Pneumonia kills more children under five than any other infectious disease
Pneumonia is a common illness, occurs in all age groups, and is a leading cause of death in children across the developing world. Pneumonia is an acute respiratory disease in which fluid fills the lungs, hindering oxygen from reaching the bloodstream.
The global disease burden
More than two million children a year die from pneumonia—one in five of the childhood deaths under age five. Even this estimate may be low in that it does not include pneumonia deaths of newborns. Were neonatal deaths included, pneumonia could account for up to three million deaths per year—as many as one third of under-five deaths each year. Only about half of children sick with pneumonia receive appropriate medical care and fewer than 20 percent of children with pneumonia receive the recommended treatment of antibiotics.
The main cause of pneumonia is Streptococcus pneumoniae, or pneumococcus. More than 90 percent of pneumococcal pneumonia deaths in children occur in developing countries. The pneumococcus bacterium also causes sepsis (an overwhelming infection of the bloodstream) and meningitis (an infection of the fluid surrounding the spinal cord and brain), which kill and disable children worldwide. In addition, pneumococcus is among the most common bacterial causes of disease among HIV-infected individuals and the most common cause of middle ear infections (otitis media).
Treatments to reduce pneumococcal disease and deaths are available, but they reach far too few children. Moreover, antibiotic-resistant pneumococcus is becoming more common worldwide, making prevention of the disease, through widespread use of pneumococcal vaccines, even more critical.
In September 2009, the World Health Organization (WHO) published an article in The Lancet that sheds light on the burden of pneumococcal disease, both globally and within specific countries. Read the article. Pneumonia: The Forgotten Killer of Children, another report released by the WHO and UNICEF in September 2006, further underscores the enormous toll of pneumonia worldwide and the need to improve access to treatment and vaccines. Read the report on the UNICEF website.
Other articles from the scientific literature on pneumococcus are available through PATH's Vaccine Resource Library.
Prevention through vaccines
Since the United States began routinely immunizing children against pneumococcal disease with the vaccine Prevnar® in 2000, the country has nearly eliminated childhood pneumococcal disease caused by the strains included in the vaccine, which are the seven most common in the industrialized world. Synflorix™ and Prevnar 13 Valent®, two other pediatric pneumococcal vaccines, include additional serotypes prevalent in the developing world to offer broader protection against 10 and 13 serotypes respectively.
In general, current vaccines, even with added strain coverage, do not protect against all pneumococcal serotypes. They are also complicated and relatively expensive to manufacture. The high cost of these vaccines makes it difficult for poorer countries in most urgent need to be able to afford them without assistance. While the GAVI Alliance has responded by funding the introduction of current pneumococcal vaccines in low-income countries, new vaccines are also needed that are intrinsically more affordable and that can provide either focused protection for children against strains prevalent in the developing world or broad protection across all pneumococcal strains.
Promising new technologies under development include common protein vaccines that could provide universal protection across all of the more than 90 pneumococcus serotypes, whole cell vaccines that can be inexpensive to produce and administer, and new conjugate vaccines that cost less and focus on serotypes prevalent in low-resource countries.