The
2009 flu pandemic vaccines are the set of
influenza vaccines that have been developed to protect against the
pandemic H1N1/09 virus.
These vaccines either contain inactivated (killed) influenza virus, or
weakened live virus that cannot cause influenza. The killed vaccine is
injected, while the live vaccine is given as a nasal spray. Both these
types of vaccine are usually produced by growing the virus in chicken
eggs. Around three billion doses will be produced annually, with
delivery from November 2009.
[1][2]
In studies, the vaccine appears both effective and safe,
[3][4][5][6][7][8][9][10] providing a strong protective immune response and having similar safety profile to the normal seasonal influenza vaccine.
[11]
However, about 30% of people already have some immunity to the virus,
with the vaccine conferring greatest benefit on young people, since many
older people are already immune through exposure to similar viruses in
the past.
[12] The vaccine also provides some cross-protection against the
1918 flu pandemic strain.
[13]
Early results (pre-25 December 2009) from an observational cohort of
248,000 individuals in Scotland have shown the vaccine to be effective
at preventing H1N1 influenza (95.0% effectiveness [95% confidence
intervals (CI) 76.0–100.0]) and influenza related hospital admissions
(64.7% [95%CI 12.0–85.8]).
[14]
Developing, testing, and manufacturing sufficient quantities of a
vaccine is a process that takes many months. According to Keiji Fukuda
of the
World Health Organization
(WHO), "There's much greater vaccine capacity than there was a few
years ago, but there is not enough vaccine capacity to instantly make
vaccines for the entire world's population for influenza."
[15] Nasal mist version of the vaccine started shipping on 1 October 2009.
[16]
Types of vaccine
Two types of influenza vaccines are available:
TIV works by putting into the bloodstream those parts of three
strains of flu virus that the body uses to create antibodies; while LAIV
works by inoculating the body with those same three strains, but in a
modified form that cannot cause illness.
LAIV is not recommended for individuals under age 2 or over age 49,
[17] but might be comparatively more effective among children over age two.
[18]
Manufacturing methods
For the inactivated vaccines, the virus is grown by injecting it, along with some
antibiotics, into fertilized chicken eggs. About one to two eggs are needed to make each dose of vaccine.
[19] The virus replicates within the
allantois of the embryo, which is the equivalent of the
placenta in mammals. The fluid in this structure is removed and the virus purified from this fluid by methods such as
filtration or
centrifugation.
The purified viruses are then inactivated ("killed") with a small
amount of a disinfectant. The inactivated virus is treated with
detergent to break up the virus into particles, and the broken capsule
segments and released proteins are concentrated by centrifugation. The
final preparation is suspended in sterile
phosphate buffered saline ready for injection.
[20]
This vaccine mainly contains the killed virus but might also contain
tiny amounts of egg protein and the antibiotics, disinfectant and
detergent used in the manufacturing process. In multi-dose versions of
the vaccine, the preservative
thimerosal is added to prevent growth of bacteria. In some versions of the vaccine used in Europe and Canada, such as
Arepanrix and
Fluad, an
adjuvant is also added, this contains a fish oil called
squalene,
vitamin E and an
emulsifier called
polysorbate 80.
[21]
For the live vaccine, the virus is first adapted to grow at
25 °C (77 °F)
and then grown at this temperature until it loses the ability to cause
illness in humans, which would require the virus to grow at our normal
body temperature of
37 °C (99 °F).
Multiple mutations are needed for the virus to grow at cold
temperatures, so this process is effectively irreversible and once the
virus has lost
virulence (become "attenuated"), it will not regain the ability to infect people.
[22]
To make the vaccine, the attenuated virus is grown in chicken eggs as
before. The virus-containing fluid is harvested and the virus purified
by filtration; this step also removes any contaminating bacteria. The
filtered preparation is then diluted into a solution that stabilizes the
virus. This solution contains
monosodium glutamate,
potassium phosphate,
gelatin, the antibiotic
gentamicin, and sugar.
[23]
A new method of producing influenza virus is used to produce the
Novartis vaccine
Optaflu. In this vaccine the virus is grown in
cell culture instead of in eggs.
[24]
This method is faster than the classic egg-based system and produces a
purer final product. Importantly, there are no traces of egg proteins in
the final product, so the vaccine is safe for people with egg
allergies.
[25][26]
Previous seasonal vaccine production
The WHO recommended before the H1N1/09 outbreak
[27] that vaccines for the Northern Hemisphere's 2009–2010 flu season contain an
A(H1N1)-like virus, and stocks have been made.
[28][29] However, the strain of H1N1 in the
seasonal flu vaccine is different from the new pandemic strain H1N1/09 and offers no immunity against it.
[30] The US
Centers for Disease Control and Prevention (CDC) characterized over 80 new H1N1 viruses that may be used in a vaccine.
[31]
Production questions and decisions
Questions
There was concern in mid-2009 that, should a second, deadlier wave of
this new H1N1 strain appear during the northern autumn of 2009,
producing pandemic vaccines ahead of time could turn out to be a serious
waste of resources as the vaccine might not be effective against it,
and there would also be a shortage of seasonal flu vaccine available if
production facilities were switched to the new vaccine.
[15] Seasonal flu vaccine was being made as of May 2009, according to
WebMD.
The news site added that although vaccine makers would be ready to
switch to making a swine flu vaccine, many questions remained
unanswered, including: "Should we really make a swine flu vaccine?
Should we base a vaccine on the current virus, since flu viruses change
rapidly? Vaccine against the current virus might be far less effective
against a changed virus – should we wait to see if the virus changes? If
vaccine production doesn't start soon, swine flu vaccine won't be ready
when it's needed."
[32]
The costs of producing a vaccine also became an issue, with some U.S.
lawmakers questioning whether a new vaccine was worth the unknown
benefits. Representatives
Phil Gingrey and
Paul Broun,
for instance, were not convinced that the U.S. should spend up to US$2
billion to produce one, with Gingrey stating "We can't let all of our
spending and our reaction be media-driven in responding to a panic so
that we don't get Katrina-ed. ... It's important because what we are
talking about as we discuss the appropriateness of spending $2 billion
to produce a vaccine that may never be used – that is a very important
decision that our country has to make."
[33] In fact, a
Fairleigh Dickinson University PublicMind poll found in October 2009 that a majority (62%) of New Jerseyans were not planning on getting the vaccine at all.
[34]
Before the pandemic was declared, the WHO said that if a pandemic was
declared it would attempt to make sure that a substantial amount of
vaccine was available for the benefit of developing countries. Vaccine
makers and countries with standing orders, such as the U.S. and a number
of European countries, would be asked, according to WHO officials, "to
share with developing countries from the moment the first batches are
ready if an H1N1 vaccine is made" for a pandemic strain.
[35]
The global body stated that it wanted companies to donate at least 10%
of their production or offer reduced prices for poor countries that
could otherwise be left without vaccines if there is a sudden surge in
demand.
[36]
Gennady Onishchenko,
Russia's chief doctor, said on 2 June 2009 that swine flu was not
aggressive enough to cause a worldwide pandemic, noting that the current
mortality rate of confirmed cases was 1.6% in Mexico and only 0.1% in
the United States. He stated at a press conference, "So far it is
unclear if we need to use vaccines against the flu because the virus
that is now circulating throughout Europe and North America does not
have a pandemic nature." In his opinion, a vaccine could be produced,
but said that preparing a vaccine now would be considered "practice,"
since the world would soon need a new vaccine against a new virus.
"What's 16,000 sick people? During any flu season, some 10,000 a day
become ill in Moscow alone," he said.
[37]
Production timelines
After a meeting with the WHO on 14 May 2009, pharmaceutical companies
said they were ready to begin making a swine flu vaccine. According to
news reports, the WHO's experts will present recommendations to WHO
Director-General Margaret Chan, who was expected to issue advice to
vaccine manufacturers and the Sixty-second World Health Assembly.
[38][39][40] WHO's
Keiji Fukuda
told reporters "These are enormously complicated questions, and they
are not something that anyone can make in a single meeting." Most flu
vaccine companies can not make both seasonal flu vaccine and pandemic
flu vaccine at the same time. Production takes months and it is
impossible to switch halfway through if health officials make a mistake.
If the swine flu mutates, scientists aren't sure how effective a
vaccine made now from the current strain will remain.
[40] Rather than wait on the WHO decision, however, some countries in Europe have decided to go ahead with early vaccine orders.
[41]
On 20 May 2009, AP reported: "Manufacturers won't be able to start
making the [swine flu] vaccine until mid-July at the earliest, weeks
later than previous predictions, according to an expert panel convened
by WHO. It will then take months to produce the vaccine in large
quantities. The swine flu virus is not growing very fast in
laboratories, making it difficult for scientists to get the key
ingredient they need for a vaccine, the 'seed stock' from the virus
[...] In any case, mass producing a pandemic vaccine would be a gamble,
as it would take away manufacturing capacity for the seasonal flu
vaccine for the flu that kills up to 500,000 people each year. Some
experts have wondered whether the world really needs a vaccine for an
illness that so far appears mild."
[42]
Another option proposed by the CDC was an "earlier rollout of
seasonal vaccine," according to the CDC's Dr. Daniel Jernigan. He said
the CDC would work with vaccine manufacturers and experts to see if that
would be possible and desirable. Flu vaccination usually starts in
September in the United States and peaks in November. Some vaccine
experts agree it would be better to launch a second round of
vaccinations against the new H1N1 strain instead of trying to add it to
the seasonal flu vaccine or replacing one of its three components with
the new H1N1 virus.
[43]
The Australian company
CSL said that they were developing a vaccine for the swine flu and predicted that a suitable vaccine would be ready by August.
[44] However, John Sterling, Editor in Chief of
Genetic Engineering & Biotechnology News,
said on 2 June, "It can take five or six months to come up with an
entirely novel influenza vaccine. There is a great deal of hope that
biotech and pharma companies might be able to have something ready
sooner."
[45]
As of September 2009 a vaccine for
H1N1/09 was expected to be available starting in November 2009, with production of three billion doses per year.
[1][2]
It was expected that two doses would be needed to provide sufficient
protection, but tests indicated that one dose would be sufficient for
adults.
[46]
As of 28 September 2009
GlaxoSmithKline produced a vaccine made by growing the virus in hens' eggs, then breaking and deactivating the virus,
[47][48] and
Baxter International
produced a vaccine made in cell culture, suitable for those who have an
egg allergy. The vaccines have been approved for use in the
European Union.
[49][50][51][52][53][54][55]
Testing
Initial Phase I human testing began with
Novartis'
MF59 candidate in July 2009,
[56]
at which time phase II trials of CSL's candidate CSL425 vaccine were
planned to start in August 2009, but had not begun recruiting.
[57] Sanofi Pasteur's candidate inactivated H1N1 had several phase II trials planned as of 21 July 2009, but had not begun recruiting.
[58]
News coverage conflicted with this information, as Australian trials of
the CSL candidate were announced as having started on 21 July,
[59] and the Chinese government announced the start of trials of the Hualan Biological Engineering candidate.
[60]
Pandemrix, made by
GlaxoSmithKline (GSK), and
Focetria, made by
Novartis were approved by the
European Medicines Agency on 25 September 2009,
[49][50][51] and
Celvapan, made by Baxter was approved the following week.
[52][53][61] The first comparative clinical study of both vaccines started on children in the United Kingdom on 25 September 2009.
[citation needed] GSK announced results from clinical trials assessing the use of Pandemrix in children, adults, and the elderly.
[62][63][64][65] A 2009 trial examined the safety and efficacy of two different doses of the
split-virus vaccine, and was published in
The New England Journal of Medicine.
[66]
The vaccine used in the trail was prepared by CSL Biotherapies in
chicken eggs, in the same way as the seasonal vaccine. A robust immune
response was produced in over 90% of patients after a single dose of
either 15 or 30 μg of antigen. This study suggested that the current
recommendation for two doses of vaccine are overkill and that a single
dose is quite sufficient.
Arepanrix, an
AS03-
Adjuvanted
H1N1 Pandemic Influenza Vaccine similar to Pandemrix and also made by
GSK, was authorized by Canada's Minister of Health on 21 October 2009.
[67][68][69]
Adverse events
A review by the
U.S. National Institutes of Health (NIH) concluded that the 2009 H1N1 ("swine flu") vaccine has a safety profile similar to that of seasonal vaccine.
[11]
In an initial clinical trial in Australia, non-serious adverse events
were reported by about half of the 240 people vaccinated, with these
events including tenderness and pain at the site of injection, headache,
malaise, and muscle pain.
[66]
Two people had more severe events, with a much longer spell of nausea,
muscle pain and malaise that lasted several days. The authors stated
that the frequency and severity of these adverse events were similar to
those normally seen with seasonal influenza vaccines.
[66] A second trial involved 2,200 people ranging from 3 to 77 years of age.
[70]
In this study no patients reported serious adverse events, with the
most commonly observed events being pain at the injection site and
fever, which occurred in 10–25% of people.
[70]
Although this trial followed up patients individually, the Government
has been criticized for relying on voluntary reporting for
post-vaccination evaluation in other circumstances, since this is
"unlikely to accurately measure the percentage of people who get adverse
effect".
[12]
As of 19 November 2009, the World Health Organization (WHO) said that
65 million doses of vaccine had been administered and that it had a
similar safety profile to the seasonal flu vaccine, with no significant
differences in the adverse events produced by the different types of
vaccine.
[71]
There has been one report of an adverse event per 10,000 doses of
vaccine, with only five percent of these adverse events being serious,
an overall rate of serious events of one in 200,000 doses.
[71]
In Canada, after 6.6 million doses of vaccine had been distributed
between 21 October and 7 November, there were reports of mild adverse
events in 598 people vaccinated including: nausea, dizziness, headache,
fever, vomiting, and swelling or soreness at the injection site. There
were reports of tingling lips or tongue, difficulty breathing, hives,
and skin rashes. Thirty six people had serious adverse events, including
anaphylaxis
and febrile convulsions. The rate of serious adverse events is one in
200,000 doses distributed, which according to Canada's chief public
health officer, is less than expected for the seasonal flu vaccine.
GlaxoSmithKline recalled a batch of vaccine in Canada after it appeared
to cause higher rates of adverse events than other batches.
[72]
In the USA 46 million doses had been distributed as of 20 November 2009
and 3182 adverse events were reported. The CDC stated that the "vast
majority" were mild, with about one serious adverse event in 260,000
doses.
[73]
In Japan around 15 million people had been vaccinated by 31 December
2009. 1,900 cases of side effects and 104 cases of death were reported
from medical institutions. The health ministry announced that it will
conduct epidemiologic investigation.
[74]
In France, around five million people had been vaccinated by 30
December 2009. 2,657 cases of side effects, eight cases of intrauterine
death and five cases of miscarriages were reported after vaccination by
afssaps.
[75]
Rare potential adverse events are temporary bleeding disorders and
Guillain-Barré syndrome (GBS), a serious condition involving the
peripheral nervous system,
from which most patients recovery fully within a few months to a year.
Some studies have indicated that influenza-like illness is itself
associated with an increased risk of GBS, suggesting that vaccination
might indirectly protect against the disorder by protecting against flu.
[61]
According to Marie-Paule Kieny of WHO assessing the side-effects of
large-scale influenza vaccination is complicated by the fact that in any
large population a few people will become ill and die at any time.
[71]
For example in any six-week period in the UK six sudden deaths from
unknown causes and 22 cases of Guillain-Barré syndrome would be
expected, so if everyone in the UK were vaccinated, this background rate
of illness and death would continue as normal and some people would die
simply by chance soon after the vaccination.
[76]
Some scientists have reported concerns about the longer-term effects
of the vaccine. For instance, Sucharit Bhakdi, professor of medical
microbiology at the Johannes Gutenberg University of Mainz in Germany,
wrote in the journal,
Medical Microbiology and Immunology, of the possibility that immune stimulation by vaccines or any other cause might worsen pre-existing heart disease.
[77][78]
Chris Shaw, a neuroscientist at the University of British Columbia,
expressed concern that serious side-effects may not appear immediately;
he said it took five to ten years to see most of the
Gulf War syndrome outcomes.
[77]
The CDC states that most studies on modern influenza vaccines have seen no link with GBS,
[79][79][80][81] Although one review gives an incidence of about one case per million vaccinations,
[79][82] a large study in China, reported in
The New England Journal of Medicine covering close to 100 million doses of H1N1 flu vaccine found only eleven cases of
Guillain-Barre syndrome,
[10] actually lower than the normal rate of the disease in China,
[10] and no other notable side effects.
[10]
Pregnant women and children
A 2009 review of the use of influenza vaccines in pregnant women
stated that influenza infections posed a major risk during pregnancy and
that multiple studies had shown that the inactivated vaccine was safe
in pregnant women, concluding that this vaccine "can be safely and
effectively administered during any trimester of pregnancy" and that
high levels of immunization would avert a "a significant number of
deaths".
[83]
A 2004 review of the safety of influenza vaccines in children stated
that the live vaccine had been shown to be safe but that it might
trigger wheezing in some children with asthma; less data for the
trivalent inactivated vaccine was available, but no serious symptoms had
been seen in clinical trials.
[84]
Squalene
Newsweek states that "wild rumours" about the swine flu
vaccine are being spread through e-mails, it writes that "The claims are
nearly pure bunk, with only trace amounts of fact."
[85] These rumours generally make unfounded claims that the vaccine is dangerous and they may also promote
conspiracy theories.
[85] For example,
Newsweek states that some chain e-mails make false claims about
squalene (shark liver oil) in vaccines.
The New York Times also notes that anti-vaccine groups have spread "dire warnings" about formulations of the vaccine that contain squalene as an
adjuvant.
[86]
An adjuvant is a substance that boosts the body's immune response,
thereby stretching the supply of the vaccine and helping immunize
elderly people with a weak immune system.
[72][87] Squalene is a normal part of the human body, made in the liver and circulating in the blood,
[88] and is also found in many foods, such as
eggs and
olive oil.
[89][90] None of the formulations of vaccine used in the US contain squalene, or any other adjuvant.
[89]
However, some European and Canadian formulations do contain 25 μg of
squalene per dose, which is roughly the amount found in a drop of olive
oil.
[21][91] Some animal experiments have suggested that squalene might be linked to autoimmune disorders.
[77][92] although others suggest squalene might protect people against cancer.
[93][94]
Squalene-based adjuvants have been used in European influenza
vaccines since 1997, with about 22 million doses administered over the
past twelve years.
[95]
The WHO states that no severe side effects have been associated with
these vaccines, although they can produce mild inflammation at the site
of injection.
[95]
The safety of squalene-containing influenza vaccines have also been
tested in two separate clinical trials, one with healthy non-elderly
people,
[96] and one with elderly people,
[87]
in both trials the vaccine was safe and well tolerated, with only weak
side-effects, such as mild pain at the injection site. A 2009
meta-analysis
brought together data from 64 clinical trials of influenza vaccines
with the squalene-containing adjuvant MF59 and compared them to the
effects of vaccines with no adjuvant. The analysis reported that the
adjuvanted vaccines were associated with slightly lower risks of chronic
diseases, but that neither type of vaccines altered the normal rate of
autoimmune diseases; the authors concluded that their data "supports the
good safety profile associated with MF59-adjuvanted influenza vaccines
and suggests there may be a clinical benefit over non-MF59-containing
vaccines".
[97]
A 2004 review of the effects of adjuvants on mice and humans concluded
that "despite numerous case reports on vaccination induced autoimmunity,
most epidemiological studies failed to confirm the association and the
risk appears to be extremely low or non-existent", although the authors
noted that the possibility that adjuvants might cause damaging immune
reactions in a few susceptible people has not been completely ruled out.
[98]
A 2009 review of oil-based adjuvants in influenza vaccines stated that
this type of adjuvant "neither stimulates antibodies against squalene
oil naturally produced by the humans body nor enhances titers of
preexisting antibodies to squalene" and that these formulations did not
raise any safety concerns.
[99]
A paper published in 2000 suggested that squalene might have caused of
Gulf War syndrome by producing anti-squalene antibodies,
[77][100] although other scientists stated that it was uncertain if the methods used were actually capable of detecting these antibodies.
[101]
A 2009 U.S. Department of Defense study comparing healthy Navy
personnel to those suffering from Gulf War syndrome was published in the
journal
Vaccine, this used a validated test for these antibodies
and found no link between the presence of the antibodies and illness,
with about half of both groups having these antibodies and no
correlation between symptoms and antibodies.
[102] Furthermore, none of the vaccines given to US troops during the Gulf war actually contained any squalene adjuvants.
[88][103]
Thiomersal
Multi-dose versions of the vaccine contain the preservative
thiomersal (also known as thimerosal), a
mercury compound that prevents contamination when the vial is used repeatedly.
[104] Single-dose versions and the live vaccine do not contain this preservative.
[104] In the U.S., one dose from a multi-dose vial contains approximately 25 micrograms of mercury, a bit less than a typical
tuna fish sandwich.
[105][106] In Canada, different variants contain five and 50 micrograms of thimerosal per dose.
[107] The use of thiomersal has been
controversial, with claims that it can cause
autism and other
developmental disorders.
[108] The U.S.
Institute of Medicine examined these claims and concluded in 2004 that the evidence did not support any link between vaccines and autism.
[109] Other reviews came to similar conclusions, with a 2006 review in the
Canadian Journal of Neurological Sciences stating that there is no convincing evidence to support the claim that thimerosal has a causal role in autism,
[110] and a 2009 review in the journal
Clinical Infectious Diseases stating that claims that mercury can cause autism are "biologically implausible".
[111] The U.K.
National Health Service stated in 2003 that "There is no evidence of long-term adverse effects due to the exposure levels of thiomersal in vaccines."
[112] The
World Health Organization concluded that there is "no evidence of toxicity in infants, children or adults exposed to thiomersal in vaccines".
[113]
Indeed, in 2008 a review noted that even though thiomersal was removed
from all US childhood vaccines in 2001, this has not changed the number
of autism diagnoses, which are still increasing.
[114]
Dystonia
According to the CDC, there is no evidence either for or against
dystonia
being caused by the vaccinations. Dystonia is extremely rare. Due to
the very low numbers of cases, dystonia is poorly-understood.
[115] There were only five cases noted that might have been associated with influenza vaccinations over a span of eighteen years.
[115]
In one recent case, a woman noted flu-like symptoms, followed by
difficulties with movement and speech starting ten days after a seasonal
influenza vaccination.
[116]
However the Dystonia Medical Research Foundation stated that it is
unlikely that the symptoms in this case were actually dystonia and
stated that there has "never been a validated case of dystonia resulting
from a flu shot".
[117]
Children vaccine recall
On 15 December 2009, One of the five manufacturers supplying the H1N1
vaccine to the United States recalled thousands of doses because they
were not as potent as expected. The French manufacturer
Sanofi Pasteur
voluntarily recalled about 800,000 doses of vaccine meant for children
between the ages of six months and 35 months. The company and the
Centers for Disease Control and Prevention
(CDC) emphasized that the recall was not prompted by safety concerns,
and that even though the vaccine is not quite as potent as it is
supposed to be, children who received it do not need to be immunized
again. The CDC emphasized that there is no danger for any child who
received the recalled vaccine. When asked what parents should do, CDC
spokesman Tom Skinner said, "absolutely nothing." He said if children
receive this vaccine, they will be fine.
[118][119]
Pandemrix-related increase of narcolepsy in Finland and Sweden
In 2010,
The Swedish Medical Products Agency (MPA) and
The Finnish National Institute for Health and Welfare (THL) received reports from Swedish and Finnish health care professionals regarding
narcolepsy as suspected adverse drug reaction following
Pandemrix flu vaccination. The reports concern children aged 12–16 years where symptoms compatible with
narcolepsy, diagnosed after thorough medical investigation, have occurred one to two months after vaccination.
THL concluded in February 2011 that there is a clear connection
between the Pandemrix vaccination campaign of 2009 and 2010 and
narcolepsy epidemic in Finland: there was a nine times higher
probability to get narcolepsy with vaccination than without it.
[120][121]
At the end of March 2011, an MPA press release stated: "Results from a
Swedish registry based cohort study indicate a 4-fold increased risk of
narcolepsy in children and adolescents below the age of 20 vaccinated
with Pandemrix, compared to children of the same age that were not
vaccinated."
[122] The same study found no increased risk in adults who were vaccinated with Pandemrix.
Availability
Centers for Disease Control and Prevention
The American
Centers for Disease Control and Prevention issued the following recommendations on who should be vaccinated (order is not in priority):
[123][124][125][126]
- Pregnant women, because they are at higher risk of complications and
can potentially provide protection to infants who cannot be vaccinated;
- Household contacts and caregivers for children younger than 6 months
of age, because younger infants are at higher risk of influenza-related
complications and cannot be vaccinated. Vaccination of those in close
contact with infants younger than 6 months old might help protect
infants by "cocooning" them from the virus;
- Healthcare and emergency medical services personnel, because
infections among healthcare workers have been reported and this can be a
potential source of infection for vulnerable patients. Also, increased
absenteeism in this population could reduce healthcare system capacity;
- All people from 6 months through 24 years of age:
- Children from 6 months through 18 years of age, because cases of
2009 H1N1 influenza have been seen in children who are in close contact
with each other in school and day care settings, which increases the
likelihood of disease spread, and
- Young adults 19 through 24 years of age, because many cases of 2009
H1N1 influenza have been seen in these healthy young adults and they
often live, work, and study in close proximity, and they are a
frequently mobile population; and,
- Persons aged 25 through 64 years who have health conditions associated with higher risk of medical complications from influenza.
- Once the demand for these groups has been met at a local level,
everyone from the ages of 25 through 64 years should be vaccinated too.
In addition, the CDC recommends
Children through 9 years of age should get two doses of vaccine,
about a month apart. Older children and adults need only one dose.[127][128]
National Health Service
The
UK's
National Health Service policy is to provide vaccine in this order of priority:
[129]
- People aged between six months and 65 years with:
- chronic lung disease;
- chronic heart disease;
- chronic kidney disease;
- chronic liver disease;
- chronic neurological disease;
- diabetes; or
- suppressed immune system, whether due to disease or treatment.
- All pregnant women.
- People who live with someone whose immune system is compromised (for example, people with cancer or HIV/AIDS).
- People aged 65 and over in the seasonal flu vaccine at-risk groups.
This excludes the large majority of individuals aged six months to 24 years, a group for which the CDC recommends vaccination.
The NHS notes that:
- Healthy people over 65 years of age seem to have some natural immunity.
- Children, while disproportionately affected, tend to make full recoveries.
- The vaccine is ineffective in young infants.
The United Kingdom began its administration program 21 October 2009.
UK Soldiers serving in Afghanistan will also be offered vaccination.
[130][131]
Surplus vaccine
By April 2010, it was apparent that most of the vaccine was not
needed. The US government had bought 229 million doses of H1N1 vaccines
of which 91 million doses were used; of the surplus, some of it was
stored in bulk, some of it was sent to developing countries and 71
million doses will be destroyed.
[132] The
World Health Organization is planning to examine if it overreacted to the H1N1 outbreak.
[132]
Political issues
General political issues, not restricted to the 2009 outbreak, arose
regarding the distribution of vaccine. In many countries supplies are
controlled by national or local governments, and the question of how the
vaccine will be allocated should there be an insufficient supply for
everyone is critical, and will likely depend on the patterns of any
pandemic, and the age groups most at risk for serious complications,
including death. In the case of a lethal pandemic people will be
demanding access to the vaccine and the major problem will be making it
available to those who need it.
[133]
While it has been suggested that
compulsory vaccination
may be needed to control a pandemic, many countries do not have a legal
framework that would allow this. The only populations easily compelled
to accept vaccination are military personnel (who can be given routine
vaccinations as part of their service obligations), health care
personnel (who can be required to be vaccinated to protect patients),
[citation needed]
and school children, who (under United States constitutional law) could
be required to be vaccinated as a condition of attending school.
[134]
In August 2010, the
Daily Mail
printed an article that stated that "a third of the experts advising
the World Health Organisation about the swine flu pandemic had ties to
drugs firms" and that of the 20 members of the Scientific Advisory Group
for Emergencies, which advised the British Government on swine flu, 11
had done work for the pharmaceutical industry or were linked to it
through their universities. A spokesman for the WHO is stated as having
"denied that the experts' work gave rise to a conflict of interest".
[135]
See also
