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Before availability of varicella vaccine in the United States, an estimated 4 million varicella cases, 11,000-13,500 varicella-related hospitalizations, and 100-150 varicella-related deaths occurred annually. The varicella vaccination program was implemented in the United States in 1996 as a 1-dose routine childhood program. Based on data from two varicella active surveillance sites, the varicella vaccination program led to 90% decline in incidence over the next decade (1). However, because of continued varicella outbreaks, a routine 2-dose schedule (at ages 12-15 months and 4-6 years) was recommended and has been in place since 2006 (2). The declines in incidence (1,3-6) made it feasible for states to implement varicella case-based surveillance and to report varicella data to CDC through the National Notifiable Diseases Surveillance System (NNDSS). State data have become the primary source for monitoring trends in varicella incidence nationally (7). Using NNDSS data, CDC previously reported nationwide declines in varicella incidence of 72% from the end of the 1-dose to the early years of the 2-dose varicella vaccination program (2006-2010) (7). This report updates varicella incidence trends to include the most recent years in the 2-dose varicella vaccination program. Between the period 2005-2006 (before the 2-dose recommendation) and 2013-2014, overall varicella incidence declined 84.6%, with the largest declines reported in children aged 5-9 years (89.3%) and 10-14 years (84.8%). The availability of varicella-specific data varied over time. During the last 2 years examined (2013 and 2014), completeness of reporting of two critical variables monitored by CDC, vaccination status (receipt of at least 1 dose of varicella vaccine) of cases and severity of disease based on number of lesions, were 54.2% and 39.1%, respectively. State and local health departments, in collaboration with CDC, should continue working to improve reporting of cases and completeness of critical varicella-specific variables to better monitor impact of the varicella vaccination program. [ABSTRACT FROM AUTHOR]

Background. The causes of varicella-zoster virus reactivation and herpes zoster (HZ) are largely unknown. We assessed potential risk factors for HZ, the data for which cannot be obtained from the medical sector. Methods. We conducted a matched case-control study. We established active surveillance in Olmsted County, Minnesota to identify HZ occurring among persons age ≥50 years during 2010-2011. Cases were confirmed by medical record review. Herpes zoster-free controls were age- and sex-matched to cases. Risk factor data were obtained by telephone interview. Results. We enrolled 389 HZ case patients and 511 matched controls; the median age was 65 and 66 years, respectively. Herpes zoster was associated with family history of HZ (adjusted odds ratio [aOR] = 1.65); association was highest with first-degree or multiple relatives (aOR = 1.87 and 3.08, respectively). Herpes zoster was also associated with prior HZ episodes (aOR = 1.82), sleep disturbance (aOR = 2.52), depression (aOR = 3.81), and recent weight loss (aOR = 1.95). Stress was a risk factor for HZ (aOR = 2.80), whereas a dose-response relationship was not noted. All associations indicated were statistically significant (P < .05). Herpes zoster was not associated with trauma, smoking, tonsillectomy, diet, or reported exposure to pesticides or herbicides (P > .1). Conclusions. We identified several important risk factors for HZ; however, the key attributable causes of HZ remain unknown. [ABSTRACT FROM AUTHOR]

Background. Vaccine-strain herpes zoster (HZ) can occur after varicella vaccination. This study determined the number and proportion of HZ cases caused by vaccine-strain varicella zoster virus (VZV), assessed the positive predictive value of provider diagnosis of HZ, and computed HZ incidence rates in vaccinated and unvaccinated children.Methods. We used electronic medical records to identify all office visits with an HZ diagnosis for children aged <18 years in a managed care plan. Providers collected skin specimens and completed a questionnaire. Specimens were tested by polymerase chain reaction to identify wild-type or vaccine-strain VZV.Results. From May 2005 to September 2009, we enrolled 322 subjects. VZV was detected in 82% of specimens (84% wild-type, 15% vaccine-strain, 1% possible vaccine–wild-type recombinant). Among the 118 vaccinated subjects, VZV was detected in 70% (52% wild-type). The positive predictive value for provider diagnosis of “definite HZ” was 93% for unvaccinated and 79% for vaccinated children. The incidence of laboratory-confirmed HZ was 48 per 100 000 person-years in vaccinated children (both wild-type and vaccine-strain) and 230 per 100 000 person-years in unvaccinated children (wild-type only).Conclusions. HZ incidence in vaccinated children was 79% lower than in unvaccinated children. Among vaccinated children, half of HZ cases were due to wild-type VZV. [ABSTRACT FROM AUTHOR]

Two live, attenuated varicella zoster virus-containing vaccines are available in the United States for prevention of varicella: 1) a single-antigen varicella vaccine (VARIVAX,® Merck & Co., Inc., Whitehouse Station, New Jersey), which was licensed in the United States in 1995 for use among healthy children aged ≥ 12 months, adolescents, and adults; and 2) a combination measles, mumps, rubella, and varicella vaccine (ProQuad,® Merck & Co., Inc., Whitehouse Station, New Jersey), which was licensed in the United States in 2005 for use among healthy children aged 12 months-12 years. Initial Advisory Committee on Immunization Practices (ACIP) recommendations for prevention of varicella issued in 1995 (CDC. Prevention of varicella: recommendations of the Advisory Committee on Immunization Practices [ACIP]. MMWR 1996;45[No. RR-11]) included routine vaccination of children aged 12-18 months, catch-up vaccination of susceptible children aged 19 months-12 years, and vaccination of susceptible persons who have close contact with persons at high risk for serious complications (e.g., health-care personnel and family contacts of immunocompromised persons). One dose of vaccine was recommended for children aged 12 months-12 years and 2 doses, 4-8 weeks apart, for persons aged ≥ 13 years. In 1999, ACIP updated the recommendations (CDC. Prevention of varicella: updated recommendations of the Advisory Committee on Immunization Practices [ACIP]. MMWR 1999;48[No. RR-6]) to include establishing child care and school entry requirements, use of the vaccine following exposure and for outbreak control, use of the vaccine for certain children infected with human immunodeficiency virus, and vaccination of adolescents and adults at high risk for exposure or transmission. In June 2005 and June 2006, ACIP adopted new recommendations regarding the use of live, attenuated varicella vaccines for prevention of varicella. This report revises, updates, and replaces the 1996 and 1999 ACIP statements for prevention of varicella. The new recommendations include 1) implementation of a routine 2-dose varicella vaccination program for children, with the first dose administered at age 12-15 months and the second dose at age 4-6 years; 2) a second dose catch-up varicella vaccination for children, adolescents, and adults who previously had received 1 dose; 3) routine vaccination of all healthy persons aged ≥ 13 years without evidence of immunity; 4) prenatal assessment and postpartum vaccination; 5) expanding the use of the varicella vaccine for HIV-infected children with age-specific CD4+T lymphocyte percentages of 15%-24% and adolescents and adults with CD4+T lymphocyte counts ≥ 200 cells/µL; and 6) establishing middle school, high school, and college entry vaccination requirements. ACIP also approved criteria for evidence of immunity to varicella. [ABSTRACT FROM AUTHOR]

Background Varicella (VAR) and measles-mumps-rubella (MMR) vaccines are recommended for children at ages 12–15 months and 4–6 years. These are administered as separate MMR and VAR vaccines (MMR+VAR) or as combined measles-mumps-rubella-varicella (MMRV) vaccine. Herpes zoster (HZ), caused by wild-type or vaccine-strain varicella-zoster virus, can occur in children after varicella vaccination. It is unknown whether HZ incidence after varicella vaccination varies by vaccine formulation or simultaneous receipt of MMR. Methods Using data from six integrated health systems, we examined HZ incidence among children who turned 12 months old during 2003–2008 and received varicella and MMR vaccines according to routine recommendations. All HZ cases ≥ 21 days after first varicella vaccination were identified using ICD-9 codes from inpatient, outpatient, emergency room encounters, and claims data, through 2014. HZ incidence was examined by vaccine formulation (MMR+VAR, MMRV, or VAR without same-day MMR) and doses received and compared using incidence rate ratios (IRR). Results Among 199,797 children, we identified 601 HZ cases. Crude HZ incidence after first-dose MMR+VAR (18.6 [95% CI 11.1–29.2] cases/100,000 person-years) was similar to the rate after first-dose MMRV (17.9 [95% CI 10.6–28.3] cases/100,000 person-years), but approximately double the rate among those with first-dose VAR without same-day MMR (7.5 [95% CI 3.1–15.0] cases/100,000 person-years); see Table 1. The IRR for HZ after first-dose MMR+VAR or MMRV, compared with VAR, was 2.5 (95% CI 1.4–4.4; P = 0.002). When examining any first or second dose formulation, crude HZ incidence was lower after the second varicella vaccine dose (13.9 cases/100,000 person-years), than in the period before the second dose (i.e. between first and second doses or after the first dose in children with only one dose; 21.8 cases/100,000 person-years, P < 0.0001). HZ incidence was also lower after two varicella vaccine doses in each of the three first-dose formulation groups. Conclusion HZ incidence among children varied by first-dose varicella vaccine formulation and number of varicella vaccine doses. Regardless of the first-dose varicella vaccine formulation, children who received two vaccine doses had lower HZ incidence after the second dose. Disclosures All authors: No reported disclosures. [ABSTRACT FROM AUTHOR]

The article discusses the U.S. Centers for Disease Control and Prevention's (CDC) updated recommendations for the use of VariZIG, a varicella zoster immune globulin preparation from Cangene Corp. The CDC recommendations replace those issued in 2007 by the Advisory Committee on Immunization Practices (ACIP). The harmonization of the CDC recommendations for VariZIG use with those of the American Academy of Pediatrics (AAP) is also cited.

The article discusses the death of an unvaccinated, previously healthy adolescent due to varicella. Despite being a self-limited disease, varicella can sometimes lead to severe complications and death with increased risk found among infants, adults and immunocompromised persons. The patient presented with fever dyspnea, facial edema and hypotension upon admission and in the course of her stay at the hospital, she developed pneumonia complicated by acute respiratory distress syndrome.

The article presents a case study of an Indian crew member of a cargo vessel off Puerto Rico who died due to varicella pneumonia. Topics covered include symptoms such as a vesicular rash on the face, the coordination of varicella vaccination for the remaining crew members, varicella's transmission by direct contact with vesicle fluid, and the importance of early notification of illness or death to the U.S. Centers for Disease Control Prevention by ships arriving to U.S. ports of entry.

The article reports on the closure of the Pregnancy Registry for Varicella-Zoster Virus (VZV)-Containing Vaccines that was created by Merck & Co. Inc. and the U.S. Centers for Disease Control and Prevention in 1995 to monitor the pregnancy results of women vaccinated with VZV vaccines before or during pregnancy. Topics covered include summaries of reports received by the registry from March 1995 to March 2012, the reasons behind the closure, and plans for monitoring the safety of the vaccines.

Background Two-dose varicella vaccination has been available in Beijing since 2012 in the private sector. We investigated a varicella outbreak in a highly vaccinated elementary school population. Methods A cohort study was carried out and a varicella case was defined as an acute onset of generalized maculopapulovesicular rash without other apparent cause in a student attending the school from March 29 through May 17, 2015. Breakthrough varicella was defined as varicella >42 days after the last vaccine dose among both 1- or 2-dose varicella vaccine recipients. Vaccination information was collected from immunization records; information on prior varicella and clinical presentations was collected by surveying students’ parents. Results Of the 1056 students in the school, 1027 (97.3%) reported no history of varicella. Prior to the outbreak, 98.6% of students had received ≥1 dose of varicella vaccine, and most (63.2%) students received two doses. Twenty varicella cases were identified for an overall attack rate of 2.0%. Half of the cases occurred in the classroom of the index case-patient, a two-dose recipient who was not isolated after symptom onset. Breakthrough varicella accounted for 95% of cases (19/20) with attack rates of 14.3% (1/7), 1.6% (6/362) and 2.0% (13/649) among unvaccinated, one-dose, and two-dose students, respectively. Most case-patients (18/20, 90%) had <50 lesions. No difference in clinical presentations was found between one-dose and two-dose recipients with breakthrough varicella. Conclusion Moderate two-dose varicella vaccine coverage was insufficient to prevent a varicella outbreak. Two-dose recipients with breakthrough varicella are contagious. High two-dose varicella vaccine coverage and timely isolation of cases may be needed for varicella outbreak prevention in the two-dose era. [ABSTRACT FROM AUTHOR]