Rachel Civen

• MD, MPH
• Medical Epidemiologist at County of Los Angeles Public Health

Worksites with on-site operations have experienced coronavirus disease (COVID-19) outbreaks. We analyzed data for 698 nonresidential, nonhealthcare worksite COVID-19 outbreaks investigated in Los Angeles County, California, USA, during March 19, 2020‒September 30, 2020, by using North American Industry Classification System sectors and subsectors....

Although flea-borne rickettsiosis is endemic in Los Angeles County, outbreaks are rare. In the spring of 2015 three human cases of flea-borne rickettsiosis among residents of a mobile home community (MHC) prompted an investigation. Fleas were ubiquitous in common areas due to presence of flea-infested opossums and overabundant outdoor cats and dogs...

The objective of this investigation was to evaluate the effectiveness of monitoring emergency department (ED) chief complaints as an indicator for a Neuro-Invasive (NI) disease outbreak. A retrospective analysis of the West Nile Virus (WNV) community-wide outbreak that occurred in 2004 was performed, matching cases from the county’s vector control...

Study Objective: We conducted a survey of Los Angeles County residents with malaria who traveled abroad to assess prophylaxis use, knowledge of the disease, and differences in awareness by region visited.

Study Objective: To study the relationship between age and duration of symptoms, and overall physical, cognitive, and functional health among WNF cases.

Flea-borne typhus in the United States is distributed in localized areas of California, Hawai'i and Texas. In California, the overwhelming burden of this disease is carried by residents of Los Angeles County (LAC), especially those in downtown Los Angeles, and north and east into the San Gabriel Valley (Wekesa et al. 2016). This disease is classica...

Background: Several clusters of serogroup C meningococcal disease among men who have sex with men (MSM) have been reported in the United States in recent years. The epidemiology and risk of meningococcal disease among MSM is not well-described. Methods: All meningococcal disease cases among men aged 18-64 years reported to the National Notifiabl...

Flea-borne rickettsiosis is the second-most prevalent vector borne disease in the San Gabriel Valley, posing a major public health risk to residents. The San Gabriel Valley Mosquito and Vector Control District began investigating cases of rickettsial disease in neighborhoods within the District in 2014 (Wekesa et al., 2016). These investigations ar...

Background: Changes in herpes zoster (HZ) epidemiology are expected with childhood varicella vaccination. We reported previously that during 2000 to 2006 HZ incidence decreased 55% in children <10 years of age, while among 10- to 19-year olds it increased by 63%. We update the analysis with 4 additional years of data. Methods: Population-based a...

During March 4-August 11, 2016, 25 outbreak-associated cases of meningococcal disease, including two deaths (8% case-fatality ratio), were reported in Southern California. Twenty-four of the cases were caused by serogroup C Neisseria meningitidis (NmC) and one by N. meningitidis with an undetermined serogroup (Figure). On June 24, 2016, in response...

Objectives: We examined overall and incremental effectiveness of 2-dose varicella vaccination in preventing community transmission of varicella among children aged 4 to 18 years in 2 active surveillance sites. One-dose varicella vaccine effectiveness (VE) was examined in those aged 1 to 18 years. Methods: From May 2009 through June 2011, varicel...

Flea-borne typhus is an acute febrile disease caused by Rickettsia typhi and Rickettsia felis transmitted to humans by the bite of Xenopsylla cheopis (rat fleas) or Ctenocephalides felis (cat fleas) found on many vertebrate hosts (Azad et al., 1997). More than 200 human cases of flea-borne typhus occur in the United States every year, but the dise...

Since 2012, three clusters of serogroup C meningococcal disease among men who have sex with men (MSM) have been reported in the United States. During 2012, 13 cases of meningococcal disease among MSM were reported by the New York City Department of Health and Mental Hygiene (1); over a 5-month period during 2012–2013, the Los Angeles County Departm...

Carriers of the pork tapeworm, Taenia solium, are the sole source of cysticercosis, a parasitic tissue infection. When tapeworm eggs excreted by the carrier are ingested, tapeworm larvae can form cysts. When cysts form in the brain, the condition is called neurocysticercosis and can be especially severe. In Los Angeles County an average of 136 coun...

On August 4, 2014, the Acute Communicable Disease Control Program of the Los Angeles County Department of Public Health received a report of three aseptic meningitis cases among football players at a county high school. An investigation was conducted to determine the extent of the outbreak, identify potential exposures, and recommend control measur...

Background/Issue:Each year skilled nursing facilities (SNFs) within Los Angeles County (LAC) are the most frequently reported sites for Gastroenteritis (GE) outbreaks (OBs). In 2011, 34 GE OBs affecting 543 patients and 144 SNF staff reported; 26 Norovirus (NV) was laboratory confirmed. Spring 2012, a Norovirus Outbreak Prevention (NOP) Workgroup c...

: We describe four solid-organ transplant recipients with donor-derived West Nile virus (WNV) infection (encephalitis 3, asymptomatic 1) from a common donor residing in a region of increased WNV activity. All four transplant recipients had molecular evidence of WNV infection in their serum and/or cerebrospinal fluid (CSF) by reverse transcription p...

BACKGROUND: Hospital discharge data are often used to monitoring reportable disease trends; however, few studies have compared this data source to other more tradition surveillance systems. METHODS: We compared annual number of IMD cases, trend and demographic profiles identified in hospital discharge (HD) and reported case (RC) datasets for Cali...

Objective: 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. Methods:...

We identified West Nile virus (WNV) RNA in skin, fat, muscle, tendon, and bone marrow from a deceased donor associated with WNV transmission through solid organ transplantation. WNV could not be cultured from the RNA-positive tissues. Further studies are needed to determine if WNV can be transmitted from postmortem tissues.

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 transferrin...

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...

In Los Angeles, California, USA, 2 epidemics of West Nile virus (WNV) disease have occurred since WNV was recognized in 2003. To assess which measure of risk was most predictive of human cases, we compared 3 measures: the California Mosquito-Borne Virus Surveillance and Response Plan Assessment, the vector index, and the Dynamic Continuous-Area Spa...

Details of data collection, analysis, and calculation of risk for West Nile virus infection by using the California Mosquito-Borne Virus Surveillance and Response Plan Assessment.

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 a...

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. Methods: We examined varicella incidence, age and VV status of case-patients, and number of outbrea...

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/afte...

Background: The Varicella Active Surveillance Project has conducted population-based active surveillance for varicella disease in the AV since 1995. 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 endorse...

Background: LAC DPH has conducted active surveillance on varicella disease since 1995. In 2006, the Advisory Committee on Immunization Practices (ACIP) endorsed the second childhood vaccine dose due to persistent varicella disease in children with childhood varicella vaccination. Objectives: Compare the clinical presentation of varicella disease...

A point-of-dispensing clinic was held to distribute ciprofloxacin prophylaxis when 2 high school students were reported to the health department with invasive meningococcal disease. Of more than 3,100 school staff and students in attendance, 2,861 received prophylaxis. A survey was administered to students 2 weeks postclinic to better understand th...

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 endor...

Babesiosis was reported in a California resident who received a transfusion of blood products collected in the disease-endemic northeastern region of the United States. Babesiosis should be considered year-round in the diagnosis of febrile and afebrile patients with abnormal blood cell counts who have received blood products from disease-endemic ar...

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 ado...

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 rec...

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-wee...

Murine typhus, an acute febrile illness caused by Rickettsia typhi, is distributed worldwide. Mainly transmitted by the fleas of rodents, it is associated with cities and ports where urban rats (Rattus rattus and Rattus norvegicus) are abundant. In the United States, cases are concentrated in suburban areas of Texas and California. Contrary to the...

We describe trends and characteristics of varicella outbreaks identified in an active surveillance site from 1995 to 2005. Cases of varicella were reported to the active surveillance project, and outbreaks were defined retrospectively as ⩾5 varicella cases epidemiologically linked to a common setting that occurred within 1 incubation period. Outbre...

The introduction of universal varicella vaccination in 1995 has substantially reduced varicella-related morbidity and mortality in the United States. However, it remains unclear whether vaccine-induced immunity wanes over time, a condition that may result in increased susceptibility later in life, when the risk of serious complications may be great...

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 cov...

In June 2001, following the report of 4 patients with Serratia marcescens meningitis who received epidural injections of betamethasone compounded at a community pharmacy, we initiated an outbreak investigation. All patients who received injections of betamethasone from the production lot common to the 4 patients were evaluated. A case patient was d...

Background: West Nile Virus (W.N.V.) has recently gained much attention over the past few years as it has spread across the U.S. and caused significant neurologic disease in humans. This study retrospectively looked at patients diagnosed with W.N.V. neurologic disease in four different teaching hospitals in Los Angeles County (L.A.C.), California f...

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...

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...

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...

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...

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 report...

To describe the presentation and management of the first identified case of ocular vaccinia infection associated with the current smallpox vaccination program. Case report. Vaccinia virus was isolated by cell culture of a conjunctival swab. Direct staining with fluorescein isothiocyanate-labeled vaccinia antibody and polymerase chain reaction testi...

We conducted a retrospective study to update the bacteriology of 46 cases of anaerobic empyema that were originally studied between 1976 and 1993 at the Wadsworth Anaerobic Bacteriology Clinical Research Laboratory (Los Angeles). Anaerobic bacteriologic studies were completed for all 46 pleural fluid specimens, and aerobic bacteriologic studies wer...

A retrospective bacteriologic study of anaerobic pleuropulmonary infections diagnosed at the Wadsworth Veterans Affairs Medical Center between 1976 and 1991 was performed. There were 116 specimens from 110 patients. Available strains were reexamined using the latest tests and taxonomic schemes. Pleural fluid was believed to provide the most reliabl...

Peritonsillar abscess is a potentially life-threatening complication of acute tonsillitis. On occasion, peritonsillar abscess can extend to neck spaces and/or to the mediastinum. We describe a case of a patient with a peritonsillar abscess that extended to the neck, producing bilateral retropharyngeal abscesses and myonecrosis of the strap muscles....