Rocky Mountain spotted fever in the United States, 1993-1996

During 1993 through 1996, 2,313 cases of Rocky Mountain spotted fever (RMSF) were reported to the Centers for Disease Control and Prevention (CDC) by 42 states and the District of Columbia through the National Electronic Telecommunications System for Surveillance (NETSS). During this same interval, 1,752 case report forms (CRFs) were submitted to CDC and 1,253 (70%) of the cases were categorized as confirmed RMSF by laboratory testing. On the basis of analyses performed with NETSS data, the average annual RMSF incidence during 1993-1996 was 2.2 cases per million persons; the incidence rose from 1.8 in 1993 to 3.3 per million persons in 1996. Incidence for confirmed cases was highest among children 5-9 years of age (3.7 per million) and lowest among individuals older than 70 years of age (1.4 per million). The south Atlantic region accounted for the largest proportion of confirmed cases (52%). The case-fatality rate was highest among persons 70 years of age and older (9.0%) and lowest among adults 40-49 years of age (0.6%).     

Rocky Mountain Spotted Fever in the United States, 2000–2007: Interpreting Contemporary Increases in Incidence

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.     

Analysis of risk factors for fatal Rocky Mountain Spotted Fever: evidence for superiority of tetracyclines for therapy.

Epidemiologic and clinical characteristics of fatal and nonfatal cases of Rocky Mountain spotted fever (RMSF) were compared to identify risk factors for death caused by this disease. Confirmed and probable RMSF cases reported through US national surveillance for 1981-1998 were analyzed. Among 6388 RMSF patients, 213 died (annual case-fatality rate, 3.3%; range, 4.9% in 1982 to 1.1% in 1996). Use of tetracycline-class antibiotics for treatment of RMSF increased significantly in the 1990s, compared with use in the 1980s. Older patients, patients treated with chloramphenicol only, patients for whom tetracycline antibiotics were not the primary therapy, and patients for whom treatment was delayed > or =5 days after the onset of symptoms were at higher risk for death. Although the case-fatality rate was lower in the 1990s than in the 1980s, risk factors for fatal RMSF were similar. Despite the availability of effective antibiotics, RMSF-related deaths continue to occur because of delayed diagnosis and failure to use appropriate therapy.     

Rocky mountain spotted fever hospitalizations among American Indians

To describe the epidemiology of Rocky Mountain spotted fever (RMSF) among American Indians/Alaska Natives (AI/ANs), we conducted a retrospective analysis of hospitalization records with an RMSF diagnosis using Indian Health Service (IHS) hospital discharge data for calendar years 1980-2003. A total of 261 RMSF hospitalizations were reported among AIs, for an average annual hospitalization rate of 1.21 per 100,000 persons; two deaths were reported (0.8%). Most hospitalizations (88.5%) occurred in the Southern Plains region, where the rate was 4.23 per 100,000 persons. Children 1-4 years of age had the highest age-specific hospitalization rate of 2.50 per 100,000 persons. The overall annual RMSF hospitalization rate declined during the study period. Understanding the epidemiology of RMSF among AI/ANs and educating IHS/tribal physicians on the diagnosis of tick-borne diseases remain important for the prompt treatment of RMSF and the reduction of the disease occurrence among AI/ANs, particularly in high-risk areas.     

Surveillance of Rocky Mountain spotted fever in the United States, 1981-1983

Surveillance of Rocky Mountain spotted fever (RMSF) in the United States has revealed a stable incidence of the disease from 1981 to 1983, with a median of 0.48 cases/100,000 population per year (range, 0.42-0.52). During this three-year period an increase in both the number and the percentage of total cases reported from the West South Central states was observed when compared with previous three-year periods. An expanded case report form, which was introduced in 1981 for use by state health departments, was received for 2,850 (87%) of the 3,294 cases reported in 1981-1983. Of these 2850 cases, 1375 (48%) were laboratory confirmed. Death from RMSF was more common in persons greater than or equal to 30 years of age (case-fatality ratio of 8.4%) than in persons less than 30 years (2.2%, P less than .001). Fatality was also associated with failure to obtain a history of a tick bite within 14 days before onset of illness (P less than .05) and with lack of treatment with tetracycline or chloramphenicol (P less than .01).     

Increasing incidence of Ehrlichia chaffeensis and Anaplasma phagocytophilum in the United States, 2000-2007

Ehrlichia chaffeensis causes human monocytic ehrlichiosis, and Anaplasma phagocytophilum causes human granulocytic anaplasmosis. These related tick-borne rickettsial organisms can cause severe and fatal illness. During 2000-2007, the reported incidence rate of E. chaffeensis increased from 0.80 to 3.0 cases/million persons/year. The case-fatality rate was 1.9%, and the hospitalization rate was 49%. During 2000-2007, the reported incidence of A. phagocytophilum increased from 1.4 to 3.0 cases/million persons/year. The case-fatality rate was 0.6%, and the hospitalization rate was 36%. Rates among female patients were lower than among male patients for ehrlichiosis (rate ratio = 0.68) and anaplasmosis (rate ratio = 0.70). Most (80%) ehrlichiosis and anaplasmosis cases met only a probable case definition, although, use of a polymerase chain reaction to confirm infections increased during 2000-2007. Heightened reporting of these diseases will likely continue with improving recognition, changing surveillance practices, and appropriate application of diagnostic assays.     

Adenocarcinomas of the colon and rectum in persons under 40 years old. A population-based study

Data collected by nine population-based tumor registries participating in the Surveillance, Epidemiology, and End Results Program of the National Cancer Institute were analyzed to characterize the epidemiology of noncarcinoid adenocarcinomas of the colon and rectum in young adults. Tumors diagnosed in persons under 40 years old between 1973 and 1984 (n = 1736) were compared with those in persons 40 years and older (n = 106,760). This first large U.S. population-based study of colorectal adenocarcinomas in the young shows a higher incidence in blacks than whites and later detection in black males. It also shows a higher proportion of tumors of mucinous and signet ring histological type than in older age groups. Among the younger group, the average annual age-adjusted incidence rate was 34% higher in black males than in white males (12.6 vs. 9.4 per million persons) and 46% higher in black females than in white females (13.0 vs 8.9 per million persons). The proportion of tumors that were right-sided varied by age: 0-29 years, 30%; 30-39 years, 26%; 40-49 years, 22%; 50-59 years, 21%; 60-69 years, 24%; 70-79 years, 30%; and 80+ years, 35%. Males under age 40 were less likely to present with localized disease (whites, 27%; blacks, 21%) than were those aged 40 and older (whites, 39%; blacks, 36%). The proportion of tumors classified as mucinous decreased with age, from 28% among those aged 0-19 years to 5% among those 40 years and older. A similar trend was observed for signet ring tumors. Although this latter type accounted for 10% of large-bowel tumors among subjects aged 0-19 years, this proportion decreased with age to 0.2% in those 40 years and older.     

Incidence of aplastic anemia in Bangkok. The Aplastic Anemia Study Group

The annual incidence of aplastic anemia in metropolitan Bangkok, Thailand, and its five suburban provinces was prospectively determined. All patients first diagnosed during the period from January through December 1989 who met specific clinical and pathologic criteria were included. Thirty-two cases were identified, yielding an overall incidence of 3.7 per million. The incidence rates for the age groups 0 through 24, 25 through 59, and over 60 years were 4.3, 3.2, and 2.1 per million, respectively; the highest rate, 7.2 per million, was found for individuals aged 15 to 24 years. The male-to-female ratio was 1.9. The incidence of aplastic anemia in Bangkok is higher than that reported in recent European studies. The peak rate in young persons is almost fourfold higher than in comparable recent western studies and suggests an environmental etiology peculiar to Thailand.     

Epidemiology of systemic vasculitis: a ten-year study in the United Kingdom

OBJECTIVE: To describe the epidemiology of the primary systemic vasculitides (PSV; Wegener's granulomatosis, Churg-Strauss syndrome, microscopic polyangiitis, polyarteritis nodosa) in a well-defined population over a 10-year period. METHODS: An inception cohort of patients from the Norwich Health Authority (NHA) who were >15 years of age and had PSV first diagnosed between January 1, 1988 and December 31, 1997 was collected. Incidence rates were adjusted for age and sex to the 1992 population. The prevalence of PSV in this cohort was estimated on December 31, 1997. Patients were classified according to the American College of Rheumatology 1990 vasculitis criteria and the Chapel Hill Consensus definitions. RESULTS: Eighty-two NHA residents fulfilled the inclusion criteria. There were 47 men and 35 women, with a mean age of 62.9 years (median 65.0 years). The overall annual incidence of PSV among NHA residents was 19.8/million (95% confidence interval [95% CI] 15.8-24.6). The point prevalence on December 31, 1997 was 144.5/million (95% CI 110.4-185.3). PSV was more common in males (23.5/million; 95% CI 17.3-31.3) than females (16.4/million; 95% CI 11.4-22.8). The age- and sex-specific incidence showed a clear increase with age, with an overall peak in the 65-74 year age group (60.1/million). CONCLUSION: In our study population, the annual incidence of PSV is slowly increasing with time and the incidence is greatest in the elderly.     

Epidemiology and natural history of Wilson's disease in the Chinese: A territory-based study in Hong Kong between 2000 and 2016

AIM To investigate the epidemiology and natural history of Wilson's disease in the Chinese.METHODS Data were retrieved via electronic search of hospital medical registry of the Hong Kong Hospital Authority,which covers all the public healthcare services. We identified cases of Wilson's disease between 2000 and 2016 by the International Classification of Diseases(ICD)-9 code. We analyzed the incidence rate,prevalence and adverse outcomes of Wilson's disease.RESULTS We identified 211 patients(male cases 104; female cases 107; median age 27.2 years,IQR: 17.1-38.6 years; duration of follow-up 8.0 years,IQR: 5.0-14.0 years). The average annual incidence rate was 1.44 per million person-years while the prevalence was 17.93 per million. Between 2000 and 2016,there was a decrease in the annual incidence rate from 1.65 to 1.23 per million person-years(P = 0.010),whereas there was an increase in the annual prevalence from 7.80 to 25.20 per million(P 0.001). Among the 176 cases with hepatic involvement,38(21.6%) had cirrhosis,three(1.7%) developed hepatocellular carcinoma,24(13.6%) underwent liver transplantations,and 26(14.8%) died. Seven patients had concomitant chronic viral hepatitis B or C. The 5-year and 10-years rates of overall survival were 92.6% and 89.5%,and for transplant-free survival rates 91.8% and 87.4%,respectively. Cirrhosis and possibly chronic viral hepatitis were associated with poorer overall survival. CONCLUSION There was a significant increase in the prevalence of Wilson's disease in Hong Kong. The prognosis was favorable except for those with cirrhosis or concomitant viral hepatitis.     

National surveillance and the epidemiology of human Q fever in the United States, 1978-2004

Although Q fever is considered enzootic in the United States, surveillance for human Q fever has been historically limited. From 1978 through 1999, 436 cases (average = 20 per year) of human Q fever were reported. After Q fever became nationally reportable in 1999, 255 human Q fever cases (average = 51 per year) were reported with illness onset during 2000 through 2004. The median age of cases was 51 years, and most cases were male (77%). The average annual incidence of Q fever was 0.28 cases per million persons, and was highest in persons 50-59 years of age (0.39 cases per million). State-specific incidence ranged from a high of 2.40 cases per million persons in Wyoming, to 0 cases in some states. Since Q fever became reportable, case reports have increased by more than 250%. Surveillance for Q fever is essential to establish the distribution and magnitude of disease and to complement U.S. bioterrorism preparedness activities.     

Disminución de la tuberculosis osteoarticular en España entre 1997 y 2018

Background and objectiveOsteoarticular tuberculosis represents 2-5% of the manifestations of tuberculosis. The objective was to calculate the incidence and describe the epidemiological characteristics of patients with osteoarticular tuberculosis who received hospital care in Spain between 1997-2018.MethodsA retrospective study was conducted of patients treated with osteoarticular tuberculosis in Spanish hospitals between 1997 and 2018, using the data from the Minimum Basic Data Set at hospital discharge, using the ICD-9-CM and ICD-10 codes.Results5710 patients with osteoarticular tuberculosis were detected over the 22 years in Spain. The mean annual incidence for the period was 6 cases per million inhabitants (95% CI 5.58-6.30). There was a significant difference between the mean annual incidence per million inhabitants of the first period (1997-2007) of 6.95 and that of the second (2008-2018) of 5.35 (p < .001).ConclusionsThe incidence of osteoarticular tuberculosis in Spain is low, has reduced over 22 years and predominates in men.     

Trends in clinical diagnoses of Rocky Mountain spotted fever among American Indians, 2001-2008

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.     

Fatal Rocky Mountain spotted fever in the United States, 1999-2007

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.     

Measles outbreak in Sri Lanka, 1999-2000

A large measles outbreak occurred in Sri Lanka from October 1999 through June 2000 following a period of low incidence. During this period, >15,000 suspected cases were reported to the central Epidemiological Unit of the Department of Health Services. The outbreak was investigated through review of surveillance data for 1999-2000, which were compared with previous surveillance data. Among the clinically confirmed cases, the highest morbidity rate (114/100,000 population) was observed among children <9 months of age. Nearly 54% of the cases were among persons >/=15 years old, and this percentage had increased over the previous decade. Forty percent of cases had a history of measles vaccination. There were 5 deaths, giving a case-fatality rate of 0.1%. Action taken during the outbreak and plans for future outbreak prevention strategies were also evaluated.     

Crohn's disease in the over-60 age group: a population based study

OBJECTIVES: Late-onset Crohn's disease (CD) may show a distinctive pattern of expression. The aim of our study was to describe the incidence or presentation of CD in the elderly and compare the outcomes in patients < 60 years or > or = 60 years at diagnosis. METHODS: The study included a population based inception cohort of all incident CD cases diagnosed in Brittany (France) between 1994 and 1997. Sixty-three patients were > or = 60 years and 201 were < 60 years at diagnosis. The physicians managing the patients used standardized questionnaires to collect the study data. The questionnaires on outcomes and treatments were completed in 2002. RESULTS: In patients > or = 60 years, the annual incidence was 2.5 per 10 persons and clinical features were similar to those in younger patients, except for a higher rate of colon involvement. Among older patients, those with diverticula (29/63, 46%) were more likely to have granulomas (58% vs 33% of patients without diverticula, P < 0.04), but the diagnosis of CD was confirmed by lesions remote from the diverticula in most cases (23/29). Early resection rates were not higher in older patients, who were less likely to require immunosuppressants or re-admission for CD flares, as compared to younger patients. Five year mortality in older patients was 16% but was unrelated to CD. CONCLUSIONS: In Brittany, the age specific incidence, clinical features, and prognosis of CD among the elderly are comparable to those in younger individuals. Colon involvement is more common. Concomitant diverticular disease is common and should prompt a search for CD lesions at other sites to confirm the diagnosis. Older patients are less likely to require immunosuppressants or admission for flares.     

Epidemiologic features of infective endocarditis in Taiwanese adults involving native valves

Little is known about the incidence and clinical outcomes of infective endocarditis (IE) involving native valves in Asian countries. This nationwide study investigated epidemiologic features and in-hospital mortality associated with IE in adults (age > or =18 years) based on Taiwan's National Health Insurance database from 1997 through 2002. Of 7,240 enrolled patients with IE involving native valves, the mean age was 53 +/- 19 years and 70% were men. The mean annual crude incidence was 7.6 per 100,000 inhabitants. The incidence was significantly higher in men than in women (10.4 vs 4.6 per 100,000; p <0.001). The incidence of IE increased steadily with age, ranging from 3.8 per 100,000 persons in patients <30 years of age to 33 per 100,000 persons in patients > or =80 years of age (p <0.001). Staphylococcal (32%) and streptococcal species (61%) were the most common causative pathogens. The mean in-hospital mortality rate was 18%. Multivariate analysis showed that male gender, older age (> or =50 years), diabetes mellitus, heart failure, neurologic complications, renal insufficiency, respiratory failure, shock, and Staphylococcus species as the causative microorganism were independent predictors of in-hospital mortality. In conclusion, this Taiwanese study revealed a high incidence of IE in men and elderly subjects. The in-hospital mortality rate remained high. Patients with IE who also developed shock and respiratory failure were the most likely to have a poor outcome.     

Hepatitis A outbreaks: the effect of a mass vaccination programme

A Hepatitis A vaccination programme of people belonging to risk groups begun in Catalonia in 1995 and a universal vaccination programme of pre-adolescents 12 years of age with the hepatitis A + B vaccine was added in 1998. The aim of the study was to investigate the characteristics of hepatitis A outbreaks occurring in Catalonia between 1991 and 2007 to determine the associated risk factors and optimize the use of vaccination. Incidence rates of outbreaks, cases and hospitalizations associated with outbreaks and the rate ratios (RR) of person-to-person transmission outbreaks between the periods before and after mass vaccination and their 95% confidence intervals (CI) were calculated. A rate of 2.45 outbreaks per million persons per year was found. The rate of cases affected in these outbreaks was 1.28 per 10(5) persons per year and the rate of hospitalizations was 0.45 per million persons per year. In person-to-person outbreaks, the highest incidence rate (5.26 and 6.33 per million persons per year) of outbreaks according to the age of the index case was in the 5 to 14 year age group in both periods (RR:0.83; 95% CI:0.48-1.43). A significant increase was observed in the 25 to 44 year age group (RR: 0.35; 95% CI 0.14-0.77). Hepatitis A vaccination has made an important impact on burden and characteristics of outbreaks and could provide greater benefits to the community if the vaccine was administrated to children during their first years of life.     

Epidemiology of pneumonia hospitalizations in Spain, 1995-1998

OBJECTIVES: This epidemiological survey was undertaken to estimate the burden of hospital admissions for pneumonia in Spain during a four-year period (1995-1998). METHODS: Data were obtained from the national surveillance system for hospital data. RESULTS: There were 231,512 hospital admissions for pneumonia (ICD 9 CM 480-486; first listed diagnosis) during this period, that is an annual incidence of 177 cases per 100,000 population. The incidence was higher in children <5 years of age and in persons >or=65 years compared with other age groups. The annual cost of these hospitalizations to the National Health Care System was of 127 million ECUS. CONCLUSIONS: Preventive measures, such as vaccination of population groups at high risk, to reduce pneumonia-related morbidity could result in large cost savings to the National Health Care System.