Total Disease Prevalence Research Articles

Abstract 17187: Misinterpretation of Q-waves in Ventricular Septal Defect and Tetralogy of Fallot Patients by Non-Adult Congenital Heart Disease Specialists

Introduction: Tetralogy of Fallot (TOF) and Ventricular Septal Defect (VSD) patients have non-diagnostic Q-waves within inferior (II, III, aVF) or septal (V1-V2) leads on ECG, perhaps due to incomplete conduction through septal defects. Non-diagnostic Q-waves tend to either be wide within a single lead, or deep (3-4mm) in contiguous leads, but do not meet diagnostic criteria for infarct. Hypothesis: Non-Adult Congenital Heart Disease (ACHD) physicians may inaccurately characterize non-diagnostic Q-waves as pathologic opposed to expert interpretation by ACHD-trained physicians in VSD and TOF patients. Thus, misinterpreting ECGs to suggest prior infarct and decreasing their positive predictive value (PPV). Methods: With application of pre-specified inclusion and exclusion criteria, we retrospectively reviewed 72 ECGs from TOF or VSD patients at Penn State Hershey Medical Center from 2002-2020 that were separately read by ACHD and non-ACHD specialists. Primary outcomes were ECGs with diagnosed Q-waves in two separate distributions, inferior or septal leads, by both groups using standard criteria for Q-wave infarct. Reported measures were sensitivity, specificity, PPV, and negative predictive value (NPV). Results: The 72 subjects with isolated TOF or VSD had a mean age of 39 years and 63% were male. Total disease prevalence (presence of Q-waves) was 4.6%. Q-wave infarct diagnosed by non-ACHD physicians had a sensitivity and specificity of 33% and 74% respectively. Their PPV was 5.87% and NPV was 95.85%. Conclusions: This retrospective cohort analysis of TOF and VSD patient ECGs showed the low PPV of non-ACHD physician diagnosis of Q-waves in this respective population. Misinterpretation and misdiagnosis of infarct based off ECG, has ramifications for both the patient and medical system as a whole. Sequelae include, but are not limited to, increasing patient risk for unwarranted medical treatment and affecting hospital billing and insurance coverage.

The association between coral communities and disease assemblages in the Wakatobi Marine National Park, south-eastern Sulawesi, Indonesia

The relationship between coral community structure and disease prevalence is poorly understood, particularly in the Coral Triangle. Improved understanding of this relationship will assist in identifying assemblages that might be particularly vulnerable to disease, and in predicting possible future impacts. Here, we report results from the last 2 years (2010 and 2011) of a 4-year coral disease-monitoring program (2005, 2007, 2010, 2011) in the Wakatobi Marine National Park (Indonesia), and evaluate changes in total disease prevalence and coral cover since 2005. A comparison with previously published results from 2005 and 2007 indicates that the number of coral diseases increased from two to eight and total disease prevalence tripled between 2005 and 2011. We observed a dramatic decline in coral cover and an increase in disease prevalence at a site with a unique community of foliose corals. However, because of the 3-year period between surveys (2007, 2010), it is likely that the peak of the disease event was not observed. While multi-year studies provide useful insights into the relationships between community structure and disease, our results emphasise how determining the drivers of change in remote reef locations is especially challenging if events such as disease outbreaks are missed.

A structured avian influenza model with imperfect vaccination and vaccine-induced asymptomatic infection.

We introduce a model of avian influenza in domestic birds with imperfect vaccination and age-since-vaccination structure. The model has four components: susceptible birds, vaccinated birds (stratified by vaccination age), asymptomatically infected birds, and infected birds. The model includes reduction in the probability of infection, decreasing severity of disease of vaccinated birds and vaccine waning. The basic reproduction number, [Formula: see text], is calculated. The disease-free equilibrium is found to be globally stable under certain conditions when [Formula: see text]. When [Formula: see text], existence of an endemic equilibrium is proved (with uniqueness for the ODE case and local stability under stricter conditions) and uniform persistence of the disease is established. The inclusion of reduction in susceptibility of vaccinated birds, reduction in infectiousness of asymptomatically infected birds and vaccine waning can have important implications for disease control. We analytically and numerically demonstrate that vaccination can paradoxically increase the total number of infected, resulting in the "silent spread" of the disease. We also study the effects of vaccine efficacy on disease prevalence and the minimum critical vaccination coverage, a threshold value for vaccination coverage to avoid an increase in total disease prevalence due to asymptomatic infection.

Distribution and prevalence of coral diseases in the Veracruz Reef System, Southern Gulf of Mexico

Ten reefs of the Veracruz Reef System (VRS) were surveyed to evaluate the distribution and prevalence of diseases that affect stony corals. Total disease prevalence on corals in the VRS was 4.8%. Seven diseases affecting 6 coral genera (4 of which are the most abundant) were observed in 85.2% of the evaluated sites. As observed in other reefs of the Caribbean, dark spots disease had the highest prevalence (2.9%) and widest distribution. The incidence of disease showed a patchy distribution, with prevalence being significantly higher on the reef flats than on the windward and leeward sides.

Coral disease in Micronesian reefs: a link between disease prevalence and host abundance

Current information regarding the effects of coral diseases on Indo-Pacific reefs lags behind that of the Caribbean. Considering that these reefs are geographically widespread, speciose, often highly influenced by human coastal populations, and inadequately monitored, developing a baseline database is a primary management issue for local scientists. In a first attempt to quantify diseases in Micronesia, Guam reefs were assessed for disease prevalence, host abundance, and community structure. Surveys of 15 reefs revealed 6 disease states affecting 8 families of reef-building corals and highly variable prevalence between sites, ranging from 0.2 to 12.6%. Guam reefs are taxonomically diverse but dominated by the genus Porites. Coral generic host abundance showed a significant and positive link with total disease prevalence. Five out of 6 of the observed disease states affected Porites spp. (mean prevalence within the genus: 6.14 +/- 0.88%), and acroporids and pocilloporids also showed high susceptibility. As the coral genera currently most affected by diseases are those providing the most structure to Guam's reefs, disease has the potential to have significant long-term effects, highlighting an urgent need for proactive management.

Spatio-temporal coral disease dynamics in the Wakatobi Marine National Park, South-East Sulawesi, Indonesia

In the present study we investigated inter-annual coral disease dynamics, in situ disease progression rates, and disease-associated coral tissue mortality in the Wakatobi Marine National Park (WMNP) situated in the coral triangle in South-East Sulawesi, Indonesia. In 2005, only 2 known syndromes were recorded within the sampling area transect surveys: white syndrome (WS; 0.42% prevalence) and growth anomalies (GA; 0.15% prevalence), whilst 4 diseases were recorded in 2007: WS (0.19%), Porites ulcerative white spot disease (PUWS; 0.08%), GA (0.05%) and black band disease (BBD; 0.02%). Total disease prevalence decreased from 0.57% in 2005 to 0.33% in 2007. In addition to prevalence surveys, in situ progression rates of 4 diseases were investigated in 2007: BBD on Pachyseris foliosa, P. rugosa and Diploastrea heliopora, WS on Acropora clathrata, and brown band (BrB) and skeletal eroding band (SEB) diseases on Acropora pulchra. BrB and WS had the highest progression rates, 1.2 +/- 0.36 and 1.1 +/- 0.07 cm d(-1), respectively, indicating that diseases may have a significant impact on local Acropora populations. BBD had the lowest progression rate (0.39 +/- 0.14 cm d(-1)). WS caused the most severe recorded total tissue mortality: 53 923 cm2 over a period of 36 d. Sedimentation and coral cover were studied and a highly significant drop in coral cover was observed. This study provides the first documentation of spatio-temporal coral disease dynamics from Indonesia. Despite low total disease prevalence, progression rates comparable to the ones observed in the Caribbean and Australia indicate that diseases may threaten the reef framework in some locations and add to the degradation of coral reefs in a region already at high risk from anthropogenic impacts.

A Two–Film versus a Four–Film Bite–Wing Examination for Caries Diagnosis in Adults

The aim of this study was to compare the caries diagnostic outcome of a two–film and a four–film routine bite–wing examination undertaken in an adult population. A digital bite–wing examination using two and four films, respectively, was performed in 174 patients. The radiographs from the two examinations were assessed jointly by 2 observers for the number of imaged surfaces in the area from the distal surface of the canine to the distal surface of the third molar and for the detection of carious lesions. Significantly more surfaces were available for examination by the four–film than by the two–film examination. Overlapping surfaces were recorded in 14 and 10%, respectively, of the surfaces imaged by the two–film and four–film set. The prevalence of primary enamel and dentinal caries was 6.8% with the two–film and 5.6% with the four–film method. In 1,684 surfaces only imaged by the four–film method caries was detected in 20 surfaces. If these extra lesions were added to the number of lesions found by the two–film method the total disease prevalence using the last–mentioned method would increase by 2‰. The majority (92–99%) of all recorded lesions were detected in surfaces located between the occlusal surface of the first premolar and the mesial surface of the third molar. The little additional diagnostic outcome obtained by the use of four instead of two films did not seem to match the extra resources (double patient charge and radiation dose, and extended scan/developing and recording time for the dentist) connected to the four–film method. Thus, it may be recommended that a routine bite–wing examination undertaken in young adults should be performed with only two films: one in each side of the mouth, placed behind the premolars and the first and second molars.

Systemic sclerosis prevalence and mortality in Sydney 1974-88.

Systemic sclerosis prevalence and mortality estimates have demonstrated wide variability. The sole Australian study published to date demonstrated high prevalence rates when compared to overseas estimates. The prevalence and mortality findings reported in this paper derive from a larger study which addressed the distribution and determinants of systemic sclerosis within Sydney. To determine systemic sclerosis prevalence and mortality rates within Sydney over 15 years, 1974-88. Cases were ascertained from multiple sources including death certificates, hospitals, physicians, vascular surgeons' and dermatologists' private practices, a systemic sclerosis self-help group and private medical laboratories. Overall, 715 cases were identified. Females comprised 77% (95% CI: 74-80) of cases. Disease of the limited subtype accounted for 79% (95% CI: 76-82) of all systemic sclerosis, being relatively more frequent in living than deceased cases, and in females than males. Crude prevalence estimates appeared to rise between 1975 (4.52/100,000 95% CI:3.75-5.29/100,000) and 1988 (8.62/100,000 95% CI:7.64-9.60/100,000) as did estimates of diffuse disease. However, diffuse disease prevalence, when expressed as a proportion of total disease prevalence, showed no significant temporal change. Although crude mortality rates also showed apparent temporal increases (0.24/100,000 in 1975 to 0.80/100,000 in 1988) standardised mortality rates showed less convincing trends (0.41/100,000 in 1976 and 0.40/100,000 in 1988). Death certificate-derived mortality rates provided relatively large underestimates of total mortality. However, these underestimates were relatively constant over time. This study has demonstrated systemic sclerosis prevalence and mortality rates comparable to overseas estimates, consistently higher prevalence and mortality rates in females than males, proportionally higher rates of diffuse disease in males than females and in deceased cases than living cases, a diffuse: limited disease ratio apparently stable over time, apparently increasing temporal prevalence and mortality rates and, by implication, rising incidence rates. The observed temporal rise in diffuse disease prevalence and the absence of a convincing fall in diffuse disease mortality suggests a rising temporal incidence rate of diffuse disease. Standardised mortality rates demonstrated less consistent trends than did crude mortality rates and failed to demonstrate convincing declines in mortality subsequent to the introduction of ACE inhibitors for management of systemic sclerosis renal disease. Death certificate-derived systemic sclerosis mortality rates considerably and consistently underestimated systemic sclerosis-all cause mortality.

Linkage analysis of candidate loci in families with recurrent major depression.

Recurrent major depression, RMD, is characterized by the occurrence of depressive episodes in the absence of mania and/or hypomania. In linkage studies, RMD (or, in general, unipolar depression) are frequently grouped together with bipolar illnesses into a broad definition of affective disorders. However, twin studies suggest that RMD and bipolar disorders might have different genetic determinants. The objective of this study was to test a set of families with RMD for linkage to chromosomes that have been recently proposed to contain susceptibility loci for bipolar disorders: chromosomes 16, 18, 21 and the short arm of chromosome 4. We analysed five large families from the northern part of Sweden ascertained through a proband with RMD and containing several patients with RMD. For the genetic analysis, we included only severely affected individuals (those who had at least three episodes that required medical treatment) to increase the chances of finding a larger degree of genetic determination. The genetic model led to a total disease prevalence of 5% in females and 3% in males. We did not find significant evidence for linkage to any of the candidate chromosomes in the combined family set. Only one of the families showed a slight indication for linkage with markers from the pericentromeric region of chromosome 18. A genome scan analysis on an extended collaborative family material with severely affected individuals with RMD should be performed to evaluate whether RMD and bipolar disorders have a different genetic etiology.

Dynamics of fish diseases in the lower Elbe River

As part of a survey on population dynamics and ecology of fishesin the Elbe River, seasonal and regional fluctuations of external fish diseases were studied from the open North Sea to Hamburg in 1981–1982. Clinical signs of 11 different diseases, several of them not being recorded before, were noted in 22 fish species. Averaged over all samples, the total disease prevalence was below 1 % in 16 species. Highest prevalences were found in smelt (12.7 %), eel (9.2 %), and flounder (5.5 %). The frequency of most diseases increased in larger (older) fish. High prevalences of skeletal abnormalities in cod could be related to abnormal migration habits of diseased fish. Spawning papillomatosis, skin ulceration, and fin rot in smelt occurred predominantly during the spawning season. Most diseases observed occurred at relatively high prevalences in the central Elbe estuary between Cuxhaven and Brunsbuttel. This is most obvious for lymphocystis, fin rot, skin ulceration, and bleaching syndrome in flounder, but such a tendency also seems to occur in cauliflower disease of eel, as well as spawning papillomatosis and pharyngeal granuloma in smelt. This area is less heavily polluted and less frequently affected by oxygen deficiency than the area upstream of Gluckstadt, where diseases in general occurred at lower frequencies. Therefore, it is concluded that neither pollution nor lack of oxygen are the main triggers for the outbreak of diseases in Elbe fish. It is supposed that large tidal fluctuations of salinity are a major stress factor for fish in the estuary between Cuxhaven and Brunsbuttel. Flounder from this area usually are in a relatively bad nutritional state. Their condition factor increases significantly towards Hamburg, while their disease prevalence decreases in the same direction.