You can catch some diseases simply by breathing. These are called airborne diseases.
Airborne disease can spread when an infected person coughs, sneezes, or talks, spewing nasal and throat secretions into the air. Certain viruses or bacteria take flight and hang in the air or land on other people or surfaces.
When you breathe airborne pathogenic organisms in, they take up residence inside you. You can also pick up germs when you touch an infected surface, and then touch your own eyes, nose, or mouth.
Because these diseases travel in the air, they’re hard to control. Keep reading to learn more about the common types of airborne diseases and what you can do to protect yourself from catching them.
Types of airborne diseases
Many diseases are spread through the air, including these:
The common cold
Millions of cases of the common cold occur each year in the United States. Most adults get two or three colds a year. Children tend to get them more frequently. The common cold is the top reason for absences at school and work. There are many viruses that can cause a cold, but it’s usually a rhinovirus.
Most of us have some experience with the flu. It spreads so easily because it’s contagious about a day before you notice the first symptoms. It remains contagious for another five to seven days. If you have a weakened immune system for any reason, you can spread it to others for longer than that.
There are many strains of the flu, and they are constantly changing. That makes it difficult for your body to develop immunities.
Chickenpox is caused by the varicella-zoster virus. If you have chickenpox, you can spread it for a day or two before you get the telltale rash. It takes up to 21 days after exposure for the disease to develop.
Most people get chickenpox only once, and then the virus goes dormant. Should the virus reactivate later in life, you get a painful skin condition called shingles. If you haven’t had chickenpox, you can get the infection from someone with shingles.
Mumps is another very contagious viral disease. You can spread it before symptoms appear and for up to five days after. Mumps used to be quite common in the United States, but rates have declined by 99 percent due to vaccination. As of September 2016, less than 2,000 causes were reported in the United States. Outbreaks tend to occur in densely populated environments.
Measles is a very contagious disease, particularly in crowded conditions. The virus can remain active in the air or on surfaces for up to two hours. You’re able to infect others up to four days before and four days after the measles rash appears. Most people get the measles only once.
Measles is a leading cause of death among children worldwide and was responsible for 134,200 deaths in 2015. It is estimated that the measles vaccine prevented 20.3 million deaths from 2000 to 2015. The disease is less common in the United States, and occurs mostly in people who haven’t been vaccinated. There were 667 cases reported in 2014 and 188 in 2015.
Whooping cough (pertussis)
This respiratory illness causes swelling of the airways that results in a persistent hacking cough. It’s at the height of contagiousness for about two weeks after the coughing starts.
TB, also known as consumption, is an airborne disease, but this bacterial infection doesn’t spread easily. You generally have to be in close contact with an infected person for a long time. You can be infected without becoming ill or infecting others.
About 2.5 billion people worldwide are infected with TB. Most aren’t sick. About 9.6 million people worldwide have active TB.
People with a weakened immune system have the greatest risk of developing the disease. Symptoms can appear within days of exposure. For some, it takes months or years to activate.
When the disease is active, bacterium rapidly multiply and attack the lungs. It can spread through your bloodstream and lymph nodes to other organs, bones, or skin.
Once a major cause of sickness and death in children, diphtheria is now rare in the United States. Due to widespread vaccination, fewer than five cases have been reported in the past decade. Worldwide, there were about 7,321 cases in 2014, but it may be underreported.
The disease injures your respiratory system and can damage your heart, kidneys, and nerves.
Airborne diseases usually result in one or more of the following symptoms:
- inflammation of your nose, throat, sinuses, or lungs
- runny nose
- sore throat
- swollen glands
- body aches
- loss of appetite
Chickenpox causes an itchy rash that usually starts on your chest, face, and back before spreading over the rest of your body. Within a few days, fluid-filled blisters form. The blisters burst and scab over in about a week.
The measles rash can take as long as 7 to 18 days to appear after you’ve been exposed. It generally starts on your face and neck, and then spreads over the course of a few days. It fades within a week. Serious complications of measles include:
- ear infections
- severe respiratory infection
- swelling of the brain, or encephalitis
Whooping cough gets its name from its main symptom, a severe hacking cough, which is usually followed by a forceful intake of air.
Symptoms of TB vary depend on which organs or body systems are affected and may include coughing up sputum or blood.
Diphtheria can cause marked swelling in your neck. This can make it difficult to breathe and swallow.
Complications from airborne diseases are more likely to affect the very young, the very old, and people with a compromised immune system.
Treatment for common airborne diseases
For most airborne diseases, you’ll need plenty of rest and fluids. Further treatment depends on your specific illness.
Some airborne diseases, such as chickenpox, have no targeted treatment. However, medications and other supportive care can help relieve symptoms.
Some, such as the flu, can be treated with antiviral drugs.
Treatment for infants with whooping cough can include antibiotics, and hospitalization is often needed.
There are drugs to treat and cure TB, although some strains of TB are drug resistant. Failure to complete the course of medicine can lead to drug resistance and return of symptoms.
If caught early enough, diphtheria can be successfully treated with antitoxins and antibiotics.
Airborne diseases happen all around the world and affect virtually everyone.
They spread easily in close quarters, such as schools and nursing homes. Large outbreaks tend to occur under crowded conditions and in places where hygiene and sanitation systems are poor.
Incidence is lower in countries where vaccines are widely available and affordable.
Most airborne diseases run their course within a few weeks. Others, like whooping cough, can last for months.
Serious complications and longer recovery time are more likely if you have a weakened immune system or if you don’t have access to good medical care. In some cases, airborne diseases can be fatal.
What you can do to prevent spreading an airborne disease
Although it’s impossible to completely avoid airborne pathogens, there are some things you can do to lower your chances of getting sick:
- Avoid close contact with people who have active symptoms of disease.
- Stay home when you’re sick. Don’t let vulnerable people come in close contact with you.
- If you must be around others, wear a face mask to prevent spreading or breathing in germs.
- Cover your mouth when you cough or sneeze. Use a tissue or your elbow to cut down on the possibility of transmitting germs on your hands.
- Wash your hands thoroughly (at least 20 seconds) and often, especially after sneezing or coughing.
- Avoid touching your face or other people with unwashed hands.
Vaccines can reduce your chances of getting some airborne diseases. Vaccines also lower the risk for others in the community. Airborne diseases that have vaccines include:
- influenza: vaccine updated every year to include strains most likely to spread in the coming season
- measles: usually combined with vaccine for mumps and rubella, and is known as the MMR vaccine
- mumps: MMR vaccine
- TB: not generally recommended in the United States
- whooping cough
In developing countries, mass immunization campaigns are helping to lower the transmission rates of some of these airborne diseases.