By Barry C. Fox, M.D., University of Wisconsin
Respiratory infections in humans can cause pneumonia, especially in cases of bacterial pneumococcal pneumonia where the lungs become infected and it becomes rather difficult to breathe. But not all cases of pneumonia are life threatening, not all are caused by the same organisms, and not all respiratory infections affect the lungs. Let us take a look at how different respiratory infections can manifest themselves.
The Medical Threshold
You might be wondering what we could do to prevent a serious medical situation in the case of bacterial pneumococcal pneumonia. Well, there is a common-sense element as to when you should abandon home care and seek medical attention. That “breaking point” is obviously different for each of us individually.
The threshold for seeking medical attention should get lower as we age, due to immune-senescence. Also, if you have other medical conditions that can compromise your immune system, such as having lost your spleen, or taking high doses of a steroid immunosuppressant named prednisone, your threshold should be low.
Vaccinations for Streptococcus
The good news here is there are two vaccinations for Streptococcus pneumonia that are available, a conjugate vaccine with 13 pneumococcal capsule sugar types, and another vaccine that is intended to recognize 23 different capsule serotypes of pneumococcus. It is recommended that children receive the conjugate vaccine in the first years of life, and it’s recommended that all adults 65 and older now receive both types of vaccine once after the age 65.
Some individuals with chronic medical conditions, especially of the heart or lungs, need to receive these vaccinations at least once before the age of 65.You should be aware that there are limits to the efficacy of the vaccinations. Not all types are captured with the vaccines, although they are intended to capture about 85 percent of the types causing invasive disease.
Secondly, your body’s individual immune response may result in antibody production for only some of the serotypes in the vaccine, but not all of them. It is still estimated that the standard 23-valent pneumococcal vaccine leads to a risk reduction of illness of about 50 percent. With the addition of the conjugate vaccine recommendations, the risk of acquiring pneumonia should become even lower.
Learn more about how viruses hijack your body cells.
Viral and Walking Pneumonia
While bacterial pneumonia is most common in adults, the most common cause of pneumonia in children under the age of five is actually viral. Many “snotty nose” viruses that children carry can occasionally end up in their lungs. Unless this is influenza virus, it is usually not life threatening, nor does it usually require hospitalization or antibiotics.
From about the age five through the teenage years, the most common cause of pneumonia is Mycoplasma pneumonia, a germ that’s halfway between a virus and bacteria. This condition is usually suspected on clinical grounds in the appropriate age group and usually does not require hospitalization. It’s often referred to as “walking pneumonia.”
Antibiotics and Germs
Antibiotics that are active against protein synthesis at the ribosomes, such as erythromycin and tetracycline derivatives, are typically prescribed for treatment. Remember, since this germ does not have a cell wall, amoxicillin and cell wall antibiotics would not be effective.
Another cause of pneumonia in adults is Chlamydia pneumonia. This germ is very similar to mycoplasma, but is more likely to affect middle-age adults, and the antibiotic treatment is similar to mycoplasma.
This is a transcript from the video series An Introduction to Infectious Diseases. Watch it now Wondrium.
Virus in the Sinus
Now we’re going to shift our attention to other forms of upper respiratory tract infections. There are several sinuses in the front of the face, which also connect with the respiratory passages of the nose and the back of the throat.
A viral infection causes thickening of respiratory and sinus linings, and also a loss of cilia clearance mechanisms. But the illness is usually viral for the first 10 to 14 days, and the treatment is control of the symptoms, and not antibiotics.
Antibiotics for Infections
All too often at the first sign of a runny nose and congestion leading to pressure over the front of the face, a phone call is placed to primary care physician’s offices requesting antibiotics for an infection. To test the hypothesis that antibiotics have virtually no role in the treatment of sinus infections for the first 10 to 14 days, randomized, double-blind placebo-controlled studies were done.
These demonstrated no difference in the shortening of duration of symptomatic complaints with or without antibiotics. The official recommendation of the Infectious Disease Society of America and of the American Academy of Otolaryngology, then, is initially not to treat sinus irritation with antibiotics.
There are, of course, exceptions that might need antibiotics earlier, including symptoms suggesting early bacterial infection, such as fever more than 101 degrees with severe pain, but these symptoms are not the norm.
Learn more about how bacteria can cause disease.
To complete our knowledge base of upper respiratory infections, we need to learn about bronchitis. The bronchi are the airway tubes between the mouth and the lower lungs. They can also be infected by infectious organisms in a manner similar to the ears and the sinuses.
Rhinovirus, or the common cold, is the most common infectious disease condition in the U.S. These viruses have a propensity to attack the mucous membranes of the nose, throat, and especially the bronchi. It’s not unusual to have nasal congestion symptoms a couple of days before complaining that you now have a chest cold, manifested by a clear and usually non-productive cough, which sometimes keeps you awake at night unless you sit in an upright position.
Well, the main point is that bronchitis, except for in patients with chronic lung diseases such as emphysema, is also exclusively a viral illness, and does not require antibiotics. Similar placebo-controlled trials of antibiotics versus no antibiotics were conducted years ago for bronchitis, with results similar to the sinus studies we just discussed.
Symptomatic care of your cough, likely with decongestants and over-the-counter cough suppressants, is the recommended treatment for bronchitis.
Common Questions About Different Respiratory Infections
The standard 23-valent pneumococcal vaccine leads to a risk reduction of illness of about 50 percent. With the addition of the conjugate vaccine recommendations, the risk of acquiring pneumonia should become even lower.
From about the age five through the teenage years, the most common cause of pneumonia is Mycoplasma pneumonia, a germ that’s halfway between a virus and bacteria.
To test the hypothesis that antibiotics have virtually no role in the treatment of sinus infections for the first 10 to 14 days, randomized, double-blind placebo-controlled studies were done. These demonstrated no difference in the shortening of duration of symptomatic complaints with or without antibiotics.
Rhinovirus, or the common cold, is the most common infectious disease condition in the U.S. These viruses have a propensity to attack the mucous membranes of the nose, throat, and especially the bronchi.