Varicella
Highly contagious disease due to varicella-zoster virus
Spread by direct contact or the respiratory route
Characteristic pruritic vesicular rash with fever
Complications include pneumonia, encephalitis, and cellulitis
Varicella Epidemiology
Children» 3.5 to 4 million cases each year» generally mild disease with rare
complications Adults
» 5% of all cases occur in those > 15 years» complications much more common
Varicella Vaccine
Varivax licensed April, 1995 A live, attenuated viral vaccine Contraindicated in these situations:
– immunosuppression– pregnancy– receipt of blood products—dose dependent– active untreated TB
Evidence of Varicella Immunity
Born in United States before 1980 Physician documented clinical history of
chicken pox or zoster Laboratory evidence of immunity Two doses of varicella vaccine after first
birthday separated by at least 4 weeks
Evidence of Varicella Immunity for Healthcare Worker
Physician documented clinical history of chicken pox or zoster
Laboratory evidence of immunity Two doses of varicella vaccine after first
birthday separated by at least 4 weeks
Varicella Vaccine Indications
All infants at age 12 months with second dose prior to entering school
– Minimum 3 month interval between doses Second dose recommended for anyone who has received
only one dose Children entering child care facilities or elementary schools
(or evidence of immunity) Assume immune if born in US before 1980 unless healthcare
worker, pregnant woman or immunocompromised
Varicella Vaccine Indications
Routine immunization of all adolescents and adults without evidence of immunity
Prenatal assessment + postpartum immunization
Varicella Vaccine Adverse Effects
Fever Rash
– At injection site: median number of lesions=2– Generalized: median number of lesions=5
Post-Vaccination Herpes Zoster
VAERS rate after vaccination 2.6/100,000 doses distributed
Rate after natural infection for healthy children <20 years 68/100,000 person years
Compare rates with caution– shorter vaccine follow up time– vaccine cases not always caused by vaccine virus
Rotavirus Vaccine
Rotavirus Infection
Half million childhood deaths worldwide
One third of hospitalizations for diarrhea
Incidence similar in developing and developed countries
Impact of Rotavirus in US
MMWR 2006; 55(RR-12)
Rotavirus Vaccines
Live oral vaccine stored refrigerated Two preparations
– Rotateq (Merck) Pentavalent bovine reassortment viruses Three oral doses
– Rotarix (GSK) Attenuated human rotavirus Two oral doses
Recommended at 2, 4, and (6 if Merck product used) months
Vaccine Schedule
First dose between 6 and 14 weeks of age– If inadvertently started, complete series
Second and third doses spaced by 4 to 10 weeks Series must be completed by 8 months of age Initiate or complete series for infants who have
had rotavirus infection
RV and Intussusception
No evidence that risk is different between vaccines
About 45-213 cases per birth cohort Prevents 53,000 hospitalizations and
170,000 ED visits per birth cohort
Vaccine Impact
Dramatic reductions in disease Decreased hospitalization by 42-63% Decreased lost workdays by 87%