From the Guidelines
Yellow fever vaccine can cause mild symptoms in some individuals, typically appearing within 3-7 days after vaccination, and it is essential to seek immediate medical attention if severe symptoms develop. Common side effects include low-grade fever, headache, muscle aches, and soreness at the injection site that usually last 1-3 days, as reported in a study published in 2010 1. Taking acetaminophen or ibuprofen can help manage these symptoms. More serious reactions are rare but may include severe allergic reactions (anaphylaxis), neurological problems, or organ system failure (occurring in fewer than 1 in 250,000 people) 1. These symptoms occur because the vaccine contains a live but weakened form of the yellow fever virus that stimulates your immune system to develop protection. While experiencing mild symptoms indicates your body is building immunity, it is crucial to seek immediate medical attention if you develop high fever, severe headache, confusion, or yellowing of the skin after vaccination. People with egg allergies, compromised immune systems, or those who are pregnant should consult their healthcare provider before receiving this vaccine, as they may have increased risk of complications 1. Some key points to consider:
- The vaccine can cause mild symptoms, such as low-grade fever, headache, and muscle aches, which are usually self-limiting and can be managed with over-the-counter medications.
- Serious reactions, such as anaphylaxis, neurological problems, or organ system failure, are rare but can be life-threatening.
- The risk of serious adverse events is higher in certain individuals, such as those with egg allergies, compromised immune systems, or pregnancy.
- It is essential to consult a healthcare provider before receiving the vaccine, especially if you have any underlying medical conditions or concerns.
From the Research
Yellow Fever Vaccine Symptoms
- The yellow fever vaccine is considered one of the safest vaccines, but it can rarely cause invasive and disseminated disease in some otherwise healthy individuals, with high lethality 2.
- Serious adverse events associated with the yellow fever vaccine include meningoencephalitis, which can occur in older children and adults, but with a good prognosis 2.
- Rare reports of severe adverse events following vaccination have raised concerns about the vaccine's safety, including anaphylaxis, yellow fever vaccine-associated neurotropic disease, and yellow fever vaccine-associated viscerotropic disease 3.
- The risk of serious adverse events after vaccination is higher in males and in persons aged 60 years or older 3, 4.
- The reporting rates of serious adverse events were significantly higher among vaccinees aged 60 years or older than among those 19-29 years of age 4.
- Efforts are being made to develop a safer yellow fever vaccine, including an inactivated vaccine or a vaccine prepared with the vaccine virus envelope produced in plants 2.
Risk Factors
- Individual host factors are thought to contribute to the risk of serious adverse events associated with the yellow fever vaccine, although the exact causes are largely unknown 2.
- Advanced age is considered a risk factor for serious adverse events, and vaccination should be limited to persons traveling to areas where the risk of yellow fever is expected to exceed the risk of serious adverse events after vaccination 3, 4.
Vaccine Safety
- Despite the risk of serious adverse events, the yellow fever vaccine is considered the best way to avoid yellow fever, a disease of high lethality, and should be used routinely in endemic areas and in people from non-endemic areas who could be exposed, according to a careful risk-benefit analysis 2, 3, 4.