World
Health Organization - directing and coordinating authority on
international health work that strives to bring the highest level of
health to all peoples.
·
What
the Heck is an Antibiotic? - antibiotics do not harm viruses, but
rather have the ability to kill bacteria. Learn more in this expanded
definition from John C. Brown.
National
Network for Immunization Information - provides the public, health
professionals, policy makers, and the media with up-to-date,
scientifically valid information related to immunization.
NEW YORK (Reuters Health) - Three newly published reports show that in a handful
of cases, people receiving the yellow fever vaccine have died shortly after
being immunized. However, experts say that the risks associated with yellow
fever are much greater than the risk of suffering a fatal reaction to the
vaccine, which appears to be a very rare event.
Yellow fever is a mosquito-borne ailment that results in a high fever, a
yellowing of the skin due to liver damage (jaundice) and bleeding from the
gums, the intestines and the kidneys. The disease is most commonly found in
tropical and subtropical regions of Africa and South America, and is fatal in
approximately 20% to 50% of victims--with the elderly often at a greater risk
of death.
The three studies published in the July 14th issue of the British journal,
The Lancet, report on deaths associated with the yellow fever vaccine in
three countries--three deaths in the US, two deaths in Brazil and one death
in Australia. However, experts caution that yellow fever is a potentially
life-threatening ailment and the benefits of the vaccine outweigh the risks
in the vast majority of people who are at risk of contracting the illness.
``The bottom line is that the outcomes that were reported in The Lancet
are very rare events,'' said Dr. Martin S. Cetron, co-author of one of the
studies, who conducts research at the Centers for Disease Control and
Prevention (news
- web
sites) (CDC) in Atlanta, Georgia. ``The vaccine has been used for over 60
years and has been safe and effective not only to people living in endemic
areas but to travelers to those regions (where yellow fever is common) as
well,'' he told Reuters Health.
The yellow fever vaccine contains a virus that is a weakened version of
live, wild-type yellow fever and has been given in an estimated 400 million
doses worldwide since its development in the 1930s.
In the first report, Dr. Pedro. Vasconcelos, of the WHO Collaborating
Centre for Reference and Research on Arbovirus in Brazil, and colleagues note
that a 5-year-old girl and a 22-year-old woman each died within a week of
being vaccinated for yellow fever.
In the second report, lead author Dr. Michael Martin of the CDC and
colleagues report on the deaths of three Americans--all over the age of 63. A
fourth patient who became very ill 9 days after receiving a yellow fever
vaccine recovered. In the last report, a letter to The Lancet, Dr. Raymond C.
Chan of the South Western Area Pathology Service in Sydney, Australia, and
colleagues detail the death of a 56-year-old man who died within 2 weeks of
receiving the yellow fever vaccine.
The patients in Brazil and Australia had symptoms similar to those seen in
patients with yellow fever, while the US patients had some yellow fever
symptoms, in addition to multiple systemic problems, involving the liver,
kidney, lungs and brain. The researchers could find no specific link between
the cases, such as a certain lot of vaccine or patient characteristic.
``We could not find a common link that would suggest defects in the vaccine,''
Cetron told Reuters Health.
Instead Cetron suggests that there may have been some as yet unknown
factor about the individuals who received the vaccine that caused the adverse
reaction.
While the exact frequency of adverse events for those receiving the yellow
fever vaccine is not known, Cetron stressed that, between 1990 and 1998, a
period where 1.6 million doses of the yellow fever vaccine were given out to
Americans, only these four cases were documented.
The US researchers conclude that the vaccine should continue to be used,
but that ``care should be taken in recommending yellow fever vaccine for
older people; for travellers, itineraries should be scrutinized and vaccine
should be provided only to those travelling to areas reporting yellow fever
activity or areas in the yellow fever endemic zone.''
``Despite the severity of these reactions, overall the findings indicate
that no change in practice regarding yellow fever vaccination is needed for
endemic or epidemic areas,'' Dr. Philippe Marianneau of the Pasteur Institute
in Lyon, France and colleagues write in an accompanying commentary.
``There are no obvious correlations between the cases in these three
reports,'' they add.
``The use of (the yellow fever vaccine) remains highly advisable'' for
people living in or traveling to regions where yellow fever exists,
Marianneau and colleagues conclude.
SOURCE: The Lancet 2001;358:84-85, 91-97, 98-104, 121-122.
ALL
INFORMATION, DATA, AND MATERIAL CONTAINED, PRESENTED, OR PROVIDED HERE IS FOR
GENERAL INFORMATION PURPOSES ONLY AND IS NOT TO BE CONSTRUED AS REFLECTING THE
KNOWLEDGE OR OPINIONS OF THE PUBLISHER, AND IS NOT TO BE CONSTRUED OR INTENDED
AS PROVIDING MEDICAL OR LEGAL ADVICE. THE DECISION WHETHER OR NOT TO
VACCINATE IS AN IMPORTANT AND COMPLEX ISSUE AND SHOULD BE MADE BY YOU, AND YOU
ALONE, IN CONSULTATION WITH YOUR HEALTH CARE PROVIDER.
"A foolish faith in authority is the worst enemy of truth."
-- Albert Einstein, letter to a friend, 1901
"I know of no safe depository of the ultimate powers of the society but the people themselves, and if we think them not enlightened enough to exercise control with a wholesome discretion, the remedy is not to take it from them, but to inform their discretion by education."
-- Thomas Jefferson, letter to William C. Jarvis, September 28, 1820
"What's the point of vaccination if it doesn't protect you from the unvaccinated?"
-- Sandy Gottstein
"Who gets to decide what the greater good is and how many will be sacrificed to it?"