Search

Background: Accurate, complete, timely data were essential to effective contact tracing for COVID-19. Maryland Department of Health partnered with Maryland's designated health information exchange, Chesapeake Regional Information System for Our Patients (CRISP), to establish data enhancement processes that provided the foundation for Maryland's successful contact tracing program., Methods: Hourly, electronic positive COVID-19 test results were routed through CRISP to the contact tracing data platform. The CRISP matched reports against its master patient index to enhance the record with demographic, locating, fatality, vaccination, and hospitalization data. Records were deduplicated and flagged if associated with a congregate setting, select state universities, or recent international travel. χ 2 Tests were used to assess if CRISP-added phone numbers resulted in better contact tracing outcomes., Results: During June 15, 2020, to September 1, 2021, CRISP pushed 531,094 records to the state's contact tracing data platform within an hour of receipt; of those eligible for investigation, 99% had a phone number. The CRISP matched 521,731 (98%) records to their master patient index, allowing for deduplication and enrichment. The CRISP flagged 15,615 cases in congregate settings and 3304 cases as university students; these records were immediately routed for outbreak investigation. Records with an added phone number were significantly more likely to be successfully reached compared with cases with no added phone number ( P = 0.01)., Conclusions: The CRISP enhanced COVID-19 electronic laboratory reports with a near-instant impact on public health actions. The partnership and data processing workflows can serve as a blueprint for data modernization in public health agencies across the United States., Competing Interests: Conflict of Interest and Sources of Funding: None declared., (Copyright © 2022 Written work prepared by employees of the Federal Government as part of their official duties is, under the U.S. Copyright Act, a “work of the United States Government” for which copyright protection under Title 17 of the United States Code is not available. As such, copyright does not extend to the contributions of employees of the Federal Government.)

Among 9048 people infected with SARS-CoV-2 between January and May 2021 in Maryland, in regression-adjusted analysis, SARS-CoV-2 viruses carrying the spike protein mutation E484K were disproportionately prevalent among persons infected after full vaccination against COVID-19 compared with infected persons who were not fully vaccinated (aOR, 1.96; 95% CI: 1.36-2.83)., (Published by Oxford University Press for the Infectious Diseases Society of America 2021.)

Approximately 476,000 cases of Lyme disease are diagnosed in the United States annually, yet comprehensive economic evaluations are lacking. In a prospective study among reported cases in Lyme disease-endemic states, we estimated the total patient cost and total societal cost of the disease. In addition, we evaluated disease and demographic factors associated with total societal cost. Participants had a mean patient cost of ≈$1,200 (median $240) and a mean societal cost of ≈$2,000 (median $700). Patients with confirmed disseminated disease or probable disease had approximately double the societal cost of those with confirmed localized disease. The annual, aggregate cost of diagnosed Lyme disease could be $345-968 million (2016 US dollars) to US society. Our findings emphasize the importance of effective prevention and early diagnosis to reduce illness and associated costs. These results can be used in cost-effectiveness analyses of current and future prevention methods, such as a vaccine.

Entomological measures have long served as proxies for human risk of Lyme disease (LD) and other tickborne diseases (TBDs) in endemic areas of the United States, despite conflicting results regarding the correlation between these measures and human disease outcomes. Using data from a previous TBD intervention study in Connecticut, Maryland and New York, we evaluated whether human-tick encounters can serve as an accurate proxy for risk of TBDs in areas where LD and other Ixodes scapularis-transmitted infections are common. Among 2,590 households consisting of 4,210 individuals, experiencing a tick encounter was associated with an increased risk of both self-reported (RR = 3.17, 95% CI: 2.05, 4.91) and verified TBD (RR = 2.60, 95% CI: 1.39, 4.84) at the household level. Household characteristics associated with experiencing any tick encounter were residence in Connecticut (aOR = 1.86, 95% CI: 1.38, 2.51) or New York (aOR = 1.66, 95% CI: 1.25, 2.22), head of household having a graduate level education (aOR = 1.46, 95% CI: 1.04, 2.08), owning a pet (aOR = 1.80, 95% CI: 1.46, 2.23) and a property size of 2 acres or larger (aOR = 2.30, 95% CI: 1.42, 3.70). Results for individual characteristics were similar to those for households. Future prevention studies in LD endemic areas should consider using human-tick encounters as a robust proxy for TBD risk., (© 2021 Wiley-VCH GmbH. This article has been contributed to by US Government employees and their work is in the public domain in the USA.)

In late January 2021, a clinical laboratory notified the Maryland Department of Health (MDH) that the SARS-CoV-2 variant of concern B.1.351 had been identified in a specimen collected from a Maryland resident with COVID-19 (1). The SARS-CoV-2 B.1.351 lineage was first identified in South Africa (2) and might be neutralized less effectively by antibodies produced after vaccination or natural infection with other strains (3-6). To limit SARS-CoV-2 chains of transmission associated with this index patient, MDH used contact tracing to identify the source of infection and any linked infections among other persons. The investigation identified two linked clusters of SARS-CoV-2 infection that included 17 patients. Three additional specimens from these clusters were sequenced; all three had the B.1.351 variant and all sequences were closely related to the sequence from the index patient's specimen. Among the 17 patients identified, none reported recent international travel or contact with international travelers. Two patients, including the index patient, had received the first of a 2-dose COVID-19 vaccination series in the 2 weeks before their likely exposure; one additional patient had a confirmed SARS-CoV-2 infection 5 months before exposure. Two patients were hospitalized with COVID-19, and one died. These first identified linked clusters of B.1.351 infections in the United States with no apparent link to international travel highlight the importance of expanding the scope and volume of genetic surveillance programs to identify variants, completing contact investigations for SARS-CoV-2 infections, and using universal prevention strategies, including vaccination, masking, and physical distancing, to control the spread of variants of concern., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. No potential conflicts of interest were disclosed.

We conducted a cross-sectional study to evaluate associations between pet characteristics and behaviours and risk of tick encounters among pets and pet owners. We defined a tick encounter as ticks found crawling on or attached to a pet or pet owner. Information about pet characteristics, interactions between owners and pets, and tick encounters were captured through an online survey. Associations were evaluated using univariate and multivariable analyses. In univariate analysis, walking dogs only on pavement reduced risk of tick encounter among owners (prevalence ratio (PR) = 0.51, 95% confidence interval (CI): 0.30, 0.84). Having a dog or cat that hunted small animals increased risk of tick encounter among owners (PR = 1.66, 95% CI: 1.30, 2.13; PR = 1.57, 95% CI: 1.05, 2.34, respectively). No direct interactions between owners and pets (e.g., pets sleeping on owners' beds) were associated with increased risk of tick encounters among owners. In multivariable analysis among dog owners, having a pet with a tick encounter within the last six months was associated with increased risk of owner tick encounter (adjusted odds ratio (aOR) = 4.17, 95% CI: 2.94, 5.92); in addition, having a dog that hunts small animals was associated with increased risk of owner tick encounter (aOR = 1.97, 95% CI: 1.25, 3.11). These results suggest that the location of pet-owner interactions may be more important than the type of interactions. Pet owners should avoid tick habitat with pets; when that is not possible, proper use of tick preventive products for pets, wearing repellents by owners and conducting tick checks for both pets and owners is critical for prevention of tick encounters and tick-borne disease., (© 2020 Wiley-VCH GmbH.)

Tickborne diseases (TBDs) such as Lyme disease (LD), babesiosis, ehrlichiosis and Rocky Mountain spotted fever cause substantial morbidity and even mortality in the USA. Data indicate that Hispanic populations may be at greater risk for occupational exposure to ticks and disseminated LD; however, information on knowledge and practices of Hispanic populations regarding TBDs is limited. We surveyed 153 Hispanic and 153 non-Hispanic residents of Maryland and Virginia to assess awareness of TBDs, prevention practices and risk of tick encounters. Hispanic respondents were less likely than non-Hispanics to report familiarity with LD symptoms (21% vs. 53%, p < 0.001) and correctly identify ticks as vectors of LD (40% vs. 85%, p < 0.001). Although there was no significant difference in overall proportion of respondents who routinely take one or more preventive measures to prevent tick bites (59% vs. 61%, p = 0.65), Hispanics were more likely to report showering after coming indoors (36% vs. 25%, p = 0.04) but less likely to conduct daily tick checks compared with non-Hispanics (17% vs. 35%, p < 0.001). History of tick bite or finding a tick crawling on oneself or a household member in the past year did not significantly differ between Hispanics and non-Hispanics (19% vs. 24%, p = 0.26). Notably, after controlling for Hispanic/non-Hispanic ethnicity, primary language (English vs. Spanish) was a significant predictor of whether an individual had knowledge of LD symptoms, correctly identified ticks as vectors for LD and performed daily tick checks. These results provide guidance for future development of more targeted and effective TBD prevention education for both Hispanic and non-Hispanic communities., (© Published 2019. This article is a U.S. Government work and is in the public domain in the USA.)

Rabies is a zoonotic disease that poses a serious public health risk. To facilitate pet owner compliance with statewide mandatory animal rabies immunization requirements, Maryland statute requires Maryland's local health departments to conduct low-cost animal rabies vaccination clinics at least twice per year. We describe the outputs of these public low-cost clinics by documenting the number of animals vaccinated, number of clinics held annually, and cost per vaccine to pet owners for the years 2015-2016. These data are compared with clinic data from 2006 to 2008, providing insight into changes that have occurred in the decade interval between the surveys and consequently informing future clinic policies and procedures. The Maryland low-cost rabies clinic model allows for the vaccination of roughly 20,000 pet animals per year, representing ∼1% of the Maryland pet population, and can be adopted by other states to allow for more comprehensive rabies vaccination coverage in other regions of the country.

HIV nucleotide sequences generated through routine drug resistance testing (DRT) and reported to Maryland's Molecular HIV Surveillance system are most effective for elucidating transmission patterns and identifying outbreaks if DRT is ordered promptly and sequences are reported completely. Among reported cases of HIV infection newly diagnosed during 2011-2013 in Maryland residents aged ≥13 years, we assessed sequence ascertainment completeness. To better understand which populations were most likely to have a sequence, we examined associations between sequence ascertainment and clinical and demographic characteristics. During 2011-2013, 4423 new HIV infection diagnoses were reported; sequences were ascertained for 1282 (29.0%). Among 3267 cases with complete data, odds for having a sequence ascertained were highest for cases in persons living inside Maryland's Central Region with initial CD4 counts ≤500 cells/mm 3 (adjusted odds ratio [aOR] 2.4, 95% confidence interval [CI] 1.9-3.1). Sequence ascertainment did not vary significantly by patient age, sex, race/ethnicity or HIV transmission category. Educational interventions, policy changes and improved processes to increase timely DRT and subsequent sequence reporting with a focus on testing at entry to care, particularly for those with higher CD4 counts and those living outside the Central Region, might improve ascertainment completeness.

On September 17, 2017, the Maryland Department of Agriculture (MDA) was notified by fair and 4-H officials of ill swine at agricultural fair A, held September 14-17. That day, investigation of the 107 swine at fair A revealed five swine with fever and signs of upper respiratory tract illness. All five respiratory specimens collected from these swine tested positive for influenza A virus at the MDA Animal Health Laboratory, and influenza A(H3N2) virus was confirmed in all specimens by the U.S. Department of Agriculture National Veterinary Services Laboratory (NVSL). On September 18, MDA was notified by fair and 4-H officials that swine exhibitors were also ill. MDA alerted the Maryland Department of Health (MDH). A joint investigation with MDH and the local health department was started and later broadened to Maryland agricultural fairs B (September 13-17) and C (September 15-23). In total, 76 persons underwent testing for variant influenza, and influenza A(H3N2) variant (A(H3N2)v) virus infection was identified in 40 patients with exposure to swine at these fairs (Figure), including 30 (75%) who had more than one characteristic putting them at high risk for serious influenza complications; 24 (60%) of these were children aged <5 years. Twenty-six (65%) patients reported direct contact with swine (i.e., touching swine or swine enclosure), but 14 (35%) reported only indirect contact (e.g., walking through a swine barn). Two children required hospitalization; all patients recovered. This outbreak highlights the risk, particularly among children, for contracting variant influenza virus at agricultural fairs after direct or indirect swine contact. Publicizing CDC's recommendation that persons at high risk for serious influenza complications avoid pigs and swine barns might help prevent future variant influenza outbreaks among vulnerable groups (1)., Competing Interests: All authors have completed and submitted the ICMJE form for disclosure of potential conflicts of interest. Jennifer Chang disclosed receipt of personal fees as an employee and co-owner of Complex Computation, LLC. No other potential conflicts of interest were disclosed.

Objective: To assess knowledge, attitudes, and behaviors toward West Nile virus (WNV) prevention among Maryland adults ≥60 years old who are at increased risk of severe WNV disease utilizing the health belief model., Methods: Using a stratified random sample of households from zip codes with ≥2 human WNV cases, we conducted a telephone survey of 211 Maryland adults ≥60 years old between October and December 2012., Results: Participants expressing worry about WNV were over thrice more likely to use insect repellent in the prior 90 days (adjusted odds ratio [aOR] = 3.46, 95% confidence interval [CI] = 1.33-8.95) and nearly thrice more likely to drain standing water around their homes than those not worried (aOR = 2.86, 95% CI = 1.25-6.52). Respondents perceiving a benefit in paying less for WNV vaccine were more likely to support mosquito control programs (aOR = 16.00, 95% CI = 1.50-170.68)., Conclusions: Future interventions to promote WNV prevention among older adults should seek to enhance perceptions of vulnerability to WNV through risk communication, including media outreach and written messaging, emphasizing the benefits of personal protective behaviors. Community partnerships may aid in outreach to this population.

In June 2016, the Maryland Department of Health and Mental Hygiene (DHMH) was notified of a nonpregnant woman who sought treatment for a subjective fever and an itchy rash, which was described as maculopapular by her provider. Laboratory testing at the Maryland DHMH Laboratories Administration confirmed Zika virus infection. Case investigation revealed that the woman had not traveled to a region with ongoing transmission of Zika virus, but did have sexual contact with a male partner who had recently traveled to the Dominican Republic. The male partner reported exposure to mosquitoes while traveling, but no symptoms consistent with Zika virus infection either before or after returning to the United States. The woman reported no other sex partners during the 14 days before onset of her symptoms and no receipt of blood products or organ transplants.

During 2013, the Maryland Department of Health and Mental Hygiene in Baltimore, MD, USA, received report of 2 Maryland residents whose surgical sites were infected with rapidly growing mycobacteria after cosmetic procedures at a clinic (clinic A) in the Dominican Republic. A multistate investigation was initiated; a probable case was defined as a surgical site infection unresponsive to therapy in a patient who had undergone cosmetic surgery in the Dominican Republic. We identified 21 case-patients in 6 states who had surgery in 1 of 5 Dominican Republic clinics; 13 (62%) had surgery at clinic A. Isolates from 12 (92%) of those patients were culture-positive for Mycobacterium abscessus complex. Of 9 clinic A case-patients with available data, all required therapeutic surgical intervention, 8 (92%) were hospitalized, and 7 (78%) required ≥3 months of antibacterial drug therapy. Healthcare providers should consider infection with rapidly growing mycobacteria in patients who have surgical site infections unresponsive to standard treatment.

Background: In the northeastern United States, tick-borne diseases are a major public health concern. In controlled studies, a single springtime application of acaricide has been shown to kill 68%-100% of ticks. Although public health authorities recommend use of acaricides to control tick populations in yards, the effectiveness of these pesticides to prevent tick bites or human tick-borne diseases is unknown., Methods: We conducted a 2-year, randomized, double-blinded, placebo-controlled trial among 2727 households in 3 northeastern states. Households received a single springtime barrier application of bifenthrin or water according to recommended practices. Tick drags were conducted 3-4 weeks after treatment on 10% of properties. Information on human-tick encounters and tick-borne diseases was collected through monthly surveys; reports of illness were validated by medical record review., Results: Although the abundance of questing ticks was significantly lower (63%) on acaricide-treated properties, there was no difference between treatment groups in human-tick encounters, self-reported tick-borne diseases, or medical-record-validated tick-borne diseases., Conclusions: Used as recommended, acaricide barrier sprays do not significantly reduce the household risk of tick exposure or incidence of tick-borne disease. Measures for preventing tick-borne diseases should be evaluated against human outcomes to confirm effectiveness., (Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.)

Large commercial laboratories in the United States were surveyed regarding the number of specimens tested for eight tickborne diseases in 2008. Seven large commercial laboratories reported testing a total of 2,927,881 specimens nationally (including Lyme disease). Of these, 495,585 specimens (17%) were tested for tickborne diseases other than Lyme disease. In addition to large commercial laboratories, another 1051 smaller commercial, hospital, and government laboratories in four states (CT, MD, MN, and NY) were surveyed regarding tickborne disease testing frequency, practices, and results. Ninety-two of these reported testing a total of 10,091 specimens for four tickborne diseases other than Lyme disease. We estimate the cost of laboratory diagnostic testing for non-Lyme disease tickborne diseases in 2008 to be $9.6 million. These data provide a baseline to evaluate trends in tickborne disease test utilization and insight into the burden of these diseases., (Copyright © 2015 Elsevier GmbH. All rights reserved.)

Ticks are the most significant vectors of infectious diseases in the United States, inspiring many researchers to study aspects of their biology, ecology, and their effects on public health. However, regional differences in tick abundance and pathogen infection prevalence result in the inability to assume results from one area are relevant in another. Current local information on tick ranges, infection rates, and human cases is needed to assess tick-borne disease risk in any given region. The Mid-Atlantic Tick Summit III brought together over 100 area experts and researchers to share regional updates on ticks and their associated pathogens. We report some meeting highlights here. Regional meetings foster cross-disciplinary collaborations that benefit the community, and open novel lines of inquiry so that tick-bite risk can be reduced and tick-borne diseases can be treated effectively., (Copyright © 2015 Elsevier GmbH. All rights reserved.)

Background: Laboratory testing is helpful when evaluating patients with suspected Lyme disease (LD). A 2-tiered antibody testing approach is recommended, but single-tier and nonvalidated tests are also used. We conducted a survey of large commercial laboratories in the United States to assess laboratory practices. We used these data to estimate the cost of testing and number of infections among patients from whom specimens were submitted., Methods: Large commercial laboratories were asked to report the type and volume of testing conducted nationwide in 2008, as well as the percentage of positive tests for 4 LD-endemic states. The total direct cost of testing was calculated for each test type. These data and test-specific performance parameters available in published literature were used to estimate the number of infections among source patients., Results: Seven participating laboratories performed approximately 3.4 million LD tests on approximately 2.4 million specimens nationwide at an estimated cost of $492 million. Two-tiered testing accounted for at least 62% of assays performed; alternative testing accounted for <3% of assays. The estimated frequency of infection among patients from whom specimens were submitted ranged from 10% to 18.5%. Applied to the total numbers of specimens, this yielded an estimated 240 000 to 444 000 infected source patients in 2008., Discussion: LD testing is common and costly, with most testing in accordance with diagnostic recommendations. These results highlight the importance of considering clinical and exposure history when interpreting laboratory results for diagnostic and surveillance purposes., (Published by Oxford University Press on behalf of the Infectious Diseases Society of America 2014. This work is written by (a) US Government employee(s) and is in the public domain in the US.)

In August 2013, the Maryland Department of Health and Mental Hygiene (MDHMH) was notified of two persons with rapidly growing nontuberculous mycobacterial (RG-NTM) surgical-site infections. Both patients had undergone surgical procedures as medical tourists at the same private surgical clinic (clinic A) in the Dominican Republic the previous month. Within 7 days of returning to the United States, both sought care for symptoms that included surgical wound abscesses, clear fluid drainage, pain, and fever. Initial antibiotic therapy was ineffective. Material collected from both patients' wounds grew Mycobacterium abscessus exhibiting a high degree of antibiotic resistance characteristic of this organism.

Objective: Vibrio is a naturally occurring waterborne pathogen with potential occupational, recreational, and commercial impacts. During the last 15 years in the U.S. and in Maryland, the incidence of vibriosis has increased. Due to the increase in cases in Maryland, warming water temperatures, and public concern about human health effects resulting from exposure to the Chesapeake Bay, we reviewed cases of vibriosis and evaluated the Vibrio surveillance system in Maryland for timeliness and data quality, attributes necessary for successful outbreak investigation and illness prevention., Methods: The evaluation included (1) informal qualitative surveys of state and local personnel who report and manage Vibrio cases and (2) a review of Vibrio surveillance data from 2002 through 2008 for data quality and timeliness of the system., Results: From 2002 to 2008, 188 laboratory-confirmed cases of vibriosis were reported in Maryland with an annual average of 27 cases. The species of Vibrio that were most frequently responsible for infection, regardless of clinical presentation, were V. parahaemolyticus (43.6%), V. vulnificus (23.9%), V. alginolyticus (9.6%), and non-toxigenic V. cholerae (9.0%). The case fatality rate fluctuated during the study period, but the number of cases increased., Conclusions: The surveillance system in Maryland is flexible and captures cases of vibriosis where specimens were collected for testing; however, the system may not adequately capture mild, self-limiting infections. Better integration of data collection for clinical, laboratory, and environmental information and improved completion of variables for shellfish harvest or water exposure locations could improve the system. Quarterly meetings comprising surveillance, public health laboratory, and food-control personnel could direct and ensure the success of improvement efforts.

Importance: The rabies virus causes a fatal encephalitis and can be transmitted through tissue or organ transplantation. In February 2013, a kidney recipient with no reported exposures to potentially rabid animals died from rabies 18 months after transplantation., Objectives: To investigate whether organ transplantation was the source of rabies virus exposure in the kidney recipient, and to evaluate for and prevent rabies in other transplant recipients from the same donor., Design: Organ donor and all transplant recipient medical records were reviewed. Laboratory tests to detect rabies virus-specific binding antibodies, rabies virus neutralizing antibodies, and rabies virus antigens were conducted on available specimens, including serum, cerebrospinal fluid, and tissues from the donor and the recipients. Viral ribonucleic acid was extracted from tissues and amplified for nucleoprotein gene sequencing for phylogenetic comparisons., Main Outcomes and Measures: Determination of whether the donor died from undiagnosed rabies and whether other organ recipients developed rabies., Results: In retrospect, the donor's clinical presentation (which began with vomiting and upper extremity paresthesias and progressed to fever, seizures, dysphagia, autonomic dysfunction, and brain death) was consistent with rabies. Rabies virus antigen was detected in archived autopsy brain tissue collected from the donor. The rabies viruses infecting the donor and the deceased kidney recipient were consistent with the raccoon rabies virus variant and were more than 99.9% identical across the entire N gene (1349/1350 nucleotides), thus confirming organ transplantation as the route of transmission. The 3 other organ recipients remained asymptomatic, with rabies virus neutralizing antibodies detected in their serum after completion of postexposure prophylaxis (range, 0.3-40.8 IU/mL)., Conclusions and Relevance: Unlike the 2 previous clusters of rabies virus transmission through solid organ transplantation, there was a long incubation period in the recipient who developed rabies, and survival of 3 other recipients without pretransplant rabies vaccination. Rabies should be considered in patients with acute progressive encephalitis of unexplained etiology, especially for potential organ donors. A standard evaluation of potential donors who meet screening criteria for infectious encephalitis should be considered, and risks and benefits for recipients of organs from these donors should be evaluated.

The Virginia-Maryland Regional College of Veterinary Medicine (VMRCVM), a regional veterinary college for Maryland and Virginia, has a long and unique tradition of encouraging careers in public and corporate veterinary medicine. The VMRCVM is home to the Center for Public and Corporate Veterinary Medicine (CPCVM), and each year approximately 10% of the veterinary students choose the public/corporate veterinary medicine track. The faculty of the CPCVM, and their many partners from the veterinary public practice community, teach in the veterinary curriculum and provide opportunities for students locally, nationally, and internationally during summers and the final clinical year. Graduates of the program work for government organizations, including the US Department of Agriculture, the Food and Drug Administration, and the Centers for Disease Control and Prevention, as well as in research, in industry, and for non-governmental organizations. Recent activities include securing opportunities for students, providing career counseling for graduate veterinarians interested in making a career transition, delivering continuing education, and offering a preparatory course for veterinarians sitting the board examination for the American College of Veterinary Preventive Medicine. As the VMRCVM moves forward in recognition of the changing needs of the veterinary profession, it draws on its tradition of partnership and capitalizes on the excellence of its existing program. Future plans for the CPCVM include possible expansion in the fields of public health, public policy, international veterinary medicine, organizational leadership, and the One Health initiative. Quality assurance and evaluation of the program is ongoing, with recognition that novel evaluation approaches will be useful and informative.

We used population-based hospital discharge data to describe hospitalizations resulting from dog bites in California from 1991 through 1998, when there were 6676 such hospitalizations (average 835 per year; range 732 to 930), and the annual cumulative incidence for all ages was 2.6 per 100 000. Children had more than twice the risk of adults, and Asians had lower rates than Whites. Children aged 0 to 9 years were more likely to suffer wounds to the head and face.

We conducted a serosurvey of landscapers to determine if they were at increased risk for exposure to Francisella tularensis and to determine risk factors for infection. In Martha's Vineyard, Massachusetts, landscapers (n=132) were tested for anti-F. tularensis antibody and completed a questionnaire. For comparison, serum samples from three groups of nonlandscaper Martha's Vineyard residents (n=103, 99, and 108) were tested. Twelve landscapers (9.1%) were seropositive, compared with one person total from the comparison groups (prevalence ratio 9.0; 95% confidence interval 1.2 to 68.1; p=0.02). Of landscapers who used a power blower, 15% were seropositive, compared to 2% who did not use a power blower (prevalence ratio 9.2; 95% confidence interval 1.2 to 69.0; p=0.02). Seropositive landscapers worked more hours per week mowing and weed-whacking and mowed more lawns per week than their seronegative counterparts. Health-care workers in tularemia-endemic areas should consider tularemia as a diagnosis for landscapers with a febrile illness.

Objectives: To identify cases and determine risk factors for an outbreak of Escherichia coli (E. coli) O157: nonmotile (NM) infections in children attending a summer day care program in California., Methods: The authors conducted a retrospective cohort study; the cohort comprised first and second graders who attended the day care program during the last week in August 1999. Shiga toxin testing and molecular subtyping using pulsed-field gel electrophoresis were performed on isolates. Lake water, lake bottom sediment samples, and waterfowl feces from the lake environs were cultured for E. coli O157., Results: Three cases of Shiga toxin-producing E. coli O157: NM infections with matching pulsed-field gel electrophoresis patterns and four probable cases were found. Children who swallowed more than a mouthful of water had a higher attack rate than those who swallowed less than a mouthful or none at all (43% vs. 10%, relative risk = 4.43, 95% confidence interval 1.12, 17.50)., Conclusions: E. coli O157: NM infections were associated with swallowing water from a freshwater lake. Potential sources of contamination include feces from humans, cattle, or deer. This outbreak illustrates the value in screening patients with diarrhea for E. coli O157, submitting isolates to public health laboratories, and using molecular techniques to identify related cases. Outbreaks associated with contaminated freshwater could be averted by prevention and early detection of contamination.