Yellow fever vaccine: reactions, price, when and where to take

With the beginning of summer, the number of mosquitoes increases in all tropical regions. The presence of these insects can bring several health risks, such as dengue , zika and yellow fever .

One way to protect against yellow fever is through vaccination. It is offered free of charge by SUS and guarantees total immunity to the disease.

Find out more about how and where to get vaccinated in the following text!


What is the yellow fever vaccine?

The yellow fever vaccine is an attenuated version of the live virus that causes the disease.

Between 10 and 30 days, 95% to 99% of vaccinated people will be protected against yellow fever.

It is administered subcutaneously, usually in the arm region, and is painless. It is distributed free of charge by the Unified Health System (SUS) in health posts throughout Brazil and is currently part of the National Vaccination Calendar of many states.

For the World Health Organization (WHO), vaccination is considered the most effective way to prevent and combat yellow fever. Above all, because it does not pose great risks to the individual.

The chances of a person developing yellow fever because of the vaccine are low, but they occur because the vaccine is nothing more than a weakened version of the live virus.

Upon contact with this material, which is practically harmless, the body begins to create protections against the real virus.

However, although it is safe, the vaccine is contraindicated for pregnant women, the elderly and children under 9 months of age, except in situations of risk, when this period may be shortened and the child may be vaccinated after 6 months.

Until April 2017, the Ministry of Health of Brazil advised the population to take 2 doses of the vaccine. As of this date, the country decided to follow the WHO guidelines and started to adopt a scheme in which only 1 vaccine is needed to guarantee immunity.

It is worth remembering that the vaccine itself has not changed, so anyone who has already taken the vaccine and was waiting to take the second dose does not need to worry anymore, as he is already immunized.

What is yellow fever?

Yellow fever is a serious viral infection transmitted, usually, by the Haemagogus mosquitoes and the Sabethes (wild yellow fever) and the Aedes aegypti mosquito (urban yellow fever).

Yellow fever of the urban type has not occurred in Brazil since 1942, and currently it is the wild type that is circulating.

In this case, the mosquito bites the monkeys and transmits the disease. The disease affects humans when an unimmunized person goes to a region where the mosquitoes circulate and is bitten.

Its main features are high fever and yellowing on the body (jaundice), which is why it gets its name.

People who develop the disease may experience symptoms such as:

  • High fever;
  • Chills;
  • Tiredness;
  • Headache;
  • Muscle pain;
  • Sickness;
  • Vomiting.

It is caused by an arbovirus of the genus Flavivirus, of the family Flaviviridae, and its consequences can be fatal. About 15% of patients who contract the yellow fever virus develop, in the first 48 hours, the most severe phase of the disease, known as toxic.

Internal hemorrhages, multiple organ failure, blood in the vomit and feces, kidney and liver failure, delusions and seizures may occur . This variation of the disease can lead the patient to a coma or death.

So don’t take any chances, be up to date with your vaccines!

What is the vaccine for?

The yellow fever vaccine is nothing more than a way to immunize the patient against the yellow fever virus . According to the WHO, it is the most effective method of preventing the disease. Through it, immunity is acquired in just 30 days in 99% of vaccinated people.

In addition to being a way to immunize the patient individually, it is also, from a structural point of view, an effective way to control epidemics.

Since it is transmitted by a mosquito that is very common in cities, yellow fever is a disease that has the potential to spread very easily. And as its fatality rate is high, governments and institutions around the world are very concerned about keeping the disease under control, preventing it from reaching a large number of individuals.

The most effective way to prevent the disease from spreading to more regions and causing more victims, affecting not only people’s lives, but also the structural functioning of society as a whole, is through vaccination.

What is the fractional dose?

The fractional dose of the yellow fever vaccine is nothing more than a smaller and more diluted dose than the common one. It has approximately 1/5 of the standard dose (0.5mL), that is, 0.1mL, making it possible to vaccinate up to 5 people with a single normal dose of the vaccine.

To date, it is believed that the fractional dose guarantees immunity against the yellow fever virus for up to 8 years, however, this number is questioned by infectologists around the country.

It should be noted that the fractional dose is no less effective than the standard dose. What changes from one to the other is the time of action. While the common dose is unique, that is, it is only one for life, the fractional dose will guarantee immunity for a shorter period of time.

Why do fractionation?

The World Health Organization (WHO) recommends that the vaccine be fractionated only in emergency situations. When there is an outbreak of yellow fever in some region and it is necessary that a large number of people be vaccinated, fractionation is an effective option to prevent the shortage of the vaccine.

This technique is adopted because, in emergency situations, a kind of collective hysteria occurs and all people rush to the hospitals in search of the vaccine. This can cause vaccine stocks in hospitals to be consumed overnight, leaving many people without access to adequate protection.

Vaccinating all people with a single dose in emergency situations is not effective in combating the epidemic, from a structural point of view. This is because fewer people will be immunized, making the disease spread to more regions more easily.

This is why the fractional dose was adopted in Brazil in early 2018. It is better to vaccinate more people, even if immunity is guaranteed for a shorter period of time, and to make sure that the disease will not spread to other regions, than to fully immunize a smaller portion of the population and run the risk of increasing the epidemic.

Which people should receive the standard dose even in the cities where the fractionation is taking place?

The people who should receive the full dose of the vaccine even when they are in places where fractionation is taking place are:

  • HIV carriers with a CD4 count greater than 350 per µL;
  • People who have finished chemotherapy or radiation therapy;
  • People with blood disorders, such as thalassemia and anemia;
  • Pregnant women;
  • Children 9 months and under 2 years old;
  • International travelers, since the International Health Regulations (IHR) did not authorize the use of the fractional dose for the issuance of the International Certificate of Vaccination and Prophylaxis (CIVP). In such cases, at the time of vaccination, the citizen must present the proof of travel (ticket of airline ticket or hotel, invitation to participate in events, among others) to countries that require the CIVP.

People who have received the fractional dose and, for some reason, need to receive the standard dose, can do the application 30 days after the first immunization.

How does it work?

The vaccine is nothing more than a weakened version of the yellow fever virus. The presence of this material in the body stimulates the body to produce antibodies for its own protection against the real virus. It is this effect that guarantees immunity.

It is applied in a very simple, painless and fast way, providing immunity to the patient after 10 days of application, which is done subcutaneously, in the arm region, with the dose of 0.5mL.

In the fractionated dose, a smaller amount of the immunobiological agent is applied, which guarantees the protective effect for a shorter period of time, but which is still important in risk situations to prevent epidemics.

When should it be taken?

The vaccine, in general, should be taken by all individuals older than 9 months of age and living in at-risk regions or who receive a recommendation for immunization.

People who do not live in a high-risk region but who will be traveling to these places should also get the vaccine. In addition, people who will travel to countries that require CIVP are also required to take if they wish to enter the country. See what these countries are in the topic “Countries that require CVIP”.

Elderly, pregnant women, lactating women and people with a disease or who use a medication that causes immunosuppression can only get the vaccine after talking to a doctor and assessing the risks and benefits related to immunization.

Can babies get the vaccine?

The World Health Organization recommends that babies only be exposed to the yellow fever vaccine after 9 months of age . The exception is found in cases of an epidemic, that is, in which the child is at direct risk of contracting the disease.

In such cases, the period can be advanced by up to 3 months and the child can be medicated at 6 months of age. Before that, the risks involved in applying the vaccine are still evident and the chances of neurological damage must be considered.

What are the places at risk of yellow fever?

Regions of forests and rivers are the main places of risk. Those who do not live in a risky region should be aware when traveling to the following places:

  • North region states (Acre, Amazonas, Roraima, Rondônia, Pará, Amapá and Tocantins);
  • States in the Midwest region (Mato Grosso, Mato Grosso do Sul, Goiás and Distrito Federal);
  • State of Maranhão;
  • Southwest of Piauí;
  • West and south end of Bahia;
  • Minas Gerais state;
  • West of São Paulo;
  • North of Espirito Santo;
  • Some municipalities in the South region (Paraná, Santa Catarina and Rio Grande do Sul);

People who wish to travel outside of Brazil should get the vaccine if they wish to go to:

  • Angola;
  • Argentina;
  • Benin;
  • Bolivia;
  • Burkina Faso;
  • Burundi;
  • Cameroon;
  • Chade;
  • Colombia;
  • Congo;
  • Costa do Marfim;
  • Ecuador;
  • Ethiopia;
  • Gabon;
  • Gambia;
  • Win;
  • Guiana;
  • French Guiana;
  • Guinea;
  • Equatorial Guinea;
  • Guinea Bissau;
  • Liberia;
  • Mali;
  • Mauritania;
  • Niger;
  • Nigeria;
  • Panama;
  • Paraguay;
  • Peru;
  • Kenya;
  • Democratic Republic of Congo;
  • Central African Republic;
  • Rwanda;
  • Sao Tome and Principe;
  • Senegal;
  • Sierra Leone;
  • Somalia;
  • Sudan;
  • Suriname;
  • Tanzania;
  • Togo;
  • Trinidad Tobago;
  • Uganda;
  • Venezuela;
  • Zambia.

International Certificate of Vaccination and Prophylaxis (CIVP)

Travelers to countries with endemic areas of yellow fever may end up needing the International Vaccination Certificate.

The demand for these roles can be made by countries with or without endemic areas, because in some regions, such as the Indian Subcontinent and Southeast Asia, although the disease does not exist, there are transmissions capable of starting an epidemic.

You can check the International Certificate requirement at the Brazilian embassies or consulates of the destination countries. Always  check with embassies before traveling, not only to not miss a trip, but also to protect yourself from possible infections!

How to get the International Vaccination Certificate?

Obtaining the International Certificate of Vaccination and Prophylaxis (CIVP) can be a difficult task, as many cities in Brazil do not have Anvisa guidance centers, where you must go to get the document.

This situation, however, is about to change, since Anvisa, in partnership with the Secretariat of Information Technology of the Ministry of Economy (future Secretariat of the Digital Government), intends to implement, at the end of January, a new system, in which the citizen who wishes to travel can issue the CIVP at home.

Find out below, how to get the certificate today, and what the online alternative will be like, which is expected to start operating on January 29, 2019:

How to take the CIVP in person?

To obtain the International Certificate of Vaccination and Prophylaxis (CIVP), travelers, today, must go to an orientation center maintained by Anvisa at airports and ports or in associated services after taking the vaccine.

In some hospitals and private clinics, vaccination is carried out on the spot, and the document is delivered shortly thereafter.

How to get CIVP online?

As of January 29, 2019, the estimated date for launching the platform, after taking the vaccine, the citizen must register on the government services portal and send the request together with a vaccination voucher or wallet.

Then, the request will be analyzed by Anvisa, which checks the veracity of the documents and crosses data, such as CPF, number and batch of the vaccine. If inconsistencies are found, the agency may contact the health unit responsible for the vaccination.

It is not yet known how long Anvisa will take to analyze the information, but the expectation, however, is that the process will last up to 1 day. After approval, the user will receive the certificate online so that it can be printed at home.

People who have difficulty in accessing the digital process, foreigners without CPF, illiterates and the indigenous population must take the CIVP in person.

Countries requiring CIVP

Countries are divided into two groups: those that require the certificate only from people living in Brazil and other risk areas, and those that require it from any traveler. Check out:

Countries requiring certificates from people living in risk areas

  • Afghanistan;
  • South Africa;
  • Albania;
  • Saudi Arabia;
  • Algeria;
  • Antigua and Barbuda;
  • Australia;
  • Bahamas;
  • Bahrain;
  • Bangladesh;
  • Barbados;
  • Belize;
  • Benin;
  • Bhutan;
  • Bolivia;
  • Bonaire;
  • Botswana;
  • Brunei;
  • Burkina Faso;
  • Cape Verde;
  • Cameroon;
  • Cambodia;
  • Kazakhstan;
  • Chade;
  • China (except Hong Kong and Macau);
  • Singapore;
  • Colombia;
  • North Korea;
  • Costa Rica;
  • Cuba;
  • Curaçao;
  • Djibouti;
  • Dominica;
  • Egypt;
  • The Savior;
  • Ecuador;
  • Eritreia;
  • Ethiopia;
  • Fiji;
  • Philippines;
  • Gambia;
  • Granada;
  • Guadalupe;
  • Guatemala;
  • Guinea;
  • Equatorial Guinea;
  • Guiana;
  • Haiti;
  • Honduras;
  • Pitcairn Islands;
  • Solomon Islands;
  • Indonesia;
  • Will;
  • Iraq;
  • Jamaica;
  • Jordan;
  • Laos;
  • Lesotho;
  • Libya;
  • Madagascar;
  • Malawi;
  • Malaysia;
  • Maldives;
  • Malta;
  • Martinique;
  • Mauritania;
  • Mauritius;
  • Mayotte;
  • Montserrat;
  • Mozambique;
  • Myanmar;
  • Namibia;
  • Nauru;
  • Nepal;
  • Nicaragua;
  • New Caledonia;
  • Nigeria;
  • Niue;
  • Oman;
  • Panama;
  • Pakistan;
  • Paraguay;
  • French Polynesian;
  • Kenya;
  • Kyrgyzstan;
  • Kiribati;
  • Meeting;
  • Rwanda;
  • Saint Bartholomew;
  • Saint Kitts and Nevis;
  • Saint Lucia;
  • Saint Martin / Sint Maarten;
  • Saint Vincent and the Grenadines;
  • Samoa;
  • Sao Tome and Principe;
  • Santa Helena,;
  • Senegal;
  • Seychelles;
  • Somalia;
  • Sri Lanka;
  • Sudan;
  • Suriname;
  • Swaziland;
  • Thailand;
  • Timor-Leste;
  • Trinidad and Tobago;
  • Tristan da Cunha;
  • Tanzania;
  • Uganda;
  • Vietnam;
  • Wallis and Futuna;
  • Zambia;
  • Zimbabwe.

Countries requiring CIVP from all travelers

  • Angola;
  • Burundi;
  • Central African Republic;
  • Congo;
  • Costa do Marfim;
  • Democratic Republic of Congo (ex-Zaire);
  • French Guiana;
  • Gabon;
  • Win;
  • Guinea Bissau;
  • India;
  • Liberia;
  • Mali;
  • Niger;
  • Sierra Leone;
  • Suriname;
  • Togo.

Who can not get the yellow fever vaccine?

Although it is safe and efficient, the yellow fever vaccine should be avoided by some groups. In such cases, the guideline for prevention is to avoid mosquito bites through the use of long – sleeved shirts and long pants, mosquito nets and repellents.

Check out these risk groups:


The main contraindication is for people who have a compromised immune system, whether due to some disease, such as AIDS , autoimmune diseases and Addison’s disease, or because of the use of immunosuppressive drugs, such as high-dose corticosteroids or chemotherapy.

This is because, since the yellow fever vaccine is an attenuated vaccine, that is, its infectious power is reduced, it still has a chance, even if very small, of leading to a future infection by the yellow fever virus.

In normal patients, these chances are negligible, almost nil. Patients with weakened immune systems are more likely to develop the virus.

Pregnant and lactating women

Pregnant women should not receive the vaccine, as it can cause serious complications for the development of the baby’s neurological system.

Mothers who breastfeed their children under 6 months of age should also not receive the vaccine, except in very specific situations, since, after receiving the dose, the mother must go 10 days without breastfeeding.

Severe egg allergy

People who have an egg allergy should not get the vaccine because the virus is grown in embryonated chicken eggs.

Babies under 6 months of age

The weakened vaccine virus can cause neurological problems for young babies.


As much as the risks are not so great, the elderly, as well as babies, tend to have a more fragile immune system, and it is recommended to think twice before taking the vaccine.


The risks related to the yellow fever vaccine are low and involve the development of yellow fever in most cases.

To get an idea of ​​the safety of the vaccine, figures from the Epidemiological Surveillance Manual for Adverse Events Post-Vaccination, from the Ministry of Health, collected between 2001 and 2003, show that there were only 7.6 cases of adverse reactions caused by the vaccine registered at every 1 million doses applied.

In addition, the consensus among experts is that the average risk of complications caused by the vaccine is 3 per 1 million doses applied, or 0.3 per 100,000.

For people to whom the vaccine is indicated, there is no relevant chance that the vaccine will cause problems and it can be considered completely safe.

Yellow fever vaccine reactions

The yellow fever vaccine can have a number of side effects, but they are extremely rare. Only about 5% of people who get the vaccine end up developing any side effects.

They usually start to occur between 5 to 10 days after vaccination. Symptoms such as fever, headache or reactions at the application site are rare, but they can happen.

A severe allergic reaction after vaccination, for example, occurs in approximately 1 in 130,000 doses, while a reaction in the central nervous system, called encephalitis , occurs in 1 in 250,000 doses, on average.

Check out the side effects that the vaccine can cause:

Mild reactions

A small portion of people who get vaccinated will experience some mild side effects, which usually appear around 5 days after vaccination and disappear naturally, such as:

  • Fever;
  • Headache;
  • Muscle pain;
  • Pain at the application site;
  • Swelling, blemishes and redness at the application site.

The effects of headache, malaise and fever do not usually last more than 3 days. In case of doubts, however, go back to the vaccination site to find out the causes of these problems.

Serious reactions

Serious side effects are even more rare ! When in doubt, however, always contact your doctor.

Among the main serious side effects are:

Severe allergic reaction

It occurs in people who are allergic to eggs, as the vaccine is grown on the egg white. It is very rare and occurs in 1 in 131 thousand doses.

Central nervous system reactions

Also very rare, this reaction can occur 1 out of every 250 thousand doses.

Multiple organ involvement with the yellow fever virus

Even more rare, this side effect can be seen in approximately 1 case per 300,000 doses. In people over 60, however, that number drops and affects about 1 in every 50,000 doses.

Deaths due to vaccine reaction

According to the São Paulo Department of Health, there were only 3 cases of death caused by an adverse reaction to the vaccine in a period of 1 year, between January 2017 and January 2018.

The patients who died, according to the institution, had no evidence of previous diseases and were adults under 60 years of age.

The vaccine only leads to death when the body cannot contain the multiplication of the attenuated virus that was injected by the vaccine, causing it to start attacking the patient’s body.

This can lead to viscerotropic disease , which is when vaccination causes dysfunction in multiple organs. These reactions can progress to liver and heart failure, cause clotting problems, lead to fulminant hepatitis and, later, to death.

This type of problem tends to happen much more in immunosuppressed or immunosuppressed people, however, it is not possible to say that completely healthy patients cannot suffer this type of complication.

About half of people who develop yellow fever in severe stages do not survive.

Drug interaction

Chemically speaking, there is no drug interaction with the vaccine. It does not interact directly with any medication.

However, people taking immunosuppressive drugs should not get the vaccine , as low immunity can favor the appearance of dangerous side effects that can even lead to death.

Although there are no chemically drug interactions, it is extremely important that you see a doctor before taking the vaccine and tell him about all the medicines you have been using to ensure that the vaccine is safe for you.

Price: how much does the yellow fever vaccine cost?

The yellow fever vaccine is distributed by the Unified Health System (SUS) and can be taken free of charge at health centers throughout the municipalities around Brazil. For those who do not want to use the Single System, it can be purchased in private clinics with its price ranging between R $ 100 and R $ 180 .

Common questions

If I lost my vaccination card and I don’t remember if I got the vaccine, should I take another dose?

If you have lost your vaccination card and do not remember whether or not you have taken the vaccine doses, you should seek the health service you usually visit and try to retrieve your history.

If this is not possible, the recommendation is that you do the vaccination normally.

What happens if many people decide to get the vaccine unnecessarily?

Individually, there are no major implications for getting the vaccine. As stated earlier, the risks involving vaccination are low.

However, if people start to move en masse in search of the vaccine, it may happen that the stocks of the vaccine will decrease, causing people who really need the vaccine to be without it.

So, if you don’t live in a high-risk region and don’t plan to travel to any, don’t get the vaccine. There is no reason for you to worry about this at the moment.

Can blood donors get the vaccine?

Yes and no. Calm! It’s simple. People who intend to donate blood, in reality, must wait 30 days after vaccination to perform the procedure.

This waiting time serves to prevent the live inoculated virus, which circulates in the donor’s bloodstream for weeks after vaccination, from ending up in a patient whose immune system is compromised, causing adverse reactions.

It is a preventive action that is part of international protocols and serves to guarantee the integrity of patients at risk.

Can I drink right after I get vaccinated?

Yea! There are no problems in associating alcohol consumption with the vaccine.

Is there a drug interaction?

There is no problem with drug interactions between the vaccine and other drugs, so you can take any type of medication afterwards.

Is it necessary to avoid making sudden movements with the arm after vaccination?

There should be no concern with movements after vaccination.

Who gets yellow fever must have jaundice?

Not necessarily . There are milder forms of the disease that do not cause jaundice (yellowish color on the skin and eyes).

Can people who have been ill for a short time take it?

For people who have been ill for a short time, it is necessary to have a medical evaluation.

Is there a relationship between climate change (aka “global warming”) and the return of yellow fever?

Climate change cannot be blamed for the reappearance of the disease. However, when there is an increase in temperature and rainfall, the population of mosquitoes that transmit the disease tends to increase as well.

Is there a need for any fasting to get the vaccine?

No. There is no need to fast before getting the vaccine.

What is the chance that an infected person will die?

If we consider the severe form of the disease, the chances are very high, reaching up to 90%.

However, considering that the disease has milder forms, we can say that the mortality rate is between 20% and 50% among people who develop the severe type of the disease.

How long does the yellow fever vaccine last?

A single standard dose of the yellow fever vaccine is enough to make a person immune for life. People who have taken the fractional dose are immune for 8 years, and must take the standard dose to be immune.

Despite the low risks, the yellow fever vaccine should not be taken by everyone. Not only because certain groups are more sensitive to its effects, but because it is good to keep the vaccine stocks up to date to prevent epidemic cases.

Is that you? Have you ever had the yellow fever vaccine? Tell us how it went in the comments!