What is the yellow fever vaccine?

• The yellow fever vaccine is a live attenuated vaccine that protects against mosquito-borne diseases such as yellow fever. It is highly effective and provides lifelong immunity.
• Who should receive the yellow fever vaccine? This includes people who have traveled to or reside in Central and South African countries, those who have traveled from high-risk countries, and those whose work involves direct exposure to the yellow fever virus.
• Side effects of the yellow fever vaccine can include fever, body aches, pain, swelling, and redness at the injection site. In some cases, allergic reactions may include hives, facial swelling, bronchospasm, and more severe symptoms in certain groups.

When traveling to certain countries, in addition to preparing air tickets and accommodation, it's crucial to prepare your body for local diseases, especially yellow fever. Yellow fever vaccination is a preventative measure against yellow fever, a disease transmitted by mosquitoes and found primarily in Africa and South America. Let's look at what the yellow fever vaccine is and its potential side effects.

What is the Yellow Fever Vaccine?

The Yellow Fever Vaccine is a live attenuated vaccine that protects against mosquito-borne viral infections such as yellow fever. It is highly effective and long-lasting. A single subcutaneous injection can provide up to 99% immunity within 30 days and offers lifelong protection. This vaccine is essential for anyone traveling to Africa and South America.

What is Yellow Fever?

Yellow fever is a contagious disease transmitted by mosquitoes using an arbovirus. It is most common in Africa and South America. The incubation period is approximately 3-6 days. Most patients experience flu-like symptoms such as high fever, headache, and chills, which resolve on their own within a few days. However, in severe cases, the disease can progress to a life-threatening second stage, characterized by liver and kidney dysfunction, jaundice (yellowing of the skin and eyes), and internal bleeding.

Who should receive the Yellow Fever Vaccine?

• Individuals traveling to endemic areas, or residing in Central and South Africa, which are high-risk areas.
• Individuals traveling from high-risk countries. Travelers from countries declared by the World Health Organization (WHO) to have yellow fever outbreaks are required to be vaccinated to prevent the spread of the disease.
• Individuals working in laboratories, staff, or researchers who work directly with the yellow fever virus should also be vaccinated to ensure safety and prevent infection from their work.

Who should be cautious/should not receive the yellow fever vaccine?

• Those with a history of allergy to eggs or egg protein, gelatin, or a history of severe allergic reactions to a previous yellow fever vaccine, as the vaccine is made from chicken embryos.
• Infants under 6 months of age should not receive the vaccine due to the increased risk of encephalitis.
• Those aged 60 years and older are more likely to experience severe side effects from the yellow fever vaccine than other age groups.
• Infants aged 6-9 months, pregnant women, and breastfeeding women should only be considered for the yellow fever vaccine if travel to an endemic area is absolutely necessary and mosquito bites cannot be prevented.

What are the side effects and symptoms after receiving the yellow fever vaccine?

• Common side effects include
• Fever
• Body aches
• Pain, swelling, and redness at the injection site
• Acute allergic reactions
• Hives
• Facial swelling
• Bronchoconstriction
• Neurological side effects
• Encephalitis
• Meningitis
• Acute myocardial infarction (paralysis)
• Organ dysfunction – this is the highest risk and can be life-threatening due to organ failure.

How often and how many doses of the yellow fever vaccine are needed?

A single dose of the yellow fever vaccine provides lifelong immunity, eliminating the need for boosters. This results in the International Concomitant Vaccination Certificate (ICVP) being valid for life as well. However, travelers must receive the vaccine at least 10 days prior to departure to allow immunity to take effect and comply with international regulations.

How long does the yellow fever vaccine last?

Currently, the World Health Organization (WHO) confirms that a single dose of the yellow fever vaccine provides lifelong immunity, eliminating the need for boosters every 10 years as in the past. The yellow ICVP (Infectious Vaccination Certificate) booklet is valid as proof of travel for life.

Which countries require yellow fever vaccination?

South America

• Argentina
• Brazil
• Bolivia
• Colombia
• Ecuador
• Guyana
• French Guiana
• Panama
• Peru
• Venezuela
• Suriname
• Trinidad and Tobago
• Paraguay

Africa

• Angola
• Benin
• Burkina Faso
• Burundi
• Cameroon
• Central African Republic
• Chad
• Congo
• Côte d'Ivoire
• Ethiopia
• Gabon
• Gambia
• Ghana
• Guinea
• Guinea-Bissau
• Equatorial Guinea
• Kenya
• Liberia
• Mali
• Mauritania
• Niger
• Nigeria
• Senegal
• Sierra Leone
• Sudan
• South Sudan
• Togo
• Uganda
• Democratic Republic of Congo (DR Congo)

Yellow fever vaccination available at Viphavadee Hospital.

For those planning a trip to South America or Africa, yellow fever vaccination is required at least 10 days prior to departure. Yellow fever vaccinations are available at Vibhavadi Hospital. Here, doctors are ready to provide advice and explain about yellow fever, an endemic disease, ensuring you travel in good health.

In summary

What is the yellow fever vaccine? It's a live attenuated vaccine for those traveling to endemic areas in Africa and South America. It protects against a life-threatening disease transmitted by mosquitoes. A single injection provides lifelong immunity and protection, as confirmed by the WHO. It's recommended to get vaccinated at least 10 days before travel. However, be aware of potential side effects in young children, those over 60 years old, and those with a history of severe egg allergy, as the vaccine is produced from chicken embryos.
Being vaccinated ensures safe travel and compliance with international regulations. If you need a yellow fever vaccine, we recommend consulting and receiving it at Vibhavadi Hospital, where expert doctors will provide appropriate diagnosis and treatment.