Meningococcal meningitis

Transcription

1 Etiological Agent: Neisseria meningitis (1) Meningococcal meningitis By Tho Dao Transmission The transmission of Neisseria meningitis is through direct contact from person to person via droplets or throat secretion from the person who is carrying the bacterium. (1) Some examples of this close contact are kissing, coughing, or sneezing. Another common form of transmission is living in areas where you are in close contact with many people (i.e. dormitories). (4) Reservoirs Meningitis only affects humans which make humans the only natural reservoir of Neisseria Meningitis. It commonly found in the human mucosa. (6) Those who are at the most risk are infants and young children. Along with college aged students who live in dormitories. (4) Nearly 10% of adolescents and adults are transient carriers of Neisseria meningitis, most strains of which usually are not pathogenic. (5) General Characteristics Neisseria Meningitis is a gram-negative diplococci bacterium. The bacteria is non-motile and is passed on among people via direct contact. Neisseria meningitis is oxidase positive and contains the enzyme cytochrome c, this makes Neisseria meningitis aerobic since it uses oxygen to produce energy via the electron transport chain. (3) Key tests for Identification Usually when testing for meningitis the presence of cerebrospinal fluid (CSF) indicates that there is a presence of meningitis. (2) These signs usually indicate the presence of abnormal cerebrospinal fluid; an increased opening pressure, a high white blood cell count, decreased glucose concentration (<45mg/dL), and an increased protein concentration (>45 mg/dl). (2) When diagnosing a patient, the first test doctors use to determine meningitis is a spinal tap, a spinal tap is used to measure the pressure of CSF, typically if there is a CSF abnormality then the conditions listed earlier will result in the presence of Neisseria meningitis. (8). CT scans and MRIs act as supplementary information and are typically performed after the spinal tap. (8) For a laboratory setting the tests used to identify the presence of Neisseria Meningitis are a simple gram stain, Acridine orange stain (Acridine orange is a fluorochrome stain and is more sensitive than gram stain and is better at detecting both intra and extracellular CSF), and the Quellung procedure (a capsular reaction that can identify three specific organism S. pneumoniae, N. meningitis, and H. influenzae.) (7) Signs and Symptoms Meningococcal meningitis can affect two groups of two different age ranges. The first is adults and the other is young children/infants. For an adult they should look out for these signs and symptoms. Chronic intense headaches, fever, nausea, vomiting, phophobia (pain to the eyes via light exposure), seizures and stiff neck. (2) For young children and infants signs and

2 symptoms include; projectile vomiting, seizures, irritability, and Waterhouse-Friderichsen syndrome (hemorrhages in skin and mucous membranes). (2) Historical Information The first case of meningococcal meningitis can be dated all the way back to the 16th century, however the first official reported case was identified by a Swiss physician Gaspard Vieusseux in Switzerland in The first time that the bacterium Neisseria meningitis was identified in spinal fluid and linked to meningitis was by Anton Weichselbaum in Austria in (5) The first recorded major outbreak in Meningococcal meningitis was in Nigerian and Ghana in 1905 and continued till (9) In 1906 researchers found new evidence that horses could produce antibodies that would be able to fend off Meningococcal bacteria. This was the first sign of any kind of vaccination that could be used to treat Meningococcal meningitis. The first official successful treatment of meningitis in America came from Simon Flexner via serum therapy. Later on in the 20th century Chester Keefer had the first successful antibiotic therapy against Meningococcal meningitis with the help of penicillin. (9) The first Meningococcal meningitis vaccine was licensed in the United States in (5) Moving forward in 2002 there was evidence that steroids could improve the prognosis and helped improve the outcome of those infected with this disease. (9) In 2000 a committee from the CDC recommended that colleges and universities need to provide information to all incoming students and their parents about Meningococcal meningitis. (9) Virulence Mechanisms The first virulence mechanism is a polysaccharide capsule that resists phagocytosis and covers the outer membrane of Neisseria meningitis and serves as the biggest contributor to virulence. (5) Another virulence mechanism is IgA protease. The IgA protease of Neisseria meningitis enzymes that are extracellular and human specific. (10) The last major virulence mechanism is that Neisseria meningitis has an extremely toxic lipopolysaccharide, which can produce an endotoxin to aid in its virulence. (5) Control/Treatment Meningococcal meningitis is considered a severe medical condition given that it can lead to serious brain damage and fatality if not treated. Nearly 5-10% of patients die from the disease within the first 24 hours of infection (4) Once infected it is recommended that one seek immediate emergency medical attention. The World Health Organization recommends you should go to a hospital. (4) Medical doctors treat Meningococcal meningitis with antibiotics and treatment should start after an initial spinal tap has been performed to indicate the presence of Neisseria meningitis in the CSF. (4) Being a bacterium Neisseria meningitis can be treated with a wide range of antibiotics which include penicillin, ampicillin, and ceftriaxone. In rural Africa where health resources are limited ceftriaxone is the preferred choice of treatment. (4) Prevention/ Vaccine info Despite being a bacterium based disease Meningococcal meningitis can also be prevented. Currently there are three types of vaccines available. The first is a Meningococcal polysaccharide vaccination (MPSV4) or the brand name is known as Menomune. This one was introduced back in 1974 and helps prevent up to four types of meningitis (those 4 make up 70%

3 of the cases in the United States). (11) The next vaccination is a Meningococcal conjugate vaccine (MCV4) which is similar to MPSV4 but it is recommended for patients who are younger than 55 years of age while MPSV4 is recommended for those who are 55 or older (11). The last available vaccine is a serogroup B Meningococcal vaccination whose biggest name brands are Trumenba and Bexsero. This vaccination is recommended for patients who are between the ages of and is meant for high risk patients. (11) The CDC recommends that all children between the age of 10-24, anyone who is traveling to or living in areas where meningitis is common (Africa, Pakistan, or India), and anyone who have compromised or damaged immune system. (1) Introduced in 2010 there has been a new development in a new meningitis vaccination. A new Meningococcal A conjugate vaccine (Men A) was introduced in Burkina Faso, along with Mali and Niger. (4) The Men A vaccination provides substantial benefits over the current MPSV4. It is more sustainable and provides a higher immune response, it reduces the carrying of the bacteria making it less transmissible. Lastly it is cheaper per dose than the other vaccines. It is currently at $0.5 per dose where any of the existing 3 range from $2.50 to $117 per dose. As of June of 2015 nearly 220 million people have been vaccinated in over 26 African countries as a result of this Men A vaccination being more readily available and low cost. (4) Local Cases or Outbreaks Back in November 29, 2017, The University of Massachusetts Amherst declared a meningitis outbreak after two students tested positive for the same etiological agent of Meningococcal meningitis despite never coming into direct contact with each other. The school worked with the CDC and declared an official outbreak. (12) The school in the following days took preventive actions by setting up multiple walk-in clinics across it s campus. The school while trying to look out for everyone is putting a heavy influence on students (graduate and undergraduate) who live in dormitories, and those with listed immune deficiencies. (12) As of December 1, 2017, nearly 1500 students have been vaccinated with the serogroup B vaccination. The school has not yet made any plans postpone any classes or other university activities until further notice. (12) Global Cases or Outbreaks On March 19, 2017, The Nigeria Centre for Disease Control along with the World Health Organization (WHO) declared a Meningococcal disease outbreak in Nigeria. Cases had been reported beginning in December of 2016 but the country did not declare an official outbreak until March 19, (13) During that period of December March 2017 there was a total of 1,407 reported cases, of that 1,407 cases there were 211 deaths. The main age group that was affected was 5 to 14 year olds. The public health response was quite extensive, WHO, UNICEF, Nigeria Centre for Disease Control, Nigeria Field Epidemiology, ehealth Africa, and many others immediately came to the country s aid and helped contain the outbreak. (13) Following the declaration the current measures that are in place to contain the disease are as follow: Training of local health practitioners on how to perform spinal tap procedures, immediate distribution and injection of vaccines across Nigeria s 5 states, and daily coordination meetings between the five states of Nigeria. (13) With the help of WHO, the Nigeria Centre for Disease Control is taking the overall lead in coordinating with the government and public health organizations. (13)

4 In 2014 there was a mass epidemic of Meningococcal meningitis in 19 African countries. (4) There was roughly 12,000 reported cases which resulted in about deaths. Surprisingly this was the lowest mortality rate of Meningitis in the meningitis belt that any public health organization had ever seen, this was part due to the big push of vaccinations in 2010 (4). As stated earlier nearly 220 million people have been treated with the meningitis vaccination as of June 2015 and the number of outbreaks in the meningitis belt of sub-saharan Africa has decreased significantly to what it was back in (4) These countries include: Uganda, Burkina Faso, Ethiopia, Ghana, Cote d Ivoire, Kenya, Nigeria, and many others. While many of these countries are very much still susceptible to the diseases due to lack of infrastructure. Organizations such as UNICEF and WHO have been able to reduce the number of deaths. (4) Works Cited 1. Meningococcal Disease. (2017, March 28). Retrieved December 05, 2017, from 2. Meningococcal Meningitis. (2017, November 29). Retrieved December 05, 2017, from 3. Neisseria Meningitidis. (n.d.). Retrieved December 05, 2017, from BioWeb from University of Wisconsin 4. Meningococcal meningitis. (2015, November). Retrieved December 05, 2017, from 5. Epidemiology and Prevention of Vaccine-Preventable Diseases. (2016, April 28). Retrieved December 04, 2017, from Chapter 14: Meningococcal Dieseases 6. Van Deuren, M., Brandtzaeg, P., & van der Meer, J. W. M. (2000). Retrieved December 04, 2017, Update on Meningococcal Disease with Emphasis on Pathogenesis and Clinical Management. Clinical Microbiology Reviews, 13(1), Gray, L. D., & Fedorko, D. P. (1992). Retrieved December 04, 2017, Laboratory diagnosis of bacterial meningitis. Clinical Microbiology Reviews, 5(2), Vyas, J., MD, PhD. (2016, July 31). Meningitis - meningococcal. Retrieved December 05, 2017, from 9. Mandal, A., MD. (2017, October 31). History of Meningitis. Retrieved December 05, 2017, from

5 10. Mulks, M., Ph. D, & Plaut, A., MD. (1972, November 02). IgA Protease Production as a Characteristic Distinguishing Pathogenic from Harmless Neisseriaceae NEJM. Retrieved December 05, 2017, from Alli, R. A., MD. (2017, August 11). The Meningitis Vaccines: What Parents Should Know. Retrieved December 05, 2017, from Ducharme, J. (2017, November 29). Meningitis Outbreak Just Declared at UMass Amherst. Retrieved December 06, 2017, from TIME Magazine 13. Meningococcal disease Nigeria. (2017, March 24). Retrieved December 06, 2017, from