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Childhood Vaccines DTaP, Polio, HiB, Hep B, Prevnar Continuity Clinic Lecture July 9, 2009. Objectives:. Brief review of diseases Individual and combination vaccines Vaccine Schedules Side Effects and Contraindications. Diphtheria. Greek diphthera (leather hide)
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Childhood Vaccines DTaP, Polio, HiB, Hep B, Prevnar Continuity Clinic Lecture July 9, 2009
Objectives: • Brief review of diseases • Individual and combination vaccines • Vaccine Schedules • Side Effects and Contraindications
Diphtheria Greek diphthera (leather hide) Recognized by Hippocrates in 5th century BCE Epidemics described in 6th century C. diphtheriae described by Klebs in 1883 Toxoid developed in 1920s
Corynebacterium diphtheriae Aerobic gram-positive bacillus Toxin production occurs only when C. diphtheriae infected by virus (phage) carrying tox gene If isolated, must be distinguished from normal diphtheroid
Diphtheria Clinical Features Incubation period 2-5 days (range, 1-10 days) May involve any mucous membrane Classified based on site of infection anterior nasal pharyngeal and tonsillar laryngeal cutaneous ocular genital
Pharyngeal and Tonsillar Diphtheria Insidious onset of exudative pharyngitis Exudate spreads within 2-3 days and may form adherent membrane Membrane may cause respiratory obstruction Fever usually not high but patient appears toxic
Diphtheria Complications Most attributable to toxin Severity generally related to extent of local disease Most common complications are myocarditis and neuritis Death occurs in 5%-10% for respiratory disease
Diphtheria Antitoxin Produced in horses First used in the U.S. in 1891 Used only for treatment of diphtheria Neutralizes only unbound toxin
Diphtheria Epidemiology Reservoir Human carriers Usually asymptomatic Transmission Respiratory Skin and fomites rarely Temporal pattern Winter and spring Communicability Up to several weeks without antibiotics
Diphtheria – United States, 1980-2004Age Distribution of Reported Cases N=53
Routine DTaP Primary Vaccination Schedule Dose Primary 1 Primary 2 Primary 3 Primary 4 Age 2 months 4 months 6 months 15-18 months Interval --- 4 wks 4 wks 6 mos
Routine DTaP Schedule for Children Younger Than 7 Years of Age 4 through 6 years of age, before entering school 11 or 12 years of age if 5 years since last dose (Tdap) Every 10 years thereafter (Td) Booster Doses
Diphtheria and Tetanus ToxoidsAdverse Reactions Local reactions (erythema, induration) Exaggerated local reactions (Arthus-type) Fever and systemic symptoms not common Severe systemic reactions rare
Diphtheria and Tetanus ToxoidsContraindications and Precautions Severe allergic reaction to vaccine component or following a prior dose Moderate or severe acute illness
Tetanus First described by Hippocrates Etiology discovered in 1884 by Carle and Rattone Passive immunization used for treatment and prophylaxis during World War I Tetanus toxoid first widely used during World War II
Clostridium tetani Anaerobic gram-positive, spore-forming bacteria Spores found in soil, animal feces; may persist for months to years Multiple toxins produced with growth of bacteria Tetanospasmin estimated human lethal dose = 2.5 ng/kg
Tetanus Pathogenesis Anaerobic conditions allow germination of spores and production of toxins Toxin binds in central nervous system Interferes with neurotransmitter release to block inhibitor impulses Leads to unopposed muscle contraction and spasm
Tetanus Clinical Features Incubation period; 8 days (range, 3-21 days) Three clinical forms: local (not common), cephalic (rare), generalized (most common) Generalized tetanus: descending symptoms of trismus (lockjaw), difficulty swallowing, muscle rigidity, spasms Spasms continue for 3-4 weeks Complete recovery may take months
Neonatal Tetanus Generalized tetanus in newborn infant Infant born without protective passive immunity Estimated more than 250,000 deaths worldwide in 2000-2003* *www.who.int/immunization_monitoring/diseases/neonatal_tetanus/en/index.html
Tetanus Complications Laryngospasm Fractures Hypertension Nosocomial infections Pulmonary embolism Aspiration pneumonia Death
Tetanus Epidemiology Reservoir Soil and intestine of animals and humans Transmission Contaminated wounds Tissue injury Temporal pattern Peak in summer or wet season Communicability Not contagious
Tetanus—United States, 1947-2007 Year *2005 provisional total
Tetanus—United States, 1980-2007 Year *2005 provisional total
Tetanus Toxoid Formalin-inactivated tetanus toxin Schedule Three or four doses + booster Booster every 10 years Efficacy Approximately 100% Duration Approximately 10 years Should be administered with diphtheria toxoid as DTaP, DT, Td, or Tdap
Pertussis Highly contagious respiratory infection caused by Bordetella pertussis Outbreaks first described in 16th century Bordetella pertussis isolated in 1906 Estimated 294,000 deaths worldwide in 2002
Bordetella pertussis Fastidious gram-negative bacteria Antigenic and biologically active components: pertussis toxin (PT) filamentous hemagglutinin (FHA) agglutinogens adenylate cyclase pertactin tracheal cytotoxin
Pertussis Pathogenesis Primarily a toxin-mediated disease Bacteria attach to cilia of respiratory epithelial cells Inflammation occurs which interferes with clearance of pulmonary secretions
Pertussis Clinical Features Incubation period 5-10 days (range 4-21 days) Insidious onset, similar to minor upper respiratory infection with nonspecific cough Fever usually minimal throughout course of illness
Pertussis Clinical Features Catarrhal stage 1-2 weeks Paroxysmalcough stage 1-6 weeks Convalescence Weeks to months
Pertussis Among Adolescents and Adults Disease often milder than in infants and children Infection may be asymptomatic, or may present as classic pertussis Persons with mild disease may transmit the infection Older persons often source of infection for children
Pertussis Deaths in the United States, 2004-2006 2004 2005 2006 Total Age at onset <3 mos 24 32 13 69 (84%) >3 mos 3 7 3 13 (16%) Total 27 39 16 82 CDC, unpublished data, 2007
Pertussis Complications by Age* *Cases reported to CDC 1997-2000 (N=28,187)
Whole-Cell Pertussis Vaccine Developed in mid-1930s and combined as DTP in mid-1940s 70%-90% efficacy after 3 doses Protection for 5-10 years Local adverse reactions common
Pertussis-containing Vaccines DTaP (pediatric) approved for children 6 weeks through 6 years (to age 7 years) Tdap (adolescent and adult) approved for persons 10 through 64 years (Boostrix) and 11 through 64 years (Adacel)
DTaP Fourth Dose Recommended at 15-18 months* May be given at 12 months of age if: child is 12 months of age, and 6 months since DTaP 3rd dose, and unlikely to return at 15-18 months *15-20 months for Daptacel
School Entry (Fifth) Dose Fifth dose recommended when 4th dose given before age 4 years All DTaP vaccines are licensed for 5th dose after DTaP series
Interchangeability of Different Brands of DTaP Vaccine Whenever feasible, the same DTaP vaccine should be used for all doses of the series Limited data suggest that “mix and match” DTaP schedules do not adversely affect safety and immunogenicity If vaccine used for earlier doses is not known or not available, any brand may be used to complete the series
Pediarix DTaP – Hep B – IPV combination Minimum age 6 weeks Approved for 3 doses at 2, 4 and 6 months Not approved for booster doses Licensed for children 6 weeks to 7 years of age
Pediarix May be used interchangeably with other pertussis-containing vaccines if necessary Can be given at 2, 4, and 6 months in infants who received a birth dose of hepatitis B vaccine (total of 4 doses) May be used in infants whose mothers are HBsAg positive or status unknown* *off-label ACIP recommendation www.cdc.gov/vaccines/programs/vfc/downloads/resolutions/1003hepb.pdf
Pentacel Vaccine Contains lyophilized Hib (ActHIB) vaccine that is reconstituted with a liquid DTaP-IPV solution Approved for doses 1 through 4 among children 6 weeks through 4 years of age The DTaP-IPV solution should not be used separately (i.e., only use to reconstitute the Hib component)
DTaP Adverse Reactions Local reactions 20%-40% (pain, redness, swelling) Temp of 101oF 3%-5% or higher More severe adverse reactions not common Local reactions more common following 4th and 5th doses
Adverse Reactions Following the 4th and 5th DTaP Dose Local adverse reactions and fever increased with 4th and 5th doses of DTaP Reports of swelling of entire limb Extensive swelling after 4th dose NOT a contraindication to 5th dose