ABSTRACT
The human microbiome is an integral component of the human body and a co-determinant of several health conditions1,2. However, the extent to which interpersonal relations shape the individual genetic makeup of the microbiome and its transmission within and across populations remains largely unknown3,4. Here, capitalizing on more than 9,700 human metagenomes and computational strain-level profiling, we detected extensive bacterial strain sharing across individuals (more than 10 million instances) with distinct mother-to-infant, intra-household and intra-population transmission patterns. Mother-to-infant gut microbiome transmission was considerable and stable during infancy (around 50% of the same strains among shared species (strain-sharing rate)) and remained detectable at older ages. By contrast, the transmission of the oral microbiome occurred largely horizontally and was enhanced by the duration of cohabitation. There was substantial strain sharing among cohabiting individuals, with 12% and 32% median strain-sharing rates for the gut and oral microbiomes, and time since cohabitation affected strain sharing more than age or genetics did. Bacterial strain sharing additionally recapitulated host population structures better than species-level profiles did. Finally, distinct taxa appeared as efficient spreaders across transmission modes and were associated with different predicted bacterial phenotypes linked with out-of-host survival capabilities. The extent of microorganism transmission that we describe underscores its relevance in human microbiome studies5, especially those on non-infectious, microbiome-associated diseases.
Subject(s)
Bacteria , Disease Transmission, Infectious , Gastrointestinal Microbiome , Home Environment , Microbiota , Mouth , Female , Humans , Infant , Bacteria/classification , Bacteria/genetics , Bacteria/isolation & purification , Gastrointestinal Microbiome/genetics , Metagenome , Microbiota/genetics , Mothers , Mouth/microbiology , Infectious Disease Transmission, Vertical , Family Characteristics , Aging , Time Factors , Microbial ViabilityABSTRACT
Introduction: Infection due to Capnocytophaga canimorsus may result in a wide variety of clinical presentations. We present a case of life-threatening Capnocytophaga canimorsus infection with evolution of ecchymosis to purpura fulminans. Case description: We present a case of a 43-year-old male with a history of excessive alcohol consumption who presented with features of sepsis following a dog bite. This was associated with a striking, widespread purpuric rash. A causative pathogen, C. canimorsus was identified through blood culture and 16S RNA sequencing. His initially purpuric rash underwent bullous transformation and was diagnosed clinically as purpura fulminans, confirmed on skin biopsy. He made a full recovery with prompt antimicrobial therapy, initially with co-amoxiclav but escalated to clindamycin and meropenem due to clinical deterioration and concerns of beta-lactamase resistance. Discussion: ß-Lactamase producing Capnocytophaga strains are of increasing concern. This particular concern is reflected in our case as 5 days into treatment with ß-lactamase inhibitor combination therapy the patients clinical condition deteriorated but demonstrably improved on switching to a carbapenem.The development of biopsy proven purpura fulminans in this immunocompetent case is a rare severe manifestation of the previously reported manifestation of disseminated intravascular coagulation (DIC) in Capnocytophaga bacteraemia. The case reported describes characteristics common with other DIC presentations such as the presence of clinical risk factors (history of excessive alcohol consumption) and symmetrical involvement. However, an unusual feature in that initial purpuric lesions were followed by the development of a bullous appearance and peripheral necrotic features concerning for purpura fulminans and confirmed with skin biopsy.
ABSTRACT
OBJECTIVES: To study the mortality of patients with COVID-19 in Sierra Leone, to explore the factors associated with mortality during the COVID-19 pandemic and to highlight the complexities of treating patients with a novel epidemic disease in a fragile health system. STUDY DESIGN: A prospective single-centre cohort study. Data were extracted from paper medical records and transferred onto an electronic database. Specific indicators were compared between survivors and non-survivors, using descriptive statistics in Stata V.17. STUDY SETTING: The infectious diseases unit (IDU) at Connaught Hospital in Freetown, Sierra Leone PARTICIPANTS: Participants were all patients admitted to the IDU between March and July 2020. AIMS OF STUDY: The primary outcome of the study was to examine the all-cause mortality of hospitalised patients with suspected COVID-19 in Sierra Leone and the secondary outcome measures were to examine factors associated with mortality in patients positive for COVID-19. RESULTS: 261 participants were included in the study. Overall, 41.3% of those admitted to the IDU died, compared with prepandemic in-hospital mortality of 23.8%. Factors contributing to the higher mortality were COVID-19 infection (aOR 5.61, 95% CI 1.19 to 26.30, p=0.02) and hypertension (aOR 9.30, 95% CI 1.18 to 73.27, p=0.03) CONCLUSIONS: This study explores the multiple factors underpinning a doubling in facility mortality rate during the COVID-19 pandemic in Sierra Leone . It provides an insight into the realities of providing front-line healthcare during a pandemic in a fragile health system.
Subject(s)
COVID-19 , Humans , Prospective Studies , Cohort Studies , Pandemics , Sierra LeoneABSTRACT
Asylum-seekers and refugees have an increased burden of infections compared with the general population. This has been widely recognised by countries welcoming those fleeing conflict and persecution; however, there are no screening standardised guidelines and regulatory processes. Identification of certain neglected tropical diseases (NTDs) and other infections is important for the health and well-being of the individual in addition to public health and biosecurity. In the United Kingdom, screening for infections at port of entry or after arrival is not mandatory. Those on refugee resettlement programmes will have infection screening as part of their pre-entry health assessment, but no such system exists for those claiming asylum in the United Kingdom. In this article, we have reviewed published, peer-reviewed articles looking at the approaches to screening for NTDs and infectious diseases in the United Kingdom. In addition to this, we have reviewed the literature looking at the acceptability, barriers and facilitators of these screening practices. We found that there is a heterogeneous approach to screening practices in the United Kingdom and a paucity of data to support a single 'best practice' approach. Based on our findings, we have made recommendations and consideration for NTD screening strategies and highlighted important areas for future research.
ABSTRACT
We present the case of a patient admitted to hospital in septic shock. He had a history of tricuspid valve infective endocarditis (IE) 6 months prior and regularly injected intravenous drugs. A bedside echo on arrival confirmed vegetations on his tricuspid valve, torrential tricuspid regurgitation and signs of significantly raised right-sided pressures. The admission chest radiograph showed consolidative changes in the lungs, suggestive of septic pulmonary emboli. He was commenced on antibiotics and treated in the high-dependency unit. He subsequently developed an acutely ischaemic right foot and nasal tip. Suspicions were raised of a paradoxical septic embolus through a right-to-left shunt, subsequently confirmed on bubble echo which showed passage of agitated saline between the atria. This was not apparent clinically or on echocardiogram during his previous episode of tricuspid valve IE, raising the possibility of the development of an acquired inter-atrial communication since his previous episode.
Subject(s)
Endocarditis/complications , Heart Atria/physiopathology , Pulmonary Embolism/etiology , Sepsis/etiology , Tricuspid Valve Insufficiency/complications , Tricuspid Valve/physiopathology , Computed Tomography Angiography , Echocardiography , Fatal Outcome , Foramen Ovale, Patent/physiopathology , Humans , MaleABSTRACT
Soil-transmitted helminths (STH) are endemic and widespread across Sub-Saharan Africa. A community wide soil-transmitted helminth (STH) prevalence survey was performed on the island of Bubaque in Guinea-Bissau using both Kato-katz microscopy and qPCR methodology. Predictors of infection and morbidity indicators were identified using multivariable logistic regression, and diagnostic methods were compared using k statistics. Among 396 participants, prevalence of STH by microscopy was 23.2%, hookworm was the only species identified by this method and the mean infection intensity was 312 eggs per gram. qPCR analysis revealed an overall prevalence of any STH infection of 47.3%, with the majority A. duodenale (32.3%), followed by N. americanus (15.01%) and S. stercoralis (13.2%). A. lumbricoides, and T. trichiura infections were negligible, with a prevalence of 0.25% each. Agreement between diagnostic tests was k = 0.22, interpreted as fair agreement, and infection intensity measured by both methods was only minimally correlated (Rs = -0.03). STH infection overall was more common in females and adults aged 31-40. STH infection was associated with open defaecation, low socio-economic status and further distance to a water-source. The prevalence of anaemia (defined as a binary outcome by the WHO standards for age and sex) was 69.1%, and 44.2% of children were malnourished according to WHO child growth standards. Hookworm infection intensity by faecal egg count showed no statistically significant association with age (Rs 0.06) but S. Stercoralis infection intensity by qPCR cycle threshold was higher in pre-school aged children (Rs = 0.30, p-value 0.03) There was no statistically significant association between STH infection and anaemia (OR 1.0 p = 0.8), stunting (OR 1.9, p-value 0.5) and wasting (OR 2.0, p-value 0.2) in children. This study reveals a persistent reservoir of STH infection across the community, with high rates of anaemia and malnutrition, despite high-coverage of mebendazole mass-drug administration in pre-school children. This reflects the need for a new strategy to soil-transmitted helminth control, to reduce infections and ultimately eliminate transmission.