A case-control study of factors associated with SARS-CoV-2 infection among healthcare workers in Colombia.

BACKGROUND: Healthcare Workers (HCW) are repeatedly exposed to SARS-CoV-2 infection. The aim of this study was to identify factors associated with SARS-CoV-2 infection among HCW in one of the largest cities in Colombia. METHODS: We conducted a case-control study, where cases had a positive reverse transcription-polymerase chain reaction and controls had a negative result. Participants were randomly selected and interviewed by phone. Analyses were performed using logistic regression models. RESULTS: A total of 110 cases and 113 controls were included. Men (AdjOR 4.13 95% CI 1.70-10.05), Nurses (AdjOR 11.24 95% CI 1.05-119.63), not using a high-performance filtering mask (AdjOR 2.27 95% CI 1.02-5.05) and inadequate use of personal protective equipment (AdjOR 4.82 95% CI 1.18-19.65) were identified as risk factors. Conversely, graduate (AdjOR 0.06 95% CI 0.01-0.53) and postgraduate (AdjOR 0.05 95% CI 0.005-0.7) education, feeling scared or nervous (AdjOR 0.45 95% CI 0.22-0.91), not always wearing any gloves, caps and goggles/face shields (AdjOR 0.10 95% CI 0.02-0.41), and the use of high-performance filtering or a combination of fabric plus surgical mask (AdjOR 0.27 95% CI 0.09-0.80) outside the workplace were protective factors. CONCLUSION: This study highlights the protection provided by high-performance filtering masks or double masking among HCW. Modifiable and non-modifiable factors and the difficulty of wearing other protective equipment needs to be considered in designing, implementing and monitoring COVID-19 biosafety protocols for HCW.

Guillain-Barré Syndrome Associated with Zika Virus Infection in Colombia.

BACKGROUND: Zika virus (ZIKV) infection has been linked to the Guillain-Barré syndrome. From November 2015 through March 2016, clusters of cases of the Guillain-Barré syndrome were observed during the outbreak of ZIKV infection in Colombia. We characterized the clinical features of cases of Guillain-Barré syndrome in the context of this ZIKV infection outbreak and investigated their relationship with ZIKV infection. METHODS: A total of 68 patients with the Guillain-Barré syndrome at six Colombian hospitals were evaluated clinically, and virologic studies were completed for 42 of the patients. We performed reverse-transcriptase-polymerase-chain-reaction (RT-PCR) assays for ZIKV in blood, cerebrospinal fluid, and urine, as well as antiflavivirus antibody assays. RESULTS: A total of 66 patients (97%) had symptoms compatible with ZIKV infection before the onset of the Guillain-Barré syndrome. The median period between the onset of symptoms of ZIKV infection and symptoms of the Guillain-Barré syndrome was 7 days (interquartile range, 3 to 10). Among the 68 patients with the Guillain-Barré syndrome, 50% were found to have bilateral facial paralysis on examination. Among 46 patients in whom nerve-conduction studies and electromyography were performed, the results in 36 patients (78%) were consistent with the acute inflammatory demyelinating polyneuropathy subtype of the Guillain-Barré syndrome. Among the 42 patients who had samples tested for ZIKV by RT-PCR, the results were positive in 17 patients (40%). Most of the positive RT-PCR results were in urine samples (in 16 of the 17 patients with positive RT-PCR results), although 3 samples of cerebrospinal fluid were also positive. In 18 of 42 patients (43%) with the Guillain-Barré syndrome who underwent laboratory testing, the presence of ZIKV infection was supported by clinical and immunologic findings. In 20 of these 42 patients (48%), the Guillain-Barré syndrome had a parainfectious onset. All patients tested were negative for dengue virus infection as assessed by RT-PCR. CONCLUSIONS: The evidence of ZIKV infection documented by RT-PCR among patients with the Guillain-Barré syndrome during the outbreak of ZIKV infection in Colombia lends support to the role of the infection in the development of the Guillain-Barré syndrome. (Funded by the Bart McLean Fund for Neuroimmunology Research and others.).

Association of metabolic syndrome and chronic periodontitis in Colombians.

BACKGROUND: Metabolic syndrome (MetS) is a common chronic condition that increases the cardiovascular disease risk and is also linked to periodontitis. The study aim was to determine if a relationship exists between MetS and chronic periodontitis in adult Colombians. METHODS: Participants were 220 healthy-gingivitis subjects and 431 periodontitis patients coming from the three largest Colombian cities. Periodontal status and MetS were determined in subjects. Univariate analysis and odds ratio were calculated within the 95 % confidence intervals and chi2 test compared the groups. Variables were compared among the clinical periodontal groups and MetS by Wilcoxon and multivariate analysis, and logistic regression was performed for MetS and periodontitis. RESULTS: MetS had higher prevalence in periodontitis group (6.3 %) versus controls (3.2 %). In multivariate analysis, periodontitis was associated with MetS (adjusted OR = 2.72, 95 % CI 1.09-6.79), glucose intolerance with another component of MetS (adjusted OR = 1.78, 1.16 to 2.72), glucose resistance (adjusted OR = 11.46, 95 % CI 1.41-92.88), smoking (OR = 1.72, 95 % CI 1.09-2.71), and city of origin (2.69, 95 % CI 1.79-4.04). CONCLUSION: The study confirmed the positive association between MetS and periodontitis, being glucose sensitivity the strongly associated component. CLINICAL RELEVANCE: MetS must be taken into account by the dentist when evaluating risk factors for periodontitis, being useful for dentists to evaluate glycemia, lipidic profile, central obesity, and high blood pressure in patients. Interdisciplinary treatment must be recommended when a patient with MetS and periodontitis is being treated.

Estimation of the Antirelapse Efficacy of Tafenoquine, Using Plasmodium vivax Genotyping.

UNLABELLED: Prevention of relapse of Plasmodium vivax infection is a key treatment goal in malaria. Use of P. vivax genotyping in a multicenter, double-blind, randomized, placebo-controlled phase 2b study in Peru, India, Thailand, and Brazil allowed determination of genetically heterologous or homologous P. vivax infection recurrence following receipt of chloroquine plus one of 4 doses of tafenoquine (50, 100, 300, or 600 mg) or chloroquine plus primaquine, compared with receipt of chloroquine alone. The antihypnozoite efficacy of tafenoquine was evident as a reduction in homologous recurrences of P. vivax infection as drug doses were increased. No clear dose-response pattern was evident for heterologous recurrences of P. vivax infection. Rates of homologous recurrence of P. vivax infection appear to be clinically useful for comparing drug efficacy for the prevention of P. vivax infection relapse. CLINICAL TRIALS REGISTRATION: NCT01376167.

Influence of breastfeeding and postnatal nutrition on cardiovascular remodeling induced by fetal growth restriction.

BACKGROUND: Our aim was to determine the influence of breastfeeding and postnatal nutrition on cardiovascular remodeling induced by fetal growth restriction (FGR). METHODS: A cohort study including 81 children with birthweight <10th centile (FGR) and 121 with adequate fetal growth for gestational age (AGA) was conducted. Cardiovascular endpoints were left ventricular sphericity index (LVSI), carotid intima-media thickness (cIMT), and blood pressure (BP) at 4-5 y of age. The combined effect of FGR and postnatal variables-including breastfeeding, fat dietary intake, and BMI-on cardiovascular endpoints was assessed by linear and robust regressions. RESULTS: FGR was the strongest predictor of cardiovascular remodeling in childhood, leading to lower LVSI and increased cIMT and BP as compared with AGA. Breastfeeding >6 mo (coefficient: 0.0982) and healthy-fat dietary intake (coefficient: -0.0128) showed an independent beneficial effect on LVSI and cIMT, respectively. Overweight/obesity induced an additional increment of 1 SD on cIMT in FGR children (interaction coefficient: 0.0307) when compared with its effect in AGA. BMI increased systolic BP (coefficient: 0.7830) while weight catch-up increased diastolic BP (coefficient: 4.8929). CONCLUSIONS: Postnatal nutrition ameliorates cardiovascular remodeling induced by FGR. Breastfeeding and healthy-fat dietary intake improved while increased BMI worsened cardiovascular endpoints, which opens opportunities for targeted postnatal interventions from early life.

Geographic distribution of amino acid mutations in DHFR and DHPS in Plasmodium vivax isolates from Lao PDR, India and Colombia.

BACKGROUND: Non-synonymous mutations in dhfr and dhps genes in Plasmodium vivax are associated with sulfadoxine-pyrimethamine (SP) resistance. The present study aimed to assess the prevalence of point mutations in P. vivax dhfr (pvdhfr) and P. vivax dhps (pvdhps) genes in three countries: Lao PDR, India and Colombia. METHODS: Samples from 203 microscopically diagnosed vivax malaria were collected from the three countries. Five codons at positions 13, 57, 58, 61, and 117 of pvdhfr and two codons at positions 383 and 553 of pvdhps were examined by polymerase chain reaction-restriction fragment length polymorphism methodology. RESULTS: The largest number of 58R/117 N double mutations in pvdhfr was observed in Colombia (94.3 %), while the corresponding wild-type amino acids were found at high frequencies in Lao PDR during 2001-2004 (57.8 %). Size polymorphism analysis of the tandem repeats within pvdhfr revealed that 74.3 % of all the isolates carried the type B variant. Eighty-nine per cent of all the isolates examined carried wild-type pvdhps A383 and A553. CONCLUSIONS: Although SP is not generally used to treat P. vivax infections, mutations in dhfr and dhps that confer antifolate resistance in P. vivax are common. The data strongly suggest that, when used primarily to treat falciparum malaria, SP can exert a substantial selective pressure on P. vivax populations, and this can lead to point mutations in dhfr and dhps. Accurate data on the global geographic distribution of dhfr and dhps genotypes should help to inform anti-malarial drug-use policies.

The use of rapid dengue diagnostic tests in a routine clinical setting in a dengue-endemic area of Colombia.

There is insufficient evidence of the usefulness of dengue diagnostic tests under routine conditions. We sought to analyse how physicians are using dengue diagnostics to inform research and development. Subjects attending 14 health institutions in an endemic area of Colombia with either a clinical diagnosis of dengue or for whom a dengue test was ordered were included in the study. Patterns of test-use are described herein. Factors associated with the ordering of dengue diagnostic tests were identified using contingency tables, nonparametric tests and logistic regression. A total of 778 subjects were diagnosed with dengue by the treating physician, of whom 386 (49.5%) were tested for dengue. Another 491 dengue tests were ordered in subjects whose primary diagnosis was not dengue. Severe dengue classification [odds ratio (OR) 2.2; 95% confidence interval (CI) 1.1-4.5], emergency consultation (OR 1.9; 95% CI 1.4-2.5) and month of the year (OR 3.1; 95% CI 1.7-5.5) were independently associated with ordering of dengue tests. Dengue tests were used both to rule in and rule out diagnosis. The latter use is not justified by the sensitivity of current rapid dengue diagnostic tests. Ordering of dengue tests appear to depend on a combination of factors, including physician and institutional preferences, as well as other patient and epidemiological factors.

Dynamic measurements of geographical accessibility considering traffic congestion using open data: a cross-sectional assessment for haemodialysis services in Cali, Colombia.

Background: Many cities with traffic congestion lack accessibility assessments accounting for traffic congestion and equity considerations but have disaggregated georeferenced municipal-level open data on health services, populations, and travel times big data. We convened a multistakeholder intersectoral collaborative group that developed a digital, web-based platform integrating open and big data to derive dynamic spatial-temporal accessibility measurements (DSTAM) for haemodialysis services. We worked with stakeholders and data scientists and considered people's places of residence, service locations, and travel time to the service with the shortest travel time. Additionally, we predicted the impacts of strategically introducing haemodialysis services where they optimise accessibility. Methods: Cross-sectional analyses of DSTAM, accounting for traffic congestion, were conducted using a web-based platform. This platform integrated traffic analysis zones, public census and health services datasets, and Google Distance Matrix API travel-time data. Predictive and prescriptive analytics identified optimal locations for new haemodialysis services and estimated improvements. Primary outcomes included the percentage of residents within a 20-min car drive of a haemodialysis service during peak and free-flow traffic congestion. Secondary outcomes focused on optimal locations to maximise accessibility with new services and potential improvements. Findings were disaggregated by sociodemographic characteristics, providing an equity perspective. The study in Cali, Colombia, used geographic and disaggregated sociodemographic data from the adjusted 2018 Colombian census. Predicted travel times were obtained for two weeks in 2020. Findings: There were substantial traffic variations. Congestion reduced accessibility, especially among marginalised groups. For 6-12 July, free-flow and peak-traffic accessibility rates were 95.2% and 45.0%, respectively. For 23-29 November, free-flow and peak traffic accessibility rates were 89.1% and 69.7%. The locations where new services would optimise accessibility had slight variation and would notably enhance accessibility and health equity. Interpretation: Establishing haemodialysis services in targeted areas has significant potential benefits. By increasing accessibility, it would enhance urban health and equity. Funding: No external or institutional funding was received.

Health research mentorship in low-income and middle-income countries: a global qualitative evidence synthesis of data from a crowdsourcing open call and scoping review.

INTRODUCTION: Research mentorship is critical for advancing science, but there are few practical strategies for cultivating mentorship in health research resource-limited settings. WHO/TDR Global commissioned a group to develop a practical guide on research mentorship. This global qualitative evidence synthesis included data from a crowdsourcing open call and scoping review to identify and propose strategies to enhance research mentorship in low/middle-income country (LMIC) institutions. METHODS: The crowdsourcing open call used methods recommended by WHO/TDR and solicited descriptions of strategies to enhance research mentorship in LMICs. The scoping review used the Cochrane Handbook and predefined the approach in a protocol. We extracted studies focused on enhancing health research mentorship in LMICs. Textual data describing research mentorship strategies from the open call and studies from the scoping review were coded into themes. The quality of evidence supporting themes was assessed using the Confidence in the Evidence from Reviews of Qualitative research approach. RESULTS: The open call solicited 46 practical strategies and the scoping review identified 77 studies. We identified the following strategies to enhance research mentorship: recognising mentorship as an institutional responsibility that should be provided and expected from all team members (8 strategies, 15 studies; moderate confidence); leveraging existing research and training resources to enhance research mentorship (15 strategies, 49 studies; moderate confidence); digital tools to match mentors and mentees and sustain mentorship relations over time (14 strategies, 11 studies; low confidence); nurturing a culture of generosity so that people who receive mentorship then become mentors to others (7 strategies, 7 studies; low confidence); peer mentorship defined as informal and formal support from one researcher to another who is at a similar career stage (16 strategies, 12 studies; low confidence). INTERPRETATION: Research mentorship is a collective institutional responsibility, and it can be strengthened in resource-limited institutions by leveraging already existing resources. The evidence from the crowdsourcing open call and scoping review informed a WHO/TDR practical guide. There is a need for more formal research mentorship programmes in LMIC institutions.

Long term persistence of clonal malaria parasite Plasmodium falciparum lineages in the Colombian Pacific region.

BACKGROUND: Resistance to chloroquine and antifolate drugs has evolved independently in South America, suggesting that genotype - phenotype studies aimed at understanding the genetic basis of resistance to these and other drugs should be conducted in this continent. This research was conducted to better understand the population structure of Colombian Plasmodium falciparum in preparation for such studies. RESULTS: A set of 384 SNPs were genotyped in blood spot DNA samples from 447 P. falciparum infected subjects collected over a ten year period from four provinces of the Colombian Pacific coast to evaluate clonality, population structure and linkage disequilibrium (LD). Most infections (81%) contained a single predominant clone. These clustered into 136 multilocus genotypes (MLGs), with 32% of MLGs recovered from multiple (2 - 28) independent subjects. We observed extremely low genotypic richness (R = 0.42) and long persistence of MLGs through time (median = 537 days, range = 1 - 2,997 days). There was a high probability (>5%) of sampling parasites from the same MLG in different subjects within 28 days, suggesting caution is needed when using genotyping methods to assess treatment success in clinical drug trials. Panmixia was rejected as four well differentiated subpopulations (FST = 0.084 - 0.279) were identified. These occurred sympatrically but varied in frequency within the four provinces. Linkage disequilibrium (LD) decayed more rapidly (r2 = 0.17 for markers <10 kb apart) than observed previously in South American samples. CONCLUSIONS: We conclude that Colombian populations have several advantages for association studies, because multiple clone infections are uncommon and LD decays over the scale of one or a few genes. However, the extensive population structure and low genotype richness will need to be accounted for when designing and analyzing association studies.

Noninferiority of miltefosine versus meglumine antimoniate for cutaneous leishmaniasis in children.

BACKGROUND: Children have a lower response rate to antimonial drugs and higher elimination rate of antimony (Sb) than adults. Oral miltefosine has not been evaluated for pediatric cutaneous leishmaniasis. METHODS: A randomized, noninferiority clinical trial with masked evaluation was conducted at 3 locations in Colombia where Leishmania panamensis and Leishmania guyanensis predominated. One hundred sixteen children aged 2-12 years with parasitologically confirmed cutaneous leishmaniasis were randomized to directly observed treatment with meglumine antimoniate (20 mg Sb/kg/d for 20 days; intramuscular) (n = 58) or miltefosine (1.8-2.5 mg/kg/d for 28 days; by mouth) (n = 58). Primary outcome was treatment failure at or before week 26 after initiation of treatment. Miltefosine was noninferior if the proportion of treatment failures was ≤15% higher than achieved with meglumine antimoniate (1-sided test, α = .05). RESULTS: Ninety-five percent of children (111/116) completed follow-up evaluation. By intention-to-treat analysis, failure rate was 17.2% (98% confidence interval [CI], 5.7%-28.7%) for miltefosine and 31% (98% CI, 16.9%-45.2%) for meglumine antimoniate. The difference between treatment groups was 13.8%, (98% CI, -4.5% to 32%) (P = .04). Adverse events were mild for both treatments. CONCLUSIONS: Miltefosine is noninferior to meglumine antimoniate for treatment of pediatric cutaneous leishmaniasis caused by Leishmania (Viannia) species. Advantages of oral administration and low toxicity favor use of miltefosine in children. CLINICAL TRIAL REGISTRATION: NCT00487253.

Evaluation of remote radiologist-interpreted point-of-care ultrasound for suspected dengue patients in a primary health care facility in Colombia.

BACKGROUND: Early identification of plasma leakage may guide treatment decisions in dengue patients. This study evaluated the value of point-of-care ultrasound (POCUS) to detect plasma leakage and predict hospitalization or referral to a higher level of care in suspected dengue patients under routine conditions at a primary care facility in Colombia. METHODS: We conducted a cohort study between April 2019 and March 2020 in a primary care hospital in Cali, Colombia. We prospectively included and followed 178 patients who were at least 2 years old with fever of less than 10 days and clinician-suspected dengue. A trained general practitioner performed a standardized POCUS protocol. Images were quality-rated and overread by an expert radiologist, and her results and those of the general practitioner were compared using the Kappa index. Logistic regression was used to identify factors associated with plasma leakage at enrollment and explore its prognostic value regarding hospital admission or referral to a higher level of care. RESULTS: Half (49.6%) POCUS images were of suitable quality to be interpreted. The proportion of plasma leakage reported by the radiologist was 85.1% (95% CI: 78.6-90.2%) and 47.2% by the study physician (Kappa = 0.25, 95% CI: 0.15-0.35). The most frequent ultrasound findings were ascites (hepatorenal 87.2%, splenorenal 64%, or pelvic 21.8%) and gallbladder wall thickening (10.5%). Plasma leakage was higher in subjects with thrombocytopenia (aOR = 4, 95% CI: 1.3-12.1) and lower in patients 30-59 years old (aOR = 0.1, 95% CI: 0.0-0.4) than in those 18 years old or younger. POCUS evidence of plasma leakage (aOR = 8.2, 95% CI: 2.2-29.9), thrombocytopenia (aOR = 6.3, 95% CI: 2.4-16.0) and pulse pressure (aOR = 1.1, 95% CI: 1.07-1.2) were associated with hospital admission or referral to a higher level of care. CONCLUSIONS: Ultrasound is useful to detect plasma leakage in primary care and, challenges remain to guarantee high-quality images and diagnostic accuracy, for which a standardized dengue POCUS protocol and training program is needed.

Health research mentorship in low- and middle-income countries: a scoping review.

OBJECTIVE: The objective of this scoping review was to explore and synthesize the available literature on health research mentorship in low- and middle-income countries (LMICs). INTRODUCTION: Research mentorship is broadly considered a useful strategy to improve research capacities and research outputs. Existing literature and guidance on research mentorship have focused on high-income countries and assumed resource-rich environments. Despite the successful endeavors to improve health research capacity in LMICs, the strategies that work best under different circumstances are poorly understood. There is a need to map and understand the evidence on health research mentorship in the context of LMICs. INCLUSION CRITERIA: Sources that reported existing practices, barriers, and mitigation strategies related to health research mentorship in LMICs were included. METHODS: We searched for published and unpublished studies and reports written in English, Spanish, or Portuguese. The search strategy was not limited by search dates and the last search was conducted on January 28, 2022. The databases searched included MEDLINE (PubMed), Embase, Web of Science Core Collection, CINAHL (EBSCOhost), Cochrane Database of Systematic Reviews, and JBI Evidence Synthesis . We also searched for gray literature in a selection of websites and digital repositories. The JBI scoping review methodology was used. RESULTS: A total of 77 studies and reports were included in the review. The majority of the papers were from Africa (n=28). Others were from the Americas (n=7), South East Asia (n=4), East Mediterranean (n=2), and Western Pacific (n=2). The remaining studies were from LMICs that included at least 2 regional offices. Most of the mentorship projects (n=55) were initiated and funded by institutions from high-income countries. The first authors of 41 papers were primarily affiliated with LMICs. The findings were categorized under a description of research mentorship practices, barriers related to research mentorship, and suggested mitigation strategies. Deliverable-driven training using intensive hands-on mentorship and ongoing peer mentorship programs were some of the non-regular, non-institutionalized approaches used to improve research capacity for junior researchers in LMICs. None of the included papers focused on institutional components of research mentorship in LMICs. The barriers to research mentorship activities in LMICs included lack of clarity on mentorship, cultural variations, unbalanced power dynamics, socio-political influences, language barriers, lack of experienced mentors, and limited local funding. Institutionalizing research mentorship, adapting mentoring methodologies relying on local resources, and addressing and respecting diversity in mentorship programs were among the main strategies identified to effectively implement research mentorship in LMICs. CONCLUSIONS: Research mentorship initiatives and practices are limited in LMICs. Few available practices have been introduced by researchers and research institutions from high-income countries and those that have are not yet institutionalized. The identified existing practices, barriers, and facilitators on health research mentorship could help the design, implementation, and evaluation of programs to institutionalize health research mentorship in LMICs. REVIEW REGISTRATION: Open Science Framework osf.io/jqa9z/. SUPPLEMENTAL DIGITAL CONTENT: A Spanish-language version of the abstract of this review is available as supplemental digital content: http://links.lww.com/SRX/A32.

Diagnostic performance of two rapid tests for syphilis screening in people living with HIV in Cali, Colombia.

INTRODUCTION: There is insufficient evidence supporting the use of rapid diagnostic tests (RDTs) for syphilis in people living with HIV (PLWH). We evaluated the diagnostic performance of two commercially available RDTs (Bioline and Determine) in PLWH in Cali, Colombia. METHODS: A cross-sectional field validation study on consecutive adults with confirmed HIV diagnosis attending three outpatient clinics. Both RDTs were performed on capillary blood (CB), obtained by finger prick, and sera, by venipuncture. A combination of treponemal enzyme linked immunosorbent assay (ELISA) and Treponema pallidum haemagglutination assay (TPHA) on serum samples was the reference standard. Rapid plasma reagin (RPR) and clinical criteria were added to define active syphilis. Sensitivity and specificity, predictive values and likelihood ratios (LR) of RDTs were estimated with their corresponding 95% confidence interval (95% CI). Stratified analyses by sample type, patient characteristics, non-treponemal titers, operator and re-training were performed. RESULTS: 244 PLWH were enrolled, of whom 112 (46%) had positive treponemal reference tests and 26/234 (11.1%) had active syphilis. The sensitivities of Bioline on CB and sera were similar (96.4% vs 94.6%, p = 0.6). In contrast, Determine had a lower sensitivity on CB than sera (87.5% vs 99.1%, p<0.001). Sensitivities were lower in PLWH not receiving ART (Bioline 87.1% and Determine 64.5%, p<0.001) and for one of the operators (Bioline 85% and Determine 60%, p<0.001). Specificities of the RDTs were > 95% in most analyses. Predictive values were 90% or higher. For active syphilis, the RDTs showed a similar performance pattern but with decreased specificities. CONCLUSION: The studied RDTs have an excellent performance in PLWH to screen for syphilis and potentially for active syphilis, yet Determine performs better on sera than CB. Patient characteristics and potential difficulties operators may face in acquiring enough blood volume from finger pricks should be considered for the implementation and the interpretation of RDTs.

Guillain-Barré Syndrome Following Zika Virus Infection Is Associated With a Diverse Spectrum of Peripheral Nerve Reactive Antibodies.

BACKGROUND AND OBJECTIVES: Recent outbreaks of Zika virus (ZIKV) in South and Central America have highlighted significant neurologic side effects. Concurrence with the inflammatory neuropathy Guillain-Barré syndrome (GBS) is observed in 1:4,000 ZIKV cases. Whether the neurologic symptoms of ZIKV infection are immune mediated is unclear. We used rodent and human live cellular models to screen for anti-peripheral nerve reactive IgG and IgM autoantibodies in the sera of patients with ZIKV with and without GBS. METHODS: In this study, 52 patients with ZIKV-GBS were compared with 134 ZIKV-infected patients without GBS and 91 non-ZIKV controls. Positive sera were taken forward for target identification by immunoprecipitation and mass spectrometry, and candidate antigens were validated by ELISA and cell-based assays. Autoantibody reactions against glycolipid antigens were also screened on an array. RESULTS: Overall, IgG antibody reactivities to rat Schwann cells (SCs) (6.5%) and myelinated cocultures (9.6%) were significantly higher, albeit infrequent, in the ZIKV-GBS group compared with all controls. IgM antibody immunoreactivity to dorsal root ganglia neurones (32.3%) and SCs (19.4%) was more frequently observed in the ZIKV-GBS group compared with other controls, whereas IgM reactivity to cocultures was as common in ZIKV and non-ZIKV sera. Strong axonal-binding ZIKV-GBS serum IgG antibodies from 1 patient were confirmed to react with neurofascin 155 and 186. Serum from a ZIKV-infected patient without GBS displayed strong myelin-binding and putative antilipid antigen reaction characteristics. There was, however, no significant association of ZIKV-GBS with any known antiglycolipid antibodies. DISCUSSION: Autoantibody responses in ZIKV-GBS target heterogeneous peripheral nerve antigens suggesting heterogeneity of the humoral immune response despite a common prodromal infection.

A Rapid RT-LAMP Assay for SARS-CoV-2 with Colorimetric Detection Assisted by a Mobile Application.

Loop-mediated amplification has been promoted for SARS-CoV-2 screening, however, antigen tests are preferred in low-income countries and remote zones. Poor training in molecular biology, plus the need for RNA purification or reading instruments to overcome issues of sensitivity in colorimetric detection, are some of the reasons limiting the use of this technique. In this study, nasopharyngeal swabs, aspirates and saliva were amplified in an in-house LAMP assay and subject to colorimetric detection, achieved by the naked eye and by image analysis with a mobile application. Accuracy of detection by the naked eye ranged from 61-74% but improved to 75-86% when using the application. Sensitivity of the digital approach was 81% and specificity 83%, with poor positive predictive value, and acceptable negative predictive value. Additionally to the reported effect of some transport media's pH, the presence of mucus and warming up of reagents while setting up the reaction critically affected performance. Accuracy per type of sample was 55, 70 and 80%, for swabs, aspirates and saliva, respectively, suggesting potential to improve the test in saliva. This assay, carried out in a closed tube, reduces contamination, has few pipetting steps and requires minimal equipment. Strategies to improve performance and implications of the use this sort of colorimetric LAMP for massive testing are discussed.

Dynamic accessibility by car to tertiary care emergency services in Cali, Colombia, in 2020: cross-sectional equity analyses using travel time big data from a Google API.

OBJECTIVES: To test a new approach to characterise accessibility to tertiary care emergency health services in urban Cali and assess the links between accessibility and sociodemographic factors relevant to health equity. DESIGN: The impact of traffic congestion on accessibility to tertiary care emergency departments was studied with an equity perspective, using a web-based digital platform that integrated publicly available digital data, including sociodemographic characteristics of the population and places of residence with travel times. SETTING AND PARTICIPANTS: Cali, Colombia (population 2.258 million in 2020) using geographic and sociodemographic data. The study used predicted travel times downloaded for a week in July 2020 and a week in November 2020. PRIMARY AND SECONDARY OUTCOMES: The share of the population within a 15 min journey by car from the place of residence to the tertiary care emergency department with the shortest journey (ie, 15 min accessibility rate (15mAR)) at peak-traffic congestion hours. Sociodemographic characteristics were disaggregated for equity analyses. A time-series bivariate analysis explored accessibility rates versus housing stratification. RESULTS: Traffic congestion sharply reduces accessibility to tertiary emergency care (eg, 15mAR was 36.8% during peak-traffic hours vs 84.4% during free-flow hours for the week of 6-12 July 2020). Traffic congestion sharply reduces accessibility to tertiary emergency care. The greatest impact fell on specific ethnic groups, people with less educational attainment and those living in low-income households or on the periphery of Cali (15mAR: 8.1% peak traffic vs 51% free-flow traffic). These populations face longer average travel times to health services than the average population. CONCLUSIONS: These findings suggest that health services and land use planning should prioritise travel times over travel distance and integrate them into urban planning. Existing technology and data can reveal inequities by integrating sociodemographic data with accurate travel times to health services estimates, providing the basis for valuable indicators.

Dynamic geographical accessibility assessments to improve health equity: protocol for a test case in Cali, Colombia.

This protocol proposes an approach to assessing the place of residence as a spatial determinant of health in cities where traffic congestion might impact health services accessibility. The study provides dynamic travel times presenting data in ways that help shape decisions and spur action by diverse stakeholders and sectors.  Equity assessments in geographical accessibility to health services typically rely on static metrics, such as distance or average travel times. This new approach uses dynamic spatial accessibility measures providing travel times from the place of residence to the health service with the shortest journey time. It will show the interplay between traffic congestion, accessibility, and health equity and should be used to inform urban and health services monitoring and planning. Available digitised data enable efficient and accurate accessibility measurements for urban areas using publicly available sources and provide disaggregated sociodemographic information and an equity perspective. Test cases are done for urgent and frequent care (i.e., repeated ambulatory care). Situational analyses will be done with cross-sectional urban assessments; estimated potential improvements will be made for one or two new services, and findings will inform recommendations and future studies. This study will use visualisations and descriptive statistics to allow non-specialized stakeholders to understand the effects of accessibility on populations and health equity. This includes "time-to-destination" metrics or the proportion of the people that can reach a service by car within a given travel time threshold from the place of residence. The study is part of the AMORE Collaborative Project, in which a diverse group of stakeholders seeks to address equity for accessibility to essential health services, including health service users and providers, authorities, and community members, including academia.

Sentinel network for monitoring in vitro susceptibility of Plasmodium falciparum to antimalarial drugs in Colombia: a proof of concept.

Drug resistance is one of the principal obstacles blocking worldwide malaria control. In Colombia, malaria remains a major public health concern and drug-resistant parasites have been reported. In vitro drug susceptibility assays are a useful tool for monitoring the emergence and spread of drug-resistant Plasmodium falciparum. The present study was conducted as a proof of concept for an antimalarial drug resistance surveillance network based on in vitro susceptibility testing in Colombia. Sentinel laboratories were set up in three malaria endemic areas. The enzyme linked immunosorbent assay-histidine rich protein 2 and schizont maturation methods were used to assess the susceptibility of fresh P. falciparum isolates to six antimalarial drugs. This study demonstrates that an antimalarial drug resistance surveillance network based on in vitro methods is feasible in the field with the participation of a research institute, local health institutions and universities. It could also serve as a model for a regional surveillance network. Preliminary susceptibility results showed widespread chloroquine resistance, which was consistent with previous reports for the Pacific region. However, high susceptibility to dihydroartemisinin and lumefantrine compounds, currently used for treatment in the country, was also reported. The implementation process identified critical points and opportunities for the improvement of network sustainability strategies.

In vivo parasitological measures of artemisinin susceptibility.

Parasite clearance data from 18,699 patients with falciparum malaria treated with an artemisinin derivative in areas of low (n=14,539), moderate (n=2077), and high (n=2083) levels of malaria transmission across the world were analyzed to determine the factors that affect clearance rates and identify a simple in vivo screening measure for artemisinin resistance. The main factor affecting parasite clearance time was parasite density on admission. Clearance rates were faster in high-transmission settings and with more effective partner drugs in artemisinin-based combination treatments (ACTs). The result of the malaria blood smear on day 3 (72 h) was a good predictor of subsequent treatment failure and provides a simple screening measure for artemisinin resistance. Artemisinin resistance is highly unlikely if the proportion of patients with parasite densities of <100,000 parasites/microL given the currently recommended 3-day ACT who have a positive smear result on day 3 is <3%; that is, for n patients the observed number with a positive smear result on day 3 does not exceed (n + 60)/24.