What about Adverse Effects Following Immunisation (AEFI)?
Vaccines are manufactured to meet the most stringent and highest standards of safety. Before vaccines are licensed, the National Regulatory Authorities(NRA) requires many years of research, clinical trials and testing to ensure safety. This process may take 10-15 years or longer.
However, like any medication, vaccines may cause side effects. Once a vaccine is licensed for use, the NRA continually monitors its Adverse Effects Following Immunisations(AEFI). Any hint of a health problem which may or may not be directly related to a vaccine prompts further investigations by the NRA.
If an AEFI is found to be directly related to a vaccine, the NRA will initiate appropriate action, such as changing of vaccine labels or packaging, distributing safety alerts, inspecting manufacturers’ facilities and records, withdrawing recommendations for the use of the vaccine, or revoking the vaccine’s license.
Every individual is unique and may react differently to vaccinations. In most cases, vaccines are effective in protecting the person from disease and cause no side effects.
A few may experience mild AEFI eg soreness, swelling or redness at the injection site, low grade fever or slight malaise. In extremely rare circumstances, people may experience more serious side effects, like allergic reactions. These reactions are so rare that the risk is very difficult to quantify.
If your child develops a reaction to a vaccine, immediately call your doctor. If the reaction is severe, take your child to your doctor or emergency department immediately. Tell the attending doctor what happened, when it happened, and when the vaccination was given.
“Every individual is unique and may react differently to vaccinations. In most cases, vaccines are effective in protecting the person from disease and cause no side effects.”
In recent years, a number of web sites providing unbalanced, misleading and alarming vaccine safety information were established, raising undue fears among parents and patients. Myths and misinformation about vaccine safety can confuse parents who are trying to make sound decisions about their children’s healthcare.
Misinformation is rife on the Internet, making it hard to find reliable sources of information. In 2003, the United Nations Children’s Fund (UNICEF), WHO and keys NGOs initiated the Vaccine Safety Net Project (VSN) to respond promptly, efficiently, and scientifically to vaccine safety issues of potential global importance. A list of reliable websites on vaccines in 10 different languages can be found on the website: www.who.int/vaccine_safety/initiative/communication/network/vaccine_safety_websites/en/
“Misinformation is rife on the Internet, making it hard to find reliable sources of information.”
Vaccination is a very common and memorable milestone in a child’s life. As such, all adverse effects are quickly linked to the vaccine as being the cause. While a few sicknesses or reactions that follow vaccination may be caused by the vaccine, many are unrelated events that occur by chance or coincidence.
|Vaccine||Risk of AEFI|
|Hepatitis B||Anaphylaxis: 1 per 1,100,000 doses|
|Polio||Paralysis:1 per 2,500,000 doses of OPV (Oral Polio Vaccine). This risk is not present with Injectable Polio Vaccine (IPV)|
|BCG (Bacillus Calmette-Guerin), tuberculosis vaccine||
|Diphtheria,Tetanus, and Pertussis (DTaP)||
|Haemophilus influenzae type b (Hib)||No significant AEFI|
|Pneumococcus (PCV, pneumococcal conjugate vaccine)||No significant AEFI|
|Rotavirus||Intussusception (a type of gut obstruction): 1 per 20,000-100,000 doses|
|Measles, Mumps, and Rubella (MMR)||
|Typhoid||No significant AEFI|
|Hepatitis A||No significant AEFI|
|Varicella (chickenpox)||Mild varicella rash: 1 per 25-50 doses|
|Human Papilloma Virus (HPV)||Fainting can occur in teenagers after vaccine administration. It is recommended to observe 15 minutes in the clinic after HPV vaccine administration.|
|Risks caused by diseases|
|Hepatitis B||Chronic hepatitis in 90% of babies born to mothers with active hepatitis B infection Cancer of the liver in 40-50% of people with chronic hepatitis|
|Polio||Chronic hepatitis in 90% of babies born to mothers with active hepatitis B infection Cancer of the liver in 40-50% of people with chronic hepatitis|
|Tuberculosis||Meningitis (inflammation of the tissue covering the brain) in 13% of children with TB infecting organs outside the lungs, and 5% in those with TB affecting the entire lungs)|
|Diphtheria||Airway obstruction with 5-12% risk of deathInflammation of heart (myocarditis)Inflammation of nerves (neuritis)|
|Tetanus||Risk of death in 25% of infants with intensive care, muchhigher without intensive care|
|Pertussis||Encephalopathy (disease of brain), Fits, PneumoniaDeath: 2 in 1,000.|
|influenzae type b||Meningitis, Deafness|
|Pneumococcus||Most common cause of meningitis, pneumonia and otitis media in children. Risk of death from meningitis is 30% even in developed countries|
|Influenza||Often complicated by secondary bacterial infection
Risk of death: 1 per 1,000-2,000 cases in developed countries
|Measles||Mortality rate: 2-3 per 1,000 cases in developed countries, 10-20 fold in developing countriesRisk of encephalitis (inflammation of the brain): 1 per 1,000 cases in developed countriesRisk of subacute sclerosing panencephalitis (SSPE, a degenerative and fatal neurologic disorder): 4-11 per 100,000 cases|
|Mumps||Deafness, viral encephalitisRisk of orchitis (inflammation of the testis): 17-38%, mayresult in sub-fertilityMay cause miscarriages in girls|
|Rubella||Risk of congenital rubella syndrome (characterised by abnormalities affecting multiple organs) in fetus if a pregnant woman is infected during pregnancy (85% in the first trimester, 25-50% in the second trimester)|
|Typhoid||Risk of death: 35% in severe typhoid fever|
|Hepatitis A||Hepatitis with risk of liver failureDeath: 1 per 300 cases|
|Varicella (chickenpox)||Chickenpox that can be complicated by secondary bacterial infection|
|Human Papilloma Virus(HPV)||Risk of cervical cancer, anal cancer, or oral (mouth) cancer with HPV infection|
Comparing the two tables enables us to understand that the likelihood of AEFI is generally very small, while the risks from vaccine-preventable diseases are serious and some deadly.
Let us make wise and well-informed decisions for our children with regards to vaccination.