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What Is Double Pneumonia? Pope Francis's Diagnosis Explained.

Pope Francis is being treated in hospital for bilateral pneumonia, otherwise known as double pneumonia, according to a statement released by the Holy See Press Office on Tuesday (Feb.18). Vatican News shared details of the announcement the same day.

The statement noted that Pope Francis, 88, was hospitalized on Friday (Feb. 14) after experiencing bronchitis symptoms for several days. Tuesday's statement described the pope's condition as still being "a complex picture."

It added that he has a "polymicrobial infection," meaning an infection driven by multiple germs. The infection arose in the context of one chronic and one acute lung condition, respectively called bronchiectasis and asthmatic bronchitis. The statement added that the pope remained "in good spirits" and was spending his time alternating "between rest, prayer and reading."

On Saturday, Francis experienced an asthma-like respiratory crisis of "prolonged intensity," Vatican News wrote in a statement. His blood tests revealed a low platelet count, which required blood transfusions, and on Sunday the Holy See Press Office revealed that he was also showing early signs of mild kidney failure. However, they added that it is "currently under control."

As of Monday (Feb. 24), while his condition remains critical, the pope is reportedly "alert and well-oriented."

What is double pneumonia?

Pneumonia is typically caused by bacteria, viruses or fungi infecting the lungs and the body reacting to that infection. This causes inflammation, swelling and fluid accumulation in the small sacs of the lungs, called alveoli.

There are many different microorganisms that can cause the condition, including those responsible for the common cold, the flu and COVID-19. (Pneumonia can also sometimes arise when food or drinks are inhaled into the lungs, causing "aspiration pneumonia.") Bacterial pneumonia is more common and usually more severe than viral pneumonia, which is more likely to cause mild symptoms that resolve on their own, according to nonprofit medical center Cleveland Clinic.

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Related: How do people die of the flu?

Common symptoms of pneumonia include chest pain, difficulty breathing, fever, chills, nausea, vomiting and persistent cough. If the condition becomes severe, it can lead to life-threatening complications, including heart damage, death of lung tissue, respiratory failure, or acute respiratory distress, which prevents the lungs from properly filling with air.

Notably, the pope has a polymicrobial infection, which means it is caused by multiple different microorganisms, and as such may require more complex treatment.

Double, or bilateral, pneumonia means that the infection has affected both of the pope's lungs. He is now being treated with antibiotics, which fight bacterial infections, and corticosteroids, which help suppress inflammation, according to Tuesday's statement.

Severe pneumonia is also often treated with oxygen therapy or a ventilator, but the statement did not note if the pope has received such breathing support.

Who is at risk of pneumonia?

Anyone can develop pneumonia, but some groups of people face a higher risk of the condition.

Those who are most at risk include older adults and young children; those with a chronic lung or heart condition; those with a neurological condition that affects swallowing; hospital patients or individuals living in care facilities; smokers; pregnant people; and those with weakened immune systems.

According to the National Center for Health Statistics, part of the U.S. Centers for Disease Control and Prevention (CDC), more than 41,000 people died from pneumonia in the U.S. In 2023 and 1.4 million emergency department visits were primarily due to pneumonia in 2021.

Most people with pneumonia are treated with antibiotics and will recover after two to four weeks, according to the U.K. National Health Service (NHS) website, but adults over 65 are more likely to require hospital treatment and experience more severe illness.

What is bronchitis, asthmatic bronchitis and bronchiectasis?

Pope Francis was particularly at risk of developing pneumonia because he already had several conditions affecting his lungs, such as bronchiectasis.

Bronchiectasis is a long-term condition where the bronchi — the major airways of the lungs that branch off the windpipe — widen, leading to more mucus than usual to build up in these airways. This can put the lungs at greater risk of subsequent infections. Bronchiectasis can be caused by damage to the tissue and muscles surrounding the bronchi, which might have happened due to a previous lung infection, for example.

Symptoms of bronchiectasis vary widely from person to person, but usually include shortness of breath and a persistent cough that brings up phlegm, according to the NHS website.

The Holy See statement also noted the pope had asthmatic bronchitis. This is a condition in which an individual has both asthma and acute bronchitis, causing symptoms such as chest tightness, wheezing, difficulty breathing and fever.

Bronchitis, broadly, is a disorder where the bronchi become inflamed. It is more common in people with asthma because asthma constricts these airways and also makes them hypersensitive to irritants. This can lead to bacteria or viruses getting trapped and causing damage.

Pope Francis may also be particularly prone to lung problems because, as a younger man, he developed a condition called pleurisy and had part of one of his lungs removed, age 21. Pleurisy is a condition characterized by inflammation of the lining of the lungs and chest cavity, which can cause sharp chest pains, especially when breathing in, coughing, sneezing or moving. The condition can be caused by autoimmune diseases or cancer, as well as emerge after trauma to the chest or blood clots in the lungs. Usually, though, it is caused by infections. Sometimes, pleurisy is a sign of pneumonia. It may also cause damage to the lungs that increases the risk of other respiratory illnesses, such as bronchitis.

Editor's note: This article was updated on Monday (Feb. 24) after new reports on the development of Pope Francis' conditions were released.

Pope Francis Is Ill With Double Pneumonia. What Does That Mean?

ROME, ITALY - FEBRUARY 20: A candle with the Pope Francis image, flowers and candles left by the ... [+] faithfuls are seen below the sculpture of St. John Paul II at the main entry of the Policlinico A. Gemelli Hospital where Pope Francis is being treated for a double pneumonia on February 20, 2025 in Rome, Italy. According to a press release issued by the Holy See Press Office on Thursday evening, Pope Francis clinical condition is showing slight improvement, he has no fever and his hemodynamic parameters remain stable. Pope Francis was hospitalized in Rome on Friday with bronchitis, and was subsequently treated for a respiratory tract infection. (Photo by Franco Origlia/Getty Images)

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The pope is seriously ill with double pneumonia. What does that mean?

"Double pneumonia," also called bilateral pneumonia, means both lungs are infected. When things are worse, you might hear "multi-lobar," meaning multiple parts of your lungs are infected.

In pneumonia, the lung sacs where air is exchanged, called alveoli, become inflamed and filled with pus and fluid. This can cause your blood oxygen to go down and might cause you to need breathing support of oxygen or, in severe cases, mechanical support on a ventilator.

Symptoms most often include cough, sputum production, shortness of breath and fever. Pleurisy, or pain when you breathe, is common. Older people might be too weak to have much of a cough or fever, or just have a new and unexplained confusion or become less alert.

The pope has underlying lung diseases that increase his risk of pneumonia. He had part of a lung removed for infection in 1957 and a previous hospitalization for pneumonia in 2023. Pope Francis has asthmatic bronchitis — recurrent bronchitis triggered by allergies.

The pope also has bronchiectasis, which is the widening of the bronchi, or tubes that carry air to your lungs. This leads to pooling of mucous and increased infections from the bacteria and secretions not being cleared normally. Many things, including chronic obstructive pulmonary disease, autoimmune illnesses, immunodeficiency and cystic fibrosis, can cause bronchiectasis.

Treatment For Pneumonia

Specifics about the pope's antibiotic therapy aren't publicly available. Typically, the choice of antibiotics is guided by culturing a sputum sample and testing it against a variety of antibiotics to see which will kill the bugs that have grown in the culture. Some hospitals have newer technologies like the BioFire FilmArray pneumonia panel, a bacterial polymerase chain reaction assay, which can detect some viruses and atypical organisms like Mycoplasma. Ideally, you want to use the most specific antibiotic possible to limit toxicities and the emergence of more resistant bacteria.

A report about the pope's progress said, "the drug therapy was strengthened after the multiple infections were diagnosed." He's also been receiving oxygen through a simple nasal cannula. Unfortunately, he needed steroids to reduce the lung inflammation or help with asthma. Steroids raise blood sugar and can necessitate insulin for diabetes. It also contributes to the growth of more difficult-to-treat organisms like fungi.

What To Expect For The Pope's Recovery

The pope was admitted to Rome's Gemelli hospital on Feb. 14. He was said to have a "complex respiratory infection, involving bacteria, virus and other organisms." The good news is that he did not have a bloodstream infection or sepsis, which has a mortality rate as high as 50%.

The pope's physicians indicated that he was "a not-terribly-compliant patient in the past" and was a workaholic. There are concerns, too, because the pope is overweight and sedentary, which can cause weakness and complications. His difficulty raising secretions and clearing his lungs is a particular concern

If all goes well, Pope Francis is expected to stay in the hospital for another week.

Prognosis Of Pneumonia

Pneumonia is serious at any age, but particularly for young children or the elderly, who have weaker immune systems. Other than childbirth, it's the most common cause of hospital admissions in the U.S., with a million hospitalizations and 50,000 deaths.

Pneumonia is the eighth leading cause of death and is the leading infectious cause of death in the United States. Hospital-acquired pneumonia has a higher death rate than that acquired in the community. Compared to CAP, HAP's mortality rate was 11.1% vs. 5.1% in one study.

While the pope is improving, he has a long way to go. Broad-spectrum antibiotics have numerous side effects, including liver inflammation, bone marrow suppression and debilitating (and sometimes deadly) diarrhea from Clostridium difficile.

Ways To Reduce Your Risk Of Pneumonia

There are a few things you can readily do to stay healthier. First, stay current on immunizations, including COVID-19, influenza and pneumococcal pneumonia vaccines. The flu shot reduces the risk of subsequent pneumonia by 25% to 53%. Pneumococcal or staph pneumonia commonly follow influenza. Effective vaccines against pneumococcal pneumonia are available. Please get them!

Influenza and COVID-19 are both airborne viruses, so masking can markedly reduce your risk of infection, particularly if you wear an N95, KF94s (S. Korean), or KN95s (from China). Look for a reputable dealer and learn how to spot fake masks that are not protective.

If you do become ill, particularly if you are elderly, or if you notice a family member with worsening shortness of breath, fever or low body temperature, or confusion, please seek medical care immediately.

Pope Francis Has Bilateral Pneumonia

Pope Francis, who remains hospitalized, has bilateral pneumonia, the Vatican said on Tuesday.

The term simply means pneumonia in both lungs, said Dr. James Musser, director of the center for infectious diseases at the Houston Methodist Research Institute. He added that, without examining a patient, he could not say anything specific about his condition.

In general, pneumonia is an infection of the small airways of the lungs. As the body mounts an inflammatory response, small pockets in the lungs fill with immune cells; symptoms can include fever, cough and shaking chills. To diagnose the illness, a doctor typically asks the patient to say a long "e," as if the person were singing. Through a stethoscope, the "e" of a pneumonia patient sounds like an "a," said Dr. Paul Pottinger, a professor of infectious diseases at the University of Washington.

Most people with pneumonia recover well at home and do not need to be hospitalized. But for older people, pneumonia can be "a deadly situation," infectious disease experts said.

Dr. Peter Chin-Hong, professor of medicine and infectious diseases at the University of California, San Francisco, added that "the mortality rate goes up after age 85." The pope is 88, and is missing part of one lung after pulmonary surgery in 1957.

The most likely cause of pneumonia is an infection caused by a bacterium, Streptococcus pneumoniae, according to Dr. Chin-Hong. "The No. 1, 2 and 3 cause of pneumonia is strep pneumonia," he said.

The illness can respond to antibiotics, but bacteria can sometimes spill out of the lungs and into the rest of the body, resulting in sepsis, a dangerous situation. A vaccine can help mitigate this sepsis risk but does not prevent the condition, Dr. Chin-Hong said.

Dr. Pottinger noted that, although strep pneumonia can involve both lungs, it usually is confined to one lobe of one lung. Most bilateral pneumonia, he said, is caused by viruses, including influenza, or other bacteria. Other causes include respiratory syncytial virus, or R.S.V., Legionella, mycoplasma and chlamydia, Dr. Pottinger said.

He agreed with Dr. Chin-Hong about the likely gravity of the pope's condition.

"It is a very scary situation," Dr. Pottinger said.

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