vaccine overview support for this program is made possible by the aafp foundation through a grant...

Vaccine Overview

Support for this program is made possible by the AAFP Foundation through a grant from Pfizer Inc.

Vaccine Overview

Developed for AFMRD by

Gail Colby, M.D. and Wendy Biggs, M.D.

Midland Family Medicine Residency

2010

Ehab Molokhia, MD and Gerald Liu, MD

University of South Alabama Family Medicine Residency

Updated 2012

Vaccine Overview

Objectives• Medical knowledge

– Describe the differences in active, passive and herd immunity

– Explain the difference between a live-attenuated and an inactivated vaccine

– State 3 true contraindications to vaccines

• Interpersonal communication– Explain to parents or guardian the reasons

for immunization

Vaccine Overview

Objectives• Systems-based practice

– Utilize resources to find vaccine recommendations and schedules

– Access the Immunization Information System for your state

– Explain the content of Vaccine Information Sheets

– Discuss the purpose and limitations of the Vaccine Adverse Event Reporting System

Vaccine Overview

Mr. and Mrs. A have recently moved to your town, and are now new patients. They bring their 4-month-old girl, 3-year-old and 5-year-old boys to you for well-child exams. The oldest children have no health issues. The baby, born by C-section, initially had some respiratory problems, but has been healthy since hospital discharge at day 4 of life.

Case

Vaccine Overview

When you inquire about immunizations, Mrs. A states “Well, the two oldest children were immunized. I’m too worried about the baby, so she has not had any shots. No one gets those diseases anymore, so I didn’t think she needed them any way.”

Case

What do you tell Mrs. A about why we vaccinate?

Vaccine Overview

Why Do We Vaccinate?• Prevent disease from occurring• Reduce morbidity and mortality if

disease acquired

Vaccine Overview

Do Vaccines Work?• Disease incidence declined rapidly after

vaccine available for that disease• Current U.S. sources of vaccine

preventable illnesses are:– Foreign born people living in the U.S.– Unvaccinated U.S. citizens

Vaccine Overview

Do Vaccines Work?Measles Example

Photo from www.cdc.gov. Image in public domain.

Vaccine Overview

Do Vaccines Work?• During the 1970’s, the hospital in your

town had one floor (50 beds) dedicated to pediatric patients. In 1996, the unit was down-sized to 30 beds. In 2004, volume was so low, the inpatient pediatric unit was closed.

What happened?

Vaccine Overview

What Happened?• The Hemophilus influenza

type b vaccine

Vaccine Overview

Hemophilus influenza type b • Hemophilus influenza type b (Hib)

causes serious infections• Prior to vaccine

– 1:200 children <5 years developed invasive Hib disease

– Estimated 20,000 cases invasive Hib/year prior to vaccine

Vaccine Overview

Hemophilus influenza type b• Vaccine introduced 1988

• 85-92% reduction in Hib invasive disease

– Dramatic reduction

• 1987 – Incidence 41/100,000

• 2000 – Incidence 1.6/100,000

• 2004 – Incidence 0.14/100,000

Vaccine Overview

Hemophilus influenza type b

– HIB meningitis now rare

– Inpatient pediatric units’ decline in

admissions parallel decline in

invasive Hib

Vaccine Overview

What if We Don’t Vaccinate?• Pertussis (Whooping cough)

– 1974: Great Britain decreased vaccination– 1978: epidemic of >100,000 cases of pertussis

and 36 deaths

• Diphtheria– Newly Independent States (NIS) (former

Soviet Union)– 1989: 839 cases of diphtheria– 1994: >157,000 cases and 5000 deaths

Vaccine Overview

What if We Don’t Vaccinate?• The diseases are still around

– 2002: Measles epidemic in Italy– 2003: Adult dies in U.S. of diphtheria – 2008: Child dies of diphtheria in Great

Britain– June 2009 - January 2010: Over 1,500

cases of mumps in the U.S.

Vaccine Overview

What if We Don’t Vaccinate?• Herd immunity

keeps the diseases

in check

– What is herd immunity?

Vaccine Overview

Herd Immunity• Most of population immunized

• Disease itself still exists, but spread

prevented by lack of available hosts

• Unimmunized person less likely to

come in contact with infected person

Vaccine Overview

Mr. and Mrs. A thank you for taking the time to explain why vaccines are given. You tell them that the 4-month-old is now “behind” in immunizations. Today she will receive vaccines for tetanus, diphtheria, pertussis, Hib, Hepatitis B, polio, and pneumococcus. Mr. A exclaims “Are so many vaccines at one time safe?”

Case

Vaccine Overview

Common Misconceptions• Many people believe giving multiple

vaccines must increase the risk of harmful side effects– URI exposes child to 4-10 antigens– Strep pharyngitis exposes to 25-50 antigens– Body generates a greater immune response

to multiple antigens– Studies show vaccine combinations are safe

and effective

Vaccine Overview

Mrs. A states, “I know someone whose child got the pertussis vaccine, but then she still was diagnosed with whooping cough and hospitalized. How is that possible?”

Case

Vaccine Overview

Common Misconceptions• Some believe vaccines don’t work since

vaccinated children still get disease– No vaccine is 100% effective (most 85-95%)– Example: A measles outbreak occurs in a

high school• Vaccination rate 98%• 27 measles cases occur

– 70% in vaccinated teens (n=19) » “Vaccine failures”

Vaccine Overview

Mrs. A exclaims, “But I thought Emily couldn’t get vaccines today. She’s had a runny nose all week.”

Case

Can You Give Vaccines with a URI Present?–Yes

Vaccine Overview

Other Common Misconceptions• Child needs to have

physical exam first• Can’t be on antibiotics• Had fussiness after last

vaccine• Brother had an adverse

reaction

Vaccine Overview

True Contraindications • Which of the following are true

contraindications to giving vaccines?1. Encephalopathy within 7 days of DTaP2. Prematurity3. Family history of seizures4. Progressive neurological disorder (infantile

spasms)5. Anaphylaxis after DTaP6. Is less than 6 weeks old and needs Hib

Vaccine Overview

True Contraindications1. YES - Encephalopathy within 7 days of DTaP

2. NO - Prematurity

3. NO - Family history of seizures

4. YES - Progressive neurological disorder (infantile spasms)

5. YES - Anaphylaxis after DTaP

6. YES - Is less than 6 weeks old and needs Hib

Vaccine Overview

Mr. A wonders, “I heard that live vaccines are more dangerous. Which of those vaccines she’s getting today is a live one?”

Case

Which Vaccine is Live?–None

Vaccine Overview

Types of Immunity

• Herd Immunity

• Active Immunity

• Passive Immunity

Vaccine Overview

Active Immunity• Vaccinations provide active immunity

• Acquired by surviving infection or receiving vaccination

• Protection produced by the person’s own immune system

• Usually permanent

Vaccine Overview

Immunity• T-cell dependent immunity

– T helper cells carry antigen to activate B

cells to produce antibodies

– Strong memory response generated

– Seen with all vaccines except

polysaccharide vaccines

Vaccine Overview

Immunity• T-cell independent immunity

– Antigen directly stimulates mature B-lymphocytes

– Produces mostly IGM– No memory cells due to lack of plasma cell

stimulation– Poor response by children < 2 years old– Seen primarily with polysaccharide

vaccines

Vaccine Overview

Types of Vaccines• Live-attenuated• Inactivated

– Whole– Fractional– Polysaccharide– Conjugated

Vaccine Overview

Live-attenuated Vaccine (LAV)• Modified “wild-type”

– Retains its ability to replicate– Usually non-infectious– Immune response identical to natural

infection

• Most LAV for viruses• 2 LAV for bacteria

Vaccine Overview

Live-attenuated Vaccine (LAV)• Measles• Mumps• Rubella• Varicella• Zoster (same virus

as varicella vaccine but in higher concentration)

• Rotavirus• Intranasal influenza• Yellow fever• Vaccinia (smallpox)• Oral polio vaccine

(no longer available in the United States)

Currently available live-attenuated viral vaccines

Vaccine Overview

Live-attenuated Vaccine (LAV)• Current LAV against bacteria

– Typhoid

– BCG (not available in U.S.)

Vaccine Overview

True Contraindications for Live Vaccines• NO live vaccines if

– Pregnancy

• During pregnancy

• Up to 4 weeks prior to conception

– Immunosuppression

• HIV with severe suppression (CD4 count < 200)

• On prednisone 20mg daily or 2mg/kg for > 2 weeks

Vaccine Overview

True Concerns for LAV’s• Severe reactions possible

– Usually in persons with immunodeficiency

• Antibody interference– Other live vaccines

• LAV’s must be given together or separated by 28 days

– Exogenous or trans-placental antibodies• Immune globulins like IVIG

• Fragile– Heat and light can damage LAV– Requires careful storage and handling

Vaccine Overview

Inactivated Vaccines• Produced by inactivating virus or

bacteria with heat or chemicals• Cannot replicate or cause disease• Less interference from circulating

antibodies• Generally requires 3-5 doses• Antibody titer decreases with time

Vaccine Overview

Inactivated Vaccine Types• Inactivated whole virus

• Fractional

• Toxin

• Polysaccharide

• Conjugated

Vaccine Overview

Inactivated Vaccines• Inactivated whole virus vaccines

– Polio– Hepatitis A– Rabies

• Toxin vaccines– Diptheria– Tetanus

Vaccine Overview

Inactivated Vaccines• Fractional vaccines

– Composed of virus sub-units

• Influenza

• Hepatitis B

• Acellular pertussis

• Human papilloma virus

• Anthrax

Vaccine Overview

Inactivated Vaccines • Polysaccharide vaccines

– Unique sub-unit vaccine

– Long chain sugar molecules that compose the capsule of an organism

– Minimal booster effect

– Poor response in children < 2 years old• Related to immature immune system

Vaccine Overview

Inactivated Vaccines• Available polysaccharide vaccines

– Pneumococcal 23-valent vaccine

– Meningococcal polysaccharide vaccine (Menomune®)

– Salmonella Typhi vaccine

– The 1st Hemophilus influenza type b vaccine• No longer available in U.S.

Vaccine Overview

Inactivated Vaccines • Conjugated vaccines

– Developed in the late 1980’s– Polysaccharide vaccine conjugated to a

protein– Changes to T-cell dependent immunity • Triggers a strong memory response

– Increased immunogenicity in infants/children

– Allows for booster effect

Vaccine Overview

Inactivated Vaccines• Available conjugated vaccines

– Hib was first – Pneumococcal conjugate• PCV 7 and PCV 13

– Meningococcal conjugate• Menactra™ and Menveo®

Vaccine Overview

Passive Immunity• Transfer of antibody to humans

• Provides temporary disease protection

• Trans-placental transfer to infant is

most common

Vaccine Overview

Passive Immunity• Immune Globulins (Homologous Pooled

Human Antibody) – Made from combined IGG fraction of donated

plasma from thousands of adults– Polyclonal, contains antibodies to multiple diseases– Interferes with live vaccines – Examples

• Post-exposure prophylaxis Hepatitis A (Hep A immune globulin)

• Post-exposure prophylaxis to Measles

Vaccine Overview

Passive Immunity• Homologous Human Hyperimmune

Globulin– Made from human serum with high titers of

desired antibody – Other antibodies may be present due to

human serum– Examples

• Hepatitis B Immune Globulin• Rabies Immune Globulin• Varicella Immune Globulin• Tetanus Immune Globulin

Vaccine Overview

Passive Immunity• Anti-toxins (Heterologous Hyperimmune

Serum)– Animal antibodies made to a disease– Usually made from horses– Risk of serum sickness • Immune reaction to horse protein

– Examples• Botulism anti-toxin• Diphtheria anti-toxin

Vaccine Overview

Passive Immunity• Monoclonal Antibodies

– Developed in laboratory– Clone of single B-cell line specific to disease– Will not interfere with live vaccines– Being used to treat other diseases• Rheumatoid arthritis, non-Hodgkin’s lymphoma,

Crohn’s disease

– Example• RSV (Synagis®)

Vaccine Overview

When Do You Give Vaccines?• Need to know

– Recommended age for dose

– Minimum age for that dose

– Recommended interval to next dose

– Minimum interval to next dose

Vaccine Overview

How Do You Know What to Do?• Epidemiology and Prevention of Vaccine-

Preventable Diseases. The Pink Book: Course Textbook 12th Edition

• On-line resources– www.cdc.gov/vaccines

• (National Immunization Program)

– www.immunize.org/childrules • (Immunization Action Coalition)

– www.cdc.gov/vaccines/programs/iis/contact-state.htm • State Health Department immunization programs

Vaccine Overview

Resources• Centers for Disease Control and

Prevention (CDC) publishes grids for children, adults and catch-up schedules– Laminated cards– Available for hand-held devices– Keep on hand (difficult to memorize)– Need to know general concepts

Vaccine Overview

Recommended Immunization Schedule for Persons Aged 0 through 6 Years

Vaccine Overview

Recommended Immunization Schedule for Persons Aged 7 Through 18 Years

Vaccine Overview

Vaccine Overview

Summary of Adult Vaccinations

Vaccine Overview

What Do You Do if the Child Falls Behind in Immunizations?• DO NOT RESTART THE SERIES

– Follow the minimum interval guidelines

– Some doses may not need to be given

Vaccine Overview

What Do You Do if the Vaccines are Unavailable?• Vaccine shortages occur

– Companies leaving the vaccine market

– Manufacturing or production problems

– Insufficient stockpiles

• Can affect vaccine administration

schedule

Vaccine Overview

What Do You Do if the Vaccines are Unavailable?• Temporary changes may be made in

recommendations for use

– Need to keep records of children who

missed a dose

– Use catch-up table for updates

Vaccine Overview

Vaccine Overview

Immunization Information Systems (IIS)• Mandatory vaccine reporting

• All states and US territories (except New

Hampshire and the Marshall Islands) have

a system

– www.cdc.gov/vaccines/programs/iis/contact-

state.htm

Vaccine Overview

Immunization Information Systems (IIS)• What are some of the benefits of IIS?

– Consolidate immunizations given into one source

– Simplifies record keeping– Easily find records for new patient in practice– Provides official copies of immunization records – Facilitates vaccine reviews of a practice– Is up-to-date with recommendations, so new

vaccines can be flagged to be given to patients– Is free to providers

Vaccine Overview

Immunization Information Systems (IIS)• What could be some parent concerns?

– Confidentiality• IIS must protect privacy of all users• IIS can provide a copy of their confidentiality

statement• Since it is a public health activity, reporting to

IIS is exempt from HIPAA (Health Insurance Portability and Accountability Act of 1996) Privacy Rule

Vaccine Overview

Example:Michigan Care Improvement Registry (MCIR) –Michigan’s Immunization Information System

Vaccine Overview

Vaccine Information Sheets (VIS)• One-page (2-sided) information sheets

describing risks and benefits of vaccines

• Produced by CDC• Federal law mandates VIS must be

given for each vaccine listed in the National Childhood Vaccine Injury Act of 1986

Vaccine Overview

Vaccine Information Sheets (VIS)• As of June 2009, must

give VIS for– DTaP – MMR – Polio – Hepatitis A – Hepatitis B – Hib – Varicella – Influenza – Pneumococcal Conjugate

Vaccine Overview

Vaccine Information Sheets (VIS)• Given to each recipient or his/her

parent/guardian prior to administration of each dose of vaccine.– May be available electronically or on paper– May be read before the visit– Edition date of the VIS must be recorded in

permanent medical record

Vaccine Overview

Vaccine Information Sheets (VIS)• Are updated as needed

• Available at http://www.cdc.gov/vaccines

or from state health department

• Available in 37 languages

Vaccine Overview

Sample VIS

Vaccine Overview

Vaccine Adverse Event Reporting System (VAERS)• National vaccine safety surveillance system co-

sponsored by CDC and FDA• Collects information about adverse events and

possible side effects• VAERS Table of Reportable Events Following

Vaccination indicates what providers must report (http://vaers.hhs.gov/resources/VAERS_RET.pdf)– Examples: anaphylaxis, encephalopathy,

thrombocytopenic purpura

Vaccine Overview

Vaccine Adverse Event Reporting System (VAERS)• Individuals can report adverse reactions

on-line, fax or mail form http://vaers.hhs.gov/esub/index

• Limitations– Under-reporting? – Selective reporting?– Does not establish causality– Can not calculate rates of adverse reactions

from data

Vaccine Overview

Summary• Medical knowledge

– Types of Immunity• Herd – most of population immune to the disease• Active – acquired by the disease or immunization• Passive – antibodies given

– Live-attenuated vaccine – non-infectious virus/bacteria stimulates immune response

– Inactivated vaccine types – Whole, fractional, polysaccharide, conjugated

Vaccine Overview

Summary• Medical knowledge

– True contraindications to vaccines• NO live vaccines to pregnant or immune-

compromised patients• Anaphylaxis• Progressive Neurological Disorder (infantile

spasms)• Encephalopathy within 7 days of DTaP• Hib should only be given to an infant 6 or more

weeks of age

Vaccine Overview

Summary• Interpersonal communication

– Explaining reasons for immunization to

parents or guardian takes time.

• Evidence supports vaccines decrease disease

and are safe and effective

• CDC provides tools to assist giving information

to patients

Vaccine Overview

Summary• Systems-based practice

– Each state has an Immunization Information System accessible on the internet at www.cdc.gov/vaccines/programs/iis/contact-state.htm

– Through IIS, providers know what vaccines a person has received and which vaccines they need.

Vaccine Overview

Summary• Systems-based practice

– Vaccine Information Sheets (VIS) list the risk and benefits of each vaccine and must be given prior to the administration of most vaccines

– Individuals and health care providers can report possible vaccine side effects to the Vaccine Adverse Event Reporting System (VAERS)