The Importance of Immunizations

Immunizations are a way to protect us from getting diseases. Because infants and young children are the principal recipients of most vaccines developed during the twentieth century, a common misperception is that vaccinations are solely for the young. On the contrary, vaccinations are recommended for people of all ages.

Improved vaccination coverage can result in additional reductions in the incidence of many preventable diseases and decrease associated morbidity and mortality.

Through vaccination programs many vaccine-preventable diseases have been eliminated and the incidence of several others reduced. For example, Polio is a highly infectious disease caused by a virus that invades the nervous system, and can cause total paralysis in a matter of hours. Among those paralyzed, 5-10% die when their breathing muscles are immobilized. Since the Global Polio Eradication Initiative was launched in 1988, the number of cases has fallen by over 99%. In 2012, only three countries in the world remain polio-endemic. With continued effort, there is hope that in a few years polio will be eradicated completely.

Another example of success is the HPV vaccine. In 2009, an estimated 4,070 deaths in the United States resulted from infection due to HPV strains. Causing the majority of cervical cancers, this disease is preventable with HPV vaccine and routine Pap smear testing. Therefore, a routine 3-dose HPV vaccine is recommended for all females to help prevent not only cervical, but also vaginal, vulvar and anal cancer. This very important HPV vaccine is now available in Shanghai United Family Hospital: HPV 2 for women 9-45 years old, HPV 4 for 20-45 years old and HPV 9 for 16-26 years old.

Moreover, there are also the travel specific vaccines depending on the area you are going such as for yellow fever, typhoid, Japanese encephalitis, or rabies.

Immunization schedules differ from country to country but are generally similar. Since we live in China we need to follow the recommendations of local public health authorities:

Japanese encephalitis: is a viral infection with low incidence but high impact (30% mortality):

JE vaccine: recommended for children and adults above 6 month old

Measles: In China because a large number of children get measles before the age of 1 year old, CDC recommends one of the following three:

• Measles vaccine: at 8 months or older, or
• Measles and rubella: at 8 months or older and
• MMR vaccine: first MMR is given at 18 month, second at 4 years of age.

Other recommended vaccines:

• BCG: for infants (prevents aggressive forms of tuberculosis)
• Diphtheria: DTaP (Diphtheria, Tetanus and Pertussis) vaccine is routinely recommended for infants and children at ages 2 months, 4 months, 6 months, 18 months, and 4 through 6 years. Booster doses are required beginning at age 11 years.

• Tetanus: people of all ages need tetanus vaccine boosters every 10 years all life

• Pertussis: prevents the extremely transmissible whooping cough
• Haemophilus: is the cause of meningitis, pneumonia, septic arthritis; immunization in early childhood led to a significant reduction of those infections.
• Pneumococcal 13: from 6 weeks to 6 month of age

• Meningococcal A+C vaccine: at 6 months and 9 months;
• Meningococcal ACWY: 2 years old and above

• Rota: 2-6 month of age
• Hepatitis A: at 18 month, booster 6 month later
• Hepatitis B: at birth, second dose at 1-2 month, third dose at 6-18 month; prevents hepatitis B, cirrhosis and liver cancer
• Rabies: dogs in most parts of the world are not vaccinated, and rabies is 100% fatal.
• Varicella: above 1 year old; second dose at 4 years old
• Herpes zoster: for adults 50 years of age and older

Influenza: the annual seasonal influenza vaccination is recommended for everyone over the age of 6 months who have no contraindications.

Shanghai United family Hospital started vaccination for Flu: Trivalent for children >= 6 months  to 3 years old ( two doses one month apart regardless of previous vaccination completion history); and Quardrivalent for adult and children >= 3 years old (one dose only)

Modern vaccines are safe and effective; however, adverse events have been reported after administration of all vaccines. An adverse reaction is an undesirable side effect that occurs after a vaccination. These reactions are classified as local, systemic, or allergic. Local reactions (e.g., redness) are usually the least severe and most frequent. Systemic reactions (e.g., fever) occur less frequently than local reactions, and severe allergic reactions (e.g., anaphylaxis) are the least frequent. Severe adverse reactions are rare.

The most common allergen in vaccines is egg protein, which is found in both influenza and yellow fever vaccines. Ordinarily, people who are able to safely eat eggs or egg products can receive these vaccines; those who have had an anaphylactic or anaphylactic-like allergy to eggs or egg proteins should not receive these vaccines.

If a patient has a moderate or severe illness, the vaccination should be postponed. Conversely, vaccinations need not be delayed due to the presence of a mild respiratory tract illness or other acute illness. The only contraindication applicable to all vaccines is a history of a severe allergic reaction (i.e., anaphylaxis) resulting from a previous vaccine dose or component, unless the recipient has since been desensitized. Women known to be pregnant and severely immunocompromised patients generally should also not receive live vaccines.

As always, please keep your vaccination records up to date and consult with your physician should you have any questions or concerns.

References:

“General Recommendations on Immunization Recommendations of the Advisory Committee on Immunization Practices (ACIP).” MMWR Recommendations and Reports. Volume 60, Number 2. January 28, 2011.

www.cdc.gov/vaccines

www.immunize.org

www.who.int/mediacentre/factsheets/fs114/en/