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The aim of this article is to supply credible information published about the 2009 H1N1 flu vaccine. It is not intended in anyway to encourage or discourage readers from taking the vaccine.The majority of individuals who contracted the 2009 H1N1 flu experienced a mild illness compared to a small number who suffered severe illness.
Even if the current pandemic continues to be a mild illness, WHO is still monitoring the situation fearing that a possible second wave might be more difficult as larger numbers of people become infected. Fears are mainly due to the supposed increased burden on health services that would disrupt intensive care units and other hospital care offered to patients with different diseases. To prepare for this, the race for vaccine manufacturing is still ongoing.
However, the safety of the 2009 H1N1 flu vaccine has been questionable, particularly due to the short time that was allocated to perform clinical trials. Guillain-Barré syndrome, the use of thimerosal, and the presence of adjuvants are three main speculations currently being raised against the current H1N1 vaccine.
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What is the 2009 H1N1 flu?
In March 2009, an outbreak of H1N1 influenza A virus infection was detected in Mexico, with
subsequent cases spreading worldwide. In June 2009, the World Health Organization raised its
pandemic alert level to phase 6, indicating widespread transmission. The 2009 flu pandemic was found to
be caused by a novel virus made of genes from four origins: two different swine strains (North American and Eurasian swine strains), one human strain, and one avian strain of influenza. Scientists call this a quadruple re-assortment.
In KSA, a royal decree was announced postponing the school two weeks in order to allow enough time to educate teachers about the current H1N1 flu and to protect children from contracting the flu.
What does the CDC say about the safety of the 2009 H1N1 vaccine?
The CDC believes that the benefits of the 2009 H1N1 influenza vaccine will be much greater than the risks associated with H1N1 flu infection.
According to CDC, vaccination is the best method to protect against the 2009 H1N1 flu and its complications.
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What does the WHO say about the safety of the 2009 H1N1 vaccine?
According to the World Health Organization, regulatory authorities in countries producing the vaccine are carefully examining the risks prior to vaccine licensing. Outcomes of trials completed so far suggest that the 2009 H1N1 vaccines are as safe as seasonal influenza vaccines.
Side effects are expected to be similar to those observed with seasonal influenza vaccines. Such side effects may include local reactions at the injection site and possibly fever, headache, muscle or joint pain. It is expected that these symptoms will be mild and short lasted.
However, even very large clinical trials will not be able to identify possible rare events that can occur when vaccines are administered to many millions of people.
The WHO advises all countries administering the new vaccine to conduct serious control measures for safety and to report any adverse reactions.
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Will the H1N1 flu vaccination program be compulsory or voluntary in the USA?
The vaccination program for H1N1 flu will be voluntary in the USA. Health officials are recommending that people get vaccinated in order to protect themselves from the 2009 H1N1 flu. People with health conditions such as asthma or diabetes, health care workers, pregnant women, children and young adults are particularly encouraged to take the vaccine. However, the final decision depends on each individual.
What is Guillain-Barré Syndrome?
Guillain-Barré Syndrome (GBS) is a rare neurological disorder where auto-antibodies against the nerve cells are produced resulting in muscle weakness and in some cases paralysis. Some people can recover from GBS, but some others have irreversible nerve damage. In rare cases, GBS can result in death caused by breathing problems.
What is the cause of Guillain-Barré Syndrome?
The exact cause of GBS remains unknown. It is suspected that stimulation of the body’s immune system may play a role in the development of GBS. Some people develop GBS after contracting an infectious disease. On rare occasions, individuals may develop GBS after receiving a vaccination.
Patients with a history of GBS have a greater likelihood of developing GBS than those without. It is being recommended that patients with a history of GBS and who are at low risk for severe influenza complications do not take the current pandemic flu vaccine.
What happened in 1976 during the swine flu vaccination program?
In 1976, millions of individuals in the United States were immunized against a swine flu, but the program was discontinued because of an increased incidence of Guillain-Barré syndrome (GBS) amongst those who received the vaccine. Until today, the link between GBS syndrome and the 1976 flu vaccine has not been clarified. Therefore, iIn order to detect a similar risk from the current H1N1 vaccination, hundreds of thousands of individuals would need to be vaccinated.
Even though the 1976 swine flu virus and the 2009 H1N1 virus are different and so are the vaccines developed against each; risk of developing complications will always be there with any flu vaccination campaign.
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What is thimerosal?
Thimerosal is an organic compound that is 49% mercury (Hg) by weight; it is usually present in multi-dose vials of vaccine to prevent bacterial and fungal contamination once the vial is opened. The use of thimerosal in childhood vaccination has been linked to increased risk of development of autism.
Will the 2009 H1N1 flu vaccine contain the preservative thimerosal?
The 2009 H1N1 influenza vaccine is prepared in different forms. Some will come in multi-dose vials and will contain thimerosal as a preservative.
However, some 2009 H1N1 flu vaccines will be available in single-dose vials, which will not have thimerosal. Also, the live-attenuated vaccine, which is given through the nose, is produced in single-units and therefore will not contain thimerosal. |
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What is an adjuvant?
An adjuvant is a substance that is used to increase specific immune responses to vaccines. Adjuvant therefore can help to reduce the amount of vaccine needed for each individual. Adjuvant oils such as squalene (MF59) have been used in human vaccines. In the literature, several reports suggested an association of adjuvanted vaccines and various autoimmune diseases.
Why adjuvants are used in vaccine?
Adjuvants used in some flu vaccines have the potential to boost the effectiveness of the vaccine and therefore to substantially reduce dosage.
Will the 2009 H1N1 vaccines contain adjuvants?
In the USA, only unadjuvanted vaccines will be used. This includes both the 2009 H1N1 and seasonal influenza vaccines that will be available for children and adults. So, the CDC is insuring that vaccines free from adjuvant are given to people in the USA.
According to the CDC, 2009 H1N1 vaccines with adjuvants are still being examined to determine their safety. Currently, the CDC is not recommending the adjuvanted vaccine.
However, for the rest of the world it seems that vaccine companies are opting out for the use of adjuvanted vaccine in order to stretch the quantities of the available vaccine material.
In conclusion, it is highly recommended that individuals ask their medical doctors all the questions they need to know about the 2009 H1N1 influenza vaccine in order to help them decide whether they need to take the vaccine or not.
References:
Trifonov V, Khiabanian H, Rabadan RGeographic Dependence, Surveillance, and Origins of the 2009 Influenza A (H1N1) Virus. N Engl J Med. 2009;361(2):115-9.
Evans D., Cauchemez S., Hayden F.G. "Prepandemic" immunization for novel influenza viruses, "swine flu" vaccine, guillain-barré syndrome, and the detection of rare severe adverse events. J Infect Dis 2009; 200 (3):321-8.
Morens D.M., Taubenberger J.K., Fauci A.S.The persistent legacy of the 1918 influenza virus. N Engl J Med. 2009; 361(3):225-9.
http://www.who.int/csr/disease/swineflu/notes/pandemic_influenza_vaccines_20090924/en/index.html
http://www.cdc.gov/h1n1flu/vaccination/thimerosal_qa.htm
http://www.cdc.gov/h1n1flu/vaccination/gbs_qa.htm
http://www.cdc.gov/h1n1flu/vaccination/vaccine_safety_qa.htm
http://www.who.int/csr/disease/swineflu/notes/h1n1_second_wave_20090828/en/index.html
http://www.cbc.ca/health/story/2009/09/03/swine-flu-vaccine.html
http://news.bbc.co.uk/2/hi/8274374.stm
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