Human Mycobacterium bovis infection in the south-west of Ireland 1983-1992: a comparison with M. tuberculosis

Epidemiological and bacteriological aspects of human Mycobacterium bovis disease were investigated in south-west Ireland (counties Cork & Kerry, population 536,000) over the years 1983-92 inclusive and compared to M. tuberculosis. Results showed a small, stable incidence of culture positive M. bovis human disease, mean annual incidence 0.56 per 100,000 population compared to a higher but declining incidence of culture positive M. tuberculosis (15.3 per 100,000 in 1983, 9.0 per 100,000 in 1992). Male patients were the majority, 63.4 per cent of M. bovis; 62.4% of M. tuberculosis (p = 0.03). Fifty three per cent of M. bovis cases (n = 30) were pulmonary, compared to 85% of M. tuberculosis (n = 626; p = 0.0001). M. bovis patients were older (p = 0.02), mean age 58.4 years (SD 18.9) compared to 48.5 (SD 22.2). The mycobacterial smear positive rate was similar in both groups taken as a whole. No rural-urban difference in incidence was found in either disease, suggesting in the case of M. bovis initial infection in childhood via contaminated milk in the pre-pasteurisation era.     

Endogenous adenosine attenuates long-term depression and depotentiation in the CA1 region of the rat hippocampus

We describe a series of 144 cases of leptospirosis diagnosed in 1989 in New Caledonia. The incidence rate was 90 per 100,000 person-years, with a specific mortality rate of 4% patients. Those affected (100 males, 44 females) were mainly aged 20 to 40 years. Incidence in rural areas (112 per 100,000 person-years) was seven times higher than in urban settlements. Two periods with higher incidence were noticed corresponding to highest rainfall. Twenty-nine of the cases occurred in individuals with professions commonly associated with leptospirosis. Contacts with rats, dogs and ditch or river water were the most frequently mentioned. The clinical expression of the disease was polymorphic: 60% of the patients had mild symptoms, 40% were acute forms including Weil's disease. Of 57 hospitalized, 23% were admitted with an initial diagnosis of dengue, and 37% with leptospirosis. Main clinical syndromes were: icterus and/or renal syndrome in 50% of patients, cardiac syndrome in 65%, acute myalgies in 58% and pulmonary syndrome in 50%. Although hemorrhages were uncommon (17%), 40% of the cases demonstrated thrombocytopenia (< 50,000/m3). Pancreatic involvement with hyperamylasemia was evidenced in 50% of cases. Twelve serogroups of Leptospira were implicated, Icterohaemorragiae predominated (41%), but was not associated with severe forms. In New Caledonia, like in all tropics, leptospirosis must be considered as an environmental diseases, professional activities being just an additional risk factor. Use of serology as a reliable tool for confirmation of cases in areas of high environmental contamination is discussed.     

The current neurologic burden of illness and injury in the United States

Estimates of the need for neurologists must be based ultimately on the frequency of neurologic disease. Community-based population surveys for diseases or injuries that have come to medical attention provide annual incidence rates per 100,000 population, point prevalence rates per 100,000, and average duration in years. For 61 disorders, including for 8 only those fractions that were thought to require neurologic attention, the annual incidence rates summed to 2500 per 100,000 or 2.5% of the population. For 55 of these conditions, including for 6 only the neurologic fraction and excluding all mental retardation, blindness, deafness, or psychosis, the point prevalence rates summed to 9500 per 100,000 population. Even if we also excluded all headache, all trauma, all alcoholism, and all vertebrogenic pain states, 3.6% of the general population at any one time should be under neurologic care. Substracting all these exclusions from the incidence rates similarly leaves more than 1 person in every 100 who each year will have a new neurologic disorder that requires the attention of a physician competent in clinical neurology.     

Incidence and prevalence of juvenile chronic arthritis in East Berlin 1980-88

OBJECTIVE: To estimate the incidence and prevalence rates of juvenile chronic arthritis (JCA). METHODS: The study population was children under 16 years of age living in the East Berlin area (part of the former German Democratic Republic). By admission order that was effective up to 1990, all children with symptoms of a rheumatic disease living in the East Berlin area had to be referred to the 2nd Children's Hospital at Berlin-Buch. This specific condition allowed us to ascertain cases from the clinical records and to calculate population rates. Based upon this data, the results of surveys with different methods of case ascertainment are compared. RESULTS: An incidence rate of 3.5 per 100,000 and a prevalence rate of 2.0 per 10,000 children were calculated. The frequency of JCA is higher for girls, with an incidence of 4.3 per 100,000 and a prevalence of 2.3 per 10,000. The figures for boys are 2.7 per 100,000 and 1.7 per 10,000, respectively. CONCLUSION: Because of the specific prerequisites, the population rates of prevalence and incidence that were based on clinical records can be regarded as valid in this study. Deviant results of other surveys can be explained by differences in the study design or in the diagnostic procedures used.     

Blastomycosis in northeast Tennessee

STUDY OBJECTIVES: To study the epidemiologic and clinical features of blastomycosis in northeast Tennessee. DESIGN: Retrospective review of blastomycosis cases in the region from 1980 through 1995. SETTING: Hospitals located in the Tri-Cities region of northeast Tennessee. PATIENTS: Seventy-two patients with confirmed blastomycosis infection. INTERVENTIONS: None. RESULTS: During the 1980 to 1995 study period, we documented 72 cases of blastomycosis. The mean age was 52 years (range, 13 to 86 years), most were male (69.4%), and nine were immunocompromised. A possible environmental exposure was noted for 28 patients. Pulmonary involvement represented the most common site of infection (61 cases), but multiorgan involvement was common (17 cases). Most patients with pulmonary blastomycosis (66%) presented with a chronic illness, and radiologic findings usually revealed local consolidation or a mass-like lesion. Nine patients developed ARDS with an associated mortality rate of 89%, compared with a 10% mortality for non-ARDS pulmonary cases. Antifungal treatment regimens varied widely, with amphotericin B often used for sicker patients. An epidemiologic evaluation revealed that the mean yearly incidence rate for blastomycosis quadrupled between 1980 and 1987 (0.31 cases/ 100,000 population) and 1988 to 1995 (1.23 cases/100,000 population) (p=0.00001). Most new blastomycosis cases in the 1988 to 1995 period occurred in three counties in the region where significant new construction projects have been underway. CONCLUSION: Blastomycosis is endemic in northeast Tennessee and the number of cases is increasing, coinciding with major new construction in the region. Clinicians in the area must be alert to this condition.     

The risk of meningitis among classroom contacts during an epidemic of meningococcal disease

During an epidemic of meningococcal disease in Belo Horizonte, Brazil, a retrospective survey was carried out to assess the risk of meningitis associated with exposure in a schoolroom. Forty-seven of 17,012 students reportedly had meningitis in August-November 1974, an incidence of 276 per 100,000. Four of 1356 students with classroom exposure to a case contracted meningitis (secondary attack rate, 295 per 100,000). The results indicate that in the population surveyed, 95% of whom were from 7 to 14 years of age, there is no significantly increased risk associated with classroom exposure to a student with meningitis. Antibiotic prophylaxis of classroom contacts is therefore not indicated and should be reserved for contacts known to be at increased risk, such as members of the patient's household or those having direct contact with the patient's oral secretions.     

Tuberculosis in Australia: bacteriologically confirmed cases and drug resistance, 1996. Report of the Australian Mycobacterium Reference Laboratory Network

The Australian Mycobacterium Reference Laboratory Network collected and analysed laboratory data on new diagnoses of infection with Mycobacterium tuberculosis complex during 1996. A total of 750 cases were identified, representing an annual incidence of 4.1 cases of laboratory confirmed tuberculosis per 100,000 population. The incidence rate varied between States, reflecting differences in the distribution of persons belonging to 'high-risk' categories for tuberculosis. Incidence statistics were almost identical to those recorded by the Network in 1994 and 1995. The male:female ratio remained at around 1.2:1. As was the case in 1995, the median age group for males was 45-49 years and for females 35-39 years. The frequency of positive microscopy in pulmonary samples was stable at around 55%. Lymphatic disease accounted for 19% of the total cases in 1996 compared with 15% in the previous year, confirming that lymphadenitis is becoming more common in females with tuberculosis in Australia. Approximately 11% of isolates had in vitro resistance to at least one of the four standard anti-tuberculosis drugs, an increase from 8% in 1994-95. Fifteen isolates were multi-drug resistant, compared with a total of only 38 during the previous seven years. Thus, the 1996 data points to an increasing frequency of multi-drug resistant strains among isolates from Australian patients with tuberculosis.     

Sequence analysis of the putative viral enhancer in tissues from 33 cats with various feline leukemia virus-related diseases

INTRODUCTION: The incidence of shigellosis in Israel was fairly stable until around 1974, when it gradually began to increase to a peak in 1985. This was accompanied by a shift in the maximum incidence in the Jewish population from the age group < 1 to 1-4 years. AIM: To update the epidemiology of shigellosis in Israel 1986-1995. METHODS: Only laboratory-confirmed cases of shigellosis in the civilian population were analyzed. Data were obtained from the weekly reports of the subdistricts. Antibiotic sensitivity data were obtained from several hospitals and the General Workers' Sick Fund laboratories in Jerusalem, Haifa, and Tel Aviv. RESULTS: From 1986 to 1991, shigellosis incidence per 100,000 decreased by about 50%, and the decrease occurred mainly in the Jewish population. Several regional outbreaks in 1992 reversed this decline, but by 1995, the incidence was similar to that observed prior to 1974. The disease still occurs mainly in the summer, with an occasional winter outbreak. Higher incidence rates occurred in the northern subdistricts. The peak incidence in the non-Jewish population moved from the < 1-year-olds to the 1-4 year-old group, similar to the pattern in the Jewish population in 1970. In 1991, for the first time, the rate in the age group 5-9 years among non-Jews exceeded that of those < 1 year old. Marked decreases in sensitivity to several antibiotics were found in peripheral and hospital laboratories. An increase in the sensitivity to tetracycline was noted since 1991. Case fatality rates remain low, with a mean of 0.05% for the decade of the 1980s. CONCLUSIONS: Shigellosis remains a highly endemic disease in Israel, but changes in the age-related peak incidence indicate that the pattern of spread is becoming more similar to other developed countries.     

Incidence of non-melanocytic skin cancer in Geraldton, Western Australia

To measure the rate at which non-melanocytic skin cancers develop, we conducted a population-based, longitudinal study in Geraldton, Western Australia. Subjects were residents of Geraldton, Western Australia, who were between 40 and 64 years of age and registered on the electoral roll in 1987. In 1987 and again in 1992, dermatologists examined participants for skin cancers. They examined all skin areas, apart from those covered by underwear or hair. Subjects were asked about skin cancers that they had had treated between the 2 surveys. When all skin cancers were counted, the incidence rates of basal cell carcinoma were 3,379 per 100,000 person-years in women and 7,067 per 100,000 in men; those of squamous cell carcinoma were 501 per 100,000 in women and 775 per 100,000 in men. Sixteen percent of men and 14% of women developed at least one basal cell carcinoma; 2.8% of men and 2.2% of women had at least one squamous cell carcinoma. Most incident skin cancers were diagnosed at the second examination. More than half of the subjects who had a skin cancer at the first examination developed another. Squamous cell carcinomas occurred almost exclusively on parts of the body that are usually exposed. Basal cell carcinomas were common on the head, neck and trunk but not on the forearms and backs of hands. A quarter of people with a skin cancer on an exposed site also had one on the trunk. Our results show that skin cancer is extremely common in this population and frequently undiagnosed. Multiple skin cancers occur commonly, and skin cancers on exposed sites often are associated with skin cancers on less exposed sites.     

Demographic study of first-ever stroke and acute myocardial infarction in Okinawa, Japan

We performed a cross-sectional survey of stroke and acute myocardial infarction (AMI) in Okinawa, Japan with a census population of about 1.2 million. A total of 3,644 cases of first-ever stroke and 898 cases of initial acute myocardial infarction (AMI) were detected. The age-adjusted annual incidence rate for stroke was 105 per 100,000 standard population of Japan, and that of AMI was 26. The case-fatality rate of stroke within 28 days of onset was 12.8%, and that of AMI was 22.2%. Of the stroke cases, 51.4% were diagnosed as brain infarction, 38.7% as brain hemorrhage, and 9.3% as subarachnoid hemorrhage. The diagnosis of stroke subtypes were confirmed by computed tomography or magnetic resonance imaging in 98.4% of all stroke cases. In Okinawa, the incidence rate of AMI was still considerably lower than that in the Western population, and the rate of stroke was similar to that in the Western population.     

The manganese superoxide dismutase from the penicillin producer Penicillium chrysogenum

A survey was conducted to clarify the tuberculosis (TB) situation among the homeless during the period from 1991 to 1995 in Nagoya city, using 5,222 registration cards of TB cases registered at one of Nagoya City's 16 Health Centers. Out of 5,222 TB cases, there were 269 homeless cases (267 male and 2 female). Ninety-seven percent of them were pulmonary TB cases. The incidence and prevalence rates of TB per 100,000 among the homeless were estimated at around 1,500 and around 2,400, respectively, around 20 times higher than those of the non-homeless male over the 19 years of age. A decrease in the incidence rate of TB cases among the homeless was not seen, although the rate among the non-homeless decreased gradually. The percentage of infectious (bacillary and/or cavitary) tuberculous cases among the homeless was higher than in the non-homeless. In the infectious cases, the percentage of smear-positive bacillary cases or far advanced cavitary cases was 52.1% or 9.4% among the homeless compared to 48.1% or 2.6% among the non-homeless, respectively. The detection rate by chest X-ray examination of the homeless was 3.9%.     

Lights and shadows on the molecular diagnosis of hepatitis C

We undertook an epidemiologic study to ascertain the prevalence of multiple sclerosis (MS) in the Sanitary District of Calatayud, in the north-east of Spain. METHODS: The study was performed from October 1990 to July 1996. The total number of residents in the area was 58,591. An extensive search was carried out to identify all cases of known or suspected MS through general practitioners and specialists, sanitary authorities in the area, the reference hospital, the Spanish Multiple Sclerosis Society, the newspaper and radio. RESULTS: April 1, 1995 was chosen as prevalence day. The crude prevalence rate for the area was 58 per 100,000 (95% CI: 39-78). The approximate annual incidence rate was 2.6/100,000 (1980-1989). CONCLUSIONS: This study and others conducted recently in Spain show that MS is more prevalent than was previously thought and afflicts at least 53-65 per 100,000 population.     

Thyroid hormone resistance. Clinical, biochemical and genetic study of a family

OBJECTIVE: To investigate the incidence rate of IDDM in China. RESEARCH DESIGN AND METHODS: The Chinese IDDM registry was established in 1991 as part of the World Health Organization's Multinational Project for Childhood Diabetes (DiaMond) project. Twenty-two centers were developed to monitor the incidence of IDDM in children < 15 years of age. The population under investigation includes > 20 million individuals, representing approximately 7% of the children in China. Capture-recapture methods were used to estimate the ascertainment. RESULTS: The overall ascertainment-corrected IDDM incidence rate in China was 0.51 per 100,000, the lowest rate ever reported. There was a 12-fold geographic variation (0.13-1.61 per 100,000). In general, the incidence rate was higher in the north and the east. There was a sixfold difference among ethnic groups (highest: Mongol group, 1.82 per 100,000; lowest: Zhuang group, 0.32 per 100,000). CONCLUSIONS: China has an extremely low overall IDDM incidence rate. China also has the greatest geographic and ethnic variation seen for any country.     

Malignant mesothelioma: incidence, survival and relative risks in selected municipalities 1943-1992

The development in incidence rates and survival in Denmark, and the rate-ratio in selected municipalities that had industries utilizing asbestos was studied in 1865 cases of malignant mesothelioma identified in the Danish Cancer Registry 1943-1992. For men a steady increase in the incidence to 1.6 per 100,000 personyears in 1992 was found, while the rate for women decreased to 0.28 per 100,000 personyears. Age-specific incidence rates were highest for the older age-groups. An unexplained difference in the distribution of pleural and peritoneal cancers was seen between men and women. The average survival was 6.9 months for men and 7.8 for women and had not changed during the period of observation. The average rate-ratio for the selected municipalities was 1.97 (95% confidence intervals: 1.73-2.24) for men and 1.35 (1.08-1.69) for women. Improvements in working conditions in terms of minimizing asbestos exposure were introduced in 1980. Considering the latency period from exposure to diagnosis of 25-30 years, the impact of this measure on the rate of incidence cannot be expected before the year 2000.     

Snakebite mortality in Costa Rica

The mortality rate due to snakebite envenomation in Costa Rica was estimated from 1952 to 1993. The highest mortality was observed during the 1950s and 1960s, with the highest rate of 4.83 per 100,000 population in 1953. In contrast, a rate of 0.2 per 100,000 population per year was estimated from 1990 to 1993. The most conspicuous decline in mortality occurred after 1970. The highest mortality rates were observed in the provinces of Limón and Puntarenas, especially in regions where tropical rain forests had been transformed into agricultural fields. The lowest mortality was in the province of Guanacaste, where tropical dry forest predominates and Bothrops asper (terciopelo), the most important poisonous snake in the country, is not abundant. The majority of fatalities occurred in the age groups from 10 to 19 years old. Males were more affected than females in a ratio of 3.6:1. Before 1980 most fatal cases did not receive medical attention in hospitals, whereas after 1980 the majority of cases with fatal outcome were attended in hospitals.     

Clinical aspects of human Venezuelan equine encephalitis in Texas

The Venezuelan equine encephalitis epidemic which occurred in Texas in 1971 produced a wide range of predominantly mild clinical symptoms. This epidemic, which peaked on 13-14 July, was most intensely felt in the far-south counties of Cameron and Hidalgo. In all, 88 laboratory-confirmed human cases were reported to the U.S. Center for Disease Control by the Texas State Department of Health. The ratio of male to female cases was about two to one. An attack of 20.8 cases per 100,000, observed in both the 20-29 and 30-39 age groups, was higher than attack rates experienced by other age groups and by the population at large. Together, Cameron and Hidalgo counties experienced a much higher overall attack rate (21.7 cases por 100,000) than did affected counties in the Corpus Christi area (4.9 cases per 100,000). Knowledge about when various patients were first exposed points to an incubation period ranging from 27.5 hours to four days. In those 79 cases for which clinical data were available, the most common clinical manifestations were found to be fever, severe headache, myalgia, and chills. Evidence of mild to moderate central nervous system involvement was found in 10 out of 25 children and young people under 17 years of age, and in six out of 54 adults. Two children still had residual paralysis six weeks after onset of illness, but by 10 months these sequelae had disappeared. Seven of the 54 adults, however, still complained of tiring easily a year after onset of illness. Leukopenia, as demonstrated by a count of less rhan 4,500 white blood cells per cubic millimeter, was observed in 75 per cent of the patients examined.     

Monitoring of a whooping cough epidemic 1994/95 in Switzerland using the sentinel notification system. Sentinella Registry

Since June 1991 pertussis cases have been reported in the Swiss Sentinel Network (Sentinella). A total of 150-200 general practitioners, physicians specialized in internal medicine, and pediatricians participate in this system on a voluntary basis. Of the three specialties involved, this non-randomized sample represents 3.0%-3.5% of all physicians registered in Switzerland. The objective of this surveillance system is to monitor clinical pertussis over time. The case definition included all patients with a cough illness lasting at least 14 days with one of the following: paroxysms of cough, inspiratory "whoop", post-tussive vomiting (sporadic cases), or an epidemiological link to a pertussis case (epidemic cases). A laboratory diagnosis based on the polymerase chain reaction technique (PCR) was available for 82.7% of cases reported in 1994 and 1995. Of these, 27.7% had a positive PCR result. Reports of epidemic pertussis tested for Bordetella pertussis by PCR were confirmed by the laboratory in 46.5% of cases. The laboratory confirmation rate was more than twice as high among epidemic cases than among sporadic cases (20.7%). The crude incidence rate of whooping cough was 70 cases per 100,000 population per year in 1992 and 1993. Compared to previous years, pertussis incidence was significantly higher in 1994 and 1995 (370 cases per 100,000 population and 280 cases per 100,000 population respectively). The increase in reports was especially marked between July and October 1994 and whooping cough became epidemic in the third trimester of 1994 and at the beginning of 1995. In these 2 years, Switzerland experienced an estimated 40,000 clinical pertussis cases. Based on the proportion of PCR-positive pertussis cases in the sentinel sample, 12,500 of these would have been laboratory-confirmed. Most cases were observed in infants and in children up to 6 years of age. Assuming a vaccination coverage of 90%, the global efficacy of vaccination (3 or more doses versus less than 3) for 1994 and 1995 among children aged 12 to 47 months and not born before 1991 was 0.74 (0.59 and 0.88 for a vaccination coverage of 85% and 95% respectively). Vaccine efficacy was higher in PCR-positive cases (0.87; 0.79; 0.94) than in PCR-negative cases (0.54; 0.27; 0.78). Vaccination efficacy estimates on the basis of surveillance data are certainly less precise than those inferred from clinical trials. However, our results indicate that the efficacy of vaccination in children significantly declined with increasing age. Whooping cough still has the potential to cause epidemics in Switzerland in spite of a high vaccination coverage. With the introduction of acellular pertussis vaccines and new vaccination schemes in Switzerland, the Swiss Sentinel Network fulfills an important task as a monitoring system and contributes to the evaluation of new vaccination strategies.     

Tuberculosis in Australia: bacteriologically confirmed cases and drug resistance, 1994 and 1995. Report of the Australian Mycobacterium Reference Laboratory Network

The Australian Mycobacterium Reference Laboratory Network collected and analysed laboratory data on isolates of Mycobacterium tuberculosis reported during 1994 and 1995. The total number of confirmed isolates was 708 in 1994 and 705 in 1995. This represents an annual incidence of approximately 4 cases of laboratory confirmed tuberculosis per 100,000 population. These figures are similar to those reported in previous years and confirms that the incidence of tuberculosis in Australia remains stable. The incidence rate varied between States. Overall the male:female ratio fell, and there were signs of a downward shift in the median age. We were unable to assess the impact of HIV infection on the number of isolates reported. Positive microscopy was obtained in 55-60% of patients with pulmonary disease. Approximately 8% of isolates had in vitro resistance to at least one of the four standard anti-tuberculosis drugs. Over the two year period seven strains were found to be multi-drug resistant. Overall, the data from 1994-1995 gives no indication of a significant change in the drug susceptibility profiles of isolates from Australian patients with tuberculosis.     

Current trends of the epidemiology of human trichinosis in Chile

Surveillance of the epidemiology of human trichinosis in Chile has been maintained during the last 30 years by the Department of Parasitology. Incidence and prevalence have been followed-up by analysing Ministry of Health annual reports and periodical phototrichinoscopic examination of diaphragm samples from individuals autopsied at the Santiago Medico Legal Service. A decrease has been observed on: incidence from 1.4 per 100,000 in the 1960s to 0.7 in the 1980s down to 0.3 in 1993 and 1994 and to 0.5 in 1995, and prevalence from 3.4% to 2.8%, 2.0% and 0.8% in 1972, 1982, 1992 and 1997 respectively. A predominance of the prevalence in the groups of more age, with the observation of calcified Trichinella spiralis larvae should be indicating a decline of new infections in the general population. This decrease of frequency of human trichinosis in Chile is possible due to the interaction of two main factors, efficacy and higher implementation of control measures and significant advances in porcine technology with a resulting provision to consumers of pork from young animals practically trichinosis free.