Ehrlichiosis and anaplasmosis infections among American Indians (AIs) have never been specifically examined, despite high rates of other tick-borne rickettsial diseases among AIs. The epidemiology of ehrlichiosis and anaplasmosis among AIs was analyzed using the National Electronic Telecommunications System for Surveillance (NETSS), Case Report Forms (CRFs), and Indian Health Service (IHS) inpatient and outpatient visits. The 2000–2007 average annual ehrlichiosis and anaplasmosis incidence among AIs reported to NETSS was almost 4-fold lower (4.0/1,000,000) than that using IHS data (14.9). American Indian cases reported from CRFs had a higher proportion of hospitalization (44%) compared with IHS (10%). American Indian incidence of ehrlichiosis and anaplasmosis was higher and showed a different age and geographical distribution than other races. These results highlight the need to improve collaboration between the ehrlichiosis and anaplasmosis surveillance systems for AIs so as to develop interventions that target the unique epidemiology and mitigate the burden of disease among this high-risk population.
Death from Rocky Mountain spotted fever (RMSF) is preventable with prompt,
appropriate treatment. Data from two independent sources were analyzed to
estimate the burden of fatal RMSF and identify risk factors for fatal RMSF in
the United States during 1999–2007. Despite increased reporting of RMSF
cases to the Centers for Disease Control and Prevention, no significant changes
in the estimated number of annual fatal RMSF cases were found. American Indians
were at higher risk of fatal RMSF relative to whites (relative risk [RR]
= 3.9), and children 5–9 years of age (RR = 6.0) and adults
≥ 70 years of age (RR = 3.0) were also at increased risk relative
to other ages. Persons with cases of RMSF with an immunosuppressive condition
were at increased risk of death (RR = 4.4). Delaying treatment of RMSF
was also associated with increased deaths. These results may indicate a gap
between recommendations and practice.
lymphocytic choriomeningitis virus; LCMV; viruses; lymphocytic choriomeningitis; American Indians; incidence; electronic diagnostic codes; chart review; International Classification of Diseases; ICD-9
American Indians are at greater risk for Rocky Mountain spotted fever (RMSF) than the general U.S. population. The epidemiology of RMSF among American Indians was examined by using Indian Health Service inpatient and outpatient records with an RMSF International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis. For 2001–2008, 958 American Indian patients with clinical diagnoses of RMSF were reported. The average annual RMSF incidence was 94.6 per 1,000,000 persons, with a significant increasing incidence trend from 24.2 in 2001 to 139.4 in 2008 (P = 0.006). Most (89%) RMSF hospital visits occurred in the Southern Plains and Southwest regions, where the average annual incidence rates were 277.2 and 49.4, respectively. Only the Southwest region had a significant increasing incidence trend (P = 0.005), likely linked to the emergence of brown dog ticks as an RMSF vector in eastern Arizona. It is important to continue monitoring RMSF infection to inform public health interventions that target RMSF reduction in high-risk populations.
To examine the epidemiology of infectious disease (ID) hospitalisations among Alaska Native (AN) people.
Hospitalisations with a first-listed ID diagnosis for American Indians and ANs residing in Alaska during 2001–2009 were selected from the Indian Health Service direct and contract health service inpatient data. ID hospitalisations to describe the general US population were selected from the Nationwide Inpatient Sample. Annual and average annual (2007–2009) hospitalization rates were calculated.
During 2007–2009, IDs accounted for 20% of hospitalisations among AN people. The 2007–2009 average annual age-adjusted ID hospitalisation rate (2126/100,000 persons) was higher than that for the general US population (1679/100,000; 95% CI 1639–1720). The ID hospitalisation rate for AN people increased from 2001 to 2009 (17%, p<0.001). Although the rate during 2001–2009 declined for AN infants (<1 year of age; p=0.03), they had the highest 2007–2009 average annual rate (15106/100,000), which was 3 times the rate for general US infants (5215/100,000; 95% CI 4783–5647). The annual rates for the age groups 1–4, 5–19, 40–49, 50–59 and 70–79 years increased (p<0.05). The highest 2007–2009 age-adjusted average annual ID hospitalisation rates were in the Yukon-Kuskokwim (YK) (3492/100,000) and Kotzebue (3433/100,000) regions; infant rates were 30422/100,000 and 26698/100,000 in these regions, respectively. During 2007–2009, lower respiratory tract infections accounted for 39% of all ID hospitalisations and approximately 50% of ID hospitalisations in YK, Kotzebue and Norton Sound, and 74% of infant ID hospitalisations.
The ID hospitalisation rate increased for AN people overall. The rate for AN people remained higher than that for the general US population, particularly in infants and in the YK and Kotzebue regions. Prevention measures to reduce ID morbidity among AN people should be increased in high-risk regions and for diseases with high hospitalisation rates.
Alaska Native; infectious disease; hospitalisations; Alaska; lower respiratory tract infection
We described the changing epidemiology of viral hepatitis among the American Indian/Alaska Native (AI/AN) population that uses Indian Health Service (IHS) health care.
We used hospital discharge data from the IHS National Patient Information Reporting System to determine rates of hepatitis A-, B-, and C-associated hospitalization among AI/ANs using IHS health care from 1995–2007 and summary periods 1995–1997 and 2005–2007.
Hepatitis A-associated hospitalization rates among AI/AN people decreased from 4.9 per 100,000 population during 1995–1997 to 0.8 per 100,000 population during 2005–2007 (risk ratio [RR] = 0.2, 95% confidence interval [CI] 0.1, 0.2). While there was no significant change in the overall hepatitis B-associated hospitalization rate between time periods, the average annual rate in people aged 45–64 years increased by 109% (RR=2.1, 95% CI 1.4, 3.2). Between the two time periods, the hepatitis C-associated hospitalization rate rose from 13.0 to 55.0 per 100,000 population (RR=4.2, 95% CI 3.8, 4.7), an increase of 323%. The hepatitis C-associated hospitalization rate was highest among people aged 45–64 years, males, and those in the Alaska region.
Hepatitis A has decreased to near-eradication levels among the AI/AN population using IHS health care. Hepatitis C-associated hospitalizations increased significantly; however, there was no significant change in hepatitis B-associated hospitalizations. Emphasis should be placed on continued universal childhood and adolescent hepatitis B vaccination and improved vaccination of high-risk adults. Prevention and education efforts should focus on decreasing hepatitis C risk behaviors and identifying people with hepatitis C infection so they may be referred for treatment.
We described disparities in infectious disease (ID) hospitalizations for American Indian/Alaska Native (AI/AN) people.
We analyzed hospitalizations with an ID listed as the first discharge diagnosis in 1998–2006 for AI/AN people from the Indian Health Service National Patient Information Reporting System and compared them with records for the general U.S. population from the Nationwide Inpatient Survey.
The ID hospitalization rate for AI/AN people declined during the study period. The 2004–2006 mean annual age-adjusted ID hospitalization rate for AI/AN people (1,708 per 100,000 populiation) was slightly higher than that for the U.S. population (1,610 per 100,000 population). The rate for AI/AN people was highest in the Southwest (2,314 per 100,000 population), Alaska (2,063 per 100,000 population), and Northern Plains West (1,957 per 100,000 population) regions, and among infants (9,315 per 100,000 population). ID hospitalizations accounted for approximately 22% of all AI/AN hospitalizations. Lower-respiratory--tract infections accounted for the largest proportion of ID hospitalizations among AI/AN people (35%) followed by skin and soft tissue infections (19%), and infections of the kidney, urinary tract, and bladder (11%).
Although the ID hospitalization rate for AI/AN people has declined, it remains higher than that for the U.S. general population, and is highest in the Southwest, Northern Plains West, and Alaska regions. Lower-respiratory-tract infections; skin and soft tissue infections; and kidney, urinary tract, and bladder infections contributed most to these health disparities. Future prevention strategies should focus on high-risk regions and age groups, along with illnesses contributing to health disparities.
Possible smallpox reemergence drives research for third-generation vaccines that effectively neutralize variola virus. A comparison of neutralization assays using different substrates, variola and vaccinia (Dryvax and modified vaccinia Ankara [MVA]), showed significantly different 90% neutralization titers; Dryvax underestimated while MVA overestimated variola neutralization. Third-generation vaccines may rely upon neutralization as a correlate of protection.
Educational outreach should inform the public about dangers of translocation of wild animals and general aspects of rabies.
Flagstaff, Arizona, USA, experienced notable outbreaks of rabies caused by a bat rabies virus variant in carnivore species in 2001, 2004, 2005, 2008, and 2009. The most recent epizootic involved transmission among skunk and fox populations and human exposures. Multiple, wide-ranging control efforts and health communications outreach were instituted in 2009, including a household survey given to community members. Although the Flagstaff community is knowledgeable about rabies and the ongoing outbreaks in general, gaps in knowledge about routes of exposure and potential hosts remain. Future educational efforts should include messages on the dangers of animal translocation and a focus on veterinarians and physicians as valuable sources for outreach. These results will be useful to communities experiencing rabies outbreaks as well as those at current risk.
rabies virus; lyssavirus; rabies; health knowledge; attitudes; practice; outbreak; epizootic; community survey; viruses; zoonosis; Arizona; United States; USA; translocation; wild animals; wildlife; education
Autopsy findings, clinical history, and diagnostic tools can aid surveillance and investigation of infectious diseases.
coroners and medical examiners; autopsy; communicable diseases; epidemiology; United States; bacteria; viruses
Rocky Mountain spotted fever (RMSF), a potentially fatal tick-borne infection caused by Rickettsia rickettsii, is considered a notifiable condition in the United States. During 2000 to 2007, the annual reported incidence of RMSF increased from 1.7 to 7 cases per million persons from 2000 to 2007, the highest rate ever recorded. American Indians had a significantly higher incidence than other race groups. Children 5–9 years of age appeared at highest risk for fatal outcome. Enzyme-linked immunosorbent assays became more widely available beginning in 2004 and were used to diagnose 38% of cases during 2005–2007. The proportion of cases classified as confirmed RMSF decreased from 15% in 2000 to 4% in 2007. Concomitantly, case fatality decreased from 2.2% to 0.3%. The decreasing proportion of confirmed cases and cases with fatal outcome suggests that changes in diagnostic and surveillance practices may be influencing the observed increase in reported incidence rates.
TOC summary: Decreased hospitalization rates suggest decline in complications from Helicobacter pylori infection.
Infection with Helicobacter pylori increases the risk for peptic ulcer disease (PUD) and its complications. To determine whether hospitalization rates for PUD have declined since antimicrobial drugs to eradicate H. pylori became available, we examined 1998–2005 hospitalization records (using the Nationwide Inpatient Sample) in which the primary discharge diagnosis was PUD. Hospitalizations for which the diagnosis was H. pylori infection were also considered. The age-adjusted hospitalization rate for PUD decreased 21% from 71.1/100,000 population (95% confidence interval [CI] 68.9–73.4) in 1998 to 56.5/100,000 in 2005 (95% CI 54.6–58.3). The hospitalization rate for PUD was highest for adults >65 years of age and was higher for men than for women. The age-adjusted rate was lowest for whites and declined for all racial/ethnic groups, except Hispanics. The age-adjusted H. pylori hospitalization rate also decreased. The decrease in PUD hospitalization rates suggests that the incidence of complications caused by H. pylori infection has declined.
peptic ulcer; duodenal ulcer; gastric ulcer; gastrojejunal ulcer; Helicobacter pylori; hospitalizations; enteric infections; bacteria; research
The search for a ‘third’-generation smallpox vaccine has resulted in the development and characterization of several vaccine candidates. A significant barrier to acceptance is the absence of challenge models showing induction of correlates of protective immunity against variola virus. In this light, virus neutralization provides one of few experimental methods to show specific ‘in vitro’ activity of vaccines against variola virus. Here, we provide characterization of the ability of a modified vaccinia virus Ankara vaccine to induce variola virus-neutralizing antibodies, and we provide comparison with the neutralization elicited by standard Dryvax vaccination.
To describe the occurrence of Kawasaki syndrome (KS) among different racial/ethnic groups in Hawai‘i.
Retrospective analysis of children <18 years of age, with a focus on children <5 years of age, living in Hawai‘i who were hospitalized with KS using the 1996–2006 Hawai‘i State Inpatient Data.
Children <5 years of age accounted for 84% of the 528 patients <18 years of age with KS. The average annual incidence among this age group was 50.4 per 100,000 children <5 years of age, ranging from 45.5 to 56.5. Asian and Pacific Islander children accounted for 92% of the children <5 years of age with KS during the study period; the average annual incidence was 62.9 per 100,000. Within this group, Japanese children had the highest incidence (210.5), followed by Native Hawaiian children (86.9), other Asian children (84.9), and Chinese children (83.2). The incidence for white children (13.7) was lower than for these racial/ethnic groups. The median age of KS admission for children <5 years of age was 21 months overall, 24 months for Japanese children, 14.5 months for Native Hawaiian children and 26.5 months for white children.
The high average annual KS incidence for children <5 years of age in Hawai‘i compared to the rest of the United States population reflects an increased KS incidence among Asian and Pacific Islander children, especially Japanese children. The incidence for white children was slightly higher than or similar to that generally reported nationwide.
Prion diseases are a family of rare, progressive, neurodegenerative disorders that affect humans and animals. The most common form of human prion disease, Creutzfeldt-Jakob disease (CJD), occurs worldwide. Variant CJD (vCJD), a recently emerged human prion disease, is a zoonotic foodborne disorder that occurs almost exclusively in countries with outbreaks of bovine spongiform encephalopathy.
This study describes the occurrence and epidemiology of CJD and vCJD in the United States.
Analysis of CJD and vCJD deaths using death certificates of US residents for 1979–2006, and those identified through other surveillance mechanisms during 1996–2008. Since CJD is invariably fatal and illness duration is usually less than one year, the CJD incidence is estimated as the death rate. During 1979 through 2006, an estimated 6,917 deaths with CJD as a cause of death were reported in the United States, an annual average of approximately 247 deaths (range 172–304 deaths). The average annual age-adjusted incidence for CJD was 0.97 per 1,000,000 persons. Most (61.8%) of the CJD deaths occurred among persons ≥65 years of age for an average annual incidence of 4.8 per 1,000,000 persons in this population. Most deaths were among whites (94.6%); the age-adjusted incidence for whites was 2.7 times higher than that for blacks (1.04 and 0.40, respectively). Three patients who died since 2004 were reported with vCJD; epidemiologic evidence indicated that their infection was acquired outside of the United States.
Surveillance continues to show an annual CJD incidence rate of about 1 case per 1,000,000 persons and marked differences in CJD rates by age and race in the United States. Ongoing surveillance remains important for monitoring the stability of the CJD incidence rates, and detecting occurrences of vCJD and possibly other novel prion diseases in the United States.
Kawasaki Syndrome (KS) is an uncommon childhood disease with unknown etiology. It has been suggested that rotavirus infection may play a causative role in the development of KS.
To examine potential temporal associations between KS and rotavirus infection, seasonal patterns of KS- and rotavirus-associated hospitalizations among children in California and New York during 2000-2005 were compared.
Rotavirus hospital admissions were markedly winter seasonal, with very few summer hospitalizations. KS hospitalizations occurred year-round but also peaked slightly during winter and spring.
The strong winter seasonal pattern of rotavirus clearly differed from the year-round pattern of KS hospitalizations. While the present study cannot completely rule out rotavirus as having a role in the development of KS, other agents must be involved in the etiology of KS.
The epidemiology of Molluscum contagiosum (MC) in the United States is largely unknown, despite the fact that the virus is directly communicable and large outbreaks occur. This study provides population-based estimates to describe the epidemiology of MC in the United States among American Indian and Alaska Native (AI/AN) persons. This population was selected because of the comprehensiveness and quality of available data describing utilization of out-patient services.
Outpatient visits listing MC as a diagnosis in the Indian Health Service National Patient Information Reporting System during 2001–2005 were analyzed to assess patient characteristics, visit frequency and concurrent skin conditions. Outpatient visit rates and incidence rates were calculated based on known population denominators (retrospective cohort). Overall outpatient visit rates were also calculated for the general US population using national data. The average annual rate of MC-associated outpatient visits was 20.15/10,000 AI/AN persons for 2001–2005 (13,711 total visits), which was similar to the rate for the general US population (22.0/10,000 [95% CI: 16.9–27.1]). The incidence of MC-associated visits was 15.34/10,000. AI/AN children 1–4 years old had the highest incidence (77.12), more than twice that for children 5–14 years old (30.79); the incidence for infants (<1 year) was higher than that for adults. AI/AN persons living in the West region had the highest incidence, followed by those in the East and Alaska regions (26.96, 22.88 and 21.38, respectively). There were age-specific associations between MC and concurrent skin conditions (e.g., atopic dermatitis, eczema).
This study highlights the need for periodic population-based measurements to assess trends in incidence and healthcare utilization for MC in the United States. High rates of MC were found among AI/AN persons, especially among children <15 years old. The AI/AN population would benefit from greater availability of effective strategies for prevention and treatment of MCV infection.
American Indians and Alaska Natives (AI/AN) adults ≥65 years of age (older adults) have the second highest age group-specific infectious disease (ID) hospitalization rate. To assess morbidity and disparities of IDs for older AI/AN adults, this study examined the epidemiology of overall and specific infectious disease hospitalizations among older AI/AN adults.
ID hospitalization data for older AI/AN adults were analyzed by using Indian Health Service hospital discharge data for 1990 through 2002 and comparing it with published findings for the general U.S. population of older adults.
ID hospitalizations accounted for 23% of all hospitalizations among older AI/AN adults. The average annual ID hospitalization rate increased 5% for 1990–1992 to 2000–2002; however, the rate increased more than 20% in the Alaska and the Southwest regions. The rate for older AI/AN adults living in the Southwest region was greater than that for the older U.S. adult population. For 2000–2002, lower respiratory tract infections accounted for almost half of all ID hospitalizations followed by kidney, urinary tract, and bladder infections, and cellulitis.
The ID hospitalization rate increased among older AI/AN adults living in the Southwest and Alaska regions, and the rate for the older AI/AN adults living in the Southwest region was higher than that for the U.S. general population. Prevention measures should focus on ways to reduce ID hospitalizations among older AI/AN adults, particularly those living in the Southwest and Alaska regions.
Infection is associated with proximity to virus-infected animals and their excretions and secretions.
For the 2003 monkeypox virus (MPXV) outbreak in the United States, interhuman transmission was not documented and all case-patients were near or handled MPXV-infected prairie dogs. We initiated a case–control study to evaluate risk factors for animal-to-human MPXV transmission. Participants completed a questionnaire requesting exposure, clinical, and demographic information. Serum samples were obtained for analysis of immunoglobulin G (IgG) and IgM to orthopoxvirus. When data were adjusted for smallpox vaccination, case-patients were more likely than controls to have had daily exposure to a sick animal (odds ratio [OR] 4.0, 95% confidence interval [CI] 1.2–13.4), cleaned cages and bedding of a sick animal (OR 5.3, 95% CI 1.4–20.7), or touched a sick animal (OR 4.0, 95% CI 1.2–13.4). These findings demonstrate that human MPXV infection is associated with handling of MPXV-infected animals and suggest that exposure to excretions and secretions of infected animals can result in infection.
Monkeypox; epidemiology; risk factor; smallpox vaccination; zoonotic; subclinical infection; research
OBJECTIVES: To describe the epidemiologic characteristics of patients hospitalized with Kawasaki syndrome (KS) and estimate associated costs in the United States, using a large national hospital discharge dataset. METHODS: Hospitalization discharge records with KS for 1997 through 1999 for U.S. residents <18 years of age were selected from Solucient's hospital discharge records. These records are collected from most of the self-governing children's hospitals and approximately one-third of short-term, non-federal general hospitals in the United States. RESULTS: A total of 7,431 hospital discharges with a KS diagnosis were identified; 2,270 of the discharges were in 1997, 2,700 in 1998, and 2,461 in 1999. Boys comprised 60.0% of the discharges, and 76.4% of discharges were among children ages <5 years. For the 44 states and the District of Columbia with at least one hospital reporting KS, the average annual KS hospitalization rate was 10.2 per 100,000 children ages <5 years. The KS hospitalization rate for boys (12.0 per 100,000) was higher than that for girls (8.3 per 100,000) (risk ratio 1.45; 95% confidence interval 1.37, 1.52). Extrapolation to the U.S. population showed an estimated average annual KS hospitalization rate of 21.6. The median KS hospitalization cost for children <5 years of age during the study period was $6,169 US dollars. CONCLUSIONS: The KS hospitalization rate was consistent with that of previous U.S. studies, although the extrapolated rate may be an overestimation. The median hospitalization cost for KS was higher than that for respiratory syncytial virus-associated bronchiolitis and diarrheal diseases. Large hospitalization datasets can be used to monitor the occurrence of KS in the United States.
We surveyed cavers who attended the National Speleological Society convention in June 2000. Fifteen percent of respondents did not consider a bat bite a risk for acquiring rabies; only 20% had received preexposure prophylaxis against the disease. An under-appreciation of the risk for rabies from bat bites may explain the preponderance of human rabies viruses caused by variant strains associated with bats in the United States.
rabies; lyssa virus; cavers; spelunkers; vaccination; bats; zoonoses