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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Samir Saha is a scientist who studies bacteria. He works in Bangladesh. I visited him in Dhaka, the capital of Bangladesh. Saha was sending me to see a sick child. The situation would show me why vaccines are important.

Saha studies a bacterium called pneumococcus. These bacteria are found everywhere. They can live in people's throats without getting them sick because our immune system usually fights them off. The immune system protects us from diseases by detecting and killing invaders, like bacteria and viruses.

However, sometimes our immune systems fail us. When this happens, pneumococcus can cause life-threatening diseases. The bacteria can cause pneumonia, an infection in the lungs. They can also cause an infection in the brain called meningitis.

Poorer Children Are More Likely To Get Sick

Young children are more likely to get sick from pneumococcus. Young children in poorer countries that are still developing are even more likely to get sick. In the early 2000s, pneumococcal disease killed more than 800,000 children worldwide every year. The majority of those deaths happened in impoverished countries, such as Bangladesh.

In 2015, a vaccine that prevents pneumococcal disease in children, called pneumococcal conjugate vaccine (PCV), reached Bangladesh. Saha and other scientists are tracking its progress. If PCVs are effective around the world, they could save thousands of young lives.

In the United States, the biggest vaccine challenge is convincing some parents that they should vaccinate their children. However, developing countries have different challenges. Often, people need vaccines but cannot afford them. As a result, vaccine-preventable diseases still cause a great deal of suffering.

This is why Saha sent me to see 11-year-old Sanjida Sahajahan.

The Fever Could Have Been Prevented

When Sanjida was three years old, she developed meningitis. The disease can damage the brain and spinal cord. Now, Sanjida has no control over her head or face, and she cannot talk.

Her mother explained that Sanjida's illness started with a fever. A few days later, she had uncontrollable muscle contractions. Her parents brought her to the hospital. By the time doctors saw her, she was losing consciousness.

Every country has a schedule for the vaccines that children should get at certain ages. When Sanjida was a baby, she received every vaccine she was supposed to get according to Bangladesh's plan. But she did not receive the vaccine against pneumococcal infection. At the time, children in the United States received the vaccine. However, Bangladesh, which desperately needed the vaccine, could not afford it.

Vaccines Take Years To Develop

Vaccines are usually made by private companies in the United States and Europe. The goal of these companies is to make money. Developing a new vaccine is time-consuming and expensive, so manufacturers set prices high to make up the cost.

It took decades to develop a PCV. Part of the reason is that there are nearly a hundred types of pneumococcal bacteria. These types are called serotypes. A serotype might make people sick in one part of the world but not in another. For example, serotype 1 causes little disease in the United States. However, it is one of the main sources of pneumococcal illness in Africa and South Asia.

The first PCV was designed to work against the seven serotypes responsible for most of the disease in the United States. It did not fight off serotype 1. It also cost $232, which most developing countries could not pay.

Rich Nations Step In To Help

Many people thought this situation was unfair. As a result, the Global Alliance for Vaccines and Immunization, or Gavi, was started. Gavi channels money from rich nations to reduce the cost of vaccines for developing countries.

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

Since March 2015, doctors in Bangladesh have received deliveries of the vaccines. Saha's team has noticed a drop in the number of pneumococcal disease cases. He hopes that one day, the vaccines will wipe out pneumococcal disease completely.

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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