INFECTION PREVENTION IN CHILDREN
Educational Objectives
| The goal of this program is to prevent transmission of infectious disease among children. After hearing and assimilating
this program, the clinician will be better able to:
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 | 1. Describe the morbidity and mortality associated with vaccine-preventable childhood diseases.
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| 2. Implement evidence-based recommendations for childhood immunizations and booster vaccines.
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| 3. Discuss the clinical impact of vaccinating adolescent girls against human papillomavirus.
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| 4. Counsel patients and families about nutritional supplements.
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| 5. Educate families about practices for reducing infection.
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Faculty Disclosure
In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty and members of the
planning committee to disclose relevant financial relationships within the past 12 months that might create any personal
conflicts of interest. Any identified conflicts were resolved to ensure that this educational activity promotes
quality in health care and not a proprietary business or commercial interest. For this program, the faculty and planning
committee reported nothing to disclose.
Acknowledgments
Dr. McNamara was recorded at Annual Review in Family Medicine–Controversies and Challenges in Primary Care,
presented by University of California, San Francisco, School of Medicine, and held April 6-8, 2008, in San Francisco,
CA. Dr. Rotbart was recorded at 60th Anniversary and Annual Scientific Conference, presented by the Colorado
Academy of Family Physicians, and held July 18-20, 2008, in Estes Park, CO. The Audio-Digest Foundation thanks
the speakers and the sponsors for their cooperation in the production of this program.
| VACCINES 2008: NEW GUIDELINES— Margaret M. McNamara, MD, Associate Clinical Professor, Department of Pediatrics,
University of California, San Francisco, School of Medicine
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Rotavirus
| Epidemiology: infects 4 of 5 children by 5 yr of age in United States; most cases of severe illness occur in children ≤3 yr of
age; disease fatal in 1 in 200,000 cases; rotavirus responsible for 30% to 70% of hospital admissions for acute gastroenteritis
in children; important cause of diarrhea acquired in hospital and day care settings; annual cycle of outbreaks
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| Serotypes: defined by surface proteins; four strains responsible for 96% of disease worldwide; serotypes vary regionally
and from year to year
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| Transmission: fecal-oral route; airborne droplets hypothesized as second route; infected stool has extremely high viral
load; small dose required for infection; short incubation period
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| Clinical manifestations: fever (50% of children); nonbilious vomiting (80%-90%); 10 to 20 episodes of diarrhea per day;
symptoms last 3 to 8 days; risk—children 3 to 35 mo of age at highest risk for dehydration and electrolyte disturbances;
immunodeficiency increases risk; illness severity typically decreases with repeated exposures; full-term neonates protected
by maternal IgG; prevention—clean water supply and hygiene practices have little effect on transmission
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| Vaccines: previous versions withdrawn due to low efficacy or increased risk for intussusception (mostly in infants receiving
first dose at 3-7 mo of age); Rotarix—available in Europe; prepared from one human strain; replicates well in intestine;
shed in stool; RotaTeq—licensed in United States; combination of 5 bovine-human reassortants; replicates poorly
in gut; ≈10% shed in stool; pentavalent vaccine—significantly reduces incidence, hospitalization, and visits to ED; prevents
98% of severe disease; incidence of severe adverse events similar between vaccine and placebo groups; no confirmed
cases of intussusception within 42 days of first dose (high-risk period with previous vaccine); no evidence of
clustering after doses; at 1 yr, no different from placebo; guidelines—first dose given between 6 and 12 wk of age (do
not initiate series after 12 wk of age); subsequent doses at 4- to 10-wk intervals; final dose no later than 32 wk of age;
contraindications—severe hypersensitivity to any component of vaccine or to previous dose; precautions—
immunocompromised infants (no data on safety); moderate to severe illness (delay vaccine until child well; acceptable to
administer vaccine to child with mild illness or low-grade fever); other considerations—if child regurgitates dose, do
not repeat (increases risk for dose-related adverse effects), but give subsequent doses on schedule; vaccinate nonhospitalized
preterm infants based on chronologic age; acceptable to administer vaccine at same time as other routine vaccines
(but, unknown effect on pertussis vaccine)
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Meningococcus
| Epidemiology: leading cause of bacterial meningitis in children; 1400 to 3000 cases of invasive disease each year in United
States; fatal in 10% to 14% of cases; 11% to 19% of patients have significant sequelae; invasive disease—most cases
caused by Neisseria, serotypes A, B, C, Y, and W-135 (serotypes B, C, and Y in United States); average incubation period,
4 days; rapid production of endotoxin may be fatal within 48 hr; typically sporadic, but localized outbreaks occur;
transmission—contact with aerosolized droplets or nasopharyngeal secretions; peak incidence—infants <1 yr of age
at highest risk; second peak occurs at 15 to 18 yr of age; invasive disease among adolescents —mortality ≈20%; increased
rates of meningococcemia and shock (compared to infants); risk factors—complement deficiency; anatomic or
functional asplenia; traveling or living in hyperendemic areas; college freshmen living in dormitories
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| Vaccines: Menomune (MPSV4)—used in patients \>2 yr of age, at high risk for disease; Menactra (MCV4)—approved
for use in patients 11 to 55 yr of age; trials in younger age groups in progress; comparison of vaccines—both contain
capsular polysaccharides for serotypes A, C, Y, and W-135 (conjugated to diphtheroid toxin in Menactra); antibodies develop
in 1 wk; Menomune stimulates mature B lymphocytes but not T lymphocytes; Menactra does not interact with
other immunizations; similar safety profiles; Menactra (intramuscular injection) associated with more injection site pain
than Menomune (subcutaneous injection); adverse effects generally mild and include headache, fatigue, and fever; allergic
reactions rare; Guillain-Barré syndrome (GBS)—some reports of onset within 2 to 5 wk after administration of
Menactra; significance unknown; history of GBS contraindication for vaccine; efficacy—T-cell–dependent immune response
that occurs with Menactra may confer advantage (eg, anamnestic response at reexposure); Menactra associated
with reduced nasopharyngeal carriage and longer immunity
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| Recommendations: routine vaccination with Menactra at 11 to 12 yr of age or at entry to high school; also appropriate for
college freshmen living in dormitories, military recruits, individuals with laboratory exposure to Neisseria, patients with
complement deficiency or asplenia, and travelers and residents in hyperendemic areas
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Human Papillomavirus (HPV)
| Background: causative agent of cervical cancer; one of most common sexually transmitted infections in United States
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| Epidemiology: United States—lifetime risk of acquiring infection, 50%; annual incidence, ≈6.2 million; prevalence, ≈20
million; 28% to 46% of women <25 yr of age infected
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| Cervical cancer: ≈20 oncogenic serotypes; serotypes 16 and 18 responsible for ≈66% of cervical cancers worldwide and
≈75% of cases in United States; nononcogenic types 6 and 11 most often associated with external genital warts; US
data—≈9700 new cases/yr; 3700 deaths/yr; 1.4 million new cases of low-grade and 330,000 new cases of high-grade
cervical dysplasia each year
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| HPV infection: transmission—sexual contact; condom use may reduce but does not eliminate risk; vertical transmission
may occur between mother and newborn; contaminated fomites may pose risk; risk factors in women—highest risk between
20 and 24 yr of age; increased number of sexual partners; early age of sexual debut; uncircumcised male partners;
risk factors in men—highest risk between 25 and 29 yr of age; receptive anal intercourse; being uncircumcised;
clearance—≈80% of infections in women (15 to 25 yr of age), clear spontaneously, possibly through cell-mediated immune
response; median duration of infection, 8 mo; serotypes 16 and 18 more likely to persist; persistence—associated
with development of cervical precancer and cancer; natural history—risk for progression to cancer affected by age, infection
with multiple serotypes, and immune suppression; most infections clear within 1 to 2 yr; persistent infections may
progress to low- or high-grade dysplasia, and eventually to invasive cancer
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| Vaccine: targets serotypes 6, 11, 16, and 18; efficacy—good protection from persistent infection with vaccine-covered serotypes;
no evidence of protection against existing disease; infection with one serotype does not diminish efficacy against
other vaccine-covered serotypes; protection lasts ≥5 yr; need for booster unknown; recommendations—routine vaccination
of girls, 11 to 12 yr of age (approved for use in patients 9-26 yr of age); acceptable to administer vaccine at same
time as other scheduled vaccines; second dose given 36 days to 2 mo after first dose; third dose given 80 days to 6 mo after
second dose; targeting adolescents—high prevalence of infection limits ability to identify high-risk individuals;
best to vaccinate before sexual debut; good access to patients and high antibody titers at this age; precautions and
contraindications—moderate or severe acute illness (defer dose); hypersensitivity or severe allergic reaction to yeast or
any other component of vaccine (contraindication); cervical cancer screening—possibility of preexisting infection or
subsequent infection with serotype not covered by vaccine necessitates continued screening; results from screening or
other testing should not affect decision to vaccinate; future considerations—postmarketing surveillance for safety and
efficacy; surveillance of HPV-related outcomes; efficacy study in men
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Tetanus, Diphtheria, Acellular Pertussis (TDAP)
| Background: acellular pertussis component from pediatric formulation, added to tetanus-diphtheria (Td) vaccine; history—
before availability of vaccine for pertussis, disease primarily affected preschool-aged children; immunization initiated in
1940s; incidence plummeted, but has increased steadily since 1980s
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| Epidemiology of pertussis: remains endemic; incidence increasing despite universal childhood immunization; peaks occur
in infants < 6 mo of age and in teens; adolescents—immunity wanes 5 to 8 yr after vaccination; in 2004, 38% of cases
occurred in children 10 to 19 yr of age; many adolescents have severe symptoms
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| Vaccines: universal immunization is cost-effective; Boostrix approved for patients 10 to 18 yr of age; Adacel approved for
patients 11 to 64 yr of age; both vaccines have good safety profiles and efficacy; recommendations—patients 11 to 18
yr of age (preferably, ages 11-12 yr), if no Td booster within previous 2 yr; acceptable to administer at same time as meningococcal
vaccine; if not given concurrently, space vaccines by ≥1 mo to reduce risk for adverse effects; precautions—
progressive neurologic disease or GBS; contraindications—serious allergic reaction; encephalopathy (after previous
dose) not attributable to other causes; future—replace Td with TDAP booster for adults
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| Questions and answers: cost of Rotarix—see Web site for Centers for Disease Control and Prevention (CDC;
www.cdc.gov); waning immunity after rotavirus vaccine—most severe disease occurs in babies and young children;
infection in older patients unlikely to cause significant problems; rotavirus fatalities—usually occur in children presenting
late in course of disease; TDAP and wound prophylaxis—acceptable to give TDAP in place of Td in older children;
meningitis vaccine in immunocompromised patients—Menactra may replace Menomune; longer duration of immunity
with Menactra; best age for Menactra booster—children receiving booster at 11 to 12 yr of age may require second
booster before entering college; administering booster at 15 yr of age may increase cost-effectiveness; measles vaccine
and autism—summary on CDC web site reviews studies to date; no connection demonstrated between vaccine and autism
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| GERM-PROOF YOUR PATIENTS: BEYOND ANTIBIOTICS AND VACCINES —Harley A. Rotbart, MD, Professor and
Chair, Department of Pediatrics, Pediatric Infectious Diseases, University of Colorado, School of Medicine, and Children’s
Hospital of Denver
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| Hygiene and infection: although importance of hand washing long understood, nosocomial infections remain common;
studies show alcohol-based hand rubs most effective at killing bacteria in hospital setting, followed by antimicrobial
soap, then plain soap; CDC recommendations—health care workers should use soap for visibly soiled hands or alcohol-based
hand rubs for routine decontamination; plain soap—mechanical cleansing uses detergent action; in industrialized
countries, use substantially decreases incidence of diarrhea and vomiting and reduces absenteeism; Canadian study
showed use of cold and flu remedies decreased by 86%; even more effective at reducing illness (eg, diarrhea, skin and
eye infections) in developing countries; improved hand washing practices could save ≈1 million lives worldwide;
triclosan—present in many products; blocks fat synthesis in bacterial cell membranes (ie, true antibiotic); 1% solution
more effective than plain soap at killing bacteria, but no evidence of decreased rate of infections; many products contain
only 0.2% triclosan (no more effective than plain soap); many products have triclosan chemically incorporated into material
(no evidence of efficacy); advice for families—plain soap favored over antibacterial products because of absence of
benefit and potential for increased resistance (not yet demonstrated); liquid soaps preferred over bar soaps (but no studies
have looked at efficacy of liquid soap products); soap dispensers should be cleaned regularly
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| Nutrition: macronutrients—malnutrition greatly increases risk for severe infections; improving nutrition in malnourished
communities dramatically decreases incidence of infectious disease; dietary supplements—almost no regulation by
Food and Drug Administration (FDA); manufacturers required to add disclaimer if product makes claims of specific
health benefits; amino acids—glutamine and arginine supplements beneficial in certain circumstances (eg, premature
babies, adults in intensive care and burn units, elite athletes); no evidence for use in other populations; lysine supplementation
reduces frequency and severity of herpes outbreaks in adults; optimal dose unknown; some adverse effects; not
recommended for use in children; vitamins—in vitamin-deficient patients, vitamin A supplementation reduces morbidity
and mortality from measles, diarrheal illnesses, and, possibly, malaria; no evidence of benefit in vitamin-replete individuals;
vitamin E and vitamin B not shown to boost immune function; limited evidence for immune benefit of vitamin D
supplementation among vitamin-deficient adults; vitamin C supplementation does not reduce frequency of colds nor duration
of cold after onset, but reduces severity and duration if taken prophylactically throughout year or when family
members infected; if supplementation desired, adults should take 500 mg/day, children \>5 yr of age should take 250 mg/
day, and younger children should take 100 to 200 mg/day (liquid preparation); probiotics—present in, eg, yogurt; also
available as supplements; very effective at reducing duration and severity of infectious diarrhea; less evidence for benefit
among patients with antibiotic-associated or traveler’s diarrhea; present in some infant formulas (no data to support use
in healthy babies; associated with reduced risk for necrotizing enterocolitis in premature babies); breast milk—
associated with significant reduction of risk for many infectious diseases; cranberry—supplementation (juice or capsule)
reduces incidence of urinary tract infections and acute and chronic bacteruria in adolescents and young women; tannins
and fructose reduce binding of bacteria to uroepithelial surface; chicken soup—homemade chicken soup (and some
prepared versions) have inhibitory effect on neutrophil chemotaxis, possibly reducing cold symptoms; also rich in cysteine
(which may help treat congestion)
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| Sleep: profound immune benefits seen in laboratory; sleep deprivation in healthy adults decreases antibody response to influenza
vaccine
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| Stress: stress response involves release of adrenaline and immune mediators; acute stress temporarily boosts immunity;
chronic stress increases incidence of illness and infection
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| Cold feet: study—healthy participants with bare feet in ice water for 20 min more likely than controls to develop cold
symptoms after 5 days (30% vs 9%); proposed mechanism—body- or nose-chilling event, in patient with respiratory
virus on board, enhances likelihood of clinical infection
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| Exercise: profound effects in laboratory and in clinic; daily moderate exercise associated with 50% reduction in sick days
and 30% fewer upper respiratory infections (URIs); exhaustive exercise (eg, marathon running) suppresses immunity, increasing
frequency and severity of infections; glutamine supplementation shown to have benefit; exercising when
sick—exercise does not lengthen duration of URI; avoid exercise if “below-the-neck” symptoms occur
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Suggested Reading
Advisory Committee on Immunization Practices Centers for Disease Control and Prevention: Report: decision not to
recommend routine vaccination of all children aged 2-10 years with quadrivalent meningococcal conjugate vaccine
(MCV4). MMWR Morb Mortal Wkly Rep 57:462, 2008; Barr E, Sings HL: Prophylactic PHV vaccines: new interventions
for cancer control. Vaccine Aug 8, 2008 [Epub ahead of print]; Centers for Disease Control and Prevention Advisory
Committee on Immunization Practices: Revised recommendations of the Advisory Committee on Immunization
Practices to vaccinate all persons aged 11-18 years with meningococcal conjugate vaccine. MMWR Morb Mortal Wkly
Rep 56:794, 2007; Cohen F et al: Immune function declines with unemployment and recovers after stressor termination.
Psychosom Med 69:225, 2007; Doron SI et al: Probiotics for prevention of antibiotic-associated diarrhea. J Clin Gastroenterol
42 (Suppl 2):S58, 2008; Guandalini S: Probiotics for children with diarrhea: an update. J Clin Gastroenterol
42(Suppl 2): S53; Haber P et al: Postlicensure monitoring of intussusception after RotaTeq vaccination in the United
States, February 1, 2006, to September 25, 2007. Pediatrics 121:1206, 2008; Kapaskelis AM et al: High prevalence of antibody
titers against Bordatella pertussis in an adult population with prolonged cough. Respir Med Aug 4, 2008 [Epub
ahead of print]; Majde JA, Krueger JM: Links between the innate immune system and sleep. J Allergy Clin Immunol
116:1188, 2005; Rennard BO et al: Chicken soup inhibits neutrophil chemotaxis in vitro. Chest 118:1150, 2000;
Schaffner W: Update on vaccine-preventable diseases: are adults in your community adequately protected? J Fam Pract
57:S1, 2008; Tate JE et al: Trends in intussusception hospitalizations among US infants, 1993-2004: implications for monitoring
the safety of the new rotavirus vaccination program. Pediatrics 121:e1125; Wood N, McIntyre P: Pertussis: review
of epidemiology, diagnosis, management and prevention. Paediatr Respir Rev 9:201, 2008.
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