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1.
Rev. Soc. Bras. Med. Trop ; Rev. Soc. Bras. Med. Trop;57: e00700, 2024. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1535381

ABSTRACT

ABSTRACT Background: We assessed the distribution of triatomines in an endemic area for Chagas disease. Methods: This retrospective study used secondary data extracted from the Official System of the National Chagas Disease Control Program (Sistema Oficial do Programa Nacional de Controle da Doença de Chagas - SisPCDCh). Results: A total of 7,257 (725.7 ± 221.7 per year) specimens were collected from 2013 to 2022. Most of them (6,792; 93.6%) were collected in the intradomicile and 465 (6.4%) in the peridomicile. A total of 513 (7.1%) triatomines tested positive for the presence of trypomastigote forms, similar to Trypanosoma cruzi. Conclusions: The spatial analysis revealed a heterogeneous distribution of triatomines across different municipalities.

2.
Exp Appl Acarol ; 91(2): 339-358, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37768388

ABSTRACT

We report Rickettsia species from 2,334 ticks collected from environment (1,939 ticks) and animals (395 ticks) in the largest inland fragment of the Atlantic rainforest of southern Brazil and its fragments. Additionally, the DNA infection rates of Amblyomma ovale tick populations in the Neotropics with Rickettsia bellii and Rickettsia parkeri strain Atlantic rainforest were calculated using data from scientific publications, and their correlation was evaluated. From 11 tick species Rickettsia DNA was detected in seven (Amblyomma brasiliense, Amblyomma coelebs, Amblyomma incisum, Amblyomma longirostre, A. ovale, Haemaphysalis juxtakochi, Ixodes fuscipes) and was not detected in four species (Amblyomma dubitatum, Ixodes loricatus, Rhipicephalus microplus and Rhipicephalus sanguineus sensu lato). DNA of five Rickettsia species was detected (R. bellii, Rickettsia amblyommatis, Rickettsia rhipicephali, Rickettsia felis and Rickettsia sp. Aragaoi). To determine the prevalence of Rickettsia DNA positivity according to vector species, ticks were processed individually or in pools of 2-10 individuals (samples). The most prevalent Rickettsia species was R. bellii, found in 112 samples, followed by R. amblyommatis, R. rhipicephali, R. felis and Rickettsia sp. Aragaoi, found in 16, five, two and one sample, respectively. Rickettsia bellii DNA was found in five tick species with the highest infection rate in A. ovale and A. brasiliense. Absence of R. parkeri strain Atlantic rainforest in A. ovale ticks was an unexpected result. Furthermore, a negative correlation was identified between the infection rates (DNA) of R. bellii and/or R. parkeri strain Atlantic rainforest within A. ovale tick populations in the Neotropics. Putting together current knowledge, it can be proposed that, within natural settings, the diversity of rickettsiae and ticks creates a buffering effect on the overgrowth of rickettsiae and episodes of bacteremia in the hosts.

3.
São Paulo med. j ; São Paulo med. j;141(2): 120-124, Mar.-Apr. 2023. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1424670

ABSTRACT

ABSTRACT BACKGROUND: Since the impact of the coronavirus disease 2019 (COVID-19) pandemic in March 2020, several studies have shown a strong relationship between obesity and severe cases of COVID-19. It is imperative to assess whether bariatric surgery exerts a protective effect in such cases. OBJECTIVE: This study aimed to assess the impact of bariatric surgery on the morbidity and mortality in obese patients during the COVID-19 pandemic. A comprehensive search was performed using the PubMed and Cochrane Library databases. DESIGN AND SETTING: Retrospective cohort studies conducted in the Faculdade de Medicina da Universidade Cidade de São Paulo, São Paulo (SP), Brazil. METHODS: The search comprised the following descriptors: "bariatric, surgery, COVID-19". Current retrospective cohort studies that examined the influence of bariatric surgery on the morbidity and mortality of obese patients during the COVID-19 pandemic were considered eligible. RESULTS: After removing duplicates, 184 studies were obtained from the databases. Of these, 181 were excluded from the analysis as they did not meet the eligibility criteria. Patients undergoing postoperative follow-up of bariatric surgery had a similar probability of SARS-CoV-2 infection compared to the general population, and persistent comorbidities were associated with an increased risk and severity of infection. CONCLUSION: Bariatric surgery has a protective effect against severe COVID-19 in the obese population, bringing the prevalence of severe disease cases to levels equivalent to those of the nonobese general population, with a positive impact on morbidity and mortality.

4.
Front Public Health ; 11: 1117680, 2023.
Article in English | MEDLINE | ID: mdl-36969625

ABSTRACT

Background: An automated hand-hygiene monitoring system (AHHMS) was implemented in October 2019 at the Hospital Infantil de México Federico Gómez (HIMFG), a tertiary pediatric referral hospital, in four of the hospital wards with the highest rates of Healthcare Associated Infections (HAIs). The clinical and economic impact of this system had not yet been assessed prior to this study. This study aimed to evaluate if the AHHMS is a cost-effective alternative in reducing HAIs in the HIMFG. Methodology: A full cost-effectiveness economic assessment was carried out for the hospital. The alternatives assessed were AHHMS implementation vis-a-vis AHHMS non-implementation (historical tendency). The outcomes of interest were infection rate per 1,000 patient-days and cost savings as a result of prevented infections. Infection rate data per 1,000 patient-days (PD) were obtained from the hospital's Department of Epidemiology with respect to the AHHMS. As regards historical tendency, an infection-rate model was designed for the most recent 6-year period. Infection costs were obtained from a review of available literature on the subject, and the cost of the implemented AHHMS was provided by the hospital. The assessment period was 6 months. The incremental cost-effectiveness ratio was estimated. Costs are reported in US Dollars (2021). Univariate sensitivity and threshold analysis for different parameters was conducted. Results: The total estimated cost of the AHHMS alternative represented potential savings of $308,927-$546,795 US Dollars compared to non-implementation of the system (US$464,102 v. US$773,029-$1,010,898) for the period. AHHMS effectiveness was reflected in a diminished number of infections, 46-79 (-43.4-56.7%) compared to non-implementation (60 v. 106-139 infections). Conclusion: The AHHMS was found to be a cost-saving alternative for the HIMFG given its cost-effectiveness and lower cost vis-a-vis the alternate option. Accordingly, the recommendation was made of extending its use to other areas in the hospital.


Subject(s)
Cross Infection , Hand Hygiene , Humans , Child , Cost-Effectiveness Analysis , Mexico , Hospitals, Pediatric , Cross Infection/prevention & control
5.
Viruses ; 15(3)2023 03 17.
Article in English | MEDLINE | ID: mdl-36992479

ABSTRACT

Zika virus (ZIKV) is transmitted to humans by the infectious bite of mosquitoes such as Aedes aegypti. In a city, the population control of mosquitoes is carried out according to alerts generated by different districts via the analysis of the mosquito index. However, we do not know whether, besides mosquito abundance, the susceptibility of mosquitoes could also diverge among districts and thus impact the dissemination and transmission of arboviruses. After a viremic blood meal, the virus must infect the midgut, disseminate to tissues, and reach the salivary gland to be transmitted to a vertebrate host. This study evaluated the patterns of ZIKV infection in the Ae. aegypti field populations of a city. The disseminated infection rate, viral transmission rate, and transmission efficiency were measured using quantitative PCR at 14 days post-infection. The results showed that all Ae. aegypti populations had individuals susceptible to ZIKV infection and able to transmit the virus. The infection parameters showed that the geographical area of origin of the Ae. aegypti influences its vector competence for ZIKV transmission.


Subject(s)
Aedes , Zika Virus Infection , Zika Virus , Animals , Humans , Zika Virus/genetics , Brazil/epidemiology , Saliva , Mosquito Vectors
6.
Diagnostics (Basel) ; 12(11)2022 Nov 01.
Article in English | MEDLINE | ID: mdl-36359496

ABSTRACT

Visceral leishmaniasis remains a serious public health issue, and Brazil was among the seven countries with the highest prevalence of this disease worldwide. The measures to control this disease are not easily developed, and the improvement of its diagnosis, surveillance, and control is still needed. This study aimed to carry out the polymerase chain reaction (PCR) diagnosis of Leishmania infantum in vector samples in some municipalities of the State of São Paulo, which included two municipalities with human disease transmission and two with dog transmission only. Vectors were collected in traps with luminous bait. Next, they were killed at -4 °C and kept in 70% alcohol. Groups of ten female insects (pools) were mashed on cation exchange paper (fine cellulose phosphate with 18 µEq/cm² ionic exchange capacity) for DNA extraction. The PCR was carried out to identify the natural infection of the Leishmania genus in female Lutzomyia longipalpis (Lu. Longipalpis). Out of the 3,880 Lu. longipalpis phlebotomines, 1060 were female and 2820 were male (3:1). The method used to extract the DNA in pools of ten phlebotomines and the PCR resulted in sensitivity, specificity, practicality, and faster analyses when compared to the individual analysis method. The procedure described can be used on a large scale in the leishmaniasis epidemiological surveillance, enabling a higher number of analyses and the optimization of human resources because the traditional diagnostic method is carried out via desiccation of the insect digestive system and microscopic examination, which is time-demanding and there is the need of manual skills.

7.
J Math Biol ; 85(4): 32, 2022 09 17.
Article in English | MEDLINE | ID: mdl-36114922

ABSTRACT

The SIR (susceptible-infectious-recovered) model is a well known method for predicting the number of people (or animals) in a population who become infected by and then recover from a disease. Modifications can include categories such people who have been exposed to the disease but are not yet infectious or those who die from the disease. However, the model has nearly always been applied to the entire population of a country or state but there is considerable observational evidence that diseases can spread at different rates in densely populated urban regions and sparsely populated rural areas. This work presents a new approach that applies a SIR type model to a country or state that has been divided into a number of geographical regions, and uses different infection rates in each region which depend on the population density in that region. Further, the model contains a simple matrix based method for simulating the movement of people between different regions. The model is applied to the spread of disease in the United Kingdom and the state of Rio Grande do Sul in Brazil.


Subject(s)
Models, Theoretical , Animals , Brazil/epidemiology , Humans , Population Density , United Kingdom
8.
Zoonoses Public Health ; 69(2): 95-105, 2022 03.
Article in English | MEDLINE | ID: mdl-34713588

ABSTRACT

This research analysed the spatiotemporal distribution of triatomines infected by trypanosomatid parasites in an endemic region for Chagas disease, in the state of Pernambuco, Northeastern Brazil. The database included the total number of triatomines captured from intradomicile and peridomicile areas, as well as the infection rate (IR) by trypanosomatid. The Gi∗ by Getis-Ord method was used to statistically identify significant concentration clusters and the IR of triatomines by trypanosomatids. A generalized linear regression model with a binomial distribution was used to evaluate the probability of finding an IR by trypanosomatids. Overall, of 4,800 triatomines examined, trypanosomatid forms similar to Trypanosoma cruzi were detected in 10.29% of them, and the majority of positive specimens (98.17%) were collected at intradomicile. The geospatial analyses identified triatomines clusters in intradomicile and peridomicile environments. According to the logistic regression data for species (Panstrongylus lutzi, P. megistus, Triatoma brasiliensis and T. pseudomaculata), the probability of detection of T. cruzi infection remains constant in up to 50 specimens examined or more. The findings of this research revealed a scenario never studied in this area through this type of spatiotemporal analysis, which is essential to identify areas of vulnerability for the occurrence of these vectors and consequently for Chagas disease.


Subject(s)
Chagas Disease , Kinetoplastida , Triatominae , Trypanosoma cruzi , Trypanosomatina , Animals , Brazil/epidemiology , Chagas Disease/epidemiology , Chagas Disease/veterinary , Insect Vectors/parasitology
9.
Bol. malariol. salud ambient ; 62(4): 873-878, 2022. tab
Article in Spanish | LILACS, LIVECS | ID: biblio-1416645

ABSTRACT

Musca domestica (Diptera, Muscidae) es la mosca más común en todo el mundo. Más de 100 patógenos pueden causar enfermedades en humanos y animales por este tipo de insectos. Estos patógenos incluyen: diarrea infantil, ántrax, cólera, oftalmía, disentería bacilar, fiebre tifoidea y tuberculosis. Además, las moscas domésticas transmiten muchos de los huevos de helmintos como Enterobius vermicularis, Strongyloides stercoralis, Trichuris trichiura, Toxocara canis, y especies de Dipylidium, Diphyllobothriam, Hymenolepis, Taenia y Trichomonas. También puede transmitir quistes de protozoos y trofozoítos como E. histolytica y Giardia lamblia. Se determinó el índice de infestación por Musca domestica L. (Díptera, Muscidae) en una faenadora avícola ubicada en el Perú. Para ello se evaluó no sólo el tratamiento aplicado: protocolo de cola entomológica (T1), monitoreo de insfectación de mosca (T2) o comincación de lámparas LED UV más tabla de pegamento adhesivo (T3), sino también las diferentes zonas de faenadora: zonas sucias de descarga y estabulación (ZDE), preparación (ZP), zonas adicionales de sacrificio sanitario (ZSS), preparación de residuos orgánicos (ZPRO), conservación de los residuos orgánicos (ZCRO) y de conservación de sangre (ZCS). Los resultados demoestraron que, independientemente de la zona de operación, el tratamiento más efectivo para determinar la infestación por la mosca doméstica fue el combinado de lámpara LED junto con tablas de pegamento (T3), seguido del tratamiento de protocolo de cola entomológica (T1) y el tratamiento por Monitoreo de infestación de moscas (T2) independientemente de los días de recolección. Es importante seguir las diferentes normativas a fin de controlar y eliminar la presencia de moscas (y de otros insectos voladores) para evitar la contaminación y, por ende, enfermedades(AU)


Musca domestica (Diptera, Muscidae) is the most common fly in the world. More than 100 pathogens can cause diseases in humans and animals by these types of insects. These pathogens include: infant diarrhea, anthrax, cholera, ophthalmia, bacillary dysentery, typhoid fever, and tuberculosis. In addition, houseflies transmit many of the eggs of helminths such as Enterobius vermicularis, Strongyloides stercoralis, Trichuris trichiura, Toxocara canis, and Dipylidium, Diphyllobothriam, Hymenolepis, Taenia, and Trichomonas species. It can also transmit cysts of protozoa and trophozoites such as E. histolytica and Giardia lamblia. The infestation index by Musca domestica L. (Diptera, Muscidae) was determined in a poultry slaughterhouse located in Peru. For this, not only the applied treatment was evaluated: entomological glue protocol (T1), fly infestation monitoring (T2) or combination of UV LED lamps plus adhesive glue table (T3), but also the different slaughter areas: unloading and holding areas (ZDE), preparation (ZP), additional stamping-out areas (ZSS), preparation of organic waste (ZPRO), conservation of organic waste (ZCRO) and blood conservation (ZCS). The results showed that, regardless of the area of operation, the most effective treatment to determine housefly infestation was the LED lamp combined with glue boards (T3), followed by the entomological glue protocol treatment (T1 ) and the treatment by Monitoring of fly infestation (T2) regardless of the days of collection. It is important to follow the different regulations in order to control and eliminate the presence of flies (and other flying insects) to avoid contamination and, therefore, diseases(AU)


Subject(s)
Animals , Poultry , Diptera , Houseflies , Insecta , Food Contamination , Cholera , Diarrhea, Infantile , Dysentery, Bacillary , Eggs
10.
Insects ; 12(11)2021 Oct 26.
Article in English | MEDLINE | ID: mdl-34821768

ABSTRACT

Aedes (Stegomyia) albopictus is a mosquito native to Southeast Asia. Currently, it has a wide distribution in America, where natural infection with arboviruses of medical and veterinary importance has been reported. In spite of their importance in the transmission of endemic arbovirus, the basic information of parameters affecting their vectorial capacity is poorly investigated. The aim of the work was to update the distribution range of Ae. albopictus in the Americas, review the blood-feeding patterns, and compare the minimum infection rate (MIR) of the Dengue virus (DENV) between studies of vertical and horizontal transmission. The current distribution of Ae. albopictus encompasses 21 countries in the Americas. An extensive review has been conducted for the blood-feeding patterns of Ae. albopictus. The results suggest that the mosquito is capable of feeding on 16 species of mammals and five species of avian. Humans, dogs, and rats are the most common hosts. Eight arboviruses with the potential to infect humans and animals have been isolated in Ae. albopictus. In the United States of America (USA), Eastern equine encephalitis virus, Keystone virus, La Crosse Virus, West Nile virus, and Cache Valley virus were isolated in the Asian mosquito. In Brazil, Mexico, Colombia, and Costa Rica, DENV (all serotypes) has been frequently identified in field-caught Ae. albopictus. Overall, the estimated MIR in Ae. albopictus infected with DENV is similar between horizontal (10.95) and vertical transmission (8.28). However, in vertical transmission, there is a difference in the MIR values if the DENV is identified from larvae or adults (males and females emerged from a collection of eggs or larvae). MIR estimated from larvae is 14.04 and MIR estimated in adults is 4.04. In conclusion, it has to be highlighted that Ae. albopictus is an invasive mosquito with wide phenotypic plasticity to adapt to broad and new areas, it is highly efficient to transmit the DENV horizontally and vertically, it can participate in the inter-endemic transmission of the dengue disease, and it can spread zoonotic arboviruses across forest and urban settings.

11.
Article in English | MEDLINE | ID: mdl-34299942

ABSTRACT

Although vaccination is carried out worldwide, the vaccination rate varies greatly. As of 24 May 2021, in some countries, the proportion of the population fully vaccinated against COVID-19 has exceeded 50%, but in many countries, this proportion is still very low, less than 1%. This article aims to explore the impact of vaccination on the spread of the COVID-19 pandemic. As the herd immunity of almost all countries in the world has not been reached, several countries were selected as sample cases by employing the following criteria: more than 60 vaccine doses per 100 people and a population of more than one million people. In the end, a total of eight countries/regions were selected, including Israel, the UAE, Chile, the United Kingdom, the United States, Hungary, and Qatar. The results find that vaccination has a major impact on reducing infection rates in all countries. However, the infection rate after vaccination showed two trends. One is an inverted U-shaped trend, and the other is an L-shaped trend. For those countries with an inverted U-shaped trend, the infection rate begins to decline when the vaccination rate reaches 1.46-50.91 doses per 100 people.


Subject(s)
COVID-19 , Immunity, Herd , Chile/epidemiology , Humans , Hungary , Israel/epidemiology , Pandemics , Qatar , SARS-CoV-2 , United Kingdom , Vaccination
12.
Viruses ; 14(1)2021 12 23.
Article in English | MEDLINE | ID: mdl-35062224

ABSTRACT

The successful spread and maintenance of the dengue virus (DENV) in mosquito vectors depends on their viral infection susceptibility, and parameters related to vector competence are the most valuable for measuring the risk of viral transmission by mosquitoes. These parameters may vary according to the viral serotype in circulation and in accordance with the geographic origin of the mosquito population that is being assessed. In this study, we investigated the effect of DENV serotypes (1-4) with regards to the infection susceptibility of five Brazilian Ae. aegypti populations from Manaus, the capital of the state of Amazonas, Brazil. Mosquitoes were challenged by oral infection with the DENV serotypes and then tested for the presence of the arbovirus using quantitative PCR at 14 days post-infection, which is the time point that corresponds to the extrinsic incubation period of Ae. aegypti when reared at 28 °C. Thus, we were able to determine the infection patterns for DENV-1, -2, -3 and -4 in the mosquito populations. The mosquitoes had both interpopulation and inter-serotype variation in their viral susceptibilities. All DENV serotypes showed a similar tendency to accumulate in the body in a greater amount than in the head/salivary gland (head/SG), which does not occur with other flaviviruses. For DENV-1, DENV-3, and DENV-4, the body viral load varied among populations, but the head/SG viral loads were similar. Differently for DENV-2, both body and head/SG viral loads varied among populations. As the lack of phenotypic homogeneity represents one of the most important reasons for the long-term fight against dengue incidence, we expect that this study will help us to understand the dynamics of the infection patterns that are triggered by the distinct serotypes of DENV in mosquitoes.


Subject(s)
Aedes/virology , Dengue Virus/physiology , Mosquito Vectors/virology , Animals , Brazil , Dengue Virus/genetics , Female , Serogroup , Viral Load
13.
Environ Sci Pollut Res Int ; 28(30): 40322-40328, 2021 Aug.
Article in English | MEDLINE | ID: mdl-32989697

ABSTRACT

The new coronavirus SARS-CoV-2 has infected more than 14 million people worldwide so far. Brazil is currently the second leading country in number of cases of COVID-19, while São Paulo state accounts for 20% of total confirmed cases in Brazil. The aim of this study was to assess environmental and social factors influencing the spread of SARS-CoV-2 in the expanded metropolitan area of São Paulo, Brazil. Firstly, a spatial analysis was conducted to provide insights into the spread of COVID-19 within the expanded metropolitan area. Moreover, Spearman correlation test and sensitivity analysis were performed to assess social indicators and environmental conditions which possibly influence the incidence of COVID-19. Our results reveal that the spread of COVID-19 from the capital city São Paulo-its epicenter in Brazil-is directly associated with the availability of highways within the expanded metropolitan area of São Paulo. As for social aspects, COVID-19 infection rate was found to be both positively correlated with population density, and negatively correlated with social isolation rate, hence indicating that social distancing has been effective in reducing the COVID-19 transmission. Finally, COVID-19 infection rate was found to be inversely correlated with both temperature and UV radiation. Together with recent literature our study suggests that the UV radiation provided by sunlight might contribute to depletion of SARS-CoV-2 infectivity.


Subject(s)
COVID-19 , Pandemics , Brazil/epidemiology , Humans , SARS-CoV-2 , Social Factors
14.
JMIR Res Protoc ; 9(12): e24357, 2020 Dec 15.
Article in English | MEDLINE | ID: mdl-33156812

ABSTRACT

BACKGROUND: Patients with immune-mediated rheumatic diseases (IMRD) are at increased risk of infections, including significant morbidity and high mortality. Considering the potential for unfavorable outcomes of SARS-CoV-2 infection in patients with IMRD, several questions were raised regarding the impact of COVID-19 at the start of the pandemic. OBJECTIVE: This paper presents the protocol of a study that aims to prospectively evaluate patients with IMRD and a confirmed COVID-19 diagnosis (using criteria provided by the Brazilian Ministry of Health). METHODS: The study comprised a prospective, observational cohort (patients with IMRD and COVID-19) and a comparison group (patients with only IMRD), with a follow-up time of 6 months to evaluate differences in health outcomes. The primary outcomes will be changes in IMRD disease activity after SARS-CoV-2 infection at 4 time points: (1) at baseline, (2) within 4-6 weeks after infection, (3) at 3 months after the second assessment (±15 days), and (4) at 6 months (±15 days). The secondary outcomes will be the progression rate to moderate or severe forms of COVID-19, need for intensive care unit admission and mechanical ventilation, death, and therapeutic changes related to IMRD. Two outcomes-pulmonary and thromboembolic events in patients with both IMRD and SARS-CoV-2 infection-are of particular interest and will be monitored with close attention (clinical, laboratory, and function tests as well as imaging). RESULTS: Recruitment opened in May 2020, with 1300 participants recruited from 43 sites as of November 2020. Patient recruitment will conclude by the end of December 2020, with follow-up occurring until April 2021. Data analysis is scheduled to start after all inclusion data have been collected, with an aim to publish a peer-reviewed paper in December 2020. CONCLUSIONS: We believe this study will provide clinically relevant data on the general impact of COVID-19 on patients with IMRD. TRIAL REGISTRATION: Brazilian Registry of Clinical Trials RBR-33YTQC; http://www.ensaiosclinicos.gov.br/rg/RBR-33ytqc/. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/24357.

15.
Chaos Solitons Fractals ; 139: 110297, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32982083

ABSTRACT

This work introduces a new markovian stochastic model that can be described as a non-homogeneous Pure Birth process. We propose a functional form of birth rate that depends on the number of individuals in the population and on the elapsed time, allowing us to model a contagion effect. Thus, we model the early stages of an epidemic. The number of individuals then becomes the infectious cases and the birth rate becomes the incidence rate. We obtain this way a process that depends on two competitive phenomena, infection and immunization. Variations in those rates allow us to monitor how effective the actions taken by government and health organizations are. From our model, three useful indicators for the epidemic evolution over time are obtained: the immunization rate, the infection/immunization ratio and the mean time between infections (MTBI). The proposed model allows either positive or negative concavities for the mean value curve, provided the infection/immunization ratio is either greater or less than one. We apply this model to the present SARS-CoV-2 pandemic still in its early growth stage in Latin American countries. As it is shown, the model accomplishes a good fit for the real number of both positive cases and deaths. We analyze the evolution of the three indicators for several countries and perform a comparative study between them. Important conclusions are obtained from this analysis.

16.
Plant Dis ; 104(4): 1013-1018, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32065564

ABSTRACT

The El Niño Southern Oscillation (ENSO) is an oceanic-atmospheric phenomenon influencing worldwide weather and climate. Its occurrence is determined by the sea surface temperature (SST) anomaly of the 3.4 Niño region in the Pacific Ocean (5°N-5°S, 120°-170°W). El Niño (EN), Neutral (NT), and La Niña (LN) are the three possible phases of ENSO, respectively, for warm, normal, and cold SST anomaly. As in other regions around the world, weather in Brazil is influenced by ENSO phases. The country is the major coffee producer in the world, and production is strongly influenced by weather conditions, which affect plant yield, harvest quality, and interactions with pests and diseases. Coffee leaf rust (CLR), caused by the fungus Hemileia vastatrix, is a major cause of coffee yield and quality losses in Brazil, and requires fungicide spray applications every season. Because CLR is highly influenced by weather conditions, it is possible to use weather variables to simulate its progress during the cropping cycle. Therefore, the aims of this study were to estimate CLR infection rate based on a validated empirical model, which has daily minimum air temperature and relative humidity as inputs, and to assess the extent of ENSO influence on the annual risk of this disease at 45 sites in Brazil. Cumulative infection rates (CIR) were estimated daily from October to June of each growing season and location, based on the prevailing ENSO phase. Differences between the extreme phases (EN-LN) were assessed by the Two-One-Sided-Tests (TOST) method. Analysis of data from eight sites, located mainly in Paraná State, provided evidence of CIR differences between EN and LN phases (G1). Evidence of no difference of CIR between EN and LN was found in 18 sites (G2), whereas 19 sites showed no evidence of differences (G3) due to relatively large variation of CIR within the same ENSO phase. The G1 sites are located mostly in Southern Brazil, where ENSO exerts a well-defined influence on rainfall regime. In contrast, the G2 sites are mainly in Minas Gerais State, which is characterized as a transition region for ENSO influence on rainfall. The G3 sites are located between the northern region of Minas Gerais State and southern region of Bahia State, which is characterized by a subhumid climate that is usually very dry during winter, and where rainfall can vary up to 300% from one year to another, influencing relative humidity and resulting in a high CIR variability. Therefore, ENSO had a well-defined influence on CIR only in Paraná State, a region with minor importance for coffee production in Brazil. No ENSO influence was found in more northerly zones where the majority of Brazilian coffee is produced. This is the first evidence of ENSO-linked regional impact on the risk of coffee rust.


Subject(s)
Coffee , El Nino-Southern Oscillation , Brazil , Seasons , Weather
17.
Rev. Soc. Bras. Med. Trop ; Rev. Soc. Bras. Med. Trop;51(2): 174-182, Mar.-Apr. 2018. tab, graf
Article in English | LILACS | ID: biblio-897071

ABSTRACT

Abstract INTRODUCTION: Chagas disease remains a public health problem in the rural and urban areas of 19 countries in the Americas. METHODS: The aim of the present study was to investigate the Trypanosoma cruzi infection rate of triatomines collected from both intra- and peridomiciliary areas in eleven municipalities of Southeastern Ceará, Brazil, from 2009 to 2015. RESULTS: A total of 32,364 triatomine specimens, including nymphs and adults, were collected, and 31,736 (98.06%) of these were examined. More nymphs were collected than adults, and the greatest number of triatomines (n = 8,548) was collected in 2010, for which the infection rate was 1.3%, with the highest rate of infections observed for specimens from Quixere. The species collected during the study were identified as Triatoma pseudomaculata, Triatoma brasiliensis, Panstrongylus megistus, Panstrongylus lutzi, and Rhodnius nasutus, with T. pseudomaculata being the most abundant (n = 19,962). CONCLUSIONS: These results verify the presence of triatomines in both intra- and peridomiciliary areas, thereby ensuring persistence of the pathogen and consequently, the disease, as the presence of infected vectors in households is an important risk factor. According to these findings, the Chagas Disease Control Program should intensify its efforts in order to prevent the spread of the disease.


Subject(s)
Animals , Panstrongylus/parasitology , Rhodnius/parasitology , Triatoma/parasitology , Insect Vectors/classification , Brazil , Retrospective Studies , Population Density , Chagas Disease/transmission , Insect Vectors/parasitology
18.
Acta Trop ; 181: 1-5, 2018 May.
Article in English | MEDLINE | ID: mdl-29373820

ABSTRACT

This study identified the natural infection rate of Leishmania (Leishmania) infantum in Lutzomyia longipalpis sandflies collected in a neighborhood around a kennel, in Dracena, northwestern of São Paulo state. This region is highly endemic for visceral leishmaniasis in Brazil. Insects were captured during 2-3 nights monthly for 11 months (January-November 2012) using 10 automatic light traps around a kennel in a transition between periurban and urban neighborhood. Capture aimed the determination of the minimal infection rate (MIR) on the area. A total of 1690 Lu. longipalpis were captured during the studied period. Out of them, 292 (17.25%) were females and were grouped in 165 pools containing 1 to five insects for DNA extraction and PCR analysis. Positive results for L. (L) infantum in conventional PCR and real time PCR were shown in 7.28% (12/165) and 4.85% (8/165) of the analysis respectively. These data confirm that Lu. longipalpis captured in the study area were infected by L. (L.) infantum. The MIR of sandflies during the 11 months of captures was 4.10% for female the total of 292 female sandflies collected. A high DNA concentration of L. (L.) infantum was detected on sandflies especially in kennel, chicken coop and neighboring houses, where higher abundance of hosts for blood source were present.


Subject(s)
Insect Vectors/parasitology , Leishmania infantum/isolation & purification , Leishmaniasis, Visceral/transmission , Psychodidae/parasitology , Animals , Brazil/epidemiology , Female , Humans , Leishmania infantum/genetics , Leishmaniasis, Visceral/epidemiology , Male , Polymerase Chain Reaction
19.
Clinics ; Clinics;73: e182, 2018. tab
Article in English | LILACS | ID: biblio-952799

ABSTRACT

OBJECTIVES: To compare the results respectively obtained from the utilization of 60% barium sulfate suspension and Iohexol as contrast agents for videofluoroscopic swallowing studies and the relationship between the clinical application of the two kinds of contrast agents and the incidence of pneumonia. METHODS: Sixty cases of stroke patients with dysphagia were selected in rehabilitation department of our hospital, and the gender, age, position of the disease, and stroke nature between groups had no significant difference. Among which, 30 patients who were administered 350 mgI/ml Iohexol, and the other 30 patients with 60% barium sulfate suspension as contrast agent. We performed videofluoroscopic swallowing studies with barium 60% versus Iohexol within 1 week after admission and 2 weeks after admission. RESULTS: After 2 weeks in hospital, the aspiration pneumonia incidence of two groups was statistically significant (p<0.05), the pneumonia incidence of Iohexol group was lower than barium sulfate group which might have a impossble relevance with barium aspiration. CONCLUSIONS: During the videofluoroscopic swallowing study of dysphagia after stroke, barium sulfate can enhance the pneumonia incidence, and Iohexol can be widely applied in videofluoroscopic swallowing study.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , Pneumonia, Aspiration/chemically induced , Barium Sulfate/adverse effects , Fluoroscopy/methods , Deglutition Disorders/diagnostic imaging , Contrast Media/adverse effects , Pneumonia, Aspiration/diagnosis , Barium Sulfate/administration & dosage , Video Recording/methods , Iohexol/administration & dosage , Iohexol/adverse effects , Deglutition Disorders/complications , Contrast Media/administration & dosage , Deglutition/drug effects , Stroke Rehabilitation/methods
20.
Parasite Immunol ; 39(12)2017 Dec.
Article in English | MEDLINE | ID: mdl-28929503

ABSTRACT

We aimed to induce and inhibit HO-1, ascertaining its effect on infection rate, parasite load and the levels of superoxide, reactive oxygen species (ROS), nitric oxide (NO), TNF-alpha and IL-10 in cultured macrophages from healthy dogs infected by Leishmania infantum. Macrophages obtained from 15 healthy dogs were cultured alone or infected with L. infantum, with or without association of HO-1 inducer and inhibitor. The infection rate and the parasite load were determined by the number of infected macrophages and number of promastigotes per macrophage, respectively. HO-1 levels and gene expression, as well as IL-10 and TNF-alpha levels were also measured in these cultures. Superoxide, ROS and NO levels in macrophages were measured through flow cytometry. Induction of HO-1 increased the infection rate and parasite load, while its inhibition decreased the infection rate and IL-10 production. There was a positive correlation between HO-1 and infection rate or parasite load. Increased infection rate was associated with decreased superoxide, ROS and NO levels. Induction of HO-1 metabolism in dogs infected by L. infantum is possibly one of the mechanisms responsible for increasing the infection of macrophages, mainly through reduction in the oxidative and nitrosative metabolisms of these cells.


Subject(s)
Heme Oxygenase-1/metabolism , Leishmania infantum/physiology , Leishmaniasis, Visceral/veterinary , Macrophages/parasitology , Parasite Load , Animals , Cells, Cultured , Dog Diseases/parasitology , Dogs , Gene Expression , Heme Oxygenase-1/antagonists & inhibitors , Interleukin-10/genetics , Interleukin-10/metabolism , Nitric Oxide/metabolism , Superoxides/metabolism , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/metabolism
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