Laurene Mascola

Children born to human immunodeficiency virus (HIV)-infected mothers often do not live with a biologic parent because of drug use, illness, or death of the mother. Public health officials need to know the number and proportion of children who will require care by someone other than a biologic parent (alternative care giver). The Pediatric Spectrum of Disease project, conducted in six different geographic regions in the United States, assesses issues specific to HIV in children. Among the information being collected in this study are data regarding the primary care giver. Of 1683 children born to HIV-infected mothers and enrolled through 1990, 55% (937) were living with a biologic parent, 10% (169) with another relative, 28% (455) were in foster care, 3% (55) had been adopted, and 4% (67) lived in group settings or with other care givers. In all locations and for all racial/ethnic groups, children of mothers who used intravenous drugs were more likely to be living with an alternative care giver than were children of mothers who had not used intravenous drugs (odds ratio 4.15). However, there were striking variations by study location (odds ratio range 1.4 to 7.2). The data suggest that maternal drug use may be the most important factor determining whether a child lives with a biologic parent and that there are also regional differences in alternative care placement.

To assess the effects of Haemophilus influenzae vaccination of infants. We evaluated H influenzae type b (Hib) disease rates in Los Angeles County, California (population, 9 million; 1983 through 1992), and in the Southern California Kaiser Health Plan (2.5 million enrollees; 1988 through 1992) during the past decade. Cases were obtained through active and passive disease surveillance in the two populations. The following vaccines were used during the study period (1983 through 1992): (1) Hib polysaccharide vaccine (polyribosyl ribitol phosphate) (used from 1985 through 1987 for children 24 through 60 months of age); (2) Hib polysaccharide-diphtheria toxoid conjugate, Hib polysaccharide CRM197 mutant diphtheria toxoid conjugate vaccine, and Hib polysaccharide outer-membrane protein of group B meningococcus conjugate vaccine in older children (1988 through 1990; ages 15 through 60 months); and (3) Hib polysaccharide CRM197 mutant diphtheria toxoid conjugate vaccine and Hib polysaccharide outer-membrane protein of group B meningococcus conjugate vaccine used in infants (1991 through 1992). Between 1983 and 1988, the Hib disease incidence in Los Angeles County was unchanged (32.7 to 42.5/100,000 person-years in children younger than 5 years). In 1989 through 1990, before Hib conjugate licensure for infant use, Hib disease rates in all age groups declined. After licensure of Hib vaccines for infants in 1990, there was a further fivefold decrease in infants. More dramatic decreases occurred in the better-immunized Kaiser Health Plan children aged 0 through 60 months (53 cases in 1989, only two cases in 1992). The Hib disease has been nearly eradicated in a fully immunized population (Kaiser Health Plan), and significant reductions have also occurred in Los Angeles County.

Using community-based surveillance data for pediatric human immunodeficiency virus (HIV) infection, we examined disease progression using survival analysis among perinatally HIV-infected children and children HIV-infected through a neonatal blood transfusion. As of December 31, 1991, 238 HIV-infected children (classified P-1 or P-2 according to the Centers for Disease Control and Prevention classification system) were identified. Median symptom-free survival time from birth to symptomatic infection (P-2) was different for perinatally acquired (n = 166) and neonatal transfusion-acquired (n = 72) infection (6.4 months vs. 17.8 months, respectively; P < 0.001). Survival after development of symptomatic infection (P-2) did not differ by transmission mode. Survival differences from birth to death were significant at P < 0.05 (75% of perinatally HIV-infected children survived 44 months vs. 71 months for transfusion-associated children). Although survival estimates improved for those receiving antiretroviral treatment, differences by mode were still observed. For perinatally HIV-infected children, mortality was highest in the first year of life (12%). Those remaining symptom-free beyond their first year demonstrated survival experiences similar to those for children with transfusion-associated infection.

Background: LAC has conducted population-based active surveillance for varicella in the Antelope Valley (AV), CA since 1995. From 1995 to 2003, varicella cases in AV have declined by 86%. We studied the trends in varicella outbreaks from 1995-2003. Methods: We performed varicella active surveillance at all reporting sites from 1995-2003. All reported outbreak related varicella cases (verified and probable) were analyzed. Verified cases had completed clinical case interviews and probable cases had demographic information only. A varicella outbreak was defined as 5 or more cases reported from any given school or daycare within one incubation period. We classified breakthrough varicella (BTV) as a macular/papular or papulovesicular rash occurring more than 42 days after receipt of varicella vaccine (VV).Results: Varicella outbreaks declined 91% from 81 in 1995 to 7 in 2003. Of the 81 outbreaks in 1995, 67 (83%) were K-12 schools and 14 (17%) were in daycare. In 2002 -2003 all 15 outbre...

Background: In 2004, 830 West Nile (WN) virus cases were reported in California (CA), 309 in Los Angeles County (LAC). Of those 148 were WN fever cases (WNF). WNF follow-up studies indicate a more severe illness than previously thought. We conducted a follow-up study of LAC-confirmed WNF cases comparing symptom duration and status in younger versus older cases. Methods: WNF definition: 2 of 3 symptoms (febrile illness, fatigue, headache), no clinical neuroinvasive disease or cerebrospinal fluid analysis, and LAC public health or CA Viral and Rickettsial Diseases laboratory-confirmed positive IgM and IgG serology. Sixty randomly selected cases were contacted. A standardized telephone interview was administered after symptom onset. Demographics, duration and symptoms (physical, cognitive and functional) were measured. Data analysis comparing age <50 and > 50 years (SPSS software) using median test (continuous variable) and chi-square or Fisher exact tests (proportions) were perf...

Background: The lifetime risk of HZ is about 30%. Post-herpetic neuralgia (PHN), defined as persisting pain lasting > 90 days after HZ rash onset, is a common complication. In 2006, active surveillance for HZ was conducted for adults > 50 years, the same year HZ vaccine was recommended for persons > 60 years. Methods: 89 sites reported cases bi-weekly. A verified HZ case was defined as a unilateral vesicular rash diagnosed by a medical provider in an AV resident. A standardized case report was completed.If cases reported pain at time of interview, a follow-up call was made 4 months after rash heal date to assess pain duration. HZ incidence, treatment, and presence of pain and PHN were compared among three age groups. Data were analyzed using SAS 9.1. The Chi-squared test was utilized to assess statistical significance. Results: A total of 424 HZ cases were reported; 108 were excluded due to alternate diagnosis or non-resident status. Among the 316 verified HZ cases, 107 (34...

RESULT: A total of 236 HZ cases were reported in AV from 2000-3. The overall HZ incidence for cases <20 years declined over the study period but was not statistically significant. However, there was a statistically significant decline in cases < 10 years from 40 cases ...

The majority of local health departments perform routine restaurant inspections. In Los Angeles County (LAC), California, approximately $10 million/year is spent on restaurant inspections. However, data are limited as to whether or not certain characteristics of restaurants make them more likely to be associated with foodborne incident reports. We used data from the LAC Environmental Health Management Information System (EHMIS), which records the results of all routine restaurant inspections as well as data regarding all consumer-generated foodborne incidents that led to a special restaurant inspection by a sanitarian (investigated foodborne incidents [IFBIs]). We analyzed a cohort of 10,267 restaurants inspected from 1 July 1997 to 15 November 1997. We defined a "case restaurant" as any restaurant with a routine inspection from 1 July 1997 to 15 November 1997 and a subsequent IFBI from 1 July 1997 to 30 June 1998. Noncase restaurants did not have an IFBI from I July 1997 ...

BACKGROUND: The objective of this analysis is to compare the quality of web complaints to those previously only received via telephone. We aim to characterize web based and telephone based complaints by determining the demographics of complainants, the characteristics of the complaints, and evaluate how this new reporting mechanism is impacting the quality of data received. METHODS: We compared web and telephone foodborne illness reports in Los Angeles County (LAC) for one year. The demographics of persons making web complaints and telephone complaints were compared, where race/ethnicity and gender were inferred by name of complainant. In addition, web and telephone complaints were compared using five criteria: timeliness, completeness, severity, cooperation, and public health significance. RESULTS: Web complaints comprised 40.8% of total complaints (n=1588) received in LAC in 2009, yet total reporting was comparable to a year prior to web reporting (2007, n=1700). Latinos/Hispanics...

Background: In light of the pertussis epidemic in CA, evaluating adherence to the Advisory Committee on Immunization Practices (ACIP) recommended vaccine schedule is important. The ACIP recommends that children 4-6 years of age receive a second dose of varicella vaccine (2-VV) and a fifth dose of DTaP, (5-DTaP) unless the 4th dose was given on/after the child’s 4th birthday. In CA, the 2nd VV and 5th DTaP doses are not kindergarten entry requirements. Objectives: * Evaluate vaccination coverage for 2-VV and 5-DTaP doses using school entry vaccine data. * Compare local vaccination coverage with states requiring 2-VV and 5-DTaP doses for “up-to-date” vaccination status for kindergarten entry. Methods: Vaccination history was obtained from kindergarteners within one public school district in AV, CA from mandatory health forms from the 2010-2011 school year. Local coverage rates were compared to published coverage levels taken from 2009-2010 School Entry Immunization Assessment Report d...

A distribution clinic was held to dispense ciprofloxacin (cipro) prophylaxis when two Los Angeles County high school (HS) students were reported to the health department (HD) with invasive meningococcal disease (MD). Despite revealing cases' names to permit assessment of direct case contact, 2861 persons of over 3100 in attendance requested and received cipro. Due to concerns of over-prophylaxis and potential side effects associated with cipro in adolescents, a survey was self-administered to students 2 weeks later to evaluate reasons for clinic attendance and to quantify side effects. Data included reasons for attendance and perception of risk for acquiring MD, rated on a 1 to 5 scale; type of contact with cases; and side effects (SE). Of 2888 students, 1624 completed surveys; 1390 took cipro. Only 3% reported direct contact with the case(s). Headache (17%) and stomachache (10%) were the most common SE. Two students sought medical care for allergic reactions. Students rated the...

BACKGROUND: In 2006, as varicella outbreaks continued to occur in schools with high 1-dose varicella vaccination (VV) coverage, the Advisory Committee on Immunization Practices recommended implementation of a routine 2-dose VV program for children. In 2001, CA adopted single dose school entry requirements for kindergartners and children transferring from out of state schools at all grade levels. We report on further declines in varicella incidence and outbreaks 5 years after routine 2-dose implementation in 2006. METHODS: We examined varicella incidence, age and VV status of case-patients, and number ofoutbreaks from 2006 through 2011 from a varicella active surveillance region, AV, CA. Varicella cases were verified to have had illness with acute onset of diffuse maculopapulovesicular rash without another known cause. On a biweekly basis, over 100 community-based sites submitted varicella case reports or documentation of no cases. Two HMOs and one emergency room reported electronica...

Background: Since the introduction of the varicella vaccine, LAC DPH has conducted population- based active surveillance for varicella disease in AV. From 1995 to 2005, varicella incidence rates (VIR) declined by 90% and single dose vaccine coverage was 90% for LAC children <24 months. In 2006, the Advisory Committee on Immunization Practices endorsed a second dose of varicella vaccine for children 4-6 years old due to increasing varicella cases after primary vaccination. We compared the VIR and clinical presentation of verified varicella cases from 2005- 2006 (1st dose usage) and 2007-2008 (adoption of 2nd dose). Methods: Varicella cases had illness with acute onset of diffuse maculopapulovesicular rash without other cause. Verified cases had complete case reports and resided within AV. VIR were calculated using 2005-08 US AV census data. The Chi Square test was used to assess statistical significance. Results: Both overall and age- specific VIR for groups <15 years declined ...

Background: In 2004, 137 cases of neuroinvasive disease (NID) and 149 West Nile Fever (WNF) cases were laboratory confirmed in LAC. Of these, only 11 (4%) were in children less than 18 years. Information regarding pediatric clinical presentation of WNV is limited. We describe a population-based case series of 11 WNV-infected children. Methods: Case finding was accomplished through county-wide physician and infection control professional notification in May 2004 to report all cases of encephalitis and meningitis and to consider WNV testing for encephalitis, viral meningitis, acute flaccid paralysis (AFP), and WNF. In July, the Health Officer made WNV infections reportable. All reported WNV cases were serologically confirmed by either the LAC PHL or the CA Viral and Rickettsial Diseases Laboratory (VRDL). Standard CDC case definitions were used to classify cases as NID or WNF. Results: Eleven pediatric WNV infections were confirmed with onsets from July 29 to September 27, 2004. Eight...

Nationally, over 8 million people travel abroad every year to malaria endemic regions such as Asia (5 million), Latin America (3 million) and Africa (500K)1. In 2004, there were 1324 cases of malaria reported in the U.S., with 51 cases (4%) reported to the Los Angeles County (LAC) Health Department. All LAC reported malaria infections were acquired outside the U.S.; 34 (66%) traveled abroad and 17 (33%) were among recent immigrants. We conducted a survey of LAC residents with malaria who traveled abroad to assess prophylaxis use, knowledge of the disease, and differences in awareness by region visited.

Background: Neisseria meningitidis(NM) is an important cause of meningitis and septicemia. Most IMD is caused by serogroups (SG) A, B, C, Y and W- 135, only B is not preventable by US vaccines. Vaccines have been recommended for high risk groups since 1981 and meningococcal conjugate vaccine (MCV4) has been endorsed for adolescents since 2005. LAC MCV4 coverage approached 60% in 2009. Suspected IMD cases are reportable to public health departments. We describe LAC surveillance data from 1995-2009 to assess changes in IMD incidence and SG distribution. Methods: A confirmed IMD case had NM cultured from sterile sites. Age and race/ethnicity were obtained from IMD reports. Confirmed cases with onset from 1995-2009 were included in the analysis. NM isolates were serotyped by slide agglutination test. Annual and 5-yr group incidence rates (IR) (onsets from 1995-1999, 2000-2004, and 2005-2009) were calculated with census estimates. Results: Annual IR declined by 60% from 0.5 to 0.2 cases/...

BACKGROUND: CRKP is an emerging multidrug resistant pathogen and the most frequently isolated species of carbapenem-resistant Enterobacteriaceae in the United States. CRKP has caused large nosocomial outbreaks and become endemic in certain hospitals on the East Coast, subsequently spreading across the United States. CRKP were thought to be rare and sporadic in Los Angeles County (LAC); however actual prevalence in LAC is unknown. Because CRKP could give rise to pan-resistant Klebsiella pneumoniae(KP), we initiated community-wide passive surveillance. METHODS: LAC declared CRKP a laboratory-reportable disease from June 1 2010 – July 31 2012. Laboratory directors of all 102 LAC acute care hospitals (ACHs) and 5 reference laboratories were instructed to submit susceptibility testing results for patients who test positive for CRKP. CRKP was defined as a KP isolate with resistance to carbapenems by Clinical and Laboratory Standards Institute criteria. CRKP isolates from the same patient ...

BACKGROUND: Developed in 2001 by Los Angeles County Department of Medical Examiner-Coroner (DME-C) and Los Angeles County Department of Public Health (LAC-DPH), the Unusual Death Surveillance System (UDSS) functions to identify potential acts of bioterrorism and emerging infectious disease events in LAC. DME-C provides a 42-variable dataset for coroner cases on a daily basis, and includes all cases reported in the previous 24 hours. The dataset contains information on demographics, the circumstances of the death, as well as description of the death scene. We assessed the effect of system automation by reviewing data from two time periods. METHODS: Previously coroner reports were manually queried by DME-C staff and emailed to LAC-DPH. Automation of data exchange, completed in July 2012, consisted of querying data directly from the DME-C server and placing in a secure FTP folder location. A daily program that imported data into SAS and ran an algorithm performing text string searches ...

BACKGROUND: Coccidioidomycosis (Valley Fever), endemic to southern California, is an infection resulting from the inhalation of airborne spores of Coccidioides immitis or Coccidioides posadasii. Coccidioidomycosis has been a reportable disease in California since 1928, and is reportable within seven calendar days. We evaluated the Los Angeles County (LAC) Acute Communicable Disease Control Program (ACDC) coccidioidomycosis surveillance system. METHODS: CDC’s Updated Guidelines for Evaluating Public Health Surveillance Systems were used to evaluate LAC’s coccidioidomycosis surveillance system from 1996 to 2013. The performance of the system as it relates to flexibility, stability, data quality, and timeliness was evaluated. We reviewed ability for the system to adapt to disease specific changes. LAC follows the current Council for State and Territorial Epidemiologists coccidioidomycosis case definition requiring clinical presentation and a single serology unlike the 1996 case definit...

To describe the progression of human immunodeficiency virus (HIV) disease through clinical stages from birth to death among a large number of perinatally infected children. The Pediatric Spectrum of Disease (PSD) project, coordinated by the Centers for Disease Control and Prevention (CDC), has conducted active surveillance for HIV disease since 1988 in seven geographic regions. PSD data are collected from medical and social service records every 6 months through practitioners at each participating hospital clinic. We analyzed data from perinatally HIV-infected children born between 1982 and 1993. The natural history of HIV disease was divided into five progressive stages using the clinical categories in the CDC 1994 pediatric HIV classification system: stage N, no signs or symptoms; stage A, mild signs or symptoms; stage B, moderate signs or symptoms; stage C, severe signs or symptoms; and stage D, death. A five-stage Markov model was fitted to the PSD data. To compare the estimates...

Background: Methicillin-resistant Staphylococcus aureus (MRSA) outbreaks have been increasingly reported in correctional facilities, IDUs, athletic teams, and ethnic minorities but little has been reported on hospitalization rates. The Los Angeles County Jail is the largest jail in the US (>20,000 inmates); the largest outbreak of MRSA in the US (N=934) was reported there in 2002. All inmates are hospitalized at one hospital (Hospital A). Objective: To assess characteristics and morbidity among inmates hospitalized due to MRSA. Methodology: Charts review of inmates hospitalized with MRSA in Hospital A in 2002. Cases were identified by: (1) ICD-9 queries (all S. aureus diagnosis in 2002) of Hospital A database, (2) Hospital A lab list (all MRSA+ cultures in 2002), and (3) inpatient medical records. Results: Eighty-one of 934 inmates (8.7%) required hospitalization for MRSA in 2002. The male/female ratio was 5.8 (male [n=69, 85.2%]; female [n=12, 14.8%]); ages ranged from 19–77 yea...

The purpose of this study was to assess the validity of self-reported history for varicella disease relative to serological evidence of varicella immunity in pregnant women attending antenatal care at clinics located in two diverse geographical locations in the U.S. (Antelope Valley, California, and Philadelphia) with high varicella vaccination coverage. Pregnant women attending prenatal care appointments who needed blood drawn as part of their routine care were eligible to participate. Self-reported varicella disease history was obtained via questionnaire. Varicella serostatus was determined using a whole-cell enzyme-linked immunosorbent assay to test for varicella zoster virus-specific immunoglobulin G (VZV IgG) antibodies. Of the 309 study participants from Antelope Valley and the 528 participants from Philadelphia who self-reported having had chickenpox disease, 308 (99.7%; 95% confidence interval [CI]: 98.2, 100) and 517 (97.9%; 95% CI: 96.3, 99.0), respectively, had serologica...

Persons infected with human immunodeficiency virus (HIV) are at greater risk of infection with Listeria monocytogenes (LM) than the general population. We quantify the risk of listeriosis in persons with acquired immune deficiency syndrome (AIDS) and HIV infection in Los Angeles County (LAC) and report the LM serotype distribution among HIV-infected patients with listeriosis. Active surveillance for listeriosis was performed in LAC during most of the period from 1985 through 1992. Thirty-four (10%) of 351 nonperinatal cases of listeriosis reported in LAC from 1985 through 1992 were in HIV-infected persons, 25 of whom met the 1987 AIDS case definition. The incidence of listeriosis was 95.8 and 8.8 cases per 100,000 person-years among persons with AIDS and all HIV-infected persons, respectively, but only 1.0 case per 100,000 person-years in the total population. Excluding cases from a 1985 listeriosis epidemic associated with consumption of contaminated Mexican-style cheese, 11 (65%) of 17 HIV-infected persons with available isolates were infected with LM serotype 1/2b, whereas only 64 (31%) of 208 other persons with listeriosis and available isolates were infected with LM serotype 1/2b (odds ratio = 4.1; 95% confidence interval = 1.3-14.1). LM serogroup 1/2b may have been more common among HIV-infected persons in LAC than among other persons with listeriosis because of differences in diet or sexual practices, or to chance alone. Persons with HIV-infection, especially those with AIDS, should be educated in avoiding foods at high risk of listerial contamination, such as soft cheeses, foods sold from delicatessen counters, and undercooked chicken.

An outbreak of community-associated methicillin-resistant Staphylococcus aureus (MRSA) skin and soft tissue infection (SSTI) occurred in a college football team from August to September 2003. Eleven case-players were identified, and boils were the most common sign. Linemen had the highest attack rate (18%). Among 99 (93% of team) players with cultured specimens, 8 (8%) had positive MRSA nasal cultures. All available case-players' MRSA isolates characterized had the community-associated pulsed-field type USA300. A case-control study found that sharing bars of soap and having preexisting cuts or abrasions were associated with infection. A carrier-control study found that having a locker near a teammate with an SSTI, sharing towels, and living on campus were associated with nasal carriage. Successful outbreak control measures included daily hexachlorophene showers and hygiene education.

Efforts to reduce bacterial contamination in platelets (PLTs) have led to implementation of tests for bacterial detection before product release. Although relatively rare as a human pathogen, Listeria monocytogenes often causes serious illness and has a case-fatality rate of 20 percent. PLTs from an asymptomatic 58- year-old Hispanic male with a long history of PLT donation were culture-positive for the presence of L. monocytogenes. The pulsed-field gel electrophoresis (PFGE) pattern of the isolate matched two other L. monocytogenes isolates in the CDC National PulseNet database. Public health investigation found no evidence that the other two isolates were epidemiologically related to the PLT donor, who remained asymptomatic. A cluster of listeriosis cases was detected by PFGE but the significance is unknown. Organisms of public health significance should be reported to health departments. Better surveillance and reporting are needed in the efforts to improve blood product safety.

To describe the epidemiology and clinical characteristics of varicella reinfections reported to a surveillance project. We investigated varicella cases reported to a surveillance project between January 1, 1995, and December 31, 1999--with more extensive investigation of cases reporting previous varicella with onset between January 1, 1998, and September 30, 1998--to provide a more detailed description of first and second varicella infections. A simple decision tree was used to assess the likelihood that reported first and second infections were varicella. Among varicella cases reported to the surveillance project, 4.5% of cases in 1995 and 13.3% of cases in 1999 reported previous varicella. More than 95% of first infections were physician diagnosed, epidemiologically linked to another case, or had a rash description consistent with varicella; the same was true for reported second infections. People who reported reinfections were generally healthy. There was a family history of repeat infections in 45% of people who reported reinfections. Clinical varicella reinfections may occur more commonly than previously thought. Additional studies of the predictive value of a positive varicella history and laboratory studies of reported reinfections are indicated to guide varicella vaccination policy.

In 1998, 3 years after vaccine licensure, child care centers (CCC) in Los Angeles County continued to report varicella outbreaks. We investigated outbreaks at 2 CCCs to determine the cause for them, such as low vaccination coverage levels or unexpected low vaccine effectiveness. We collected information on past history of varicella, illness during the outbreak, and prior varicella vaccination among CCC attendees. We found that CCC "H" had a vaccination coverage of 87% (34/39) compared with 30% (6/20) in CCC "L." The overall attack rate was lower in CCC "H" (31%) than in "L" (61%; P value =.03). Vaccine effectiveness for any varicella was 71% in "H" and 100% in "L." Vaccinated children with varicella had milder disease than unvaccinated. In conclusion, we found varicella outbreaks in CCCs with both high and low vaccination coverage. Vaccine effectiveness was within the range predicted by the literature. Vaccination led to a lower attack rate in the highly vaccinated CCC and appeared to protect from severe disease.

One-dose varicella vaccination for children was introduced in the United States in 1995. In 2006, a second dose was recommended to further decrease varicella disease and outbreaks. We describe the impact of the 2-dose vaccination program on varicella incidence, severity, and outbreaks in 2 varicella active surveillance areas. We examined varicella incidence rates and disease characteristics in Antelope Valley (AV), CA, and West Philadelphia, PA, and varicella outbreak characteristics in AV during 1995-2010. In 2010, varicella incidence was 0.3 cases per 1000 population in AV and 0.1 cases per 1000 population in West Philadelphia: 76% and 67% declines, respectively, since 2006 and 98% declines in both sites since 1995; incidence declined in all age groups during 2006-2010. From 2006-2010, 61.7% of case patients in both surveillance areas had been vaccinated with 1 dose of varicella vaccine and 7.5% with 2 doses. Most vaccinated case patients had <50 lesions with no statistically significant differences among 1- and 2-dose cases (62.8% and 70.3%, respectively). Varicella-related hospitalizations during 2006-2010 declined >40% compared with 2002-2005 and >85% compared with 1995-1998. Twelve varicella outbreaks occurred in AV during 2007-2010, compared with 47 during 2003-2006 and 236 during 1995-1998 (P < .01). Varicella incidence, hospitalizations, and outbreaks in 2 active surveillance areas declined substantially during the first 5 years of the 2-dose varicella vaccination program. Declines in incidence across all ages, including infants who are not eligible for varicella vaccination, and adults, in whom vaccination levels are low, provide evidence of the benefit of high levels of immunity in the population.

To describe varicella disease in infants since implementation of the varicella vaccination program in the United States. From 1995 to 2008, demographic, clinical, and epidemiologic data on cases of varicella in infants were collected prospectively through a community-based active surveillance project. We examined disease patterns for infants in 2 age groups: 0 to 5 and 6 to 11 months. Infant varicella disease incidence declined 89.7% from 1995 to 2008. Infants aged 0 to 5 months had milder clinical disease than those aged 6 to 11 months: ≥50 lesions, 49% vs 58% (P = .038); fever (body temperature > 38°C), 12% vs 21% (P = .014); and varicella-related complications, 6% vs 14% (P = .009), respectively. Age was an independent predictor of the occurrence of complications. The varicella vaccination program has resulted in substantial indirect benefits for infants, who are not eligible for vaccination. Presence of maternal varicella-zoster virus antibodies might explain attenuated disease in very young infants likely born to mothers with history of varicella. Although varicella disease incidence has declined, exposure to varicella-zoster virus continues to occur. Improving varicella vaccination coverage in all age groups will further reduce the risk of varicella exposure and protect those not eligible for varicella vaccination.

Neisseria meningitidis is a leading cause of bacterial meningitis and septicemia in the United States. Approximately 10-15% of meningococcal patients died despite antimicrobial therapies. We used vital records to assess meningococcal disease mortality in the United States during 1990-2002. Meningococcal cases were defined as reported deaths with recorded International Classification of Diseases, 9th revision (ICD-9) codes 036.0-036.9 or ICD-10 codes A39.0-A39.9. Denominator data were obtained from population estimates published by the U.S. Census Bureau. We analyzed the effects of age, sex, race/ethnicity and season of the year on meningococcal disease mortality. We identified 3335 meningococcal deaths. Both the crude and age-adjusted mortality rates were 0.10 death per 100,000 population per year (95% confidence interval, 0.09-0.10). Fifty-eight percent of deaths occurred among persons younger than 25 years old. Mortality was elevated in infants, young adults (15-24 years old), and older adults (older than 74 years old). Mortality rates in African-Americans were 1.45 and 3.32 times higher than mortality rates in whites and Asians/Pacific Islanders, respectively. Mortality caused by meningococcal disease rose in winter months and declined during the summer. Observed mortality rates increased from 1990 to 1997 and decreased from 1997 to 2002. Meningococcal disease continues to be an important, vaccine-preventable cause of death in the United States. Vaccination and other disease prevention efforts should be augmented for higher risk groups. Meningococcal mortality data can be used to assess the effectiveness of these efforts.

In 2004, Los Angeles County confirmed 11 cases of symptomatic West Nile virus (WNV) infections in children younger than 18 years of age. Eight had WNV fever, 2 had meningitis and 1 had encephalitis. Fever, rash, nausea and vomiting were the most prominent symptoms at presentation; median duration of illness was 7 days. Clinicians should be aware of the risk of WNV illness, confirm this diagnosis and report suspected WNV cases to their local health department.

Methicillin-resistant Staphylococcus aureus (MRSA) has become increasingly common in neonatal intensive care units and can lead to severe outcomes. Baby C, of a set of quadruplets, died of MRSA sepsis. The surviving siblings were colonized with MRSA. Expressed breast milk was fed to all infants; tested breast milk samples were all MRSA-positive. Pulsed field gel electrophoresis results of isolates from the infants and breast milk were indistinguishable.

Using community-based surveillance data for pediatric human immunodeficiency virus (HIV) infection, we examined disease progression using survival analysis among perinatally HIV-infected children and children HIV-infected through a neonatal blood transfusion. As of December 31, 1991, 238 HIV-infected children (classified P-1 or P-2 according to the Centers for Disease Control and Prevention classification system) were identified. Median symptom-free survival time from birth to symptomatic infection (P-2) was different for perinatally acquired (n = 166) and neonatal transfusion-acquired (n = 72) infection (6.4 months vs. 17.8 months, respectively; P < 0.001). Survival after development of symptomatic infection (P-2) did not differ by transmission mode. Survival differences from birth to death were significant at P < 0.05 (75% of perinatally HIV-infected children survived 44 months vs. 71 months for transfusion-associated children). Although survival estimates improved for those receiving antiretroviral treatment, differences by mode were still observed. For perinatally HIV-infected children, mortality was highest in the first year of life (12%). Those remaining symptom-free beyond their first year demonstrated survival experiences similar to those for children with transfusion-associated infection.

The varicella-zoster virus (VZV) vaccine strain may reactivate to cause herpes zoster. Limited data suggest that the risk of herpes zoster in vaccinated children could be lower than in children with naturally acquired varicella. We examine incidence trends, risk and epidemiologic and clinical features of herpes zoster disease among children and adolescents by vaccination status. Population-based active surveillance was conducted among <20 years old residents in Antelope Valley, California, from 2000 through 2006. Structured telephone interviews collected demographic, varicella vaccination and disease histories, and clinical information. From 2000 to 2006, the incidence of herpes zoster among children<10 years of age declined by 55%, from 42 cases reported in 2000 (74.8/100,000 persons; 95% confidence interval [95% CI]: 55.3-101.2) to 18 reported in 2006 (33.3/100,000; 95% CI: 20.9-52.8; P<0.001). During the same period, the incidence of herpes zoster among 10- to 19-year-olds increased by 63%, from 35 cases reported in 2000 (59.5/100,000 persons; 95% CI: 42.7-82.9) to 64 reported in 2006 (96.7/100,000; 95% CI: 75.7-123.6; P<0.02). Among children aged<10 years, those with a history of varicella vaccination had a 4 to 12 times lower risk for developing herpes zoster compared with children with history of varicella disease. Varicella vaccine substantially decreases the risk of herpes zoster among vaccinated children and its widespread use will likely reduce overall herpes zoster burden in the United States. The increase in herpes zoster incidence among 10- to 19-year-olds could not be confidently explained and needs to be confirmed from other data sources.