How Common is Meningitis?
Posted: Jun 24th, 2024 at 12:00AM
Meningitis, a type of meningococcal disease, is an infection caused by a virus, bacteria, or fungus that can be treated with early, aggressive therapy. However, if not promptly addressed, it can be life-threatening. In this blog, learn more about how common this infection is, what the meningitis symptoms look like, viral meningitis vs bacterial meningitis vs fungal meningitis, risk factors, and more.
How Many People Get Meningitis?
Every year, approximately 3,000 people in the United States are diagnosed with bacterial meningitis (sometimes called acute bacterial meningitis). The majority of them are infants, kids, college students, and elderly people. Most cases of bacterial meningitis are seen in the winter or early springtime.
This number has gone down drastically over the years, thanks to a vaccine that has virtually eliminated Haemophilus influenzae b (Hib), which is the most common cause of bacterial meningitis in kids.
Additionally, in the US, there are roughly 25,000 to 50,000 hospitalizations each year because of viral meningitis, also called aseptic meningitis. Approximately 90% of viral meningitis cases are caused by enteroviruses, including coxsackieviruses and echoviruses. It can also be caused by herpes simplex virus and mumps.
Unlike acute bacterial meningitis, viral meningitis cases most commonly pop up during the summer and fall.
Meningitis in College Students
As we mentioned, certain groups of people are more likely to become infected. Somewhere between 100 to 125 cases of meningococcal disease happen to young adults on college campuses every year, resulting in five to 15 deaths. Why is this so? Students living close together all year round in close, shared spaces are very likely to catch and spread bacteria and viruses through droplets — for instance, through coughing, sneezing, or kissing.
Cases in Children
Of the total yearly cases of bacterial meningitis, about 70% happen in children five years of age and younger. 2019 data says that ultimately, 236,000 people die every year from meningitis, and about 112,000 of these are children five and under.
Alarmingly, almost 90% of the deaths among children and teenagers happen within 24 hours of diagnosis.
Bacterial Meningitis vs Viral Meningitis vs Fungal Meningitis
Meningitis is an infection and inflammation of the fluid and membranes (also called meninges) around the brain and spinal cord. As we've already touched on, there are different types of meningitis. How do they compare? The distinction lies in the cause of the infection — bacterial, viral, or fungal source.
Viral meningitis is more common — meaning viral infections are the most common cause — but bacterial meningitis is more serious in that it more likely leads to brain damage, hearing loss, stroke, paralysis, and seizures. The most common bacteria that cause meningitis are Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria meningitidis.
N. meningitidis, which causes meningococcal meningitis, has the potential to start epidemics.
Fungal meningitis is a rare fungal infection that occurs around the brain and spinal cord. People with weaker immune systems are at increased risk, a fungal infection anywhere in the body can eventually lead to fungal meningitis. There are different kinds of fungal meningitis, including cryptococcal meningitis.
Very rarely, a parasite can lead to parasitic meningitis.
Interestingly, but in very rare cases, a sinus infection can lead to meningitis.
We can also categorize this infection as acute meningitis or chronic meningitis. Chronic meningitis is long-lasting and is often caused by fungi or Mycobacterium tuberculosis, invading the cerebrospinal fluid. On the other hand, acute meningitis happens suddenly and doesn't last as long.
Bacteria and viruses are the cause, but other things can contribute. For instance, certain lifestyle factors can also put you at a higher risk of certain types of meningitis. For example, individuals with alcohol use disorder might be more likely to have meningitis due to an infection of Streptococcus pneumoniae and Listeria monocytogenes.
Conversely, non-alcoholics might be more likely to become infected due to Neisseria meningitidis.
What Are the Risk Factors?
Who is at an increased risk of meningitis? While anyone can get meningococcal disease, the following can increase the likelihood, according to the Centers for Disease Control and Prevention:
- Age: babies (especially premature infants), young children, teens, young adults, and the elderly
- Certain conditions that may be immunocompromising: HIV, functional and anatomic asplenia, and complement deficiency
- Specific drugs: immunosuppressive drugs
- Certain environments and career paths: microbiologists, healthcare workers, college campuses, the military, international travel to certain countries
- Lifestyle habits: excessive drinking
The Side Effects of Meningitis
For the individuals who survive bacterial meningitis, one in five may experience long-lasting side effects. These can include hearing loss, limb weakness, visual impairment, sensitivity to light, seizures, a stiff neck, a severe headache, problems with speech and language, memory problems, and trouble with communication. Sepsis can also occur, sometimes leading to amputation.
How Effective is the Meningococcal Vaccine?
There are three types of meningococcal vaccination in the United States. They're usually given in multiple doses, and research suggests that protection starts to wane after five years, at which point they might not adequately prevent infection.
More specifically, the MenACWY (or MCV4) vaccine is highly effective when it comes to protecting against four strains of meningococcal bacteria. Three of these strains are common in the US, while the fourth is more likely to be found traveling in countries where meningitis is more common.
Science has proven, time and time again, that vaccines are the most effective way to prevent disease. Learn more about getting the meningitis (MCV4) vaccine.
How to Get Tested and Diagnosed
Health care providers have several ways to test for meningitis. A physical exam can help them identify common symptoms. Blood tests are usually involved to check for bacteria or viruses. In some cases (such as in the emergency room), they may recommend a lumbar puncture, where a sample of spinal fluid is taken and then checked for bacteria or viruses. Lastly, a CT scan can check for problems with the brain, like swelling.
Acute bacterial meningitis often means antibiotic treatment, while antiviral medication and corticosteroids are often used to treat viral meningitis.
If you think you might be experiencing any symptoms of meningitis, or if you were in close contact with an infected individual, it's vital to receive immediate medical care, especially if you have a weak immune system or you're otherwise a high-risk individual. Meningitis can strike fast and hard, so this often requires prompt attention in an emergency setting.
e7 Health provides quick, convenient, and affordable vaccination in Las Vegas. Protect yourself against meningitis and other dangerous diseases. Book an appointment today or contact us with any questions.
