A new study about a vaccine is happening. It is in Guinea-Bissau. The US government is giving money for it. This is $1.6 million.
The US Centers for Disease Control and Prevention changed its advice. Now, they say the hepatitis B vaccine for babies is a choice. This is new advice. Some people think this is because Robert F. Kennedy Jr. is worried. He is worried about vaccine safety.
Guinea-Bissau is in West Africa. Many adults there have hepatitis B. Health experts are worried about this study. They say it is not good. They say it is risky.
These are big changes for vaccines. Health Secretary Kennedy Jr. wants these changes. He also stopped money for Gavi. Gavi helped many children get vaccines. This work saved lives.
The reason for stopping money is a study from 2018. This study was about another vaccine. It suggested a link to more deaths. But later, a different study had different results.
Kennedy Jr. believes vaccines can cause harm. This belief is changing US policy. Some people think these actions are not fair. They could make people trust the US less. This could hurt global health.