Meningococcal Meningitis in the U.S.
History: The Neisseria meningitidis bacterium, carried by clinically asymptomatic individuals, is a major cause of bacterial meningitis worldwide. Outbreaks occur in groups of individuals housed in close proximity, e.g. dormitories, etc. and spread rapidly through the respiratory route. Fatality rates of 10-14% are common as are significant neurologic sequellae for those who survive.
Each year in the US, according to the CDC, there are 1,700-3,400 cases of meningococcal meningitis which are now increasingly resistant to most common antibiotics. Vaccines have been developed and deployed in the U.S. for some, but not all strains of the organism. In the U.S. we lack the ability to immunize against Serogroup B which is the organism found in periodic outbreaks in the Pacific Northwest and other areas.
Notably, a vaccine with proven effectiveness against Serogroup B was developed in Cuba by the Finlay Institute in the 1980s. Since then, 55 million doses have been administered in Cuba and other countries and it is registered for use in 15 countries, but not the United States because of the U.S. embargo against Cuba. Early on, Cuban scientists at the Institute offered their vaccine to U.S. health authorities, which were facing outbreaks on a recurring basis, but received no positive response. (Today, even contacts between researchers from the two countries are stymied: under the Bush administration, CDC (Centers for Disease Control) staff are among the federal employees banned from travel to the island.)
VA-MENGOC-BC :: Epidemiological impact in Havana City: Children below 6 years of age
With the embargo constraint and probable political backlash were the vaccine to be imported, families in the outbreak areas are at ever greater risk of contracting a commonly fatal disease for which antibiotics, even if administered early, may not prevent fatalities. Vaccine manufacturers, seeking larger markets, have been reluctant to commit resources to the development, especially when it is available in any other country with an agreement with the Finlay Institute.
Discussions about the Cuban vaccine with researchers at the CDC and NIH reveal opinions that range from scientific interest tempered with skepticism to outright rejection of the notion. Most assert that the large number of serogroup B subtypes make the vaccine less likely to be effective in other regions. However, one brave researcher opined that there was enough evidence in support of the vaccine to develop a clinical trial. Of course, this is simply an opinion, not a program.
Addressing this concern, European and Cuban investigators published (Vaccine Immunology, Jan. 2007) a report evaluating the immunogenicity and safety of a 3-dose regimen of a variation on the current version of the Cuban serogroup B vaccine. Using a variety of antigenic components of the organism to develop the vaccine, the investigators report that not only did immunization produce antibodies against the related strains in the vaccine, but also against strains not included, confirming the potential for clinical cross-protection. In other words, a population-based clinical trial is certainly merited, and might well provide further evidence of protection. If successful, this would be vital to U.S. citizens, especially in susceptible areas.
Since the vaccine became available in Cuba there have been, in Washington State alone, 1274 cases with 100 deaths and unknown numbers of survivors with permanent neurological impairment. It is worth noting that in some countries, after children are vaccinated against other sero-groups, incidence of sero-group B has actually increased, making the need for a vaccine all the more urgent. This danger is compounded if parents are erroneously let to believe that their children, vaccinated against other strains of meningitis, have been protected against all strains.
Last month there was a small outbreak in Fresno, California. Three cases, all serogroup B were rapidly treated. None of the three had been previously immunized with the available vaccine and all recovered.
Robert Fortner, MD., is a retired nephrologist living on Bainbridge Island.