Vaccines and Gavi, the Vaccine Alliance: A Global Health Issue Q&A

What are vaccines? 

Vaccines are one of the most powerful public health tools in human history. A type of medicine, vaccines are usually injected into the body to stimulate the immune response against a specific infectious disease.

When a new vaccine is developed, it goes through extensive testing and research before it is released to the public. Tens of thousands of study participants, scientists, and medical experts participate in the research process to ensure a vaccine’s safety and benefits. It can take years to develop a vaccine. The accelerated release of a vaccine during an emergency is sometimes made possible due to decades of prior research and global collaboration. For example, scientists had already published extensive research on the coronavirus before the COVID-19 pandemic, allowing for the vaccine’s release in 2021. 

In high-income countries like the United States, vaccines have transformed daily life by decreasing, and in some cases eliminating, diseases that once injured or killed millions. In the 20th century, measles infected millions of Americans each year before a vaccine became available in 1963; this vaccine paved the way for the U.S. to declare measles eliminated in 2000. Similarly, polio infected about 16,000 Americans each year before a vaccine became available in 1955. The disease was considered eliminated in the U.S. in 1979. And diphtheria, once the leading cause of death for children in the U.S., has not had a single case reported for two decades.

It takes about three weeks for immunity to develop after vaccination, but that protection can last a lifetime. Many vaccines are given in infancy and childhood to protect children early in life, before exposure to severe disease increases and while their immune systems are still developing. In some cases, mild side effects from vaccines occur, such as low fever, tiredness, and soreness at the injection site, but vaccines are carefully designed, tested, and distributed to have the greatest impact for human health.

What is in a vaccine?

Every ingredient in a vaccine serves a specific purpose, and each component undergoes rigorous safety testing. The primary ingredient is related to the virus or bacterium the vaccine is designed to protect against. Vaccines work by safely introducing part — or a weakened form — of a pathogen into the body. This stimulates the immune system to produce antibodies.

There are three main approaches to vaccine design:

• The whole microbe approach uses the entire virus or bacterium in a weakened or inactivated version of the virus.

• The subunit approach uses only specific parts (proteins or sugars) of a virus or bacterium to trigger immunity.

• The genetic approach uses genetic instructions (such as mRNA) that teach cells to produce a harmless piece of the pathogen, prompting an immune response. 

Other vaccine ingredients

In addition to the active component, vaccines may contain:

• Stabilizers (such as sugar or gelatin) to protect the vaccine during storage and transport

• Surfactants to prevent ingredients from separating or clumping

• Diluents, such as sterile water

• Adjuvants (such as aluminum salts) to strengthen the immune response

• Preservatives to prevent contamination in multidose vials

One ingredient, thimerosal, is a preservative that allows for vaccine shelf life and cuts the need for refrigeration. Since the 1930s, thimerosal has been used to prevent bacterial and fungal contamination, including in multidose vaccines. It contains a form of mercury that the body clears quickly.

When the U.S. adopted a single-use policy for vaccines in the late 1990s, misinformation and disinformation spread about thimerosal, causing some to question its safety. The ingredient was largely phased out of vaccines within the U.S. at this time. However, extensive research has found the amount of mercury contained in thimerosal insignificant and safe. It is now used only in multidose vials in high-risk areas around the world.

Who has access to vaccines?

Access to vaccines today has made it possible to live largely free from the devastation that shaped so much of human history. However, this protection from disease is not universal. Around the world in low-income and high-risk countries, preventable childhood diseases continue to claim lives and devastate families. Where access to vaccines is limited, outbreaks of measles, whooping cough, and other infections remain a serious threat.

Recognizing this global gap, Gavi, the Vaccine Alliance, was established in 2000 with a clear mission: to make vaccines accessible and affordable for children in the world’s poorest countries. The U.S. was one of Gavi’s founding and largest donors. Over the past 25 years, Gavi estimates that it has helped vaccinate hundreds of millions of children and has prevented an estimated 18.8 million deaths. Through partnerships with governments, manufacturers, and global health organizations, Gavi negotiates lower vaccine prices and strengthens immunization systems in high-risk regions.

“Efforts in disease prevention and control, such as vaccination campaigns and treatment programs, have dramatically reduced the spread of deadly illnesses like malaria, tuberculosis, and HIV/AIDS.” — “The Importance of Improving Global Health”

What is the relationship between the U.S. and Gavi today?

The U.S. has long played a significant role in supporting global immunization through Gavi. However, recent political developments have introduced tension into that relationship.

For fiscal year 2026, Congress approved $300 million in foreign aid funding for Gavi, although the U.S. executive branch withdrew from formal Gavi board representation and canceled a five-year funding agreement. In January 2026, U.S. Secretary of Health and Human Services Robert F. Kennedy Jr. released a pre-recorded video acknowledging Gavi’s global health work but accusing the organization of not taking vaccine safety seriously. He referenced a 2017 study concerning the DTPw vaccine and announced the withdrawal of U.S. funding unless Gavi discontinued its use.

The DTPw vaccine protects against diphtheria, tetanus, and pertussis (whooping cough) and uses the whole microbe approach. It is widely used in high-risk settings because it provides strong, durable protection. In contrast, the U.S. and other low-disease-risk countries use the DTaP vaccine, a subunit version that tends to cause fewer short-term side effects but may require more booster doses to maintain immunity.

In regions where disease exposure is high and access to advanced medical care is limited, global health experts often recommend DTPw because of its broader and longer-lasting protection. In response to Kennedy’s accusations, Gavi stated that its “utmost concern is the health and safety of children” and that global immunization experts continue to recommend DTPw for infants in high-risk settings after reviewing all available data.

Why is MWEG following this issue?

One of MWEG’s core principles states that “Economic and social inequity damages the moral fabric of societies and weakens democratic governments. People should act freely to implement measures that promote equality of opportunity for their fellow human beings (see Alma 4:12-13, 3 Nephi 6:9-16, and D&C 49:20).” Vaccine restrictions and reduced funding can prohibit equal opportunity for people inside and outside the U.S.

Conversely, to be attuned to the needs of others and to help provide is a type of ministering. Camille N. Johnson, Relief Society general president of the Church of Jesus Christ of Latter-day Saints, summarized this idea, saying, “Whenever we do anything to bring relief to others — temporal or spiritual — we are bringing them to Jesus Christ and will be blessed to find our own relief in Him.” While some relief comes through individuals, other forms of relief, like the prevention of diseases by vaccines, require a systems or government approach.

This article was written by Natasha Rogers, researcher and writer for Mormon Women for Ethical Government, with Jill Fairholm, MWEG's family and well-being program specialist.