Here’s Why Vaccines Are so Crucial

Here’s Why Vaccines Are so Crucial

If children in poor countries got the shots that rich countries take for granted, hundreds of thousands of young lives could be saved.


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Biology, Health

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It was morning in Dhaka, the capital of Bangladesh. I was with scientist Samir Saha. He sent me to see a girl whose life had been changed by a preventable disease. The situation would show me the importance of vaccines.

Saha is a microbiologist, internationally recognized for his research on a bacterium called pneumococcus. Pneumococcal bacteria are found everywhere. They are easily spreadable and can live in the nasal passages of healthy people without causing harm.

However, when our immune systems fail us, pneumococcus can migrate, multiply and set off life-threatening diseases. It can cause pneumonia, which is an infection in the lungs. Pneumonia leads to rapid breathing, fever, a rattling cough and blue lips. The bacteria also can cause meningitis, which is an infection in the tissue lining the brain, as well as infections in the bloodstream.

Young children are especially vulnerable to pneumococcal bacteria. Children in places without easy access to antibiotics and good medical care are the most vulnerable of all. At the start of the 21st century, pneumococcal disease was killing more than 800,000 children worldwide every year. The majority of those deaths occurred in impoverished countries such as Bangladesh.

Vaccination Efforts Are Important

In 2015, a vaccine that prevents pneumococcal disease in children, called pneumococcal conjugate vaccine (PCV), reached Bangladesh. Saha's research team is tracking its progress. If PCVs are effective around the world, it could save thousands of young lives.

Coming from a country like the United States, it can be easy to imagine that the biggest vaccine challenge is convincing parents that they should vaccinate their children. Those efforts are important but even more urgent is the international effort to get new vaccines to children in developing countries. In these countries, vaccine-preventable diseases still cause a great deal of suffering.

This is why Saha sent me to 11-year-old Sanjida Sahajahan. I hopped into a van to get to her family's home.

Sanjida Missed Out On One Badly Needed Vaccine

When I arrived, Sanjida was propped up in a small plastic armchair. When she was three years old, she developed meningitis, which can cause irreversible damage to the membranes that surround the brain and spinal cord. She has no control over her head, face or the sounds she makes. She is unable to form words.

Her mother explained that the illness started as a fever. A few days later, Sanjida was having uncontrollable muscle contractions. Her parents brought her to the hospital, but by the time doctors saw her, she was losing consciousness.

When she was a baby, Sanjida had received every vaccine in Bangladesh's national immunization plan at the time. This included whooping cough, measles, tetanus, hepatitis B and polio. But she did not receive the vaccine against pneumococcal infection. At the time, children in the United States received the vaccine, but countries like Bangladesh, which desperately needed the vaccine, could not afford it.

No one can accurately tally the total number of lives saved by vaccines, but it remains one of the greatest achievements of modern medicine. Measles, for example, killed more than two million children a year worldwide in the 1980s. By 2015, vaccination had dropped the death toll to 134,200. Mass vaccination has also ended polio in all but three countries. Bangladesh was pronounced polio-free in March 2014.

Developing New Vaccines Is Expensive

Delivering vaccines in Bangladesh is not easy, but the Bangladeshi inoculation program has remarkable reach. Vaccines must be kept at just the right cold temperature to preserve their potency. Maintaining this "cold chain" is difficult in countries like Bangladesh, which have hot climates and shaky power grids. Yet, Bangladesh has worked hard to preserve the chain. Bangladesh has also worked hard to spread public service ads about inoculation, and the general public remains open-minded about vaccines.

The real problem is that people often cannot pay what vaccine manufacturers charge, even though they desperately need the vaccine. Vaccines are usually made by private companies in the United States and Europe that aim to make money. Developing a new vaccine is time-consuming and expensive, so manufacturers set vaccine prices high to make up for the cost.

It took decades to develop PCVs, partly because there are nearly 100 versions, or serotypes, of pneumococcal cells. A serotype might make people sick in one part of the world but not in another. Serotype 1, for example, causes little disease in the United States but is one of the main sources of pneumococcal illness in Africa and South Asia.

Bangladesh Is Receiving New Deliveries

The first PCV was one of the most expensive in history. It was designed to work against the seven serotypes responsible for most of the disease in the United States, but it did not fight off serotype 1. It also cost $232 per four-dose course, which most people in developing countries could not pay.

The situation was unfair, according to Orin Levine. He is the vaccine delivery director at the Bill and Melinda Gates Foundation.

Others who shared Levine's opinion started the Global Alliance for Vaccines and Immunization, or Gavi. The alliance channels money and resources from wealthy nations, such as the United States, the United Kingdom and Norway, into vaccine support for poorer countries. It helps to reduce the cost of vaccines for developing countries.

Gavi devotes a half-billion dollars a year to PCV support, and the alliance has also made special arrangements with PCV manufacturers. As a result, the manufacturers have developed new versions of the vaccine that work against serotype 1.

Since March 2015, Bangladeshi health officials have regularly received deliveries of the vaccines. Health officials say that the vaccines are reaching families all over the country. Saha's team has noticed a drop in the number of pneumococcal disease cases. He hopes that one day, the vaccines will wipe out the pneumococcal disease completely and his research will no longer be needed.

Media Credits

The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit. The Rights Holder for media is the person or group credited.

Cynthia Gorney
Tyson Brown, National Geographic Society
Production Managers
Gina Borgia, National Geographic Society
Jeanna Sullivan, National Geographic Society
Program Specialists
Sarah Appleton, National Geographic Society, National Geographic Society
Margot Willis, National Geographic Society
Last Updated

March 8, 2024

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