Modelling mass drug administration strategies for reducing scabies burden in Monrovia, Liberia

Scabies is a parasitic infestation with high global burden. Mass drug administrations (MDAs) are recommended for communities with a scabies prevalence of >10%. Quantitative analyses are needed to demonstrate the likely effectiveness of MDA recommendations. In this study, we developed an agent-based model of scabies transmission calibrated to demographic and epidemiological data from Monrovia. We used this model to compare the effectiveness of MDA scenarios for achieving scabies elimination and reducing scabies burden, as measured by time until recrudescence following delivery of an MDA and disability-adjusted-life-years (DALYs) averted. Our model showed that three rounds of MDA delivered at six-month intervals and reaching 80% of the population could reduce prevalence below 2% for three years following the final round, before recrudescence. When MDAs were followed by increased treatment uptake, prevalence was maintained below 2% indefinitely. Increasing the number of and coverage of MDA rounds increased the probability of achieving elimination and the number of DALYs averted. Our results suggest that acute reduction of scabies prevalence by MDA can support a transition to improved treatment access. This study demonstrates how modelling can be used to estimate the expected impact of MDAs by projecting future epidemiological dynamics and health gains under alternative scenarios.

Effectiveness of community-based burden estimation to achieve elimination of lymphatic filariasis: A comparative cross-sectional investigation in Côte d'Ivoire

For lymphatic filariasis (LF) elimination, endemic countries must document the burden of LF morbidity (LFM). Community-based screening (CBS) is used to collect morbidity data, but evidence demonstrating its reliability is limited. Recent pilots of CBS for LFM alongside mass drug administration (MDA) in Côte d'Ivoire suggested low LFM prevalence (2.1-2.2 per 10,000). We estimated LFM prevalence in Bongouanou District, Côte d'Ivoire, using a comparative cross-sectional design. We compared CBS implemented independently of MDA, adapted from existing Ministry of Health protocols, to a population-based prevalence survey led by formally trained nurses. We evaluated the reliability of case identification, coverage, equity, and cost of CBS. CBS identified 87.4 cases of LFM per 10,000; the survey identified 47.5 (39.4-56.3; prevalence ratio [PR] 1.84; 95% CI 1.64-2.07). CBS identified 39.7 cases of suspect lymphoedema per 10,000; the survey confirmed 35.1 (29.2-41.5) filarial lymphoedema cases per 10,000 (PR 1.13 [0.98-1.31]). CBS identified 96.5 scrotal swellings per 10,000; the survey found 91.3 (83.2-99.8; PR 1.06 [0.93-1.21]); including 33.9 (27.7-38.8) filarial hydrocoele per 10,000 (PR of suspect to confirmed hydrocele 2.93 [2.46-3.55]). Positive predictive values for case identification through CBS were 65.0% (55.8-73.5%) for filarial lymphoedema; 93.7% (89.3-96.7%) for scrotal swellings; and 34.0% (27.3-41.2%) for filarial hydrocoele. Households of lower socioeconomic status and certain minority languages were at risk of exclusion. Direct financial costs were $0.17 per individual targeted and $69.62 per case confirmed. Our community-based approach to LFM burden estimation appears scalable and provided reliable prevalence estimates for LFM, scrotal swellings and LF-lymphoedema. The results represent a step-change improvement on CBS integrated with MDA, whilst remaining at programmatically feasible costs. Filarial hydrocoele cases were overestimated, attributable to the use of case definitions suitable for mass-screening by informal staff. Our findings are broadly applicable to countries aiming for LF elimination using CBS. The abstract is available in French in the S1 File.

Longitudinal antibody and T cell responses in Ebola virus disease survivors and contacts: an observational cohort study

BACKGROUND

The 2013-16 Ebola virus disease epidemic in west Africa caused international alarm due to its rapid and extensive spread resulting in a significant death toll and social unrest within the affected region. The large number of cases provided an opportunity to study the long-term kinetics of Zaire ebolavirus-specific immune response of survivors in addition to known contacts of those infected with the virus.

METHODS

In this observational cohort study, we worked with leaders of Ebola virus disease survivor associations in two regions of Guinea, Guéckédou and Coyah, to recruit survivors of Ebola virus disease, contacts from households of individuals known to have had Ebola virus disease, and individuals who were not knowingly associated with infected individuals or had not had Ebola virus disease symptoms to serve as negative controls. We did Zaire ebolavirus glycoprotein-specific T cell analysis on peripheral blood mononuclear cells (PBMCs) on location in Guinea and transported plasma and PBMCs back to Europe for antibody quantification by ELISA, functional neutralising antibody analysis using live Zaire ebolavirus, and T cell phenotype studies. We report on the longitudinal cellular and humoral response among Ebola virus disease survivors and highlight potentially paucisymptomatic infection.

FINDINGS

We recruited 117 survivors of Ebola virus disease, 66 contacts, and 23 negative controls. The mean neutralising antibody titre among the Ebola virus disease survivors 3-14 months after infection was 1/174 (95% CI 1/136-1/223). Individual results varied greatly from 1/10 to more than 1/1000 but were on average ten times greater than that induced after 1 month by single dose Ebola virus vaccines. Following reactivation with glycoprotein peptide, the mean T cell responses among 116 Ebola virus disease survivors as measured by ELISpot was 305 spot-forming units (95% CI 257-353). The dominant CD8+ polyfunctional T cell phenotype, as measured among 53 Ebola virus disease survivors, was interferon γ+, tumour necrosis factor+, interleukin-2-, and the mean response was 0·046% of total CD8+ T cells (95% CI 0·021-0·071). Additionally, both neutralising antibody and T cell responses were detected in six (9%) of 66 Ebola virus disease contacts. We also noted that four (3%) of 117 individuals with Ebola virus disease infections did not have circulating Ebola virus-specific antibodies 3 months after infection.

INTERPRETATION

The continuous high titre of neutralising antibodies and increased T cell response might support the concept of long-term protective immunity in survivors. The existence of antibody and T cell responses in contacts of individuals with Ebola virus disease adds further evidence to the existence of sub-clinical Ebola virus infection.

FUNDING

US Food & Drug Administration, Horizon 2020 EU EVIDENT, Wellcome, UK Department for International Development.

TRANSLATION

For the French translation of the abstract see Supplementary Materials section.

Mapping suitability for Buruli ulcer at fine spatial scales across Africa: A modelling study

Buruli ulcer (BU) is a disabling and stigmatising neglected tropical disease (NTD). Its distribution and burden are unknown because of underdiagnosis and underreporting. It is caused by Mycobacterium ulcerans, an environmental pathogen whose environmental niche and transmission routes are not fully understood. The main control strategy is active surveillance to promote early treatment and thus limit morbidity, but these activities are mostly restricted to well-known endemic areas. A better understanding of environmental suitability for the bacterium and disease could inform targeted surveillance, and advance understanding of the ecology and burden of BU. We used previously compiled point-level datasets of BU and M. ulcerans occurrence, evidence for BU occurrence within national and sub-national areas, and a suite of relevant environmental covariates in a distribution modelling framework. We fitted relationships between BU and M. ulcerans occurrence and environmental predictors by applying regression and machine learning based algorithms, combined in an ensemble model to characterise the optimal ecological niche for the disease and bacterium across Africa at a resolution of 5km x 5km. Proximity to waterbodies was the strongest predictor of suitability for BU, followed potential evapotranspiration. The strongest predictors of suitability for M. ulcerans were deforestation and potential evapotranspiration. We identified patchy foci of suitability throughout West and Central Africa, including areas with no previous evidence of the disease. Predicted suitability for M. ulcerans was wider but overlapping with that of BU. The estimated population living in areas predicted suitable for the bacterium and disease was 46.1 million. These maps could be used to inform burden estimations and case searches which would generate a more complete understanding of the spatial distribution of BU in Africa, and may guide control programmes to identify cases beyond the well-known endemic areas.

A community-based validation of the International Alliance for the Control of Scabies Consensus Criteria by expert and non-expert examiners in Liberia

Background

The International Alliance for the Control of Scabies (IACS) recently published expert consensus criteria for scabies diagnosis. Formal validation of these criteria is needed to guide implementation. We conducted a study to provide detailed description of the morphology and distribution of scabies lesions as assessed by dermatologists and validate the IACS criteria for diagnosis by both expert and non-expert examiners.

Methods

Participants from a community in Monrovia, Liberia, were independently assessed by two dermatologists and six non-expert examiners. Lesion morphology and distribution were documented based on the dermatologist examination. Diagnoses were classified by IACS criteria and the sensitivity and specificity of non-expert examiner assessments calculated.

Results

Papules were the most common lesions (97.8%). Burrows were found in just under half (46.7%) and dermatoscopy was positive in a minority (13.3%). Scabies lesions were found in all body regions but more than 90% of patients could have been diagnosed by an examination of only the limbs. Severity of itch was associated with lesion number (p = 0.003). The sensitivity of non-expert examiners to detect typical scabies ranged between 69–83% and specificity 70–96%. The sensitivity of non-expert examiners was higher in more extensive disease (78–94%).

Conclusions

The IACS criteria proved a valid tool for scabies diagnosis. For the purposes of implementation papules and burrows represent truly ‘typical’ scabies lesions.

Non-expert examiners are able to diagnose scabies with a high degree of accuracy, demonstrating they could form a key component in population-level control strategies.

Scabies is a very common skin condition in both high- and low-income settings with hundreds of millions of people affected each year. Recently standardised criteria have been proposed to help improve the quality of scabies diagnosis, in particular in low income settings where the access to a skin specialist is very limited.

In this study, conducted in Liberia, expert examiners conducted a thorough examination and recorded what different types of skin problems they found in participants with and without scabies. We then compared the accuracy of a diagnosis of scabies made by dermatologists to that made by non-specialist healthcare workers who had received a short training course over three days.

We found that papules were the most common type of scabies lesion and were found in almost every single patient with scabies. A second type of skin lesion called a burrow was the next most common and was found in just under half of the participants. Other types of scabies lesions which have been described were rare in this study. We found that after the short training course the non-specialists were able to detect the majority of the cases of scabies correctly.

Our study has helped provide detailed data on exactly what types of skin changes are typical of scabies and demonstrated how short training programmes can help improve the skill of non-specialist examiners in diagnosing scabies.

MRI versus CT: a retrospective investigation of the feasibility and agreeability in post-operative evaluation of screw position after posterior lumbar interbody fusion

PURPOSE

Many patients receive magnetic resonance (MR) and computed tomography (CT) scans post-operatively to review screw placement. Traditionally, CT is diagnostic but as metal artefact reduction sequences are advancing in MR, the necessity for both MR and CT scans is questionable. The objective is to establish the statistical agreeability of MR and CT for evaluation of adequate screw placement in posterior lumbar interbody fusion.

METHODS

This opportunistic retrospective study of 58 patients investigated 297 images of 296 implanted screws. Post-operative MR and CT images were scrutinised for depiction of lumbar pedicle screw position using a 5-point scale. Kappa value for statistical agreeability tested MR against CT.

RESULTS

The 297 images of screws resulted in strong to near-perfect agreement between MR and CT (n = 297 k = 0.8042 p < 0.025). MRI resulted in high sensitivity (88.7%) and positive predictive value (78.3%). MRI demonstrated very high specificity (96.2%) and negative predictive value (98.2%). MR depicted screws (mean 12.6 mm diameter, mean 65.3 mm length) with 50% error in diameter and 30% in length from susceptibility artefact compared to manufacturer dimensions (6.5-7.5 mm diameter, 40-50 mm length). Adequate screw placement was high despite this (85.8%). On MR, the cortex border visibility was 60.7% and the spinal canal visibility was 74.6%.

CONCLUSION

There is strong to near-perfect agreement between MR and CT for evaluating adequate screw position in PLIF surgery. MR alone is useful for analyzing screw placement and should be considered first-line imaging in uncomplicated cases with CT analysis reserved for cases of uncertainty.

LEVEL OF EVIDENCE

Level III retrospective cohort study.

"Buruli ulcer and leprosy, they are intertwined": Patient experiences of integrated case management of skin neglected tropical diseases in Liberia

BACKGROUND

Skin neglected tropical diseases (NTDs) such as Buruli ulcer (BU) and leprosy produce significant stigma and disability. Shared clinical presentations and needs for care present opportunities for integrated case management in co-endemic areas. As global policies are translated into local integrated services, there remains a need to monitor what new configurations of care emerge and how individuals experience them.

METHODS

To explore patient experiences of integrated case management for skin NTDs, in 2018, we conducted a field-based qualitative case series in a leprosy rehabilitation centre in Ganta, Liberia where BU services were recently introduced. Twenty patients with BU (n = 10) and leprosy (n = 10) participated in in-depth interviews that incorporated photography methods. We contextualised our findings with field observations and unstructured interviews with health workers.

FINDINGS

The integration of care for BU and leprosy prompted new conceptualisations of these diseases and experiences of NTD stigma. Some patients felt anxiety about using services because they feared being infected with the other disease. Other patients viewed the two diseases as 'intertwined': related manifestations of the same condition. Configurations of inter-disease stigma due to fear of transmission were buffered by joint health education sessions which also appeared to facilitate social support between patients in the facility. For both diseases, medication and wound care were viewed as the cornerstones of care and appreciated as interventions that led to rehabilitation of the whole patient group through shared experiences of healing, avoidance of physical deformities and stigma reduction. Patient accounts of intense pain during wound care for BU and inability of staff to manage severe complications, however, exposed some shortcomings of medical care for the newly integrated service, as did patient fears of long-lasting disability due to lack of physiotherapy services.

SIGNIFICANCE

Under integrated care policies, the possibility of new discourses about skin NTD identities emerging along with new configurations of stigma may have unanticipated consequences for patients' experiences of case management. The social experience of integrated medication and wound dressing has the potential to link patients within a single, supportive patient community. Control programmes with resource constraints should anticipate potential challenges of integrating care, including the need to ameliorate lasting disability and provide adequate clinical management of severe BU cases.

P76 Skip laminectomy versus cervical laminectomy, an analysis of patient reported outcomes, spinal alignment and re-operation rates: the leeds spinal unit experience (2008–2016)

Objectives

To compare clinical, radiological and complication results between skip laminectomy and cervical laminectomy for posterior cervical decompression for cervical spondylotic myelopathy.

Design

Retrospective single institution cohort study.

Subjects

Subjects underwent primary skip or cervical laminectomy between 2008–2016.

Methods

Statistical analysis compared pre- and post-operative differences in Visual Analogue Scale, Neck Disability Index and radiological differences in sagittal alignment of the vertebral bodies. Analysis of re-operation rates was performed.

Results

A total of 42 and 29 patients had skip and cervical laminectomy respectively. Median follow up was 32±23.1 (Range: 1–325) weeks. Post-operatively there was no difference in patient reported outcomes namely Visual Analogue Scale and Neck Disability Index between skip laminectomy and cervical laminectomy groups compared to pre-operatively (p=0.64, p=0.75). No difference was seen in sagittal alignment between both groups following surgery (p=0.65). Three patients (7.1%) in the skip laminectomy group and two patients (6.9%) in the cervical laminectomy group required revision surgery to the cervical spinal region at a different level to the original surgery. No patients needed further instrumentation.

Conclusions

Both skip laminectomy and cervical laminectomy appear to deliver similar outcomes with regards to patient reported outcomes, preserving sagittal alignment and re-operation rates over this short follow-up period.

Use of an Ultrasonic Bone Curet for the Extraction of a Cervical Artificial Disc: A Novel Application: A Case Report

CASE

Eighteen months after implantation of a C6-C7 cervical artificial disc (ProDisc-C; DePuy Synthes), a 44-year-old woman presented with right-sided C7 radiculopathy. Imaging revealed posterior subsidence of the prosthesis, with C7 foraminal stenosis. An ultrasonic curet was used to safely and effectively extract the prosthesis without neurologic complication; safe access for the insertion of an intervertebral cage was facilitated.

CONCLUSION

The ultrasonic curet was a safe and effective adjunct for revision artificial cervical disc replacement surgery; this technique may help to reduce potential injury to neural structures in a procedure with a traditionally high complication rate.

Partial anterior sacrectomy with nerve preservation to treat locally advanced rectal cancer

AIM

Most studies that have reported outcomes after composite abdomino-sacral resection for locally advanced/recurrent rectal cancer have involved resections below the S2/3 disc space. Involvement of the sacrum above this level is uncommon and, until recently, was considered a contraindication to resection.

METHOD

We report here a surgical technique to deal with high sacral involvement with an anterior approach and maintenance of sacropelvic stability.

RESULTS

The operative findings confirmed a locally perforated rectal cancer with an associated abscess cavity and direct invasion into S2. Given the likelihood that a complete dislocation of the sacrum would cause significant neurological damage and pelvic instability without oncological benefit, we opted for a partial high anterior sacrectomy with nerve preservation. The patient made an uncomplicated recovery without neurological deficit and was able to walk with the aid of crutches from postoperative day 3.

CONCLUSION

While a high sacral transection is appropriate for some patients with locally advanced/recurrent rectal cancer, operative decisions and options should be tailored to each individual.

Cervical arthroplasty: the beginning, the middle, the end?

Cervical arthroplasty has developed as an alternative to spinal fusion for the treatment of cervical radiculopathy and myelopathy. The popularity of artificial discs has grown as the evidence of complications following arthrodesis has increased, making the theoretical advantages (motion preservation, altering the natural history of disease, prevention of adjacent segment disease) of disc replacement more attractive. However, as more discs are implanted and the length of follow-up increases, reported complications such as heterotopic ossification, device migration and spontaneous fusion of arthroplasty devices are growing. As a result, surgeons and patients face a challenge when deciding between motion-preserving or fusion surgery. Currently, there is inadequate evidence to promote extensive use of artificial discs for cervical spondylosis, despite promising short-term and intermediate clinical outcomes. However, there is also insufficient evidence to cease using them completely. The use of arthroplasty over fusion in the long term can only be justified if the incidence of adjacent segment disease decreases as a result. Despite the level of investment and research into arthroplasty outcomes, long-term follow-up has yet to be completed and has not convincingly demonstrated the effect of artificial discs on adjacent segment disease. Further long-term randomised trials are necessary to determine whether cervical arthroplasty is able to reduce the incidence of adjacent segment disease and, in doing so, replace arthrodesis as the gold standard treatment for cervical spondylosis.

The use of titanium non-penetrating clips to close the spinal dura

We present the results of our initial experience in the use of non-penetrating titanium clips in the closure of spinal dura. A retrospective analysis of case notes of patients identified from the unit database was carried out, limited to adults. A proforma that included demographic details, the diagnosis, the procedure undertaken, whether or not additional dural closure methods were used, the use of bed rest and any complications, including cerebrospinal fluid (CSF) leak. There were 58 patients with a mean age of 53 years. The commonest diagnoses were meningioma, ependymoma and neurofibroma. Eight patients had additional methods of dural closure used and approximately half the patients had a period of postoperative bed rest. Eight patients (13.7%) had a CSF leak. Our early experience with the use of non-penetrating clips for the closure of the spinal dura is presented. We have found them easy to use, especially in anatomically-restricted spaces and rapid in their application. However, our results have revealed an unexpectedly high complication rate. A further prospective study to evaluate them more fully is planned.

Neurogenic fever

Fever in patients with severe head injury is a commonly-encountered diagnostic and management problem. Neurogenic fever (NF) is a non-infectious source of fever in the patient with head injury and, if untreated, can cause damage to the brain in many ways. Until recently, NF was thought to be a relatively rare consequence of traumatic brain injury (TBI), but other studies have reported that four to 37 percent of TBI survivors experience this sequela. Patients with TBI are immunocompromised to a certain extent and this predisposes them to sepsis, which should be a primary concern particularly in comatose patients. NF is essentially a diagnosis of exclusion. It is only when sepsis is excluded, can we consider NF. Though in the acute phase of severe TBI, brain temperature is indeed higher than the core temperature, but that significance is uncertain with regard to outcome prediction, since there has been a paucity of work on the use of direct methods of brain temperature monitoring. In summary, the pathophysiology and management of NF is not well understood and needs more research and understanding for better management and a favourable outcome.

Cervical spine metastasis from adrenal pheochromocytoma

Metastatic tumours are the most common type of tumours in the spine of which only 10% occur in the cervical spine. We report a rare presentation of metastatic pheochromocytoma of the cervical spine which was successfully treated operatively. Adequate precautions should be taken during surgery as the tumour is very vascular. Radiotherapy is useful in the treatment of residual tumour.

Acute neurologic deterioration following lumbar puncture in an epidural abscess occurring 14 months after epidural catheter placement

We report the case of a 19-year-old girl admitted to the hospital with a 2-month history of back pain and a 1-week history of severe weakness, who underwent a diagnostic lumbar puncture which was swiftly followed by acute neurologic deterioration requiring ventilation. She was subsequently shown to have an epidural abscess extending from the second cervical to the fifth lumbar vertebrae. She had received uneventful epidural analgesia for childbirth 14 months previously. The case is unusual in both the acute deterioration following lumbar puncture, and also in the length of time from epidural siting to abscess formation, if this were indeed the source of the infection.

Ruptured spinal arteriovenous malformation causing cauda equina syndrome: case report

We describe the case of an acute cauda equina syndrome secondary to a confined subarachnoid bleed from a spinal arteriovenous malformation. The patient was elderly and made a complete neurological recovery following surgery.

Sub-galeal coiling of the proximal and distal components of a ventriculo-peritoneal shunt. An unusual complication and proposed mechanism

We describe the case of a child in whom proximal migration of the peritoneal catheter and extrusion of the ventricular catheter resulted in the entire ventriculo-peritoneal shunt along with the shunt chamber (Orbis Sigma II valve) lying in a sub-galeal pocket in the occipital region in a tightly coiled fashion. This coiling was very similar in appearance to that of the pre-insertion shunt in the packaging when it is supplied; hence it is postulated that the migration was secondary to retained 'memory' of the shunt tubing. This is a rare complication of ventriculo-peritoneal shunt, which has not been described before.

Minimalist placement of external ventricular drains. A quick, safe, cheap and cosmetic procedure

We report the use of a twist drill method for placement of external ventricular drains and ventriculoperitoneal shunts. We have found this method to be efficient and safe, and provides an excellent cosmetic effect.

Meningioma recurrence at a different site masquerading as a subdural hematoma. Case report

It is unusual for a meningioma to recur at a distant site. It is more unusual for a meningioma to present as a subdural hematoma. The authors report a unique case in which both of these events occurred in the same patient during a 4-year period. The authors discuss the pathogenesis of these rare events with regard to meningiomas.

Raised plasma polyamine concentrations in patients with severe head injury

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Medullary cell carcinoma of the thyroid: metastases to the central nervous system

We document a case of a patient who had been treated for a medullary cell carcinoma of the thyroid three years previously and who presented with a three month history of ataxia, weakness and headache. A CT scan showed contrast enhancing lesions in the posterior fossa. An MIBG uptake scan showed that there was some uptake in the cerebellar lesions; however, it was not sufficient to rely on this alone for treatment. The larger of these lesions was therefore surgically resected. Immunocytochemistry, using CAM 5.2, CEA and chromogranin, demonstrated a positive reaction which strongly favoured a diagnosis of metastases from a medullary cell carcinoma of the thyroid. However, absolute confirmation of the diagnosis was obtained using immunocytochemistry with calcitonin. Medullary cell carcinomas of the thyroid usually spread locally and metastasis to the brain has never before been reported.

Perils of a 'true' posterior communicating artery aneurysm

Successful 'clipping' of the apparent neck of a posterior communicating artery aneurysm was carried out, but 2 days later the patient had a further haemorrhage and died. Postmortem examination revealed that the aneurysm was that of a rare fusiform 'true' posterior communicating artery aneurysm.

Unusual presentation of a germ cell neoplasm

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