Meningococcal disease, or meningitis, is a bacterial infection of the meninges, or lining around the brain and spinal cord. If left untreated, it has a 50% mortality rate, and it spreads most easily through crowded areas where people are in close and prolonged contact, from college dorms to informal settlements. Meningococcal disease can result in severe, permanent conditions such as brain damage, hearing loss, and learning disability (WHO). Furthermore, children and youth are more at risk from the disease. This means that meningococcal disease has lasting repercussions on cycles of poverty in the developing world. Effective vaccines are available, but uptake is nowhere near universal. The highest incidences of meningococcal disease occur in the 21 countries of the “Meningitis Belt,” a region that extends from Senegal to Ethiopia. Immunization and surveillance efforts have mostly focused on this region, where there have been over 800,000 reported cases in the last 15 years. Meningococcal disease occurs to varying degrees all over the world, however, and less attention is paid to prevention and surveillance outside of the Meningitis Belt, which can lead to high human and economic costs, especially in low- and middle-income countries.
A few weeks ago, the Sabin Vaccine Institute, in collaboration with the Pan American Health Organization (PAHO), Johns Hopkins’ International Vaccine Access Center (IVAC), and the CDC, announced the preliminary findings from a study on meningococcal meningitis in the Latin American-Caribbean region (LAC). The study examines the prevalence of the disease and the cost of prevention and of controlling outbreaks in the LAC region. The Executive Vice President of the Sabin Vaccine Institute, Ciro de Quadros, M.D., M.P.H., revealed the findings at the Regional Meningococcal Symposium in Buenos Aires at the end of last month. The symposium was convened by the Sabin Vaccine Institute and PAHO. Last week, Dr. de Quadros answered my questions about meningococcal meningitis and the implications of the Sabin study.
Q: Although incidence rates vary around the world, meningococcal meningitis can be found almost anywhere, from the U.S. and Europe to South America, Asia, and sub-Saharan Africa. Why does this disease receive so little attention from the public, governments, and even the medical/scientific community?
Dr. de Quadros: In the past, meningococcal disease did not receive as much public attention as other infectious diseases (such as HIV/AIDS or malaria) due to the sporadic nature of the disease. However, the disease does attract considerable attention from both the media and the public in countries where meningococcal outbreaks occur more regularly with seasonal variation. Meningococcal disease outbreaks produce tremendous concern in the public community, and pressure for a rapid public health response usually follows media reports of an outbreak.
However, there is a lack of coverage and attention paid to the need for constant surveillance and preventive vaccination programs. It is not a coincidence that in our new study the countries with the highest incidence rates also had robust surveillance programs. This leads us to believe that several countries in Latin America and elsewhere suffer not just from major outbreaks, but also regular occurrences of the disease—it is just not monitored or reported by government health systems.
Q: Much of the attention that does exist focuses mainly on the so-called “Meningitis Belt” of sub-Saharan Africa, where incidence rates are highest and epidemics more common. What has been the effect of this on efforts in other places, namely the Latin America-Caribbean (LAC) region? Why is it important to focus on the LAC region now?
Dr. de Quadros: Since much of the attention surrounding meningococcal disease has focused on the African “meningitis belt” there has been a gap in the understanding of the disease in other parts of the world with significant incidence rates, including the LAC region.
Remarkable progress has been made in efforts to control meningococcal meningitis epidemics in sub-Saharan Africa. Most notably, a mass immunization campaign against serogroup A meningococcus was implemented in 2010.
Now it is important to focus on meningococcal disease in other parts of the world, specifically the LAC region, since highly effective meningococcal vaccines are available to prevent this potentially fatal disease. The advantages of mass vaccination include a high level of protection and greater long-term efficacy against meningococcal infections.
Q: Your study finds that reported disease burdens fluctuate widely between countries in the LAC region–where countries with strong surveillance and reporting have higher incidence rates of meningococcal meningitis and those with weak or non-existent surveillance programs have few cases. Furthermore, in this day and age, travel makes it easier to carry diseases across borders. What is your sense of the incidence rates in the LAC region? How can those governments without a strong health infrastructure to track and prevent this disease improve their surveillance and prevention measures?
Dr. de Quadros: As of know we only are touching the tip of the iceberg as far as this disease is concerned and the real magnitude of the problem is not entirely known. Most LAC countries need to develop their surveillance infrastructure for meningococcal disease. This infrastructure should include both clinical case detection as well as laboratory capacity to diagnose and characterize Neisseria meningitidis. The sharing of surveillance data between local and national health authorities should be strengthened as well. As countries realize the importance of this disease, it will be necessary to build upon the surveillance systems that were organized to fight polio, measles, rubella, rotavirus and pneumococcal disease and introduce up to date diagnostic methodologies in order that the real burden of the disease can be ascertained.
Q: What are the implications of your study’s findings and the next steps to combat meningococcal meningitis in the LAC region?
Dr. de Quadros: The Meningococcal Disease Study’s findings, the cost analysis together with the burden of disease data, are essential to planning and implementing strategies to prevent and reduce the morbidity and mortality rates due to meningococcal disease.
Vaccination strategies to control meningococcal disease in the LAC region can only be developed with sufficient understanding of the changing epidemiology and costs of the disease. For this reason, Sabin intends to distribute a final report of the study’s findings to national policymakers and public health officials in Latin America and the Caribbean.
Q: In the context of the global recession, which has ushered in funding cuts and smaller budgets among donors and government health programs, what can be done to curb meningococcal meningitis?
Dr. de Quadros: When we release the full study it will be clear that the cost of an outbreak far exceeds the cost of a health program that includes a meningococcal vaccine. In addition to rapid response and hospitalization costs associated with an outbreak, up to 20 percent of meningococcal disease survivors develop permanent disabilities including deafness, neurological deficit or limb amputation—only adding to the long-term economic impact of an outbreak.
Despite initial costs, I feel the most effective methods to curb meningococcal meningitis are comprehensive surveillance and reporting programs that will help governments better track and ultimately manage outbreaks as well as preventative vaccines.
Header photo: teens in Burkina Faso show off their vaccines for meningitis A. By Gates Foundation, via Flickr, CC BY-NC-ND 2.0.
