Children in South Asia and Africa continue to face the threat of infection from meningitis. Despite progress in vaccines, there are still poor health infrastructures in key areas and inadequate access to medical services.
The World Health Organization (WHO) says promoting vaccination programs faces challenges, with outbreaks of several forms of meningitis causing child mortality rates as high as 60 percent across Sub-Saharan Africa.
Meningitis still threatens children
Mathuram Santosham, a professor of pediatrics and pediatric medicine at John Hopkins Bloomberg School of Medicine, said while vaccinations programs have been very successful in the West and developed regions, children in developing countries remain at risk.
"The disease pretty much disappeared in the U.S., Europe and other countries. It's now working well; but the places where children are dying are not Western countries and European countries, it's India and Africa," he said.
"When a child gets meningitis, even when the best care is available the mortality is between three and 10 percent. But in the poor countries where there isn't good access to medical care, it can be as high as 60 percent," Santosham told VOA.
The disease largely affects young children.
Meningitis has lasting effects
Even for those who survive, there is a 30 to 40 percent chance of serious neurological complications affecting the child's long term health.
The major cause of bacterial meningitis - one of several forms of the disease - is the Haemophilus Influenza type b or Hib.
The disease causes an acute inflammation of the protective membranes covering the brain and spinal cord, known together as the meninges.
Vaccines have been very effective since 2000
In 2000, the WHO estimated Hib was responsible for 8.13 million cases of serious illness worldwide, leading to some 371,000 deaths a year. Reports say the annual death toll has now fallen to less than 200,000.
A 2015 paper in The Lancet magazine noted the success of the new vaccines, such as Hib, in reducing mortality rates and globally an almost two-thirds decline in global meningitis deaths by 2030.
Developing a vaccine for meningitis has been a long term challenge.
A professor at the U.S. National Academy of Sciences, Porter W. Anderson, began work on a Hib vaccine in 1968 with a vaccine effective for older children, but not in those under the age of two.
Help for children under age 2
A breakthrough in the research for younger children came in the collaborative work between U.S. scientists John B. Robbins and Rachel Schneerson, who succeeded in developing a vaccine for children under two years of age.
Robbins told VOA the breakthrough was significant. "The ability to prevent an infection that not only killed infants and children but maimed them after they were treated was wonderful. It kept on pushing us," he said.
Up to the end of 2016, the WHO says the Hib vaccine has been introduced in 191 countries. Vaccine coverage varies from 90 percent in the Americas but falls to around 28 percent in the Western Pacific Region.
In Africa, the WHO recommends large scale vaccinations of "population groups that are at risk" amid the constant threat of outbreaks especially in Sub Saharan regions.
Schneerson said it is crucial the vaccine reaches globally.
"It's for everybody and most of those infectious diseases are more prevalent in poor countries. We live in one world. We live in a boat which is becoming smaller and smaller. We all live together. We have to take care of each other," Schneerson said.
In the U.S., the success of the vaccination program has led to a dramatic decline in cases.
Prior to the launch of the immunization program in the mid-1980's, Hib-meningitis infected 20,000 U.S. children a year with five percent of those dying and one-third left with intellectual disabilities. Since then the the annual death toll has been less than 100.
Opposition to vaccines
But Santosham said there was resistance to the vaccination program's implementation.
"There's also a tremendous amount of anti-vaccine lobbies in countries like India and even the United States and in many parts of Europe also. They were putting out false information saying this vaccine is dangerous," he said.
In India, a strong anti-vaccine lobby stalled a national vaccination program, leading medical authorities to directly appeal to the individual states and local politicians about the need for the program.
But Santosham said China and Thailand had not yet signed up for the program, but he expected China's private medical sector to play a key role, while Thai health care workers are looking for government funding "in the next year or two".
Projections of the success of the vaccinations led experts to predict more than seven million lives would have been saved due to the program by 2020. "So this is a tremendous success story," Santosham said.
The four scientists, Rachel Schneerson, John B. Robbins, Porter W. Anderson and Mathuram Santosham, recently visited Thailand as recipients of the Prince Mahidol medical awards in Public Health.