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The existing injectable cholera vaccines do not prevent the development of
the carrier state or affect the severity of the disease. They do not prevent
the introduction of cholera into a country or interrupt transmission. The
risk to travelers is low. The International Health Regulations abolished the
requirement of a vaccination certificate in June 1973. No country should
require a certificate from travelers arriving from Canada. We provide an
exemption certificate to each traveler which is sufficient to avoid
inconvenience. A new oral cholera vaccine is available in some countries
and is relatively effective for those few travellers at high risk.
There is a new oral Cholera/Traveller's diarrhea vaccine
available. Some travellers may want this to prevent cases of
enterotoxigenic E Coli infections, a common cause of severe travellers
diarrhea. A few such as aid workers or those going to very remote areas with
cholera outbreaks may want it to prevent cholera. Cost $40 per dose 2 doses
required (plus boosters for frequent travellers).
Effective January 1982, smallpox was eliminated as a quarantinable disease.
No country requires a vaccination certificate and distribution of the
vaccine for civilian use was discontinued in May 1983. The last reported
case was 1977.
Information about smallpox and bio-terrorism
Yellow Fever Endemic zones - Africa (WHO CDC)
Yellow Fever Endemic zones - Americas (WHO CDC)
More info onYellow Fever Vaccine from CDC
Yellow fever is preventable by a relatively safe, effective vaccine. All
yellow fever vaccines currently manufactured are live attenuated viral
vaccines.
YF-VAX, the only yellow fever vaccine approved for use in the United States
and Canada, is manufactured by sanofi pasteur.
Studies comparing the reactogenicity and immunogenicity of various yellow
fever vaccines, including those manufactured outside of the United States,
suggest that there is no significant difference in the reactogenicity or
immune response generated by the various vaccines. Thus, individuals who
receive yellow fever vaccines in other countries should be considered
protected against yellow fever.
Recommendations for the Use of Yellow Fever Vaccine for
Travelers
Persons aged ≥9 months of age who are traveling to or living in areas with
risk of yellow fever transmission in South America and Africa should be
vaccinated. In addition, some countries require proof of yellow fever
vaccination for entry. See the following section in this chapter (Yellow
Fever Vaccine Requirements and Recommendations, by Country) for more
detailed information on the requirements and recommendations for yellow
fever vaccination for specific countries.
However, because severe adverse events (see below) can follow yellow fever
vaccination, physicians should be careful to administer the vaccine only to
persons truly at risk of exposure to YFV.
Refer to Yellow Fever Vaccine Recommendations of the Advisory Committee on
Immunization Practices (ACIP) for additional information at
www.cdc.gov/vaccines/pubs/ACIP-list.htm.
Vaccine Dose and Administration
For all eligible persons, a single injection of 0.5 mL of reconstituted
vaccine should be administered subcutaneously.
The International Health Regulations (IHR) published by WHO require
revaccination at 10-year intervals.
Vaccine Safety and Adverse Reactions
Common Adverse Events
Reactions to yellow fever vaccine are generally mild, with 10%–30% of
vaccinees reporting mild systemic adverse events.
Reported events typically include low-grade fever, headache, and myalgias
that begin within days after vaccination and last 5–10 days.
Approximately 1% of vaccinees temporarily curtail their regular activities
because of these reactions.
Severe Adverse Events
Hypersensitivity
Immediate hypersensitivity reactions, characterized by rash, urticaria, or
asthma or a combination of these, are uncommon. Anaphylaxis following yellow
fever vaccine is reported to occur at a rate of 1.8 cases per 100,000 doses
administered.
Yellow Fever Vaccine-Associated Neurologic Disease (YEL-AND)
YEL-AND represents a conglomerate of different clinical syndromes,
including meningoencephalitis, Guillain–Barré syndrome (GBS), acute
disseminated encephalomyelitis (ADEM), bulbar palsy, and Bell’s palsy.
Historically, YEL-AND was seen primarily among infants as
encephalitis, but more recent reports have been among persons of all ages.
The onset of illness for documented cases ranges 3–28 days after
vaccination, and almost all cases were in first-time vaccine recipients.
• YEL-AND is rarely fatal.
The incidence of YEL-AND in the United States is 0.8 per 100,000 doses
administered. The rate is higher in persons ≥60 years of age, with a rate of
1.6 per 100,000 doses in persons 60–69 years of age and 2.3 per 100,000
doses in persons ≥70 years of age.
Yellow Fever Vaccine-Associated Viscerotropic Disease (YEL-AVD)
YEL-AVD is a severe illness similar to wild-type disease,
with vaccine virus proliferating in multiple organs and often leading to
multisystem organ failure and death.
Since the initial cases of YEL-AVD were published in 2001, more than 40
confirmed and suspected cases have been reported throughout the world.
The onset of illness for YEL-AVD cases averaged 3.5 days (range: 1–8 days)
after vaccination. YEL-AVD appears to occur after the first dose of yellow
fever vaccine rather than with booster doses.
The case–fatality ratio for reported YEL-AVD cases is 53%.
The incidence of YEL-AVD in the United States is 0.4 cases per 100,000 doses
of vaccine administered. The rate is higher for persons ≥60 years of age,
with a rate of 1 per 100,000 doses in persons 60–69 years of age and 2.3 per
100,000 doses in persons aged ≥70 years of age.
recent
yellow fever (and cholera) infected areas (CDC WHO)
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