SARS-CoV-2 transmission dynamics in the urban-rural interface.

OBJECTIVES: As the world responds to the coronavirus outbreak, the role of public health in ensuring equitable health care that considers the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) dynamics in rural communities is still a challenge. The same suppression and mitigation measures have been implemented homogeneously, ignoring the differences between urban and rural areas. We propose an epidemiological model and simulate the dynamics of SARS-CoV-2 in urban and rural areas considering the interaction between these regions. STUDY DESIGN: This was a population modeling study. METHODS: A compartmental epidemiological model was formulated to simulate the transmission of SARS-CoV-2 in urban and rural areas. We use the model to investigate the impact of control strategies focused on the urban-rural interface to contain the epidemic size of SARS-CoV-2 in rural areas. RESULTS: Considering five different levels for the exposition rate in urban areas and keeping intrarural and urban-rural exposition rates fixed, the preventive measures reduce the size and delay the peak for the urban infectives. The response of infected individuals and cumulative deaths in rural areas upon changes in the urban dynamics was small but not negligible. On the other hand, preventive measures focused on the urban-rural interface impact the number of infected individuals and deaths in rural areas. CONCLUSIONS: The maintenance of SARS-CoV-2 in rural areas depends on the interaction of individuals at the urban-rural interface. Thus, restrictive measures established by the governments would not be required within rural areas. We highlight the importance of focused preventive measures on the urban-rural interface to reduce the exposure and avoid the transmission of SARS-CoV-2 to rural communities.

Quantitative real-time PCR (qPCR) for the detection and quantification of dactylogyrid parasites infecting Lutjanus guttatus.

Severe infections of the spotted rose snapper Lutjanus guttatus resulting from dactylogyrid monogeneans present a risk to aquaculture. Currently, the diagnosis of this infection requires the morphological identification and manual quantification of parasites. Based on the characterization of the 28S rRNA gene of dactylogyrid species present in L. guttatus, specific primers were designed for real-time polymerase chain reaction (qPCR) using EvaGreen® chemistry. The standard curve method estimated the number of dactylogyrids accurately. A total of 85 gill samples from cage-cultured fish infected with dactylogyrids were analysed. The estimated number of dactylogyrids using this molecular method was very similar to the manual count that was performed initially. The standardized qPCR approach will be helpful as a complementary method for the early routine monitoring of dactylogyrid infections and for epidemiological studies in which a high number of fish must be studied.

Helminth parasites of finfish commercial aquaculture in Latin America.

Latin America has tripled production by aquaculture up to 78 million tonnes in the past 20 years. However, one of the problems that aquaculture is facing is the presence of helminth parasites and the diseases caused by them in the region. In this review we have collected all the available information on helminths affecting commercial aquaculture in Latin America and the Caribbean (LAC), emphasizing those causing serious economic losses. Monogeneans are by far the most common and aggressive parasites affecting farmed fish in LAC. They have been recognized as serious pathogens in intensive fish culture because they reach high levels of infection rapidly, and can infect other phylogenetically related fish species. The next most important group comprises the larval stages of digeneans (metacercariae) such as Diplostomum sp. and Centrocestus formosanus, which cause serious damage to farmed fish. Since LAC aquaculture has been based mainly on exotic species (tilapia, salmon, trout and carp), most of their parasites have been brought into the region together with the fish for aquaculture. Recently, one of us (A.I.P.-T.) has suggested that monogeneans, which have generally been considered to be harmless, can produce serious effects on the growth of cultured Nile tilapia. Therefore, the introduction of fish together with their 'harmless' parasites into new sites, regions or countries in LAC should be considered a breakdown of biosecurity in those countries involved. Therefore, the application of quarantine procedures and preventive therapeutic treatments should be considered before allowing these introductions into a country.

Comparison of the anogenital distance and anthropometry of the perineum in patients with and without pelvic organ prolapse. / Comparación de la distancia anogenital y antropometría del periné en pacientes con y sin prolapso de órganos pélvicos.

OBJECTIVES: To determine whether there are differences in the anthropometric measures of the perineum for women with symptomatic pelvic organ prolapse who are candidates for surgery, with or without urinary incontinence, and for patients without pelvic floor dysfunction. The main objective was to measure the anogenital distance in its 2 variants: anoclitoral and anofourchette. The anogenital distance appears to be determined prenatally and is influenced by the intrauterine hormonal environment. The secondary objective was to measure the length of the genital hiatus, the perineal body and the distance between the 2 ischial tuberosities. MATERIAL AND METHODS: An observational case-control study was conducted with 58 patients. The cases (n=22) were patients with stages >II 2 in the Baden-Walker classification system. The controls were patients with normal pelvic floors. Measurements were performed with a digital calliper. The patients' tocogynecological history, lifestyle habits and risk factors were recorded. RESULTS: The case patients had a significantly shorter anogenital anofourchette distance than that of the control patients (P=.001), a significantly longer anogenital anoclitoral distance than the control patients (P=.0001) and a significantly longer genital hiatus length than the control patients (P=.02). CONCLUSIONS: This was an observational study with a small sample. We cannot determine whether the difference in these distances are caused by or are the result of this disease. Given that the anogenital distance appears to be determined prenatally, we question whether this changed distance could be a risk factor for developing pelvic floor dysfunction.

The role of animal reservoirs in social-environmental landscapes: remarks on the control of avian influenza and preparedness for pandemics.

Influenza viruses are well known for their ability to infect and cause disease in a broad range of hosts. Modern advances in reverse genetics have enabled scientists to probe the mutations that allow influenza viruses to perform host switching. Despite this detailed understanding of the molecular modifications that allow host switching and adaptation, there is a gap in knowledge regarding the factors external to the virus and their interactions that act as triggers leading to a pandemic. Studies on the ecology of zoonotic pathogens should be the new paradigm for understanding not only influenza viruses but any other infectious disease that can be a threat to animal and human health. The literature regarding influenza pandemics and influenza virus reservoirs was reviewed to analyse how social and economic changes can influence the appearance of new outbreaks of influenza. In addition, the importance of new research in a dynamic environment driven by the expansion of human territories and animal production systems is highlighted. A new paradigm is proposed for novel research approaches to infectious diseases such as influenza.

Les virus influenza se caractérisent par le large spectre d'hôtes qu'ils sont capables d'infecter et chez lesquels ils provoquent des maladies. Les avancées récentes de la génétique inverse ont permis aux chercheurs de suivre les mutations qui favorisent le passage des virus influenza d'un hôte à l'autre. Bien que les modifications moléculaires à l'origine du passage viral d'une espèce hôte à l'autre et de l'adaptation des virus à de nouveaux hôtes soient désormais bien comprises, d'importantes lacunes subsistent concernant les facteurs extérieurs aux virus et les interactions qui déclenchent la survenue de pandémies. L'étude de l'écologie des agents zoonotiques devrait constituer un nouveau paradigme de la recherche et permettra de mieux comprendre non seulement les virus influenza mais aussi toute maladie infectieuse présentant un danger pour la santé animale et publique. Les auteurs ont étudié la littérature consacrée aux pandémies de grippe et aux réservoirs des virus influenza et analysé l'influence des changements socio-économiques sur la survenue de nouveaux foyers de grippe. Ils soulignent également l'importance de conduire de nouveaux travaux de recherche dans un environnement dynamique transformé par l'extension des territoires utilisés par l'homme ainsi que par les systèmes de production animale. Un nouveau paradigme est ainsi proposé, qui permettra d'élaborer une méthodologie de recherche inédite dans le domaine des maladies infectieuses telles que les grippes.

Es bien conocida la capacidad que tienen los virus de la influenza de infectar y causar enfermedades a un conjunto muy heterogéneo de organismos anfitriones. Valiéndose de los últimos avances de la genética inversa, los científicos han podido utilizar sondas génicas con las mutaciones que permiten a los virus de la influenza pasar de un anfitrión a otro. Pese al detallado conocimiento que se tiene de las modificaciones moleculares que hacen posible el cambio de anfitrión y las correspondientes adaptaciones, no se sabe gran cosa de los factores externos al virus y del modo en que estos factores interaccionan para ejercer de desencadenantes de una pandemia. Los estudios sobre la ecología de patógenos zoonóticos deben ser el nuevo paradigma para comprender no solo los virus de la influenza, sino también los de otras enfermedades infecciosas que puedan constituir una amenaza sanitaria o zoosanitaria. Los autores repasan la bibliografía existente sobre pandemias de influenza y reservorios de este virus con el fin de analizar la repercusión que pueden tener los cambios sociales y económicos en la aparición de nuevos brotes de influenza. Además, se detienen a recalcar la importancia de las nuevas investigaciones en un entorno dinámico, cuya fuerza motriz es la expansión de los territorios humanos y los sistemas de producción animal. Los autores proponen un nuevo paradigma a partir del cual investigar con planteamientos novedosos enfermedades infecciosas como la influenza.

Pregnancy and orthotopic liver transplantation.

BACKGROUND: Sexual and reproductive abnormalities affect up to 50% patients with terminal liver failure. However, these functions recover quickly after orthotopic liver transplantation (OLT). Thus, 80%-90% of OLT women of childbearing age recover menstruation within a few months after transplantation. The aim of our study was to analyze the impact of pregnancy among liver transplant recipients at our center, as well as to analyze the effects of immunosuppression on the fetus. METHODS: From April 1986 to April 2011, we performed 1500 OLT in 1341 recipients. Among these recipients, 18 patients (1.2%) become pregnant during the follow-up. RESULTS: The most frequent causes of terminal liver failure were as follows: chronic parenchymal disease (n = 9; 50%), cholestatic disease (n = 3; 16.6%), acute liver failure (n = 5; 27.7%), and metabolic disease (n = 1; 5.5%) The average recipient age at the beginning of pregnancy was 21.2 (±7.3) years. Sixteen patients (88%) became pregnant beyond a year after OLT. The 30 pregnancies in our study resulted in the following: newborns alive (NBA; n = 20; 66.6%) abortions (n = 8; 26.6%) or fetal deaths (n = 2; 6%). The most common immunosuppressant used during pregnancy was tacrolimus (75%) followed by cyclosporine (25%). There were no maternal deaths during pregnancy or the postpartum period. DISCUSSION: We did not observe significant differences between immunosuppression type and maternal complications, pregnancy duration, and childbirth type. Although pregnancy is potential risk, the literature and our results suggest that at a year or more after OLT it usually is safe and successful.

Obstructive jaundice due to hepatocarcinoma with intraductal growth. Report of a successful resection.

We present a patient with hepatocellular carcinoma causing obstructive jaundice due to intraductal growth, diagnosed intraoperatively by cholangiography and histological examination, and radically treated by left lobectomy, extrahepatic biliary tract resection and Roux-en-Y hepaticojejunostomy. Survival after operation was 13 months. Other similar cases reported in the literature are reviewed.

Acetylator polymorphism in discoid lupus erythematosus.

Acetylator phenotype was determined, using sulphamethazine, in 37 patients with histologically confirmed discoid lupus erythematosus, who were free from visceral damage, and in 157 normal control subjects. Twenty patients (54%) and 90 control subjects (57.4%) were slow acetylators (p not significant). Acetylator polymorphism appears not to be related to the risk of developing pure cutaneous discoid lupus erythematosus.

Biometria fetal por ultrasonidos. / Ultrasonic fetal biometry

A nuestro universo de 1.551 exploraciones ecograficas, aplicamos diferentes curvas de regresion por trimestre y por sexo del feto para encontrar la mejor ecuacion que exprese el crecimiento del D.B.P. en funcion de la edad gestacional. A lo largo de estos ensayos se pudo establecer las diferencias de crecimiento entre el segundo y tercer trimestre; escogiendose como la mejor curva la de tipo logistico por describir mejor dichas diferencias y presentar el mejor coeficiente