Background: One of the fastest spreading vector-borne diseases in tropical and subtropical regions is dengue, which generates cost overruns for public health entities. Several factors can influence the dynamics of dengue virus transmission: environmental and climatic (abundance of vectors), interactions between hosts (infections by asymptomatic individuals), and population immunological factors. Given these conditions, it is necessary to carry out theoretical studies based on meteorological factors and asymptomatic transmission that are associated with both the existence of the vector and its incidence, in order to provide a scientific basis for health entities in decision-making.Methods: A mathematical model based on nonlinear ordinary differential equations is proposed to interpret the dynamics of dengue transmission in humans coupled to the dynamics of the Aedes aegypti species, considering the population of symptomatic and asymptomatic infected humans and the effect of temperature variability. The basic reproduction number was found and some simulation results based on the Runge-Kutta numerical method were obtained.Results: The simulations showed that the temperature had a directly proportional relationship with the basic reproduction number. The cases of infected people and carrier mosquitoes increased when the temperature peaks increased drastically; in low temperatures the infection persisted with low morbidity due to the survival of asymptomatic people.Conclusions: High temperatures tolerable by mosquitoes increase their life expectancy and their numbers in the environment which, together with a reservoir of asymptomatic infected people, leads to a higher incidence of the dengue virus in certain seasons or maintains its circulation in seasons of low temperatures, despite lower vector survival rates.
Abstract Background Organ transplantation from donors with human immunodeficiency virus (HIV) to recipients with HIV (HIV D+/R+) presents risks of donor-derived infections. Understanding clinical, immunologic, and virologic characteristics of HIV-positive donors is critical for safety. Methods We performed a prospective study of donors with HIV-positive and HIV false-positive (FP) test results within the HIV Organ Policy Equity (HOPE) Act in Action studies of HIV D+/R+ transplantation (ClinicalTrials.gov NCT02602262, NCT03500315, and NCT03734393). We compared clinical characteristics in HIV-positive versus FP donors. We measured CD4 T cells, HIV viral load (VL), drug resistance mutations (DRMs), coreceptor tropism, and serum antiretroviral therapy (ART) detection, using mass spectrometry in HIV-positive donors. Results Between March 2016 and March 2020, 92 donors (58 HIV positive, 34 FP), representing 98.9% of all US HOPE donors during this period, donated 177 organs (131 kidneys and 46 livers). Each year the number of donors increased. The prevalence of hepatitis B (16% vs 0%), syphilis (16% vs 0%), and cytomegalovirus (CMV; 91% vs 58%) was higher in HIV-positive versus FP donors; the prevalences of hepatitis C viremia were similar (2% vs 6%). Most HIV-positive donors (71%) had a known HIV diagnosis, of whom 90% were prescribed ART and 68% had a VL <400 copies/mL. The median CD4 T-cell count (interquartile range) was 194/µL (77–331/µL), and the median CD4 T-cell percentage was 27.0% (16.8%–36.1%). Major HIV DRMs were detected in 42%, including nonnucleoside reverse-transcriptase inhibitors (33%), integrase strand transfer inhibitors (4%), and multiclass (13%). Serum ART was detected in 46% and matched ART by history. Conclusion The use of HIV-positive donor organs is increasing. HIV DRMs are common, yet resistance that would compromise integrase strand transfer inhibitor–based regimens is rare, which is reassuring regarding safety.
La anemia preoperatoria, la reintervención por sangrado y la necesidad de transfusión son problemas frecuentes en los pacientes tratados con una cirugía cardiaca mayor y se asocian a un aumento considerable de la morbimortalidad. El objetivo del presente trabajo es analizar nuestros resultados quirúrgicos tras la aplicación de un programa de patient blood management (PBM), poniendo el foco en los parámetros hematológicos. Entre marzo de 2021 y mayo de 2022 hemos intervenido consecutivamente a 104 pacientes de cirugía cardiaca mayor con el programa PBM. La edad media fue de 65 ± 11 años, el 66% fueron varones, el 21% tenían un EuroScore II > 5, el 24% anemia preoperatoria y el 2,8% eran testigos de Jehová que rechazaban las transfusiones. El 19,2% de los procedimientos fueron coronarios sin circulación extracorpórea; el 8,7%, endocarditis; el 10,6%, reintervenciones; el 2,9%, síndromes aórticos agudos y el 34% fueron cirugías urgentes o emergentes. La tasa de reoperación por sangrado fue del 1,9% y la de transfusión perioperatoria del 25%. El 87,5% de los pacientes operados de forma electiva y el 90,5% de los coronarios aislados no recibieron hemocomponentes. El número medio de concentrados de hematíes (índice de transfusión total), unidades de plasma fresco congelado y concentrados de plaquetas transfundidos por paciente fue de 0,47; 0,16 y 0,07, respectivamente. El PBM nos ha permitido alcanzar nuestros objetivos de calidad en cuanto a reintervención por sangrado y tasa de transfusión perioperatoria. Preoperative anemia, reexploration for bleeding and need for transfusion are common problems in patients undergoing mayor cardiac surgery and are associated with an increase morbidity and mortality. The objective of the present report is to evaluate our surgical results focusing on hematological parameters after the implementation of a Patient Blood Management (PBM) program. Between March 2021 and May 2022, we have consecutively operated on 104 mayor cardiac surgery patients with the PBM program. The mean patient age was 65 ± 11 years, 66% of the patients were male, 21% had a EuroScore II > 5, 24% had preoperative anemia, and 2,8% were Jehovah's Witnesses who refused transfusions. The 19,2% of the procedures were off-pump coronary artery bypass grafting, 8,7% endocarditis, 10,6% redo operations, 2,9% acute aortic syndromes, and 34% urgent or emergent cases. The incidence of reexploration for bleeding was 1,9% and the perioperative transfusion rate was 25%; 87,5% of the patients operated on electively and 90,5% of the isolated coronary patients did not receive blood components. The mean number of red blood cell concentrates (total transfusion index), fresh frozen plasma, and pooled platelets transfused per patient was 0.47, 0.16, and 0.07, respectively. The PBM has allowed us to achieve our quality objectives in terms of reintervention for bleeding and perioperative transfusion rate.
Abstract During 2001–2007, to determine incidence of all hantavirus infections, including those without pulmonary syndrome, in western Panama, we conducted 11 communitywide surveys. Among 1,129 persons, antibody prevalence was 16.5%–60.4%. Repeat surveys of 476 found that patients who seroconverted outnumbered patients with hantavirus pulmonary syndrome by 14 to 1.
