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1.
Cell ; 184(18): 4772-4783.e15, 2021 09 02.
Artículo en Inglés | MEDLINE | ID: mdl-34388390

RESUMEN

Throughout development and aging, human cells accumulate mutations resulting in genomic mosaicism and genetic diversity at the cellular level. Mosaic mutations present in the gonads can affect both the individual and the offspring and subsequent generations. Here, we explore patterns and temporal stability of clonal mosaic mutations in male gonads by sequencing ejaculated sperm. Through 300× whole-genome sequencing of blood and sperm from healthy men, we find each ejaculate carries on average 33.3 ± 12.1 (mean ± SD) clonal mosaic variants, nearly all of which are detected in serial sampling, with the majority absent from sampled somal tissues. Their temporal stability and mutational signature suggest origins during embryonic development from a largely immutable stem cell niche. Clonal mosaicism likely contributes a transmissible, predicted pathogenic exonic variant for 1 in 15 men, representing a life-long threat of transmission for these individuals and a significant burden on human population health.


Asunto(s)
Crecimiento y Desarrollo , Mosaicismo , Espermatozoides/metabolismo , Adolescente , Envejecimiento/sangre , Alelos , Células Clonales , Estudios de Cohortes , Humanos , Masculino , Modelos Biológicos , Mutación/genética , Factores de Riesgo , Factores de Tiempo , Adulto Joven
2.
BMC Microbiol ; 24(1): 115, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38575867

RESUMEN

Despite repeated spillover transmission and their potential to cause significant morbidity and mortality in human hosts, the New World mammarenaviruses remain largely understudied. These viruses are endemic to South America, with animal reservoir hosts covering large geographic areas and whose transmission ecology and spillover potential are driven in part by land use change and agriculture that put humans in regular contact with zoonotic hosts.We compiled published studies about Guanarito virus, Junin virus, Machupo virus, Chapare virus, Sabia virus, and Lymphocytic Choriomeningitis virus to review the state of knowledge about the viral hemorrhagic fevers caused by New World mammarenaviruses. We summarize what is known about rodent reservoirs, the conditions of spillover transmission for each of these pathogens, and the characteristics of human populations at greatest risk for hemorrhagic fever diseases. We also review the implications of repeated outbreaks and biosecurity concerns where these diseases are endemic, and steps that countries can take to strengthen surveillance and increase capacity of local healthcare systems. While there are unique risks posed by each of these six viruses, their ecological and epidemiological similarities suggest common steps to mitigate spillover transmission and better contain future outbreaks.


Asunto(s)
Arenaviridae , Arenavirus del Nuevo Mundo , Animales , Humanos , Arenaviridae/genética , América del Sur
3.
J Anim Ecol ; 2024 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-39004905

RESUMEN

Interspecific interactions are highly relevant in the potential transmission of shared pathogens in multi-host systems. In recent decades, several technologies have been developed to study pathogen transmission, such as proximity loggers, GPS tracking devices and/or camera traps. Despite the diversity of methods aimed at detecting contacts, the analysis of transmission risk is often reduced to contact rates and the probability of transmission given the contact. However, the latter process is continuous over time and unique for each contact, and is influenced by the characteristics of the contact and the pathogen's relationship with both the host and the environment. Our objective was to assess whether a more comprehensive approach, using a movement-based model which assigns a unique transmission risk to each contact by decomposing transmission into contact formation, contact duration and host characteristics, could reveal disease transmission dynamics that are not detected with more traditional approaches. The model was built from GPS-collar data from two management systems in Spain where animal tuberculosis (TB) circulates: a national park with extensively reared endemic cattle, and an area with extensive free-range pigs and cattle farms. In addition, we evaluated the effect of the GPS device fix rate on the performance of the model. Different transmission dynamics were identified between both management systems. Considering the specific conditions under which each contact occurs (i.e. whether the contact is direct or indirect, its duration, the hosts characteristics, the environmental conditions, etc.) resulted in the identification of different transmission dynamics compared to using only contact rates. We found that fix intervals greater than 30 min in the GPS tracking data resulted in missed interactions, and intervals greater than 2 h may be insufficient for epidemiological purposes. Our study shows that neglecting the conditions under which each contact occurs may result in a misidentification of the real role of each species in disease transmission. This study describes a clear and repeatable framework to study pathogen transmission from GPS data and provides further insights to understand how TB is maintained in multi-host systems in Mediterranean environments.

4.
Proc Natl Acad Sci U S A ; 118(8)2021 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-33536312

RESUMEN

Several lines of existing evidence support the possibility of airborne transmission of coronavirus disease 2019 (COVID-19). However, quantitative information on the relative importance of transmission pathways of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains limited. To evaluate the relative importance of multiple transmission routes for SARS-CoV-2, we developed a modeling framework and leveraged detailed information available from the Diamond Princess cruise ship outbreak that occurred in early 2020. We modeled 21,600 scenarios to generate a matrix of solutions across a full range of assumptions for eight unknown or uncertain epidemic and mechanistic transmission factors. A total of 132 model iterations met acceptability criteria (R2 > 0.95 for modeled vs. reported cumulative daily cases and R2 > 0 for daily cases). Analyzing only these successful model iterations quantifies the likely contributions of each defined mode of transmission. Mean estimates of the contributions of short-range, long-range, and fomite transmission modes to infected cases across the entire simulation period were 35%, 35%, and 30%, respectively. Mean estimates of the contributions of larger respiratory droplets and smaller respiratory aerosols were 41% and 59%, respectively. Our results demonstrate that aerosol inhalation was likely the dominant contributor to COVID-19 transmission among the passengers, even considering a conservative assumption of high ventilation rates and no air recirculation conditions for the cruise ship. Moreover, close-range and long-range transmission likely contributed similarly to disease progression aboard the ship, with fomite transmission playing a smaller role. The passenger quarantine also affected the importance of each mode, demonstrating the impacts of the interventions.


Asunto(s)
Aerosoles , COVID-19/transmisión , Brotes de Enfermedades/estadística & datos numéricos , Modelos Teóricos , Cuarentena/normas , SARS-CoV-2/aislamiento & purificación , Navíos/estadística & datos numéricos , COVID-19/diagnóstico , COVID-19/prevención & control , COVID-19/virología , Humanos , Cuarentena/métodos , Cuarentena/estadística & datos numéricos
5.
Risk Anal ; 44(3): 631-640, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37317640

RESUMEN

The risk assessments during the COVID-19 pandemic were primarily based on dose-response models derived from the pooled datasets for infection of animals susceptible to SARS-CoV. Despite similarities, differences in susceptibility between animals and humans exist for respiratory viruses. The two most commonly used dose-response models for calculating the infection risk of respiratory viruses are the exponential and the Stirling approximated ß-Poisson (BP) models. The modified version of the one-parameter exponential model or the Wells-Riley model was almost solely used for infection risk assessments during the pandemic. Still, the two-parameter (α and ß) Stirling approximated BP model is often recommended compared to the exponential dose-response model due to its flexibility. However, the Stirling approximation restricts this model to the general rules of ߠ≫ 1 and α â‰ª ß, and these conditions are very often violated. To refrain from these requirements, we tested a novel BP model by using the Laplace approximation of the Kummer hypergeometric function instead of the conservative Stirling approximation. The datasets of human respiratory airborne viruses available in the literature for human coronavirus (HCoV-229E) and human rhinovirus (HRV-16 and HRV-39) are used to compare the four dose-response models. Based on goodness-of-fit criteria, the exponential model was the best fitting model for the HCoV-229E (k = 0.054) and for HRV-39 datasets (k = 1.0), whereas the Laplace approximated BP model followed by the exact and Stirling approximated BP models are preferred for both the HRV-16 (α = 0.152 and ß = 0.021 for Laplace BP) and the HRV-16 and HRV-39 pooled datasets (α = 0.2247 and ß = 0.0215 for Laplace BP).


Asunto(s)
COVID-19 , Coronavirus Humano 229E , Animales , Humanos , Rhinovirus , Pandemias , Medición de Riesgo
6.
Clin Genet ; 103(5): 540-552, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36762955

RESUMEN

Genetic testing and management of individuals at risk for NF2-related schwannomatosis is complicated by the high rate of mosaicism resulting in a milder, later onset, more asymmetrical disease and the phenotypic overlap with the related schwannomatosis conditions. This updated protocol has been devised for the English NF2-related schwannomatosis service. It provides those affected with mosaic NF2-related schwannomatosis estimated risks of having an affected child; and management guidelines both for individuals at risk of NF2-related schwannomatosis, or with potential disease, due to having features that fall short of consensus diagnostic criteria. Risks of mosaicism and inferred transmission risks were derived from genetic testing of over 1000 individuals through the Manchester NF2 genetic testing service. This updated protocol, reflects the lower transmission risks now inferred in mosaic NF2-related schwannomatosis, informed by the greater sensitivity of Next Generation Sequencing in detecting low levels of mosaicism in blood, along with improved ability to analyse tumour DNA. Screening for features of NF2-related schwannomatosis is proposed until the risk of having the condition falls below a pragmatic threshold of 1%. Using these revised transmission figures, this threshold can now be reached at a younger age in many of those at risk, with earlier reassurance and discharge.


Asunto(s)
Neurilemoma , Neurofibromatosis , Neurofibromatosis 2 , Neoplasias Cutáneas , Niño , Humanos , Neurofibromatosis/diagnóstico , Neurofibromatosis/genética , Neurofibromatosis/patología , Neurilemoma/diagnóstico , Neurilemoma/genética , Neurilemoma/patología , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología , Pruebas Genéticas , Neurofibromatosis 2/diagnóstico , Neurofibromatosis 2/genética , Neurofibromatosis 2/terapia
7.
Glob Chang Biol ; 29(13): 3723-3746, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37026556

RESUMEN

Climate has critical roles in the origin, pathogenesis and transmission of infectious zoonotic diseases. However, large-scale epidemiologic trend and specific response pattern of zoonotic diseases under future climate scenarios are poorly understood. Here, we projected the distribution shifts of transmission risks of main zoonotic diseases under climate change in China. First, we shaped the global habitat distribution of main host animals for three representative zoonotic diseases (2, 6, and 12 hosts for dengue, hemorrhagic fever, and plague, respectively) with 253,049 occurrence records using maximum entropy (Maxent) modeling. Meanwhile, we predicted the risk distribution of the above three diseases with 197,098 disease incidence records from 2004 to 2017 in China using an integrated Maxent modeling approach. The comparative analysis showed that there exist highly coincident niche distributions between habitat distribution of hosts and risk distribution of diseases, indicating that the integrated Maxent modeling is accurate and effective for predicting the potential risk of zoonotic diseases. On this basis, we further projected the current and future transmission risks of 11 main zoonotic diseases under four representative concentration pathways (RCPs) (RCP2.6, RCP4.5, RCP6.0, and RCP8.5) in 2050 and 2070 in China using the above integrated Maxent modeling with 1,001,416 disease incidence records. We found that Central China, Southeast China, and South China are concentrated regions with high transmission risks for main zoonotic diseases. More specifically, zoonotic diseases had diverse shift patterns of transmission risks including increase, decrease, and unstable. Further correlation analysis indicated that these patterns of shifts were highly correlated with global warming and precipitation increase. Our results revealed how specific zoonotic diseases respond in a changing climate, thereby calling for effective administration and prevention strategies. Furthermore, these results will shed light on guiding future epidemiologic prediction of emerging infectious diseases under global climate change.


Asunto(s)
Epidemias , Zoonosis , Animales , Incidencia , Zoonosis/epidemiología , Ecosistema , Cambio Climático , China/epidemiología
8.
J Theor Biol ; 575: 111635, 2023 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-37858903

RESUMEN

To estimate the risk of human immunodeficiency virus (HIV) infection through sexual transmission in China from 2013 to 2017 accurately, we divide the total population into three groups, namely, men who have sex with men (MSM) group; non-marital and commercial sex group: female sex workers (FSW) and their clients (FSWC); non-marital and non-commercial sex group: general women (GW) and general men (GM). First, the risks of HIV infection among men who have contacts with infected men or infected women decrease annually. Second, the number of contacts between susceptible FSWC and infected FSW per unit time is greater than that between susceptible MSM and infected MSM, and also greater than that between susceptible FSW and infected FSWC, which suggests that the intervention for commercial sex of heterosexual men should be strengthened. Third, the effective reproduction numbers of the MSM group and non-commercial sex group decrease annually, while the effective reproduction number of the commercial sex group decreases first, then increases, because the risk of women being infected by men decreases first, then increases. Additionally, the effective reproduction number of the commercial sex group exceeds that of the MSM group after 2015, which indicates that commercial sex contributes more and more to the HIV/AIDS epidemic.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , Infecciones por VIH , Trabajadores Sexuales , Minorías Sexuales y de Género , Masculino , Humanos , Femenino , Infecciones por VIH/epidemiología , Homosexualidad Masculina , Trabajo Sexual , Síndrome de Inmunodeficiencia Adquirida/epidemiología , China/epidemiología , Medición de Riesgo , Conducta Sexual
9.
Environ Res ; 238(Pt 1): 117156, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37717799

RESUMEN

The rapid spread of Coronavirus Disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has emphasized the importance of understanding and adapting to the indoor remediation of transmissible diseases to decrease the risk for future pandemic threats. While there were many precautions in place to hinder the spread of COVID-19, there has also been a substantial increase of new research on SARS-CoV-2 that can be utilized to further mitigate the transmission risk of this novel virus. This review paper aims to identify the building parameters of indoor spaces that could have considerable influence on the transmission of SARS-CoV-2. The following building parameters have been identified and analyzed, emphasizing their link with the indoor transmission of SARS-CoV-2: temperature and relative humidity, temperature differences between rooms, ventilation rate and access to natural ventilation, occupant density, surface type and finish, airflow direction and speed, air stability, indoor air pollution, central air conditioning systems, capacity of air handling system and HVAC filter efficiency, edge sealing of air filters, room layout and interior design, and compartmentalization of interior space. This paper also explains the interactions of SARS-CoV-2 with indoor environments and its persistence. Furthermore, the modifications of the key building parameters have been discussed for controlling the transmission of SARS-CoV-2 in indoor spaces. Understanding the information provided in this paper is crucial to develop effective health and safety measures that will aid in infection prevention.


Asunto(s)
Contaminación del Aire Interior , COVID-19 , Humanos , SARS-CoV-2 , Contaminación del Aire Interior/prevención & control , Temperatura , Ventilación
10.
Global Health ; 19(1): 58, 2023 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-37592305

RESUMEN

BACKGROUND: Outbreaks of monkeypox have been ongoing in non-endemic countries since May 2022. A thorough assessment of its global zoonotic niche and potential transmission risk is lacking. METHODS: We established an integrated database on global monkeypox virus (MPXV) occurrence during 1958 - 2022. Phylogenetic analysis was performed to examine the evolution of MPXV and effective reproductive number (Rt) was estimated over time to examine the dynamic of MPXV transmissibility. The potential ecological drivers of zoonotic transmission and inter-regional transmission risks of MPXV were examined. RESULTS: As of 24 July 2022, a total of 49 432 human patients with MPXV infections have been reported in 78 countries. Based on 525 whole genome sequences, two main clades of MPXV were formed, of which Congo Basin clade has a higher transmissibility than West African clade before the 2022-monkeypox, estimated by the overall Rt (0.81 vs. 0.56), and the latter significantly increased in the recent decade. Rt of 2022-monkeypox varied from 1.14 to 4.24 among the 15 continuously epidemic countries outside Africa, with the top three as Peru (4.24, 95% CI: 2.89-6.71), Brazil (3.45, 95% CI: 1.62-7.00) and the United States (2.44, 95% CI: 1.62-3.60). The zoonotic niche of MPXV was associated with the distributions of Graphiurus lorraineus and Graphiurus crassicaudatus, the richness of Rodentia, and four ecoclimatic indicators. Besides endemic areas in Africa, more areas of South America, the Caribbean States, and Southeast and South Asia are ecologically suitable for the occurrence of MPXV once the virus has invaded. Most of Western Europe has a high-imported risk of monkeypox from Western Africa, whereas France and the United Kingdom have a potential imported risk of Congo Basin clade MPXV from Central Africa. Eleven of the top 15 countries with a high risk of MPXV importation from the main countries of 2022-monkeypox outbreaks are located at Europe with the highest risk in Italy, Ireland and Poland. CONCLUSIONS: The suitable ecological niche for MPXV is not limited to Africa, and the transmissibility of MPXV was significantly increased during the 2022-monkeypox outbreaks. The imported risk is higher in Europe, both from endemic areas and currently epidemic countries. Future surveillance and targeted intervention programs are needed in its high-risk areas informed by updated prediction.


Asunto(s)
Mpox , Humanos , Mpox/epidemiología , Filogenia , Brotes de Enfermedades , Estudios Retrospectivos , Brasil
11.
Proc Natl Acad Sci U S A ; 117(26): 14642-14644, 2020 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-32522870

RESUMEN

To prevent the spread of coronavirus disease 2019 (COVID-19), some types of public spaces have been shut down while others remain open. These decisions constitute a judgment about the relative danger and benefits of those locations. Using mobility data from a large sample of smartphones, nationally representative consumer preference surveys, and economic statistics, we measure the relative transmission reduction benefit and social cost of closing 26 categories of US locations. Our categories include types of shops, entertainments, and service providers. We rank categories by their trade-off of social benefits and transmission risk via dominance across 13 dimensions of risk and importance and through composite indexes. We find that, from February to March 2020, there were larger declines in visits to locations that our measures indicate should be closed first.


Asunto(s)
Conducta , Infecciones por Coronavirus/prevención & control , Transmisión de Enfermedad Infecciosa/prevención & control , Exposición por Inhalación/prevención & control , Modelos Estadísticos , Pandemias/prevención & control , Neumonía Viral/prevención & control , Prevención Primaria/estadística & datos numéricos , Cuarentena/estadística & datos numéricos , COVID-19 , Espacios Confinados , Trazado de Contacto/métodos , Trazado de Contacto/estadística & datos numéricos , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/transmisión , Costos y Análisis de Costo , Transmisión de Enfermedad Infecciosa/estadística & datos numéricos , Humanos , Exposición por Inhalación/estadística & datos numéricos , Museos , Neumonía Viral/epidemiología , Neumonía Viral/transmisión , Prevención Primaria/economía , Prevención Primaria/métodos , Cuarentena/economía , Cuarentena/métodos , Medición de Riesgo , Instituciones Académicas , Teléfono Inteligente/estadística & datos numéricos , Instalaciones Deportivas y Recreativas , Estados Unidos
12.
Sensors (Basel) ; 23(5)2023 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-36904663

RESUMEN

A healthy and safe indoor environment is an important part of containing the coronavirus disease 2019 (COVID-19) pandemic. Therefore, this work presents a real-time Internet of things (IoT) software architecture to automatically calculate and visualize a COVID-19 aerosol transmission risk estimation. This risk estimation is based on indoor climate sensor data, such as carbon dioxide (CO2) and temperature, which is fed into Streaming MASSIF, a semantic stream processing platform, to perform the computations. The results are visualized on a dynamic dashboard that automatically suggests appropriate visualizations based on the semantics of the data. To evaluate the complete architecture, the indoor climate during the student examination periods of January 2020 (pre-COVID) and January 2021 (mid-COVID) was analyzed. When compared to each other, we observe that the COVID-19 measures in 2021 resulted in a safer indoor environment.


Asunto(s)
Contaminación del Aire Interior , COVID-19 , Humanos , Contaminación del Aire Interior/análisis , Aerosoles y Gotitas Respiratorias , Programas Informáticos , Temperatura
13.
Energy Build ; 278: 112623, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36345312

RESUMEN

With increasing energy use and outbreaks of respiratory infectious diseases (such as COVID-19) in buildings, there is a growing interest in creating healthy and energy-efficient indoor environments. A novel heating system named low-temperature radiant floor coupled with intermittent stratum ventilation (LTR-ISV) is proposed in this study. Thermal performance, indoor air quality, energy and exergy performance were investigated and compared with conventional radiant floor heating (CRFH) and conventional radiant floor heating with mixing ventilation (CRFH + MV). The results indicated that LTR-ISV had a more uniform operative temperature distribution and overall thermal sensation, and air mixing was enhanced without generating additional draft sensation. Compared with CRFH and CRFH + MV, the indoor CO2 concentration in LTR-ISV can be reduced by 1355 ppm and 400 ppm, respectively. Airborne transmission risk can also be reduced by 5.35 times. The coefficient of performance for CRFH, CRFH + MV, and LTR-ISV during working hours was 4.2, 2.5, and 3.4, respectively. The lower value of LTR-ISV was due to the high energy usage of the primary air handing unit. In the non-working hours, LTR-ISV was 0.6 and 1.3 higher compared to CRFH and CRFH + MV, respectively. The exergy efficiency of LTR-ISV, CRFH, and CRFH + MV was 81.77 %, 76.43 %, and 64.71 %, respectively. Therefore, the LTR-ISV system can meet the requirements of high indoor air quality and thermal comfort and provides a reference for the energy-saving use of low-grade energy in space heating.

14.
Environ Res ; 203: 111831, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34352235

RESUMEN

The ongoing coronavirus 2019 (COVID-19) pandemic constitutes a concerning global threat to public health and economy. In the midst of this pandemic scenario, the role of environment-to-human COVID-19 spread is still a matter of debate because mixed results have been reported concerning SARS-CoV-2 stability on high-touch surfaces in real-life scenarios. Up to now, no alternative and accessible procedures for cell culture have been applied to evaluate SARS-CoV-2 infectivity on fomites. Several strategies based on viral capsid integrity have latterly been developed using viability markers to selectively remove false-positive qPCR signals resulting from free nucleic acids and damaged viruses. These have finally allowed an estimation of viral infectivity. The present study aims to provide a rapid molecular-based protocol for detection and quantification of viable SARS-CoV-2 from fomites based on the discrimination of non-infectious SARS-CoV-2 particles by platinum chloride (IV) (PtCl4) viability RT-qPCR. An initial assessment compared two different swabbing procedures to recover inactivated SARS-CoV-2 particles from fomites coupled with two RNA extraction methods. Procedures were validated with human (E229) and porcine (PEDV) coronavirus surrogates, and compared with inactivated SARS-CoV-2 suspensions on glass, steel and plastic surfaces. The viability RT-qPCR efficiently removed the PCR amplification signals from heat and gamma-irradiated inactivated SARS-CoV-2 suspensions that had been collected from specified surfaces. This study proposes a rapid viability RT-qPCR that discriminates non-infectious SARS-CoV-2 particles on surfaces thus helping researchers to better understand the risk of contracting COVID-19 through contact with fomites and to develop more efficient epidemiological measures.


Asunto(s)
COVID-19 , SARS-CoV-2 , Animales , Fómites , Humanos , Pandemias , ARN Viral , Porcinos
15.
Risk Anal ; 42(4): 692-706, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34549813

RESUMEN

The COVID-19 pandemic has called for and generated massive novel government regulations to increase social distancing for the purpose of reducing disease transmission. A number of studies have attempted to guide and measure the effectiveness of these policies, but there has been less focus on the overall efficiency of these policies. Efficient social distancing requires implementing stricter restrictions during periods of high viral prevalence and rationing social contact to disproportionately preserve gatherings that produce a good ratio of benefits to transmission risk. To evaluate whether U.S. social distancing policy actually produced an efficient social distancing regime, we tracked consumer preferences for, visits to, and crowding in public locations of 26 different types. We show that the United States' rationing of public spaces, postspring 2020, has failed to achieve efficiency along either dimension. In April 2020, the United States did achieve notable decreases in visits to public spaces and focused these reductions at locations that offer poor benefit-to-risk tradeoffs. However, this achievement was marred by an increase, from March to April, in crowding at remaining locations due to fewer locations remaining open. In December 2020, at the height of the pandemic so far, crowding in and total visits to locations were higher than in February, before the U.S. pandemic, and these increases were concentrated in locations with the worst value-to-risk tradeoff.


Asunto(s)
COVID-19 , Humanos , Pandemias , Distanciamiento Físico , Medición de Riesgo , Estados Unidos
16.
Build Environ ; 225: 109640, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36210963

RESUMEN

SARS-CoV-2 has been recognized to be airborne transmissible. With the large number of reported positive cases in the community, home quarantine is recommended for the infectors who are not severely ill. However, the risks of household aerosol transmission associated with the quarantine room operating methods are under-explored. We used tracer gas technique to simulate the exhaled virus laden aerosols from a patient under home quarantine situation inside a residential testbed. The Sulphur hexafluoride (SF6) concentration was measured both inside and outside the quarantine room under different operating settings including, air-conditioning and natural ventilation, presence of an exhaust fan, and the air movement generated by ceiling or pedestal fan. We calculated the outside-to-inside SF6 concentration to indicate potential exposure of occupants in the same household. In-room concentration with air-conditioning was 4 times higher than in natural ventilation settings. Exhaust fan operation substantially reduced in-room SF6 concentration and leakage rate in most of the ventilation scenarios, except for natural ventilation setting with ceiling fan. The exception is attributable to the different airflow patterns between ceiling fan (recirculates air vertically) and pedestal fan (moves air horizontally). These airflow variations also led to differences in SF6 concentration at two sampling heights (0.1 m and 1.7 m) and SF6 leakage rates when the quarantine room door was opened momentarily. Use of natural ventilation rather than air-conditioning, and operating exhaust fan when using air-conditioning are recommended to lower exposure risk for home quarantine. A more holistic experiment will be conducted to address the limitations reflected in this study.

17.
Build Environ ; 221: 109309, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-35757305

RESUMEN

The number of occupants in a space influences the risk of far-field airborne transmission of SARS-CoV-2 because the likelihood of having infectious and susceptible people both correlate with the number of occupants. This paper explores the relationship between occupancy and the probability of infection, and how this affects an individual person and a population of people. Mass-balance and dose-response models determine far-field transmission risks for an individual person and a population of people after sub-dividing a large reference space into 10 identical comparator spaces. For a single infected person, the dose received by an individual person in the comparator space is 10 times higher because the equivalent ventilation rate per infected person is lower when the per capita ventilation rate is preserved. However, accounting for population dispersion, such as the community prevalence of the virus, the probability of an infected person being present and uncertainty in their viral load, shows the transmission probability increases with occupancy and the reference space has a higher transmission risk. Also, far-field transmission is likely to be a rare event that requires a high emission rate, and there are a set of Goldilocks conditions that are just right when equivalent ventilation is effective at mitigating against transmission. These conditions depend on the viral load, because when they are very high or low, equivalent ventilation has little effect on transmission risk. Nevertheless, resilient buildings should deliver the equivalent ventilation rate required by standards as minimum.

18.
Przegl Epidemiol ; 76(3): 304-313, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36520041

RESUMEN

BACKGROUND: It is essential to deliver specialist human immunodeficiency virus (HIV) care with maximum effectiveness, but also minimum time delay. Therefore, we aimed to determine whether rapid linkage to care defined as starting combined antiretroviral therapy (cART) on the day of the first visit at the HIV clinic is a costeffective approach. METHODS: In the analysis, Markov's lifetime model presented in our previous study was implemented. The inputs used in the model were updated in the terms of costs, life expectancy, and patient characteristics. For the analysis we used information from the previous model about the additional costs of treatment and qualityadjusted life years (QALYs) lost in the life horizon for people newly infected with HIV. The number of newly infected persons was estimated based on available data. RESULTS: Input data was available for 344 men having sex with men (MSM) who registered in the HIV specialist care between 2016 and 2017. The estimated QALY loss due to lack of rapid treatment initiation, where the viral load is not (was) taken into account, equals 0·018 (0·022), 0·039 (0·047), 0·131 (0·158) respectively in low, medium and high risk transmission groups. Rapid cART initiation was dominant regardless of the chosen scenarios. CONCLUSIONS: Cost-effectiveness analysis considering the HIV transmission indicates that the rapid initiation of HIV treatment is a cost-effective and potentially cost-saving approach to improve HIV care and reduce HIV transmission in Central and Eastern Europe.


Asunto(s)
Infecciones por VIH , Minorías Sexuales y de Género , Masculino , Humanos , Homosexualidad Masculina , Infecciones por VIH/tratamiento farmacológico , Análisis Costo-Beneficio , Polonia , Años de Vida Ajustados por Calidad de Vida
19.
Vox Sang ; 116(10): 1094-1101, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33900632

RESUMEN

BACKGROUND AND OBJECTIVES: There is a growing concern for the transmission of arboviral infections by blood transfusion in Europe. However, no assessment of the risk of transmission through all European blood supplies has been reported. Risk regulations at a European level should take differences in local transmission risk and the risk of transmission by travelling donors into consideration. MATERIALS AND METHODS: A risk model and publicly available tool were developed to calculate the risk of transmission by all European blood supplies for arboviral outbreaks within Europe. Data on individual European blood supplies from Council of Europe reports and inter-European travel data from EUROSTAT were used to populate this model. RESULTS: Each neuroinvasive case of WNV reported in Europe will on average result in 0·43 (95%CI: 0·32-0·55) infected blood product by locally infected donors and 0·010 (95%CI: 0·006-0·015) infected products by travelling donors. On basis of the 1373 neuroinvasive human WNV cases reported in the outbreak of 2018, it is estimated that without safety interventions this outbreak would have resulted in 708 (95%CI: 523-922) infected components derived from resident donors. Noncompliance to European regulations, which requires donor deferral or testing of donors who visited WNV-infected areas, would have resulted in 7.4 (95%CI: 4·7-11·1) infected blood components derived from infectious travelling donors exposed in outbreak areas throughout Europe. CONCLUSION: The risk of WNV transmission by a local outbreak is on average 113 times (95%CI: 95-139), so two orders of magnitude higher than the risk of transmission by travelling donors in Europe.


Asunto(s)
Fiebre del Nilo Occidental , Virus del Nilo Occidental , Donantes de Sangre , Transfusión Sanguínea , Humanos , Viaje , Fiebre del Nilo Occidental/epidemiología
20.
AIDS Behav ; 25(10): 3047-3056, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33880670

RESUMEN

The relationships between depressive symptoms, viral suppression, and condomless sex were examined in a prospective cohort study of 369 HIV-positive Kenyan female sex workers. Participants were screened for depressive symptoms at baseline and every six months until completion of the study (up to 66 months). HIV viral load (VL) was measured every six months and prostate specific antigen (PSA) testing in vaginal secretions was performed quarterly. Mild or greater depressive symptoms were found in 100 (27.1%) women and were associated with increased risk of detectable VL (aRR 1.41, 95%CI 0.97-2.07, p-value = 0.07), but were not associated with detectable PSA. The co-occurrence of PSA detection and detectable VL at the same visit suggests the potential for HIV transmission but was uncommon (2.4% of visits). The prevalence of depressive symptoms and the association with detectable VL suggests the need for screening and treatment of depression for comprehensive HIV care in this population.


Asunto(s)
Infecciones por VIH , Trabajadores Sexuales , Depresión/epidemiología , Femenino , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Humanos , Kenia/epidemiología , Masculino , Estudios Prospectivos , Sexo Inseguro , Carga Viral
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