a low-level cough, but is still able to attend work or school, Dziura said. A more serious infection causes a dangerously high fever, shortness of breath, blueness of the lips due to a lack of oxygen in the blood and mental confusion.

With some forms of pneumonia, a person may cough up greenish or yellow mucus, or possibly bloody mucus (but pneumonia doesn’t always cause you cough up mucus). According to the American Lung Association, symptoms of pneumonia may include:

  • Cough
  • Fever
  • Chest or stomach pain
  • Shortness of breath
  • Chills
  • Loss of appetite
  • Lack of energy and fatigue
  • Confusion, especially in older people
  • Headache

A doctor may listen to a patient’s lungs for a crackling sound that when the patient breathes, which would indicate an infection. (Image credit: )

Diagnosis and treatment

Pneumonia is a very common illness but can sometimes be tricky to diagnose because the symptoms are often similar to having a cold. To diagnose pneumonia, a doctor will use a stethoscope to listen for a crackling sound in the lungs when the patient breathes in, Dziura said. A chest X-ray can show the extent of inflammation in the lungs.

Patients may also be asked for a sputum (a mixture of saliva and mucus) sample that gets examined to identify the strain of bacteria causing pneumonia, which helps doctors to tailor antibiotic treatment, Dziura said.

In at least 50% of cases, the specific bacteria causing pneumonia can’t be identified, Dziura said. So, the antibiotic given is based on the most common bacterial causes of pneumonia.

People with bacterial pneumonia usually start feeling better within 48 hours after receiving antibiotics, but a course of antibiotics is typically taken for five to 10 days, Dziura said. However, the cough caused by pneumonia can linger for up to three months after treatment has ended because of residual inflammation in the lungs that takes longer to subside, she said.

Antibiotics won’t help treat viral pneumonia. Its symptoms, such as fever and cough, are managed with rest, aspirin, cough medicine and drinking plenty of liquids. Experts also recommend running a humidifier to keep the air moist, which helps loosen excess phlegm in the lungs and sinuses.

For some older adults and people with chronic lung problems or weak immune systems, pneumonia can quickly become life-threatening. People may experience serious complications as a result of the infection, such as trouble breathing in enough oxygen; a build-up of fluid around the lungs; or sepsis, a condition where there is uncontrolled inflammation in the body, which may lead to widespread organ failure.

Ways to avoid getting pneumonia

One of the keys to preventing the spread of pneumonia is to avoid close contact with people known to be infected with colds and flu, Dziura said. Other ways to prevent the illness include:

  • Getting vaccinated: A yearly flu shot can help prevent influenza and is also good protection against pneumonia. There is also a vaccine to prevent pneumococcal pneumonia, the most common form of bacterial pneumonia. This vaccine is recommended for children under age 2 as well as for adults 65 or older. The shot is also advised for children and adults at increased risk for pneumonia because they have other health conditions or weakened immune systems.
  • Keeping hands and surfaces clean: Wash hands frequently— after using the bathroom, blowing your nose, changing a diaper, preparing foods or before eating. Disinfect surfaces touched often, such as faucets, doorknobs, phones, toys and light switches.
  • Quitting smoking. Cigarette smokers are at increased risk for pneumonia because tobacco damages the lungs’ ability to fight infections. That’s why smokers are advised to get the pneumococcal vaccine.
  • Maintaining a strong immune system. Eating a healthy diet, plus regular exercise and sufficient sleep, can all protect against getting sick.

Additional resources:

  • Here’s how the American Lung Association explains walking pneumonia.
  • Learn more about the two kinds of pneumococcal vaccines from the CDC.
  • Read why people can still get pneumonia in the summer, from the American Lung Association.

3 Ways to Tell the Difference Between the Flu and Pneumonia

A cough is also a major symptom of pneumonia, but it has a different nature. A pneumonia cough tends to be productive, bringing up dark-colored phlegm that may contain blood, says Dr. Lovell. Pneumonia is characterized mainly by respiratory symptoms, says Joshua Scott, MD, primary care sports medicine physician at Cedars-Sinai Kerlan-Jobe Institute in Los Angeles—that includes shortness of breath or difficulty breathing.

If it’s the flu, symptoms are usually far more severe, says Dr. Scott.

How quickly did your symptoms show up?

It’s very common for flu symptoms—fever, muscle aches, stuffy nose, sore throat, etc.—to arrive so suddenly that it’s possible to pinpoint the exact moment all your misery began, says Kimberly Brown, MD, MPH, an emergency medicine doctor in Memphis.

Pneumonia, in contrast, typically has a less dramatic entry, with symptoms ramping up over several days, says Dr. Lovell.

RELATED: Bronchitis vs. Pneumonia: How to Tell the Difference

What does your doctor say?

Seeing tons of patients gives doctors a knack for knowing which disease is which. “Sometimes patients come in and they just look like the flu,” says Dr. Brown—the air of misery, along with the runny nose, is a giveaway even before she asks about symptoms.

Doctors also use diagnostic tools. Listening to the lungs or taking a chest X-ray can reveal signs of pneumonia.

“There is a nasal swab test that can determine if you have the actual flu virus,” says Dr. Scott.

When it comes to viruses—either viral pneumonia or the flu—there’s not much doctors can do to help, with one big exception. If you have the flu, and get to the doctor right after you notice your symptoms, your doctor may prescribe an antiviral medication—like Tamiflu—to lessen the course and severity of symptoms, says Dr. Scott.

The catch? Antivirals are only effective if you use them ASAP—within one to two days of the onset of symptoms. And taking Tamiflu isn’t necessarily a pleasant experience; side effects can include nausea, vomiting, diarrhea, and dizziness. “The side effects may be worse than your actual flu symptoms!” says Dr. Brown.

Even if you miss the window for antivirals, it’s still worth it to get a diagnosis, says Dr. Scott. A doctor’s visit is an opportunity to rule out complications of the flu or the possibility you have another disease (like pneumonia), he says. And, if you have vulnerable members in your home—like an elderly person, for instance—they might want to take Tamiflu as a preventive measure, he says.

And what about if you think you have pneumonia? That’s trickier. You’ll need to visit the doctor if you have bacterial pneumonia to get a prescription for antibiotics. That’s not necessary for viral pneumonia, which you mostly have to wait out while treating the symptoms.

Dr. Brown’s advice: “If you are concerned about any of your symptoms, you should see a physician right away.”

If it turns out you have either viral pneumonia or the flu (and didn’t take Tamiflu), doctors typically recommend supportive care: Rest up, drink lots of fluids, and manage your symptoms with over-the-counter medications. Consider this further evidence that your grandma’s advice to have some chicken soup when you’re feeling under the weather is sound policy.

RELATED: 13 Home Remedies for Bronchitis That Might Finally Ease Your Cough

Common sense—and vaccinations—are the best prevention tactics

The flu is one of the viruses that can cause pneumonia, says Dr. Lovell. Here’s why: All of those secretions from your stuffy nose, combined with the dehydration that often accompanies the flu, create an environment where bacteria can multiply too fast for your body to defeat, potentially leading to bacterial pneumonia, explains Dr. Scott.

If you didn’t get a flu shot yet, head to the doctor’s office or pharmacy stat. “Vaccinations for both the flu and pneumonia save lives and decrease hospitalizations,” says Dr. Lovell.

For healthy people, a flu shot reduces your chances of getting the flu, says Dr. Scott. And while it’s still possible to get the flu even after a vaccination, the shot will lessen both symptoms and how long the flu lingers, Dr. Scott says. Vaccines can also help prevent the most common cause of bacterial pneumonia, says Dr. Lovell. (These are usually recommended for young children, older adults, and people with certain underlying health conditions.)

Along with getting vaccinated, consider having a hands-off policy during this germ-heavy season, avoiding hugs and handshakes, says Dr. Scott, and wash your hands frequently (and especially after handshakes). This will help you avoid getting sick. Wipe down potentially germ-covered surfaces at home and work, says Dr. Brown. And, adds Dr. Lovell: Drink lots of water and maintain good nutrition.

RELATED: Why Do Some People Die From Pneumonia?

The bottom line

Wash your hands and get vaccinated for the flu (and check with your doctor about pneumonia vaccinations) to ward off these two diseases.

And if you are generally in good health and under 65, don’t get overly stressed if those preventive measures don’t work and you do contract the flu or pneumonia. Both diseases can be very serious, says Dr. Brown, but, she adds, “the vast majority of healthy people do well with treating the flu or pneumonia outside of the hospital.”

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