Meningitis is an inflammation of the protective membranes, known as the meninges, that surround the brain and spinal cord. The answer to whether a person can contract this condition more than once is yes, it is possible. Recurrence is primarily attributed to the broad range of causes that can trigger the inflammation, meaning a single infection does not grant immunity to all types. Although recurrent episodes are rare, they can occur months or even years after the initial illness.
The Different Forms of Meningitis
Meningitis is classified based on the cause of the inflammation, with the main categories being viral, bacterial, and fungal. Viral meningitis is the most common form and is typically the least severe, often resolving on its own within a week or two with supportive care. Viruses like non-polio enteroviruses are the most frequent cause of this type.
Bacterial meningitis, in contrast, is less common but represents a serious medical emergency due to its potential to be life-threatening. Common bacterial culprits include Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae type b (Hib). Untreated bacterial meningitis carries a mortality rate of approximately 10 to 15%.
Fungal and parasitic meningitis are less frequent, often only affecting individuals with compromised immune systems. Non-infectious causes also exist, such as certain medications or autoimmune conditions. An infection from one specific pathogen does not create immunity against the numerous other viruses, bacteria, or fungi that can cause the condition, thus allowing for multiple distinct episodes.
Factors That Predispose Individuals to Repeated Infection
Recurrence of the same type of meningitis, particularly the bacterial form, is rare but suggests an underlying vulnerability in the host. One major predisposing factor is an anatomical defect that provides a direct pathway for pathogens to enter the central nervous system. These defects can be congenital, such as malformations in the inner ear, or acquired, such as a skull fracture or prior head trauma that results in a cerebrospinal fluid (CSF) leak.
CSF leakage creates a communication between the sinuses, nasal passages, or ear and the subarachnoid space, allowing bacteria from the nasal cavity to pass through a breach in the skull base. Anatomical issues are the primary cause for about 59% of recurrent cases, and the most common bacterial cause of recurrent episodes is Streptococcus pneumoniae.
Vulnerabilities in the immune system also increase the risk of repeated or relapsing infections. For instance, individuals who have undergone a splenectomy or who have functional asplenia, such as those with sickle cell anemia, are less able to filter and clear encapsulated bacteria. Genetic conditions that affect the complement system, a part of the immune response, also impair the body’s ability to destroy certain bacteria like Neisseria meningitidis, leading to a higher risk of recurrence.
Reducing the Risk of Future Infections
The most effective strategy for preventing future episodes, particularly the most severe forms, is through vaccination. Vaccines protect against the three main bacteria responsible for the majority of severe cases: Neisseria meningitidis, Streptococcus pneumoniae, and Haemophilus influenzae type b (Hib). Routine immunization schedules include the pneumococcal conjugate vaccine, the Hib vaccine, and the meningococcal vaccines (MenACWY and MenB), which protect against specific serogroups.
Vaccinations help the immune system recognize and destroy these pathogens before they can cause infection. For individuals with identified anatomical defects, surgical correction of the CSF leak or congenital anomaly is the definitive method to prevent further recurrence. Close contacts of a person with certain types of bacterial meningitis may also be given prophylactic antibiotics to prevent the spread of the infection.
General hygiene practices are important for limiting the spread of the numerous viruses that cause the milder form of the disease. This includes frequent hand washing, avoiding close contact with sick individuals, and refraining from sharing personal items like drinks or utensils. While vaccines do not protect against every possible cause, they significantly reduce the risk of contracting the most dangerous, highly contagious forms of meningitis.