And while meningitis is most often caused by bacteria or a virus, did you know that physical injury, illness, and certain medications can also lead to the condition? There are actually five types of meningitis — bacterial, viral, parasitic, fungal, and non-infectious — each classified by the cause of the disease. Symptoms are similar for each type of meningitis, but there are some differences, says Lorene Cathey, RN, MSN, manager of infection prevention at The University of Tennessee Medical Center in Knoxville. The severity and treatment of the disease differs depending on the cause, so identifying which type a person has is important so he can get the right treatment. Here’s what you should know about the different types of meningitis. Bacterial Meningitis Bacterial meningitis is a potentially life-threatening form of the disease that can cause serious complications such as brain damage, hearing loss, and ultimately death if not diagnosed and treated promptly. This form of meningitis usually occurs when bacteria gets into the bloodstream and travels to the brain and spinal cord. Types of bacteria that can cause bacterial meningitis include Haemophilus influenzae (usually type b), Streptococcus pneumoniae, and Neisseria meningitidis. These bacteria can spread from person to person through coughing and sneezing or saliva transfer during kissing or mouth-to-mouth resuscitation. Certain forms of bacterial meningitis can be caused by eating contaminated food, though sometimes the source is never known. Sudden onset of symptoms such as headache, fever, and stiff neck is common with bacterial meningitis. Other symptoms, such as rash, nausea and vomiting, light sensitivity, and confusion may appear, typically within three to seven days of exposure to disease-causing germs. The symptoms of bacterial meningitis often get mistaken for the flu, which can make diagnosis difficult. Bacterial meningitis can be treated with antibiotics, so it’s important to seek treatment as soon as possible. The best way to protect yourself from bacterial meningitis is to get vaccinated. “Some forms of bacterial meningitis can be prevented by vaccination,” Cathey says. “Meningococcal vaccines protect against most types of meningococcal disease, although they do not prevent all cases.” Pneumococcal conjugate and polysaccharide vaccines are recommended for specific age groups and individuals with certain risk factors, she adds. Haemophilus influenza type b, or Hib, vaccination is recommended for all children younger than 5 years old in the U.S., and it is usually given to infants starting at 2 months old. “Individuals fully vaccinated against Hib may also need additional doses, and unimmunized older children, adolescents, and adults with certain medical conditions should receive Hib,” Cathey says. Viral Meningitis Viral meningitis is more common than bacterial meningitis, and usually less severe. Most cases of viral meningitis are caused by enteroviruses, but other common viruses such as measles, mumps, and chicken pox, as well as some viruses spread through mosquitos or other insects, can also lead to the disease. Viral meningitis has the same types of symptoms as bacterial meningitis, including sudden fever, headache, and stiff neck, but it’s different in that it’s aseptic, meaning bacteria will not grow in the cerebrospinal fluid. It often resolves on its own, without specific treatment, although it may be treated with antiviral medication. In some cases, it can be fatal, depending on factors such as the type of virus causing the infection, the patient’s age, and whether he or she has a weakened immune system. This form of meningitis can be spread by fecal contamination, typically when proper hand washing isn’t practiced after changing diapers or using the toilet. The enteroviruses that cause viral meningitis can also spread through eye, nose, and mouth secretions, or blister fluid, Cathey says. To prevent viral meningitis, wash your hands thoroughly and often, avoid direct contact with someone who has the disease, and make sure you have been vaccinated against measles, mumps, rubella, and chicken pox. Parasitic Meningitis A parasite called Naegleria fowleri is the source for primary amebic meningoencephalitis (PAM), a very rare type of parasitic meningitis. This form of the disease causes a brain infection that progresses rapidly — one to 12 days on average, Cathey says — and is usually fatal. In fact, of the 31 confirmed cases of PAM in the U.S. between 2003 and 2012, all were fatal. Standard meningitis symptoms appear one to seven days after infection, potentially followed by confusion, loss of balance, seizures, hallucinations, and lack of attention to your surroundings. Naegleria fowleri has been detected all over the world in warm freshwater sources (such as lakes, rivers, and hot springs), soil, warm water discharged from industrial sources, poorly treated swimming pools, and water heaters. The microscopic organism enters the body through the nose and travels to the brain where it begins to destroy brain tissue. Parasitic meningitis cannot be transferred by person-to-person contact. Fungal Meningitis Another rare form of meningitis, fungal meningitis, occurs when a fungus enters the bloodstream. Anyone can get this form of the disease, but people with a weakened immune system are at an increased risk. Fungal meningitis is most often caused by inhaling fungal spores from contaminated soil or from bird or bat droppings. Treatment consists of long courses of high-dose antifungal drugs, usually administered in the hospital through an IV. The type of fungus and state of the patient’s immune system determine the length of treatment. Non-Infectious Meningitis Like parasitic and fungal meningitis, non-infectious meningitis cannot be caught from another person. It typically occurs as the result of cancer, lupus, a head injury, brain surgery, or from certain medications. Symptoms are typical of meningitis in general — a sudden onset of fever, stiff neck, and headache, and possibly nausea and vomiting, light sensitivity, and an altered mental state.
