Rabies control in KwaZulu-Natal, South Africa.

PROBLEM: Urbanization, large dog populations and failed control efforts have contributed to continuing endemicity of dog-mediated rabies in KwaZulu-Natal province, South Africa. APPROACH: From 2007 to 2014 we used a OneHealth approach to rabies prevention, involving both the human and animal health sectors. We implemented mass vaccination campaigns for dogs to control canine rabies, and strategies to improve rabies awareness and access to postexposure prophylaxis for people exposed to rabies. LOCAL SETTING: A rabies-endemic region, KwaZulu-Natal is one of the smallest and most populous South African provinces (estimated population 10 900 000). Canine rabies has persisted since its introduction in 1976, causing an average of 9.2 human rabies cases per annum in KwaZulu-Natal from 1976 to 2007, when the project started. RELEVANT CHANGES: Between 2007 and 2014, the numbers of dog vaccinations rose from 358 611 to 395 000 and human vaccines purchased increased form 100 046 to 156 996. Strategic dog vaccination successfully reduced rabies transmission within dog populations, reducing canine rabies cases from 473 in 2007 to 37 in 2014. Actions taken to reduce the incidence of canine rabies, increase public awareness of rabies and improve delivery of postexposure prophylaxis contributed to reaching zero human rabies cases in KwaZulu-Natal in 2014. LESSONS LEARNT: Starting small and scaling up enabled us to build strategies that fitted various local settings and to successfully apply a OneHealth approach. Important to the success of the project were employing competent, motivated staff, and providing resources, training and support for field workers.

Towards Canine Rabies Elimination in KwaZulu-Natal, South Africa: Assessment of Health Economic Data.

Rabies remains a significant problem throughout much of the developing world. An estimated 69 000 people die annually from exposure to rabies. Most of these deaths are the result of being bitten by a rabid dog. Mass vaccination campaigns targeting dogs have been implemented around the world in an attempt to control or eliminate canine rabies. We analysed the vaccination and cost data for a campaign in the KwaZulu-Natal province of South Africa; we found that the cost per dog vaccinated to be $6.61 for mass campaigns and $5.41 for local campaigns. We also estimated the cost of human post-exposure prophylaxis (PEP). The cost of PEP is approximately $64.50 on average per patient, and $333 on average for the 9% of patients who receive RIG. We also found that the districts that vaccinated the most dogs per capita experienced the highest rates of human treatment and thus had the highest PEP costs.

Effect of manufacturer-inserted mask leaks on ventilator performance.

Most pressure-support devices use a single circuit with an exhalation port integrated in the mask. The aim of the current study was to compare the effects of masks having different manufacturer-inserted leaks on ventilator performance. We simulated chronic obstructive pulmonary disease and restrictive disease. Four ventilators (VENTImotion (Weinmann, Hamburg, Germany), VPAP III STA (ResMed, Saint Priest, France), Synchrony 2 (Respironics, Nantes, France) and Vivo 40 (Breas, Saint Priest)) were tested with the recommended masks and with the masks having the largest and smallest leaks. Tests were performed with pressure support levels of 10, 15 and 20 cmH(2)O. The in vivo evaluation compared two ventilators using recommended masks opposed in terms of exhaled port resistance. The ventilators were tested with their recommended mask, and after mask exchange. The mask with the largest leak induced auto-triggering and/or increased inspiratory-trigger sensitivity was the VENTImotion under both simulated conditions and VPAP III STA under the simulated obstructive-disease condition. The mask with the smallest leak-increased inspiratory-trigger delay was Synchrony 2 in the simulated obstructive-disease condition and increased rebreathing. The in vivo study confirmed the bench results. When switching to a mask that has a different leak, evaluation is needed to adjust trigger sensitivity and pressurisation level and to check the absence of rebreathing.

Effect of sleeping alone on sleep quality in female bed partners of snorers.

The aim of the present study was to objectively measure the effect of sleeping alone for one night on sleep quality in female bed partners of male snorers. Females complaining of poor sleep due to snoring by their bed partner and having no known hearing loss or snoring were included in a prospective multicentre cross-sectional study. 23 females underwent one polysomnography recording while sleeping with their bed partner and another while sleeping alone. Their sleep parameters were compared between the two nights. We excluded seven couples because the female partner snored for >10% of the sleep time (n = 6) or had obstructive sleep apnoea syndrome (n = 1). In the remaining 16 females, sleep time, sleep efficiency, arousal index and percentages of deep sleep (stages 3-4) and rapid eye movement (REM) sleep were not significantly different between the two nights. Percentages of light sleep (non-REM stage 2) and awakening index were lower when sleeping alone (p = 0.023 and p = 0.046, respectively). Sleep quality was decreased and sleep fragmentation increased in females sleeping with male snorers. Some females had unrecognised snoring. However, our data do not suggest that objective sleep quality improves substantially in the female nonsnoring partner when she sleeps alone for one night.

Kinetics modeling of alginate alkaline extraction from Laminaria digitata.

Alginates being depolymerized during their alkaline extraction, reducing extraction time could help producing higher rheological quality alginates. The purpose of the present work is to study fresh Laminaria digitata destructuration during alkaline extraction and its link to extraction kinetics. Both alginate extraction yield and mean diameter of algae particles were followed for different values of agitation level and initial size of algae pieces. Results highlighted the existence of a link between extraction yield and algal destructuration. Those elements and the specificity of L.digitata structure have been taken into account to propose a kinetics model based on a fluid-particle reaction with decreasing size particles. The model parameters have been adjusted thanks to acquisition data and its predictive capacity was assessed by validation data. Provided predictions appeared to be relevant and the model structure suitability was confirmed, as extraction yield kinetics specific shape was quite reliably described.

Performance of ventilators for noninvasive positive-pressure ventilation in children.

The aim of the present study was to evaluate the performance characteristics of all the ventilators proposed for home noninvasive positive-pressure ventilation in children in France. The ventilators (one volume-targeted, 12 pressure-targeted and four dual) were evaluated on a bench which simulated six different paediatric ventilatory patterns. For each ventilator, the quality of the inspiratory and expiratory trigger and the ability to reach and maintain the preset pressures and volumes were evaluated with the six patient profiles. The performance of the ventilators showed great variability, and depended upon the type of trigger (flow or pressure), type of circuit and patient profile. Differences were observed between the preset and measured airway pressure and between the tidal volume measured by the ventilator and on the bench. Leaks were associated with an inability to detect the patient's inspiratory effort or autotriggering. No single ventilator was able to adequately ventilate the six paediatric profiles. Only a few ventilators were able to ventilate the profiles simulating the youngest patients. A systematic paediatric bench evaluation is recommended for every ventilator proposed for home ventilation, in order to detect any dysfunction and guide the choice of the appropriate ventilator for a specific patient.

Characteristics of tracheostomy phonation valves.

Phonation valves are commonly used devices that allow the restoration of speech in tracheostomised patients. However, their use should not compromise the physiological benefit of tracheostomy. Six commercialised phonation valves were studied in a dynamic set-up simulating a respiratory frequency of 20 breaths.min(-1), a tidal volume of 0.5 L and a peak flow rate of 0.5 L.s(-1). Resistance and additional work of breathing (WOB) were calculated. In 10 tracheostomised patients, evaluations using no phonation valve (baseline), and the most and one of the least resistive valves were carried out. Respiratory patterns and gas exchanges were recorded. Inspiratory difficulty was evaluated using the modified Borg scale. Valves displayed a wide array of resistance ranging 1.3-5.9 cmH2O.L(-1).s(-1). Additional WOB varied with a ratio of 4.4 between the best and the worst valve. While the different clinical conditions did not modify respiratory patterns and gas exchanges, a significant effect on the Borg scale rating was observed using ANOVA and post hoc analysis of baseline versus worst valve and one of the best valves versus worst valve. In conclusion, the variety of aerodynamic characteristics of phonation valves should be considered when choosing the device, according to the underlying condition of the patients benefiting from their use.

Chronic granulomatous disease and peripheral ulcerative keratitis: a rare case of recurrent external ocular disease.

CLINICAL REPORT: We report a case of a 29-year-old lady, with known Chronic Granulomatous Disease, who presented with an acneiform scarring facial and trunk eruption and sore red eyes. Slitlamp examination showed limbal granulomas and adjacent peripheral ulcerative keratitis. DISCUSSION: The authors are considering the possible causes of the keratitis. As there were no signs of blepharitis at the time of initial presentation, the keratitis was most likely mediated by the adjacent limbal granuloma, and not due to Staphylococcal hypersensitivity. CONCLUSION: Although ocular involvement in CGD has been described before, this is the first article that describes limbal granulomata and peripheral ulcerative keratitis. Multidisciplinary management with longstanding oral antibiotic treatment, and topical combined antibiotic-steroid treatment were required to bring the condition under control.

Snoring detection during auto-nasal continuous positive airway pressure.

A bench study using an artificial lung model was performed to evaluate the snoring detection sensitivity of six (commercially available) auto-nasal continuous positive airway pressure (NCPAP) devices. Snoring was simulated by a loudspeaker connected to the lung model and abruptly activated during 1 s of each inspiratory period to induce pressure oscillation. The oscillation frequencies chosen were 30, 60, 90, and 120 Hz. For each frequency, the amplitude of the pressure oscillation produced by the loudspeaker was adjusted to find the threshold at which the auto-nCPAP devices detected snoring. Differences in pressure-amplitude thresholds of up to three-fold were found across auto-nCPAP devices. A randomized clinical study to compare the effects of the least sensitive (Virtuoso LX; Respironics, Nantes, France) and one of the most sensitive, (Goodknight 418A; Malinckrodt, Nancy, France) devices, in two groups of six patients with obstructive sleep apnoea syndrome was then conducted. Goodknight 418A was more sensitive than Virtuoso LX for detecting snoring (mean +/- SD 92 +/- 11% versus 50 +/- 39% respectively, p = 0.03). To conclude, striking differences exist between auto-nasal continuous positive airway pressure devices in sensitivity for detecting snoring.

Pneumatosis coli and multi-slice helical CT virtual colonoscopy.

Helical CT colography is improved by multislicing due to thinner slices. The case reported shows the potential of multislice HCT colography to demonstrate gas-filled cysts on axial images as well as on CT endoscopy, and consequently the extent of the disease exceeding the sigmoid, as was diagnosed by conventional coloscopy.

Inaccuracy of tidal volume delivered by home mechanical ventilators.

Ideally, the inspired (tidal) volume (V(T)) provided by a volume-controlled ventilation device should not change when the pressure imposed on the ventilator varies. A bench study evaluation of V(T) versus pressure was performed on 10 commercially available devices. The difference between the desired V(T) and the observed V(T) reached 100 mL for some devices when inspiratory resistance was at its lowest, rising to 150 mL when inspiratory resistance was increased to obtain peak airway pressure of 60 cmH2O. The present data indicate that some home ventilators are inaccurate in delivering the preset tidal volume when the pressure imposed on the ventilator is increased to simulate high airway resistance.