Yellow Fever Outbreak Closes Brazil Gardens, Zoo, and Park

If you plan to visit Sao Paulo Brazil's zoo or botanical garden, you will need to show proof of yellow fever immunization.

Sao Paulo, which is Brazil’s largest city, restricted access to these facilities on January 22, 2018, after a monkey died from yellow fever at a zoo, health officials reported. 

Additionally, Inhotim Art Park, which attracts many international visitors during the Carnival festival in February, are requiring proof of vaccination prior to entering.

The requirements for the International Certificate of Vaccination against yellow fever, are available on the World Health Organization (WHO) International Travel and Health website.

The U.S. Centers for Disease Control and Prevention (CDC), the WHO and the US Embassy in Brazil have updated their vaccination recommendations for persons living in or traveling to Brazil.

Health officials say travelers should plan to get the vaccination before arriving in Brazil as the country is facing a shortage of the vaccine. The yellow fever vaccine "is only effective if received at least 10 days prior to arrival in an at-risk area," the CDC said.

Additionally, the Brazilian Ministry of Health is reporting an increase of confirmed yellow fever cases and deaths in various cities, including Minas Gerais, Sao Paulo, and Rio de Janeiro.

During the first week of 2018, the number of recorded deaths from yellow fever rose from 20 to 53, reported cases rose from 470 to 601, while confirmed cases jumped from 35 to 130.

According to the Brazilian health ministry, 93.6 percent of the total number of confirmed cases are male and the mean age of confirmed cases is 46 years of age. The reported lethality of yellow fever virus in Minas Gerais in the period 2017/2018 is approximately 53.2%.

The WHO said the increasing epizootic cases are a cause for concern throughout Brazil.

"All confirmed cases are likely to have acquired their infections in geographic locations where there are documented epizootics in non-human primates," the WHO said.

"The high number of epizootics and animals concerned indicates a high level of circulation of the virus in ecosystems favorable for transmission."

Brazilian health officials announced a plan for Sao Paulo, Rio de Janeiro, and Bahia states to vaccinate 21.8 million people (16.5 million with the fractional dose and 5.3 million with the standard dose).

Both doses of yellow fever vaccine offer 99% immunity against the virus within 30 days of immunization, and around 80% immunity after 10 days.

A full dose of yellow fever vaccine offers lifelong immunity, while the fractional dose requires future boosters. The fractional dose is also not applicable for travelers to countries requiring the international yellow fever vaccination certificate.

Yellow fever is an acute viral haemorrhagic disease that is endemic in tropical areas of Africa and Latin America. Cases can be difficult to distinguish from other viral hemorrhagic fevers such as arenavirus, hantavirus or dengue.

Symptoms of yellow fever usually appear 3 to 6 days after the bite of an infected mosquito. In the initial phase, they include fever, muscle pain, headache, shivers, loss of appetite, and nausea or vomiting. The "yellow" in the name refers to jaundice that affects some patients.

For most patients, these symptoms disappear after 3 to 4 days.

However, 15% of patients enter a second, more toxic phase within 24 hours of the initial remission when high fever returns, and several body systems are affected, including the kidneys.

Because of a depletion of the FDA approved YF-Vax vaccine until mid-2018, the manufacturer Sanofi Pasteur has worked with the CDC to make an alternative yellow fever vaccine, 17D-204, available in the USA.

The Stamaril vaccine, which is currently available in 70 countries worldwide, has a clinical efficacy profile similar to YF-VAX.

Stamaril is only available at select locations. 

There are sufficient supplies of Stamaril vaccine to meet the yellow fever vaccination needs of the clinics participating in the Expanded Access Program in the US.

The CDC is suggesting people who are contemplating traveling to yellow fever endemic areas should schedule a vaccination appointment at least 2 months before departure.

Once vaccinated, travelers should receive a yellow card called the International Certificate of Vaccination or Prophylaxis (ICVP) to prove that you have had yellow fever vaccine.

Countries such as Brazil now require travelers to show proof of yellow fever vaccination before entering their country.

Providers and patients may also visit the CDC Travelers' Health for information about which countries require yellow fever vaccination for entry.

The CDC Vaccine Price List provides the private sector vaccine prices for general information.  Vaccine discounts can be found here.

Vaccines, like any medicine, can have side effects, says the CDC. You are encouraged to report negative side effects of vaccines to the FDA or CDC.