In 2016, 5.6 million children under the age of 5 died.

That’s an average of 15,000 deaths per day, an already upsetting stat is made worse considering that more than half of these deaths were caused by conditions that could have been prevented or treated, according to the World Health Organization (WHO).

Two of the leading causes of death in children under 5 are pneumonia and diarrhea. And as it turns out, there are two ways their associated deaths could be dramatically reduced.

1. Vaccines

There are vaccines for many deadly diseases, including measles, polio, pneumonia due to Haemophilius influenzae type B (Hib) and Streptococcus pneumonia, and diarrhea due to rotavirus.

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By 2016, the Hib vaccine was in 191 countries. Hib causes meningitis and pneumonia — both can kill children. The pneumococcal vaccine was available in 134 countries by the end of 2016, according to WHO. Pneumococcal diseases also include pneumonia and meningitis, as well others.

The United Nations Sustainable Development Goals (SDGs) were set out to ensure healthy lives and promote the wellbeing of children. One of the targets of SDG Goal 3 is to end preventable deaths of newborns and children under 5 years old by 2030. The best way to do so is to ensure access to vaccines.

It is estimated that 2-3 million deaths are prevented every year thanks to immunization programs.

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Global vaccination coverage is at 86% and there have been no significant changes during the past year, according to WHO. Another 1.5 million lives could be saved if vaccination coverage increased.

Nov. 12 is World Pneumonia Day. It’s the perfect moment to highlight the importance of vaccines in preventing unnecessary deaths. Take action here.

2. Water and Sanitation

Goal 6 of the SDGs is to ensure access to water and sanitation for all. Just as vaccines can prevent death from diseases, so, too, can clean water and sanitation.

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Every year, millions of children die because of inadequate water supply, sanitation and hygiene.

It is estimated that 801,000 children under the age of 5 die from diarrhea. That translates to about 2,200 children deaths every day, according to the Centers for Disease Control and Prevention (CDCP).

Unsafe water, as well as lack of access to water for hygiene and sanitation cause about 88% of deaths from diarrheal diseases.

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Improved water sources could decrease the number of diarrheal diseases by 21%, improved sanitation could reduce diarrhea morbidity by 37.5% and the ability to wash hands when it’s most important could decrease diarrhea cases by as much as 35%, according to CDCP.

This World Toilet Day on Nov. 19, remind world leaders that the solutions to improving child mortality rates already exist. They just need to be implemented. Take action here.