Information About Vaccines & Vaccine Myths
Pharmasave is dedicated to educating our customers to ensure you stay healthy. For more information about influenza, shingles, travel vaccines and vaccine myths, browse through this page or give us a call today. One of our knowledgeable staff members would be happy to answer any questions you may have.
Influenza is commonly referred to as the “flu” and is caused by the influenza A and/or B virus. Influenza A viruses are categorized into subtypes on the basis of two surface antigens: hemagglutinin and neuraminidase. Influenza B viruses separate into two distinct genetic lineages but are not categorized into subtypes. Immunity to one subtype does not confer protection against another subtype, and mutations occur often. Although influenza A is more common and tends to cause more severe illnesses, it is impossible to differentiate clinically between influenza A and B.
Influenza is normally seen between November and April in the northern hemisphere. Initial symptoms tend to be more systemic in nature (i.e. muscle pain, fever, headache, chills, fatigue), with respiratory symptoms (i.e. cough, sore throat, rhinitis) becoming more prominent as systemic symptoms subside. The infectivity period starts before the onset of symptoms and usually lasts 5-7 days, but shedding of the virus may continue for 7 days or longer after the start of symptomatic illness, especially in children and immunocompromised patients. Complications of influenza include pneumonia and even death. In 2011, influenza and pneumonia together were responsible for 5,767 deaths and ranked as the 8th leading cause of death in Canada.
The most effective way to prevent influenza is to get your annual influenza vaccination. Our pharmacists can help you prepare for the flu season by helping you stock your home medication cabinet with products to both prevent and treat the flu.
*Antiviral chemoprophylaxis is no longer recommended other than in select circumstances, such as for control of outbreaks in long-term care facilities.
Shingles are caused by the Varicella-Zoster Virus which is the same virus that causes the chickenpox. The Varicella-Zoster Virus resides in the nerve roots; however it can become active many years after you had the chickenpox. The majority of people who become afflicted with shingles are between 50 to 70 years of age, but it can happen at any age.
Shingles often occurs when your immune system is depressed for any number of reasons:
- Older age
- Immunosuppressant medications
- Radiation treatment
- HIV infection
- Some cancers
The most common signs and symptoms associated with shingles are a red rash that follows a dermatome pattern, upset stomach, fever and chills. These symptoms are typically preceded by sensitivity, itch, numbness and localized pain before the shingles rash appears. After a few days, the rash becomes painful to touch and vesicles appear as fluid-filled blisters. The most common sites for the rash include the chest, abdomen, back, buttocks, neck and sometimes the face and scalp. The fluid-filled blisters will break, which can cause the shingles virus to spread from one person to another. Only after the blisters have dried out and crusted over is the person no longer contagious.
There are cases where pain can last for up to 3 months or longer in a small percentage of people. This pain is commonly referred to as Post-Herpetic Neuralgia (PHN) and is characterized by severe pain along affected nerves where the Herpes Zoster virus is located and can last for months. In some rare cases, PHN can be permanent.
Shingles can lead to a few serious complications, such as when the Varicella virus affects the eyes. If you suspect shingles in the eye, immediately seek medical attention. Shingles can also travel to the face which can result in a condition called Ramsay Hunt Syndrome.
Antiviral medications such as acyclovir, valcyclovir and famciclovir can be initiated within 72 hours of developing shingles. Antiviral medications can help reduce the risk of developing neuralgic pain associated with shingles. To relieve the itching and pain associated with shingles, you can try using cool, moist compressions, antihistamines, calamine lotion and soaking in a cool bath with oatmeal.
Shingles prevention starts with getting vaccinated against the chickenpox and shingles. Zostavax is the shingles vaccine which is approved for people older than 50 years of age and has been shown to reduce both the intensity and duration of the pain caused by shingles.
If you are travelling outside of Canada, it is important that you and your family get vaccinated appropriately before you leave. Depending on the country you are visiting, the vaccines required and/or recommended will vary. The most commonly recommended travel vaccines include but are not limited to the following:
- Hepatitis A and B
- Typhoid Fever
- Japanese Encephalitis
- Yellow Fever
- Meningococcal Meningitis
For more information on travel vaccines, visit www.immunizebc.ca.
Dispelling Vaccine Myths and Misconceptions
Vaccines are one of the greatest achievements in medical history, as they have nearly eradicated communicable diseases. The World Health Organization estimates that yearly immunizations save 2 to 3 million people on average per year from vaccine-preventable diseases such as polio, diphtheria, mumps, measles and influenza, to name just a few1.
Sadly, communicable diseases are on the rise in North America and globally, which has been attributed to a decrease in vaccination rates. This statistic underscores the dire need for a robust vaccination program. As a medical provider, it is crucial that we educate our patients about the growing anti-vaccine movement and misconceptions which have been portrayed about immunizations in the media. The most common concerns and misconceptions that people have about immunizations are described below.
Myth: DTP Vaccines Cause Encephalitis
One of the biggest fears of parents is that immunizations can cause autism and other neurodevelopmental disorders2. It was believed that the DTP vaccine could cause irreversible neurodevelopmental disorders. However, back in 1991 the whole-cell pertussis vaccine was replaced with an acellular pertussis vaccine (DTap) which has shown no evidence of a link between encephalopathy and DTap 3.
Myth: MMR Vaccines Cause Autism
The Wakefield study hypothesized that the MMR vaccine could cause a reaction in the gut, leading to the release of brain-damaging peptides which could increase the risk of developing autism. This study resulted in almost mass hysteria that vaccines cause autism. The report was deeply flawed in study design, and ten of the thirteen co-authors of the study have fully retracted their support for the MMR-autism hypothesis to date. Even Wakefield himself states in his paper that his study did not prove that the MMR vaccine could be established as a direct cause of ASD4. Twenty studies have explored and subsequently refuted the theory that the MMR vaccine was a cause of ASD.
Myth: Thimerosal is Toxic to the Central Nervous System
Thimerosal is a preservative which is used to inhibit both the growth of bacteria and fungi in multi-dose vaccine preparations. In 2001, thimerosal was removed from nearly all vaccines on the market because of fears about mercury toxicity that could potentially occur in a child receiving multiple vaccinations in their first 6 months of life5. The concern regarding thimerosal’s potential to cause toxicity to the nervous system was unwarranted. Thimerosal breaks down into ethylmercury, is less toxic the methylmercury found in fish, and is rapidly excreted from the body. It has also been shown to not cause disease or ASD6.
Myth: Multiple Vaccinations Overwhelm Infants’ Immune Systems
The infant’s immune system is capable of responding to multiple viruses and bacteria on a daily basis. The goal of vaccines are to stimulate the body’s B cells which secrete antibodies, and prime the immune system to protect itself from the more virulent, wild form of the disease7. Each vaccine contains a precise amount of antigens to which our body responds to. The immune challenges from vaccines are significantly lower than that from bacteria and viruses which we encounter on a daily basis, making it highly unlikely that the immune system is overwhelmed by vaccines. Hence, infants can theoretically handle upwards of 10,000 vaccines in a single day8!
Myth: Adjuvant Ingredients in Vaccines are Unsafe
Aluminum and formaldehyde are two adjuvants found in vaccines. Aluminum is used to induce a stronger immune response, and is naturally found in our environment. Studies have shown that the addition of a small amount of aluminum in the body is not harmful9. Unless a person has a serious kidney disease, aluminum is unlikely to build up in significant concentrations to cause any disease10. Formaldehyde is used in vaccines to inactivate viruses such as polio and hepatitis A, as well as toxins such as diphtheria and tetanus11. The amount of formaldehyde found in vaccines after processing is only trace amounts, which is not enough to cause disease.
Overwhelming evidence provides support for both safety and effectiveness of vaccines in reducing the incidence of communicable disease. Like any other medication, vaccines carry some risk, but the benefits outweigh the risk.
1. World Health Organization Immunization Statistics. http://www.who.int/mediacentre/en/
2. Dempsey AF., Schaffer S., Singer D., et al. Alternative vaccination schedule preferences among parents of young children. Pediatrics 2011;128(5): 848-856.
3. Pertussis vaccination: use of acellular pertussis vaccine among infants and young children. Recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Recomm Rep 1997;46(RR-7):1-25.
4. Gerber JS., Offit PA. Vaccines and autism: a tale of shifting hypotheses. Clin Infect Dis 2009;48(4):456-461.
5. Centers for Disease Control and Prevention. Timeline: thimerosal in vaccines. http://www.cdc.gov/vaccinesafety/concerns/thimerosal/timeline.html
6. Hurley AM., Tadrous M., Miller ES. Thimerosal-containing vaccines and autism: a review of recent epidemiologic studies. J Pediatr Pharmacol Ther 2010;15(3):173-181.
7. Centers for Disease Control and Prevention. Frequently asked questions about multiple vaccines and the immune system. http://www.cdc.gov/vaccinesafety/concerns/multiple-vaccines-immunity.html
8. Offit PA., Quarles J., Gerber MA., et al. Addressing parents’ concerns: do multiple vaccines overwhelm or weaken the infant’s immune system? Pediatrics 2002;109(1):124-129.
9. Food and Drug Administration. Study reports aluminum in vaccines pose extremely low risk to infants. http://www.chop.edu/centers-programs/vaccine-education-center
10. Offit PA., Jew RK. Addressing parents’ concerns: do vaccines contain harmful preservatives, adjuvants, additives, or residuals? Pediatrics 2003;112(6Pt1):1394-1397.
11. Food and Drug Administration. FDA study reinforces no safety concern from residual formaldehyde in some infant vaccines. http://www.fda.gov/