pharmacists as immunizer part 1

immunity

body’s ability to prevent invasion of pathogens

vaccine

a preparation used to stimulate the body’s immune response against diseases

immunization

a process by which a person becomes protected against a disease through vaccination

vaccination

an act of introducing a vaccine into the body to produce protection from a specific disease

types of immunity

• active

• passive

active immunity

results when exposure to a disease organism triggers the immune system to produce antibodies to that disease

active immunity (natural)

infection

active immunity (artificial )

vaccine

passive

is provided when a person is given antibodies to a disease rather than producing them through his or her own immune system

passive (natural)

maternal antibodies

pasive (artificial)

monoclonal antibodies

when a new pathogen or disease enters our body,

it introduces a new antigen.

for every new antigen, our body needs to __

build specific antibody that can grab onto the antigen and defeat the pathogen

vaccine

is a tiny weakened non-dangerous fragment of the organism and includes parts of the antigen. it is enough that our body can learn to build the specific antibody. then if the body encounters the real antigen later, as part of the real organism, it already knows how to defeat it

community immunity

vaccinating not only protects you but also protects those in the community who are unable to be vaccinated

philippine health situation

triple burden of disease

• infectious diseases are still common

• non communicable diseases are on the rise

• disaster-related health prroblems increasingly affect the country

HEALTH INDICATORS

1. High incidences of all key communicable diseases with 13 out of 17 WHO recognized neglected tropical diseases remaining endemic

2. Increasing level of non-communicable diseases and high prevalence of all risk-factors

3. Being the third highest disaster-prone country in the world.

50% of the population:

living on less than $2 a day despite a 4% GDP growth annually for the past decade

FACTORS THAT CONTRIBUTE TO THE RISE OF INFECTIOUS DISEASES

1. Prevalence of malnutrition plays a part in lowering resistance to infections

2. Increased number of immunocompromised patients due to NCDs

3. Increased hospitalizations predispose patients to nosocomial infections

4. Emergency situations during disasters like:

• lack of potable water

• poor sanitation

• malnutrition

• increased concentration of the population in evacuation: outbreaks

5. Poverty and heavy burden on individuals and the health system to respond to treatment and needs of the population highlight the importance of preventive measures

Prevalence of malnutrition

plays a part in lowering resistance to infections

Increased number of immunocompromised patients due to

NCDs

Increased hospitalizations

predispose patients to nosocomial infections

Emergency situations during disasters like:

• lack of potable water

• poor sanitation

• malnutrition

• increased concentration of the population in evacuation: outbreaks

Poverty and heavy burden on individuals and the health system to

respond to treatment and needs of the population highlight the importance of preventive measures

PREVENTION OF INFECTION AND INFECTIOUS DISEASES

• Protecting against establishment of an infection

• Sterilizing immunity (complete prevention of infection)

Protecting against establishment of an infection 

Hepatitis A vaccine

90% protections against symptomatic disease and asymptomatic infections

Sterilizing immunity (complete prevention of infection)

HPV / Human papilloma virus

• ability to completely prevent persistent vaccine-type infection

CONTROL OF MORTALITY, MORBIDITY, AND COMPLICATIONS

• Pre-exposure administration 

• Post-exposure administration 

• Pre-exposure administration

• Pre-exposure vaccination with a combination of several antigens- successful

• Post-exposure administration 

• Rabies

• Hepatitis A and B

• Measles

• Varicella

• Groups that are most vulnerable to infections and with the greatest need:

• pregnant women

• cancer patient

• immunocompromised individuals

Vaccines can annually prevent almost

6 million deaths worldwide.

Failure to prevent infections:

• Congenital rubella syndrome

• Liver cirrhosis 

• Cancer

• Measles and mumps (may lead to neurological problems)

PROTECTION OF THE UNVACCINATED POPULATION

• “Herd Protection” of an unimmunized individual

Herd Protection

first mechanism

reducing amount and/or duration of pathogen shedding, thereby retarding transmission

Second Mechanism

through what is called “contact immunization,”- where vaccine viruses may infect more individuals than those administered vaccine

SOCIETAL AND ECONOMIC BENEFITS OF IMMUNIZATION

• Protective effects of vaccines translate into long-term cost savings

SAFE TRAVEL AND MOBILITY

• MOST COMMON vaccine-preventable diseases among travelers are:

• Influenza

• Hepatitis A.

SAFE TRAVEL AND MOBILITY

others

• Rabies

• Hepatitis B

• typhoid

• cholera

• yellow fever

• Japanese encephalitis

• measles

PROTECTION AGAINST BIOTERRORISM

• Cessation in the potential use of smallpox virus in bioterrorism

ENHANCING EQUITY

• ”perinatal and early infancy period”

MAIN TARGETS OF IMMUNIZATION PROGRAMS

• disease eradication

• disease elimination

Disease Eradication

Totally eradicated: SMALLPOX

Disease Elimination

• Locally achieving immunity in more than 95% if the population

• Combined measles, mumps and rubella (MMR) vaccine could eliminate rubella and mumps.

CHALLENGES

1. With environmental reservoir (Tetanus) or those coming from animal reservoir (Japanese encephalitis and rabies)

2. Misconceptions and the rise of the anti-vaccination movement

PHARMACISTS IN IMMUNIZATION PROGRAMS

1. Pharmacists, involved with immunizations, are able to utilize their practice settings to advocate for immunization

2. Pharmacists are able to increase their responsibilities in the area of Public Health.

PURPOSE OF PHARMACISTS-RUN IMMUNIZATION CLINICS

• to provide an alternative resource for immunization

• a resource person for immunization information

• as an entry point for patients to receive immunization through the health system

CONSIDERATIONS IN ESTABLISHING PHARMACY-BASED IMMUNIZATION SERVICES

Education and Training

Curricula:

• incorporate the immunization program as an elective to promote the role of the pharmacist in preventive health

• continuing education programs and resources

GUIDELINE 1: PREVENTION

• Pharmacists should protect their patients’ health by being vaccine advocates.

GUIDELINE 1:

PREVENTION

GUIDELINE 1: PREVENTION

• Pharmacists should adopt one of three levels of involvement in vaccine advocacy

  • pharmacist as educator (motivating people to be immunized

  • pharmacist as facilitator (hosting others who immunize)

  • pharmacist as immunizer

• Pharmacists should adopt one of three levels of involvement in vaccine advocacy

• pharmacist as educator (motivating people to be immunized

• pharmacist as facilitator (hosting others who immunize)

• pharmacist as immunizer

GUIDELINE 2: PARTNERSHIP

• Pharmacists should administer immunizations and do so in partnership with their community.

GUIDELINE 2:

PARTNERSHIP

GUIDELINE 3: QUALITY

• Pharmacists must achieve and maintain competence to administer immunizations.

GUIDELINE 3:

QUALITY

GUIDELINE 4:

DOCUMENTATION

GUIDELINE 4: DOCUMENTATION

• Pharmacists should document immunizations fully and report clinically significant events.

GUIDELINE 5:

EMPOWERMENT

GUIDELINE 5: EMPOWERMENT

• Pharmacists should educate patients about immunizations and respect patients’ rights.

PRODUCT DEVELOPMENT OF VACCINES

• Long (May take years)

• Complex

• Costly

PRODUCT DEVELOPMENT OF VACCINES

• A different, more stringent set of Good Manufacturing Practices provided for vaccines (Biological products)

Biologicals

are produced using materials that are part of or were parts of a living material

PRODUCT DEVELOPMENT OF VACCINES

• Substances reflect the inherent variability characteristic of living materials.

Vaccine Formulation Development:

the process of discovering a potential vaccine immunogen and developing it into a fully approved vaccine.

Vaccine Formulation Development:

• converting vaccine antigens to medicines

VACCINE FORMULATION DEVELOPMENT PATH

1. Physical and Chemical characterization of the antigenic component.

2. Development of stability-indicating assays including potency.

3. Evaluation and Optimization of the route of administration and adjuvants (in both animal models and in clinical trials).

4. Formulation design to maximize the candidate vaccine’s stability, shelf-life and immunogenic potential.

MAIN TYPES OF VACCINES (WHO)

1. live attenuated

2. inactivated

3. subunit

4. toxoid

5. mRNA

6. viral vector

LIVE ATTENUATED (LAV)

• Derived from disease causing pathogens (virus or bacteria) that have been weakened (attenuated) under lab conditions'

• Typically 1-2 doses can give lifetime protection

LIVE ATTENUATED (LAV)

immune response

• Provide continual antigenic stimulation, giving sufficient time for memory cell production

EXCELLENT IMMUNE RESPONSE

LIVE ATTENUATED (LAV)

safety and stabillity

• Can revert to original form and cause disease

• Potential harm to individuals with compromised immune systems

• Sustained infection (BCG-local lymphadenitis)

• Contamination of tissue culture

• Immunization errors (reconstitution, cold chain)

• Usually not given in pregnancy

• LESS SAFE COMPARED TO INACTIVATED VACCINE

LIVE ATTENUATED (LAV)

examples

• Tuberculosis (BCG)

• Oral Polio Vaccine (OPV)

• Measles, Mumps, Rubella (MMR)

• Rotavirus

• Yellow fever 

• Varicella

INACTIVATED (KILLED ANTIGEN)

immune response

• May not always induce immune response at first dose

• Response may not be long-lived requiring several doses of vaccine 

• LESS STRONG IMMUNE RESPONSE COMPARED TO LIVE VACCINE

INACTIVATED (KILLED ANTIGEN)

safety and staibility

• Have no live components no risks of inducing the disease 

• Safer and more stable than LAVs

• EXCELLENT STABILITY PROFILE

INACTIVATED (KILLED ANTIGEN)

examples

• Whole-cell Pertussis (wP)

• Inactivated Polio Virus (IPV)

INACTIVATED (KILLED ANTIGEN)

• Made from microorganisms (virus, bacteria, others) that have been killed through physical and chemical processes

• Requires several doses

SUBUNIT (PURIFIED ANTIGEN)

• Contain only the killed, antigenic parts of the pathogen necessary to elicit a protective immune response

• Requires several doses (booster shots)

SUBUNIT (PURIFIED ANTIGEN)
immune response

• Must determine which combination of antigenic properties will produce an effective immune response with the correct pathway

• Response may be elicited, but with no guarantee that memory will form for future responses

• LESS STRONG IMMUNE RESPONSE COMPARED TO LAVs

SUBUNIT (PURIFIED ANTIGEN)

safety and stability

• Have no live components

• No risk of inducing the disease Safer and more stable than LAVs 

• EXCELLENT STABILITY PROFILE

SUBUNIT (PURIFIED ANTIGEN)

examples

• Hepatitis B (HepB)

• Haemophilus influenzae type b (Hib)

• Pneumococcal 

• Acellular pertussis

TOXOID (INACTIVATED TOXINS)

• The protein based toxin is rendered harmless (Toxoid) and used as antigen to elicit immunity

• May require booster shots

TOXOID (INACTIVATED TOXINS)

immune response

• May require several doses and usually need an adjuvant

• NOT HIGHLY IMMUNOGENIC

TOXOID (INACTIVATED TOXINS)

safety and stability

• Vaccine cannot cause disease it prevents 

• Very rare local and systemic reactions 

• Usually stable and long lasting 

• EXCELLENT STABILITY PROFILE

TOXOID (INACTIVATED TOXINS)

examples

• Tetanus Toxoid (TT)

• Diphtheria Toxoid

 mRNA

Creates proteins in order to trigger response

 mRNA

examples

• COVID-19  (Pfizer, Moderna)

 VIRAL VECTOR

• Modified version of a different pathogen as a vector to deliver protection 

• The viral vector is a virus that does NOT cause serious illness 

The viral vector is a virus that does NOT cause serious illness 

• e.g. adenovirus or modified vaccina Ankara virus

 VIRAL VECTOR

examples

• COVID-19  (Janssen / Johnson & Johnson , AstraZeneca)

VACCINE COMPONENTS/FORMULATION

• antigens

• stabilizers

• adjuvants

• antibiotics

• preservatives

ANTIGENS

• Derived from the disease causing organisms 

STABILIZERS

Maintain the effectiveness by maintaining stability of the product during storage, particularly where the cold chain is unreliable

STABILIZERS

• e.g. MgCl₂ (for OPV), 

• MgSO₄ (for measles), 

• lactose sorbitol and sorbitol-gelatin

• 2-phenoxy ethanol

ADJUVANTS

• To stimulate the production of antibodies against the vaccine to make it more effective

• Ability to enhance the immune response

ADJUVANTS

• e.g. Aluminum gels or Aluminum salts

ANTIBIOTICS

• in trace amounts

• Used during the manufacturing phase to prevent bacterial contamination of the tissue culture cells in which the viruses are grown

PRESERVATIVES

• Added to multi-dose vaccines 

PRESERVATIVES

• e.g. thimerosal (ethyl mercury-containing compound) 

PRESERVATIVES

formaldehyde

formaldehyde

•  to inactivate viruses (IPV), to detoxify bacterial toxins (diphtheria and tetanus)