Chapter 116. Immunization Principles and Vaccine Use (Part 6) potx

Immunization Principles and Vaccine Use Part 6 Risk Assessment Vaccines are considered safe when the risk of use is judged to be acceptable in relation to the benefits.. oppose mandat

Chapter 116 Immunization Principles

and Vaccine Use

(Part 6)

Risk Assessment

Vaccines are considered safe when the risk of use is judged to be acceptable

in relation to the benefits For vaccines given to healthy individuals for diseases that are no longer common, acceptable risks are set at very low levels—indeed, far lower than for most medical products However, "safety" does not and cannot ever mean "zero risk." The determination of safety is thus based on a scientific assessment of the data and a considered judgment of all the issues involved, including benefits and risks Communities and individuals may differ, both among themselves and from health care professionals, in how they perceive the risks, benefits, and acceptability of vaccines and in how they judge the amount of uncertainty that is tolerable Some parent advocacy groups, such as those that

oppose mandatory vaccination, feel that no amount of risk is acceptable, especially for childhood vaccines

Sources of Immunization Recommendations

Harmonized recommendations for vaccine use in the United States are developed by several professional groups Schedules for immunization of children and adolescents and of adults are shown in Figs 116-1 and 116-2, respectively Vaccines recommended for special use are shown in Table 116-2

Table 116-2 Special Vaccines for Infants, Children, and Adults

Vacci

ne

Vacc ine Type

Rou

te of Administr ation

Indic ations

Effi cacy

Adverse Events

Anthra

x

Inact ivated avirulent

SC (6 doses primary plus annual

For high risk of exposure (e.g., persons

90

% antibody response;

No serious adverse effects known

bacteria booster) in contact

with or involved in manufacture

of animal hides, furs, bone meal, wool, goat hair) and military risk

of biowarfare exposure

efficacy uncertain

Tuber

culosis

(BCG)

Live bacteria (attenuated

Mycobacter ium bovis)

generally recommende

d in U.S

because of low risk of

Var iable for adult pulmonary TB; best used to prevent

Regional adenitis,

disseminated BCG infection in immunocompromi sed hosts

interference

with PPD

test

Consi

der for

PPD-negative

children in

prolonged

contact with

ineffectively

treated adult

TB patients

or those with

drug-resistant TB

and for

health care

workers in

high-risk

settings

childhood

TB, meningitis

miliary disease

Not for

immunosupp ressed individuals

Choler

a

Kille

d whole bacteria

Oral Travel

endemic areas;

however, not recommende

d for use by U.S citizens because of extremely low risk Not available in the U.S

60–

85%, short duration

Frequent fever and local reactions, pain, swelling

Plague Inact

ivated

bacteria

atory workers;

foresters in endemic areas;

?travelers

90

% antibody response;

efficacy uncertain

10% local reactions; rare sterile abscess and hypersensitivity

Rabies Inact

ivated virus

grown in

cell culture

(human

diploid cell

or purified

chick

embryo

cell) or

grown in

cell culture

and

IM

or ID

Preex posure immunizatio

travelers to high-risk countries, laboratory workers, and veterinarians

or postexposure immunizatio

Virt ually 100% for pre- or postexpos ure immunizat ion

25% local reactions; 6% of patients receiving booster doses may develop immune complex reactions with arthropathy, arthritis,

angioedema

adsorbed to aluminum phosphate

n following a bite from a proven or suspected rabies-infected animal

Yello

w fever

Live attenuated virus

endemic areas;

laboratory workers

Hig

h

Rare associated neurologic complications (encephalitis, encephalopathy)

or viscerotropic disease (fever; hypotension; respiratory, renal,

or hepatic failure; lymphocytopenia; thrombocytopenia

; and high risk of death)

Japane

encephalitis

Inact ivated virus

endemic areas

80–

90%

Anaphylaxi s/severe delayed allergic reactions common;

recipients should

be observed for

10 days

Typho

id

Purif ied Vi polysacchar ide (not for children <2 years of age)

ers (≥2 years old) to high-risk areas (southern Asia and other

developing areas) except febrile

50–

80%

Local reactions, mild

patients

Oral live

attenuated Ty21a strain

Oral Travel ers (≥6 years old) to high-risk areas as above,

except within 24 h

of antibiotic ingestion or

in febrile patients

50–

80%

Nil

Note: SC, subcutaneous; BCG, bacille Calmette-Guérin; ID, intradermal;

PPD, purified protein derivative; TB, tuberculosis

Source: Recommendations of the Advisory Committee on Immunization

Practices of the Centers for Disease Control and Prevention, American Academy

of Pediatrics, American College of Physicians