Comparative study of the clinical manifestations and pathophysiology of leptospirosis and scrub typhus

The study aims were to determine the prevalence of leptospirosis and scrub typhus in northeast Thailand, and to compare and contrast their clinical features and outcomes. Leptospirosis and scrub typhus accounted for 45% of acute febrile illness in 1249 prospectively studied patients presenting to Udon Thani hospital , northeast Thailand between October 2000 and December 2002, nearly 20% of who has leptospirosis and scrub typhus coinfection. A total of 311 patients had leptospirosis, 97 of who were culture-positive for Leptospira spp. The culture-positive group had fewer complications, including aseptic meningitis, jaundice, renal impairment, thrombocytopenia and pulmonary haemorrhage, compared with the culture-negative group. A total of 304 patients were diagnosed as having scrub typhus, one-fourth of who had putative reinfection based on the presence of an IgG response without detectable IgM. Patients with primary scrub typhus infection were significantly younger and presented to hospital later than patients with reinfection. Primary infection was associated with jaundice, liver impairment and gastrointestinal bleeding, but fewer patients had shock and confusion compared with patients with reinfection. Patients with leptospirosis had significantly more hepatic and renal impairment, thrombocytopenia and bleeding diathesis than patients with scrub typhus. Despite this, the morality rate was comparable at around 3% for each infection, and the major cause of death for both disease was pulmonary haemorrhage. Patients with concurrent leptospirosis and scrub typhus had more severe clinical features (shock, jaundice, renal failure, thrombocytopenia and bleeding diathesis) than patients with one of these diseases alone, but mortality was comparable. A leptospirosis-scrub typhus (LEST) score based on clinical features and routine laboratory tests was developed to predict the diagnosis of leptospirosis or scrub typhus. The score specificity approached 90% for both diseases. Further validation of the LEST score is required to determine its accuracy in routine clinical practice and in other geographic areas

Comparison of the estimated incidence of acute leptospirosis in the Kilimanjaro Region of Tanzania between 2007-08 and 2012-14

Background: The sole report of annual leptospirosis incidence in continental Africa of 75–102 cases per 100,000 population is from a study performed in August 2007 through September 2008 in the Kilimanjaro Region of Tanzania. To evaluate the stability of this estimate over time, we estimated the incidence of acute leptospirosis in Kilimanjaro Region, northern Tanzania for the time period 2012–2014. Methodology and Principal Findings: Leptospirosis cases were identified among febrile patients at two sentinel hospitals in the Kilimanjaro Region. Leptospirosis was diagnosed by serum microscopic agglutination testing using a panel of 20 Leptospira serovars belonging to 17 separate serogroups. Serum was taken at enrolment and patients were asked to return 4–6 weeks later to provide convalescent serum. Confirmed cases required a 4-fold rise in titre and probable cases required a single titre of ≥800. Findings from a healthcare utilisation survey were used to estimate multipliers to adjust for cases not seen at sentinel hospitals. We identified 19 (1.7%) confirmed or probable cases among 1,115 patients who presented with a febrile illness. Of cases, the predominant reactive serogroups were Australis 8 (42.1%), Sejroe 3 (15.8%), Grippotyphosa 2 (10.5%), Icterohaemorrhagiae 2 (10.5%), Pyrogenes 2 (10.5%), Djasiman 1 (5.3%), Tarassovi 1 (5.3%). We estimated that the annual incidence of leptospirosis was 11–18 cases per 100,000 population. This was a significantly lower incidence than 2007–08 (p<0.001). Conclusions: We estimated a much lower incidence of acute leptospirosis than previously, with a notable absence of cases due to the previously predominant serogroup Mini. Our findings indicate a dynamic epidemiology of leptospirosis in this area and highlight the value of multi-year surveillance to understand leptospirosis epidemiology

Risk factors for human acute leptospirosis in northern Tanzania

Introduction: Leptospirosis is a major cause of febrile illness in Africa but little is known about risk factors for human infection. We conducted a cross-sectional study to investigate risk factors for acute leptospirosis and Leptospira seropositivity among patients with fever attending referral hospitals in northern Tanzania. Methods: We enrolled patients with fever from two referral hospitals in Moshi, Tanzania, 2012–2014, and performed Leptospira microscopic agglutination testing on acute and convalescent serum. Cases of acute leptospirosis were participants with a four-fold rise in antibody titers, or a single reciprocal titer ≥800. Seropositive participants required a single titer ≥100, and controls had titers <100 in both acute and convalescent samples. We administered a questionnaire to assess risk behaviors over the preceding 30 days. We created cumulative scales of exposure to livestock urine, rodents, and surface water, and calculated odds ratios (OR) for individual behaviors and for cumulative exposure variables. Results: We identified 24 acute cases, 252 seropositive participants, and 592 controls. Rice farming (OR 14.6), cleaning cattle waste (OR 4.3), feeding cattle (OR 3.9), farm work (OR 3.3), and an increasing cattle urine exposure score (OR 1.2 per point) were associated with acute leptospirosis. Conclusions: In our population, exposure to cattle and rice farming were risk factors for acute leptospirosis. Although further data is needed, these results suggest that cattle may be an important source of human leptospirosis. Further investigation is needed to explore the potential for control of livestock Leptospira infection to reduce human disease

ASPIRE-2-PREVENT: a survey of lifestyle, risk factor management and cardioprotective medication in patients with coronary heart disease and people at high risk of developing cardiovascular disease in the UK.

OBJECTIVE: To determine in patients with coronary heart disease (CHD) and people at high risk of developing cardiovascular disease (CVD) whether the Joint British Societies' guidelines on CVD prevention (JBS2) are followed in everyday clinical practice. DESIGN: A cross-sectional survey was undertaken of medical records and patient interviews and examinations at least 6 months after the recruiting event or diagnosis using standardised instruments and a central laboratory for measurement of lipids and glucose. SETTINGS: The ASPIRE-2-PREVENT survey was undertaken in 19 randomly selected hospitals and 19 randomly selected general practices in 12 geographical regions in England, Northern Ireland, Wales and Scotland. PATIENTS: In hospitals, 1474 consecutive patients with CHD were identified and 676 (25.6% women) were interviewed. In general practice, 943 people at high CVD risk were identified and 446 (46.5% women) were interviewed. RESULTS: The prevalence of risk factors in patients with CHD and high-risk individuals was, respectively: smoking 14.1%, 13.3%; obesity 38%, 50.2%; not reaching physical activity target 83.3%, 85.4%; blood pressure ≥130/80 mm Hg (patients with CHD and self-reported diabetes) or ≥140/85 mm Hg (high-risk individuals) 46.9%, 51.3%; total cholesterol ≥4 mmol/l 52.6%, 78.7%; and diabetes 17.8%, 43.8%. CONCLUSIONS: The potential among patients with CHD and individuals at high risk of developing CVD in the UK to achieve the JBS2 lifestyle and risk factor targets is considerable. CVD prevention needs a comprehensive multidisciplinary approach, addressing all aspects of lifestyle and risk factor management. The challenge is to engage and motivate cardiologists, physicians and other health professionals to routinely practice high quality preventive cardiology in a healthcare system which must invest in prevention

A serological survey of eight infectious diseases in a population of free ranging deer (Cervus timorensis russa) in Mauritius

Rusa deer (Cervus timorensis russa) is the most important red meat production of Mauritius. More than 70.000 heads are exploited annually for 440 tones of venison. This survey was undertaken in 2007 in order to update the status of the Mauritian deer population for eight infectious diseases, since no systematic health survey had been performed in the last ten years. A total of 369 deer from 28 extensive herds were randomly sampled during hunting operations. Male deer were more represented than females whereas the age distribution was balanced. Positive results were found for bovine tuberculosis (one case of Mycobacterium bovis, macrocospical examination and PCR confirmation), Johne's disease (1.7%, n=351, indirect ELISA and PCR confirmation), cowdriosis (95.5%, n=178, IFAT), leptospirosis (25.9%, n=363, MAT), bluetongue (4.1%, n=369, competitive ELISA), and EHD (1.3%, n=369, indirect ELISA). Negative results were found for Brucella abortus (n=355, indirect ELISA; n=99, Rose Bengal Test) and Rift Valley Fever Virus (n=88, indirect ELISA). Those results are the first for Johne's disease, leptospirosis, and bluetongue and EHD in Rusa deer in Mauritius. They also confirmed the maintenance of bovine tuberculosis and cowdriosis in the deer population since the 1980's and the probable absence of Brucella abortus osis and Rift Valley Fever Virus. This survey provided evidence of the need to monitor the health of farmed wildlife more regularly in order to detect zoonosis, infectious diseases of livestock and initiate an eradication program with the long term goal of certifying healthy farms and export venison overseas. (Résumé d'auteur

Cultural imagery and statistical models of the force of mortality: Addison, Gompertz and Pearson

We describe selected artistic and statistical depictions of the force of mortality (hazard or mortality rate), which is a concept that has long preoccupied actuaries, demographers and statisticians. We provide a more graphic form for the force-of-mortality function that makes the relationship between its constituents more explicit. The 'Bridge of human life' in Addison's allegorical essay of 1711 provides a particularly vivid image, with the forces depicted as external. The model that was used by Gompertz in 1825 appears to treat the forces as internal. In his 1897 essay Pearson mathematically modernized 'the medieval conception of the relation between Death and Chance' by decomposing the full mortality curve into five distributions along the age axis, the results of five 'marksmen' aiming at the human mass crossing this bridge. We describe Addison's imagery, comment briefly on Gompertz's law and the origin of the term 'force of mortality', describe the background for Pearson's essay, as well as his imagery and statistical model, and give the bridge of life a modern form, illustrating it via statistical animation

Association between footwear use and neglected tropical diseases: a systematic review and meta-analysis

BACKGROUND The control of neglected tropical diseases (NTDs) has primarily focused on preventive chemotherapy and case management. Less attention has been placed on the role of ensuring access to adequate water, sanitation, and hygiene and personal preventive measures in reducing exposure to infection. Our aim was to assess whether footwear use was associated with a lower risk of selected NTDs. METHODOLOGY We conducted a systematic review and meta-analysis to assess the association between footwear use and infection or disease for those NTDs for which the route of transmission or occurrence may be through the feet. We included Buruli ulcer, cutaneous larva migrans (CLM), leptospirosis, mycetoma, myiasis, podoconiosis, snakebite, tungiasis, and soil-transmitted helminth (STH) infections, particularly hookworm infection and strongyloidiasis. We searched Medline, Embase, Cochrane, Web of Science, CINAHL Plus, and Popline databases, contacted experts, and hand-searched reference lists for eligible studies. The search was conducted in English without language, publication status, or date restrictions up to January 2014. Studies were eligible for inclusion if they reported a measure of the association between footwear use and the risk of each NTD. Publication bias was assessed using funnel plots. Descriptive study characteristics and methodological quality of the included studies were summarized. For each study outcome, both outcome and exposure data were abstracted and crude and adjusted effect estimates presented. Individual and summary odds ratio (OR) estimates and corresponding 95% confidence intervals (CIs) were calculated as a measure of intervention effect, using random effects meta-analyses. PRINCIPAL FINDINGS Among the 427 studies screened, 53 met our inclusion criteria. Footwear use was significantly associated with a lower odds of infection of Buruli ulcer (OR=0.15; 95% CI: 0.08-0.29), CLM (OR=0.24; 95% CI: 0.06-0.96), tungiasis (OR=0.42; 95% CI: 0.26-0.70), hookworm infection (OR=0.48; 95% CI: 0.37-0.61), any STH infection (OR=0.57; 95% CI: 0.39-0.84), strongyloidiasis (OR=0.56; 95% CI: 0.38-0.83), and leptospirosis (OR=0.59; 95% CI: 0.37-0.94). No significant association between footwear use and podoconiosis (OR=0.63; 95% CI: 0.38-1.05) was found and no data were available for mycetoma, myiasis, and snakebite. The main limitations were evidence of heterogeneity and poor study quality inherent to the observational studies included. CONCLUSIONS/SIGNIFICANCE Our results show that footwear use was associated with a lower odds of several different NTDs. Access to footwear should be prioritized alongside existing NTD interventions to ensure a lasting reduction of multiple NTDs and to accelerate their control and elimination. PROTOCOL REGISTRATION PROSPERO International prospective register of systematic reviews CRD42012003338