- COVID-19, a contagious infectious disease that threatens the health of the global population, is confirmed to spread via airborne transmission.
- Numerous other infectious diseases, such as influenza and chickenpox, are also transmitted to humans via respiratory droplets that people exhale.
- While most of these diseases have been eradicated or are now easily preventable and treatable, some continue to be responsible for hundreds of thousands of deaths each year globally.
As the threat of a pandemic looms across the globe, fears of a rampant international outbreak have everyone's minds focused on one universal concern: coronavirus disease 2019 (a.k.a. COVID-19). While it has indeed been confirmed that COVID-19 can be transmitted between humans via respiratory droplets that people exhale (such when sneezing or coughing), it is by no means the only infectious disease that can be spread through the air. Here is a list of airborne infectious diseases that you should know about:
Influenza, commonly referred to as "the flu", is caused by 4 different types of influenza viruses - 3 of which affect humans - and compromises the health of your respiratory system (your nose, throat, and lungs). Typically, influenza goes away without any medical intervention, but in certain situations, it can progress to cause potentially life-threatening complications, such as viral pneumonia and secondary bacterial pneumonia. It may also exacerbate previous health conditions, like asthma or heart failure.
Common symptoms of influenza include but are not limited to fever, chills, cough, nasal congestion, sore throat, muscle pains, fatigue, and headache. It is important to note that the influenza virus is not responsible for the stomach "flu" that results in diarrhea and vomiting. However, extreme vomiting, along with chest pain, shortness of breath, dizziness, and confusion, may indicate severe influenza cases that require medical treatment.
Feeling a tickle in the back of your throat? A runny nose? If you don't have influenza, chances are you've fallen victim to the common cold. A cold could be caused by numerous different viruses, but the culprits most frequently responsible are a group of viruses called rhinoviruses ("rhin" is derived from the Greek word for nose).
Remember when your mom told you to put on a warm jacket before going outside, or else you'll catch a cold? Well, despite mom being right about most things, it turns out she was wrong about that myth. There is currently no scientific evidence that proves you can catch a cold from cold weather, nor any studies that confirm chicken soup is an effective cold remedy in humans (but we'll gladly accept a bowl of some anyway!)
Nope, chickenpox does not come from chickens. It's actually an infection caused by the varicella-zoster virus, and it's highly contagious to people who have not yet had chickenpox or haven't received the vaccination against the disease. Chickenpox is characterized by a rash of itchy blisters lasting up to 10 days, and may also include fever, loss of appetite, headache, and fatigue.
Most of the time, healthy children recover from chickenpox without serious issues. However, in severe instances, the entire body can be covered in the rash, causing lesions to form in the throat and eyes.
This disease, caused by the mumps virus, is known to result in one or both of the salivary glands to swell and become painful. Symptoms typically present after approximately 2 to 3 weeks after infection, although it's been reported that some people infected with the virus do not show any signs of the disease.
Mumps can be prevented with MMR vaccine, which protects against three diseases: measles, mumps, and rubella. The incidence of mumps in the United States has plummeted since the vaccine's administration was adopted as a practice of routine preventative medicine.
Measles (also called rubeola), is a viral infection that, like mumps, was not long ago relatively common in North America, but is now prevented with the MMR vaccine. About 2 weeks after exposure to the virus, a blotchy skin rash appears on the infected individual, along with fever, dry cough, runny nose, sore throat, conjunctivitis, and Koplik's spots (small discoloured dots on the inside of the mouth).
Despite having similar names and symptoms, rubeola is not the same disease as rubella. Rubella is an infection caused by a completely different virus than measles, and is not considered to be as infectious or severe, according to the Mayo Clinic.
Whooping cough (pertussis)
If you've ever heard someone infected with whooping cough struggle to breathe during a violent coughing attack, you'll understand how this disease got its name. Whooping cough, also called pertussis, is a respiratory tract infection that is highly contagious, caused by a type of bacteria called Bordetella pertussis. Those infected typically suffer from violent bursts of coughing before taking a breath, a noise that closely resembles the sound "whoop."
Children are protected from whooping cough after they are vaccinated during infancy. The whooping cough vaccine is usually administered at the same time as diphtheria and tetanus vaccines. Over time, the whooping cough vaccine becomes less effective, which is why young adults are considered to be susceptible if an outbreak should occur. However, the most at risk for serious, potentially fatal complications are infants who are under a year old, and those who are unvaccinated or have not yet received all of the 5 injections of the vaccine series, according to the Mayo Clinic.
Tuberculosis, historically referred to as "consumption" due to its associated weight loss, is caused by Mycobacterium tuberculosis bacteria, and primarily impacts the health of your lungs. Only people who have an active infection of tuberculosis can spread the disease through the air (especially when they cough or sneeze); those with latent (unsymptomatic) infection are unable to transmit the disease to other humans.
The good news? While tuberculosis is classified as a contagious disease, it's quite difficult to spread. According to the Mayo Clinic, the probability of transmitting the infection to a family member or colleague is much more likely than a stranger. It's also treatable: the majority of individuals with active disease are no longer considered to be contagious after two weeks of treatment with medication.
Cases of smallpox haven't been reported in the United States since 1949, but up until that point, smallpox was classified as a serious and contagious infectious disease caused by the variola virus, characterized by a fever and skin rash. 30% of those who developed the disease died, but even those who survived did not recover completely unscathed. According to the Centers for Disease Control and Prevention, those who overcame the virus often had permanent scars over large parts of their body and often on their faces, at times resulting in blindness.
The smallpox vaccination officially eradicated the disease around the world in 1980, with the last naturally occurring case arising in 1977. Globally, no new cases have been reported since.
Meningitis can be caused by an array of sources, with the most common being viral and bacterial infections. The disease occurs when the meninges (the membrane over the brain and spinal cord) become inflamed, caused by the infection of the surrounding fluid. The symptoms that present in viral and bacterial meningitis may appear to resemble each other in the early stages of the disease, but the latter tends to progress more severely.
Although rare, anthrax is a serious bacterial infection in which symptoms can take over 2 months to appear. If appropriate medical treatment is not received in a timely manner, all types of anthrax could be fatal.
The Centers for Disease Control and Prevention reminds the public that you cannot catch anthrax from a human via airborne transmission the same way an infected person can spread a cold or the flu. It is possible, however, to become infected through the inhalation of spores in the air when coming in contact with contaminated substances, particularly animal products, like wool, hides, and hair.