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1.
Sci Total Environ ; 942: 173805, 2024 Sep 10.
Article in English | MEDLINE | ID: mdl-38848917

ABSTRACT

BACKGROUND: Seagrass meadows are among the most abundant marine coastal ecosystems in the world. The wide variety of species, a worldwide distribution with overall high abundance, and especially their high productivity make them a plausible nature-based blue carbon solution to mitigate atmospheric CO2 levels. In the Mediterranean Basin, the endemic angiosperm Posidonia oceanica plays a remarkable role as a marine habitat provider in shallow waters through its vertical growth and as a carbon sink storing allochthonous carbon and biomass underneath the meadows. OBJECTIVES: Here, we assess the capacity of a pristine meadow to oxygenate the water column in the coastal area of the Balearic Islands through an evaluation of the metabolic rates in the benthic compartment as well as the resulting oxygen concentrations in the pelagic compartment. METHODS: Gross primary production (GPP), respiration (R), and net community production (NCP) are determined from dissolved oxygen (DO) measurements using two different calculation methods: a model developed for this purpose is used for data obtained from water column sensors and benthic multiparametric sensors, whereas the mass balance of measured DO is used to calculate the metabolic rates inside benthic chambers. RESULTS: The meadow at our study site was characterised as a net autotrophic ecosystem throughout the year. Oxygen productivity was significantly higher in the benthic compartment than in the water column and followed clear seasonal patterns, with enhanced productivity during spring. NOVELTY: This work shows the key role of a healthy Posidonia oceanica ecosystem as a water column oxygenator by comparing primary production using three different sampling strategies. The potential of the seagrass as climate change mitigator and its importance for the Mediterranean coasts should be considered in future coastal planning strategies.


Subject(s)
Alismatales , Oxygen , Oxygen/analysis , Oxygen/metabolism , Ecosystem , Spain , Environmental Monitoring , Biomass , Seawater/chemistry
2.
Exp Appl Acarol ; 90(3-4): 441-453, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37498401

ABSTRACT

Rickettsia species are bacteria that may cause multiple diseases in animals and humans, via transmission through multiple arthropod vectors. Routine surveillance of Rickettsia spp. within vectors is critical to determine their presence and risk to mammalian hosts within human populations. Therefore, to better characterize the circulating Rickettsia species in an understudied region we targeted pet dogs to survey. Ticks were collected from pet dogs in three populations of the Yucatan where we tested for the presence of Rickettsia spp. by PCR in metagenomic DNA. In these ticks removed from pet dogs we detected Rickettsia amblyommatis and Rickettsia bellii in Amblyomma auriculatum, Amblyomma ovale and Amblyomma mixtum ticks obtained in a rural community in the Mexican state of Yucatan. This is the first report detecting both species for this state in Mexico, underpinning the importance of more routine surveillance.


Subject(s)
Ixodidae , Rickettsia , Ticks , Animals , Dogs , Humans , Ticks/microbiology , Mexico , Mammals , Ixodidae/microbiology , Brazil/epidemiology
3.
Viral Immunol ; 36(2): 101-109, 2023 03.
Article in English | MEDLINE | ID: mdl-36862827

ABSTRACT

Dengue virus (DENV) is the etiological agent of dengue, the most important mosquito-transmitted viral disease of humans worldwide. Enzyme-linked immunosorbent assays (ELISAs) designed to detect DENV IgM are commonly used for dengue diagnosis. However, DENV IgM is not reliably detected until ≥4 days after illness onset. Reverse transcription-polymerase chain reaction (RT-PCR) can diagnose early dengue but requires specialized equipment, reagents, and trained personnel. Additional diagnostic tools are needed. Limited work has been performed to determine whether IgE-based assays can be used for the early detection of vector-borne viral diseases, including dengue. In this study, we determined the efficacy of a DENV IgE capture ELISA for the detection of early dengue. Sera were collected within the first 4 days of illness onset from 117 patients with laboratory-confirmed dengue, as determined by DENV-specific RT-PCR. The serotypes responsible for the infections were DENV-1 and DENV-2 (57 and 60 patients, respectively). Sera were also collected from 113 dengue-negative individuals with febrile illness of undetermined etiology and 30 healthy controls. The capture ELISA detected DENV IgE in 97 (82.9%) confirmed dengue patients and none of the healthy controls. There was a high false positivity rate (22.1%) among the febrile non-dengue patients. In conclusion, we provide evidence that IgE capture assays have the potential to be explored for early diagnosis of dengue, but further research is necessary to address the possible false positivity rate among patients with other febrile illnesses.


Subject(s)
Antibodies, Viral , Dengue , Enzyme-Linked Immunosorbent Assay , Immunoglobulin E , Animals , Humans , Antibodies, Viral/immunology , Dengue Virus/immunology , Early Diagnosis , Enzyme-Linked Immunosorbent Assay/methods , Sensitivity and Specificity , Serogroup , Dengue/diagnosis , Dengue/immunology , Immunoglobulin E/immunology , False Positive Reactions
4.
Front Vet Sci ; 9: 1057686, 2022.
Article in English | MEDLINE | ID: mdl-36504864

ABSTRACT

Backyard animal husbandry is common in rural communities in developing countries and, given the conditions in which it occurs, it can increase the risk of disease transmission, such as arboviruses. To determine the presence of the Zika virus (ZIKV) and abundance of its arthropod vectors we evaluated the socioeconomic implications involved in its transmission in two highly vulnerable Mayan communities in the state of Yucatan that practice backyard farming. An analytical cross-sectional study was carried out throughout 2016 to understand socioeconomic variables and seasonal patterns in mosquito populations. We selected 20 households from each community. Social exclusion indicators were analyzed, human and domestic animals were sampled, and mosquitoes were collected and identified. Four out of eight indicators of social exclusion were higher than the reported national averages. We captured 5,825 mosquitoes from 16 species being Culex quinquefasciatus and Aedes aegypti the most abundant. The presence of chickens and human overcrowding in dwellings were the most significant factors (P = 0.026) associated with the presence of Ae. aegypti. Septic tanks (odds ratio = 6.64) and chickens (odds ratio = 27.41) in backyards were the main risk factors associated with the presence of immature states of Ae. aegypti in both communities. Molecular analysis to detect ZIKV was performed in blood samples from 416 humans, 1,068 backyard animals and 381 mosquito pools. Eighteen humans and 10 pig pools tested positive for ZIKV. Forty-three mosquito pools tested positive for flavivirus. Ten of the 43 pools of positive mosquitoes were sequenced, corresponding 3/10 to ZIKV and 1/10 to Dengue virus type 2. The findings obtained indicate the continuous circulation of Flavivirus (including ZIKV) in backyard environments in vulnerable communities, highlighting the importance of studying their transmission and maintenance in these systems, due that backyard animal husbandry is a common practice in these vulnerable communities with limited access to health services.

5.
Biosensors (Basel) ; 12(7)2022 Jul 07.
Article in English | MEDLINE | ID: mdl-35884298

ABSTRACT

Flavivirus detection in humans and mosquito reservoirs has been an important issue since it can cause a variety of illnesses and could represent a health problem in geographical zones where the vector is endemic. In this work, we designed and characterized a biosensor based on gold nanoparticles (AuNPs) and antibody 4G2 for the detection of dengue virus (DENV) in vitro, obtaining different conjugates (with different antibody concentrations). The AuNP-4G2 conjugates at concentrations of 1, 3, and 6 µg/mL presented an increase in the average hydrodynamic diameter compared to the naked AuNPs. Also, as part of the characterization, differences in the UV-Vis absorbance spectrum and electrophoretic migration were observed between the conjugated AuNPs (with BSA or antibody) and naked AuNPs. Additionally, we used this biosensor (AuNP-4G2 conjugate with 3 µg/mL antibody) in the assembly of a competitive lateral flow assay (LFA) for the development of an alternative test to detect the flavivirus envelope protein in isolated DENV samples as a future tool for dengue detection (and other flaviviruses) in the mosquito vector (Aedesaegypti) for the identification of epidemic risk regions. Functionality tests were performed using Dengue virus 2 isolated solution (TCID50/mL = 4.58 × 103) as a positive sample and PBS buffer as a negative control. The results showed that it is possible to detect Dengue virus in vitro with this gold nanoparticle-based lateral flow assay with an estimated detection limit of 5.12 × 102 PFU. We suggest that this biosensor could be used as an additional detection tool by coupling it to different point-of-care tests (POCT) for the easy detection of other flaviviruses.


Subject(s)
Biosensing Techniques , Dengue Virus , Metal Nanoparticles , Animals , Biosensing Techniques/methods , Gold , Humans , Immunoassay/methods
6.
Diabetes Metab Syndr ; 16(3): 102447, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35272174

ABSTRACT

BACKGROUND AND AIMS: The prevalence and incidence of infertility are increasing worldwide; they are associated with a significant economic and social impact. Infertility is defined as the inability to achieve pregnancy after 12 months or more of regular unprotected sex. In recent times, the male factor has gained importance and currently it contributes to approximately 50% of infertility cases. Multiple etiologies are stated, such as metabolic, anatomical, genetic or even idiopathic causes; however, the main cause is semen abnormalities. The aim of this manuscript is to provide a complete review of hormonal assessment of male infertility, as well as to review the physiology and pathophysiology related to the male gonadal axis. METHODS: This study is a narrative abstract carried out on basis of systematic bibliographic review, using articles indexed in PubMed/Medline, Scopus, Embase and Scielo, which were published during the last 20 years. RESULTS: The cornerstone of the evaluation of the hormonal status is semen analysis. Clinicians must rule out hypogonadism in those patients who present oligospermia and azoospermia, by determining levels of testosterone and gonadotropins, which provide the functionality status of the hypothalamic-pituitary-testicular axis. Evaluation of the adrenal, thyroid, and lactotroph axis are indicated in those patients with central hypogonadism. CONCLUSIONS: Despite advances in the diagnosis of male infertility, some causes are not fully understood, therefore, it is crucial to perform a timely hormonal evaluation of the male factor in infertile couples, in order to provide adequate treatment and improve fertility rates.


Subject(s)
Hypogonadism , Infertility, Male , Female , Humans , Infertility, Male/diagnosis , Infertility, Male/etiology , Male , Pregnancy , Semen Analysis/adverse effects , Testosterone
7.
Am J Trop Med Hyg ; 106(3): 896-899, 2022 01 24.
Article in English | MEDLINE | ID: mdl-35073512

ABSTRACT

We provide evidence of concurrent and close sequential infections between SARS-CoV-2 and select arboviruses-namely, chikungunya virus (CHIKV); dengue viruses 1, 2, and 3 (DENV1-3), and Zika virus (ZIKV)-in patients in Guerrero, southwest Mexico, in 2020-2021. The study population consisted of 176 febrile patients with laboratory evidence of SARS-CoV-2 infection. Sera from all patients were serologically and antigenically tested for seven arboviruses known to occur in Guerrero. Eighteen patients contained CHIKV IgM, six of whom also contained CHIKV RNA. Another 16 patients contained flavivirus antigen. The flaviviruses responsible for the infections were identified by plaque reduction neutralization test as DENV1 (two patients), DENV2 (five patients), DENV3 (three patients), ZIKV (three patients), and an undetermined flavivirus (three patients). In summary, we identified patients in Guerrero, Mexico, with concurrent or recent sequential infections between SARS-CoV-2 and select arboviruses, exemplifying the importance of performing differential diagnosis in regions where these viruses cocirculate.


Subject(s)
Arboviruses , COVID-19 , Chikungunya Fever , Coinfection , Dengue Virus , Dengue , Zika Virus Infection , Zika Virus , COVID-19/epidemiology , Dengue/diagnosis , Dengue Virus/genetics , Humans , Mexico/epidemiology , SARS-CoV-2 , Zika Virus/genetics , Zika Virus Infection/epidemiology
8.
Am J Trop Med Hyg ; 105(5): 1281-1284, 2021 10 30.
Article in English | MEDLINE | ID: mdl-34460419

ABSTRACT

The local public health authorities reported nine cases of chikungunya in Mexico in 2019, none of which occurred in Guerrero, a coastal state in the southwest. To test the hypothesis that chikungunya is grossly underreported in Mexico, acute sera were collected from 639 febrile patients from low-income households in Guerrero in 2019 and serologically assayed for chikungunya virus (CHIKV). Analysis of the sera by plaque reduction neutralization test revealed that 181 (28.3%) patients were seropositive for CHIKV. To identify patients with acute CHIKV infections, a subset of serum samples were tested for CHIKV-specific IgM by ELISA. Serum samples from 21 of 189 (11.1%) patients were positive. These patients met the chikungunya case definition established by the WHO. In conclusion, we provide evidence that CHIKV remains an important public health problem in Mexico and that the true number of cases is severely underestimated.


Subject(s)
Chikungunya Fever/blood , Chikungunya Fever/immunology , Chikungunya Fever/virology , Chikungunya virus/isolation & purification , Data Accuracy , Immunoglobulin M/blood , Public Health Surveillance , Adolescent , Adult , Aged , Aged, 80 and over , Chikungunya Fever/epidemiology , Child , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Male , Mexico/epidemiology , Middle Aged , Prevalence , Seroepidemiologic Studies , Young Adult
9.
Vector Borne Zoonotic Dis ; 21(6): 458-465, 2021 06.
Article in English | MEDLINE | ID: mdl-33944623

ABSTRACT

A clinical and entomological investigation was performed to identify flavivirus infections in humans and mosquitoes in impoverished areas of Guerrero, a coastal state in southwestern Mexico. A total of 639 patients with acute febrile illness and 830 resting female mosquitoes in low-income communities of Guerrero in 2019 were tested for evidence of flavivirus infection. Sera were collected from all patients and screened at a dilution of 1:20 by plaque reduction neutralization test (PRNT) using dengue virus (DENV)2. A total of 431 (67.4%) patients were seropositive. Sera from a subset of seropositive patients (n = 263) were tested for flavivirus NS1 by enzyme-linked immunosorbent assay. Forty-eight (18.3%) sera contained viral antigen. All NS1-positive sera were titrated and further tested by PRNT using DENV-1 to -4, St. Louis encephalitis virus, West Nile virus, and Zika virus (ZIKV). Seven patients were seropositive for DENV-1, five patients were seropositive for DENV-2, one patient was seropositive for DENV-3, and two patients each were seropositive for DENV-4 and ZIKV. The remainder had secondary flavivirus infections or antibodies to an undetermined flavivirus. Comparative PRNTs were also performed on 60 randomly selected NS1-negative sera, identifying patients seropositive for DENV-2, DENV-3, and ZIKV. The entomological investigation yielded 736 Aedes aegypti and 94 Culex quinquefasciatus that were sorted into 183 pools and 20 pools, respectively. Mosquitoes were assayed for flavivirus RNA by RT-PCR and Sanger sequencing. DENV-2 RNA was detected in three pools of A. aegypti. In summary, we provide evidence for the concurrent circulation of all four DENVs and ZIKV in Guerrero, Mexico. The public health authorities reported no cases of DENV-3, DENV-4, and ZIKV in Guerrero in 2019 and thus, we provide evidence of under-reporting in the region.


Subject(s)
Dengue Virus , Dengue , Zika Virus Infection , Zika Virus , Animals , Antibodies, Viral , Dengue/epidemiology , Dengue/veterinary , Dengue Virus/genetics , Female , Humans , Mexico/epidemiology , Zika Virus Infection/epidemiology , Zika Virus Infection/veterinary
10.
Parasit Vectors ; 14(1): 261, 2021 May 18.
Article in English | MEDLINE | ID: mdl-34006306

ABSTRACT

BACKGROUND: Zika virus (ZIKV) is an arthropod-borne virus (arbovirus) with an urban transmission cycle that primarily involves humans and Aedes aegypti. Evidence suggests that the evolution of some arboviruses is constrained by their dependency on alternating between disparate (vertebrate and invertebrate) hosts. The goals of this study are to compare the genetic changes that occur in ZIKV after serial passaging in mosquito or vertebrate cell lines or alternate passaging in both cell types and to compare the replication, dissemination, and transmission efficiencies of the cell culture-derived viruses in Ae. aegypti. METHODS: An isolate of ZIKV originally acquired from a febrile patient in Yucatan, Mexico, was serially passaged six times in African green monkey kidney (Vero) cells or Aedes albopictus (C6/36) cells or both cell types by alternating passage. A colony of Ae. aegypti from Yucatan was established, and mosquitoes were challenged with the cell-adapted viruses. Midguts, Malpighian tubules, ovaries, salivary glands, wings/legs and saliva were collected at various times after challenge and tested for evidence of virus infection. RESULTS: Genome sequencing revealed the presence of two non-synonymous substitutions in the premembrane and NS1 regions of the mosquito cell-adapted virus and two non-synonymous substitutions in the capsid and NS2A regions of both the vertebrate cell-adapted and alternate-passaged viruses. Additional genetic changes were identified by intrahost variant frequency analysis. Virus maintained by continuous C6/36 cell passage was significantly more infectious in Ae. aegypti than viruses maintained by alternating passage and consecutive Vero cell passage. CONCLUSIONS: Mosquito cell-adapted ZIKV displayed greater in vivo fitness in Ae. aegypti compared to the other viruses, indicating that obligate cycling between disparate hosts carries a fitness cost. These data increase our understanding of the factors that drive ZIKV adaptation and evolution and underscore the important need to consider the in vivo passage histories of flaviviruses to be evaluated in vector competence studies.


Subject(s)
Aedes/virology , Mosquito Vectors/virology , Serial Passage/methods , Zika Virus Infection/transmission , Zika Virus/genetics , Zika Virus/physiology , Animals , Cell Line , Chlorocebus aethiops , Disease Vectors , Genetic Fitness , Insecta/cytology , Salivary Glands/virology , Vero Cells , Viral Load
11.
J Parasitol ; 107(1): 29-38, 2021 01 01.
Article in English | MEDLINE | ID: mdl-33535232

ABSTRACT

This study was carried out to identify the ectoparasites that infest owned dogs in the state of Tabasco, Mexico. In total, 1,302 dogs were sampled in the 5 ecological regions of Tabasco. The dog owners were surveyed to identify the factors associated with infestations. Ectoparasites were identified using taxonomic keys. Eleven species of ectoparasites were observed. General prevalence was 26.65%. Rhipicephalus sanguineus and Ctenocephalides felis were the most prevalent and abundant ectoparasites. The most important factors associated with ectoparasite infestations in the studied dogs were living outdoors, being a non-purebred, having short hair, being dark-haired, and having a body condition <3. Ectoparasite studies such as the one presented herein generate important information to create control programs focused on decreasing infestations in companion animals and thus the likelihood of zoonotic transmission of pathogens.


Subject(s)
Dog Diseases/epidemiology , Dog Diseases/parasitology , Dogs/classification , Ectoparasitic Infestations/veterinary , Animals , Animals, Domestic , Dog Diseases/transmission , Ectoparasitic Infestations/epidemiology , Ectoparasitic Infestations/parasitology , Ectoparasitic Infestations/transmission , Female , Male , Mexico/epidemiology , Ownership , Phthiraptera/classification , Prevalence , Siphonaptera/classification , Surveys and Questionnaires , Ticks/classification
12.
Emerg Infect Dis ; 27(2): 574-577, 2021 02.
Article in English | MEDLINE | ID: mdl-33496242

ABSTRACT

Evidence suggests that pigs seroconvert after experimental exposure to Zika virus and are potential sentinels. We demonstrate that pigs are also susceptible to natural Zika virus infection, shown by the presence of antibodies in domestic pigs in Yucatan, Mexico. Zika virus RNA was detected in 5 species of mosquitoes collected inside pigpens.


Subject(s)
Aedes , Culex , Zika Virus Infection , Zika Virus , Animals , Mexico/epidemiology , Mosquito Vectors , Swine , Zika Virus/genetics , Zika Virus Infection/epidemiology , Zika Virus Infection/veterinary
13.
J Infect Dev Ctries ; 14(12): 1442-1447, 2020 12 31.
Article in English | MEDLINE | ID: mdl-33378288

ABSTRACT

INTRODUCTION: Dirofilaria immitis is a nematode that affects human health in several countries of the world. This study was conducted to examine whether serum samples from the owners of microfilaremic dogs present immunoreactivity to parasite proteins. METHODOLOGY: Eight serum samples from the owners of microfilaremic dogs were examined. Total proteins were extracted from adult worms and 12% SDS-PAGE was performed. The gel was electroblotted to a nitrocellulose membrane, and a Western blot (WB) was performed. Reactive bands of 22, 33, 39, 49, and 63 kDa in WB were excised from the gel and analyzed by mass spectrometry (MS). RESULTS: The MS results showed the presence of 10 different proteins of D. immitis recognized by the human serum samples. CONCLUSIONS: These results indicate that in endemic areas of D. immitis, owners of infected dogs recognize specific proteins of the parasite, suggesting a possible infection.


Subject(s)
Antibodies, Helminth/blood , Dirofilaria immitis/chemistry , Dirofilariasis/immunology , Dog Diseases/parasitology , Helminth Proteins/immunology , Ownership , Adult , Aged , Animals , Blotting, Western , Dirofilaria immitis/genetics , Dirofilaria immitis/immunology , Dirofilariasis/transmission , Dogs , Female , Humans , Male , Mexico , Microfilariae/genetics , Microfilariae/immunology , Middle Aged , Pets/parasitology
14.
J Parasitol ; 106(6): 835-842, 2020 11 12.
Article in English | MEDLINE | ID: mdl-33378530

ABSTRACT

Numerous arthropod taxa are important in human and veterinary medicine. The salivary secretions and feces of arthropods can cause allergic reactions in host vertebrates or harbor pathogens. Also, bites can be a risk factor for secondary infections. Documenting the diversity of arthropods of medical and veterinary importance remains an important aspect of disease control and prevention. We provide new records of ectoparasitic arthropods from Mexico that are of potential medical or veterinary relevance. Scanning electron microscopy along with amplification and sequencing of a fragment of the mitochondrial gene (16S rRNA) was used to confirm some species identities. We report the cat louse Felicola subrostratus from cats and the chewing louse Heterodoxus spiniger from dogs, which are common ectoparasites but largely not reported in Mexico. The chigger Eutrombicula alfreddugesi is common on wild lizards (Squamata). For the first time, E. alfreddugesi is reported on Hemidactylus frenatus (common house gecko). This reptile has a close relationship with humans and its chiggers can cause dermatitis (i.e., trombiculiasis) or transmit pathogens. In addition, the common bed bug Cimex lectularius is reported for the first time in the state of Yucatan, an atypical area for its natural distribution. Phylogenetic analysis revealed that Cimex lectularius from Yucatan is closely related to genetic sequences of Cimex lectularius from China. Knowing the regional distribution of arthropods allows the design and implementation of prevention strategies for those that have potential roles as reservoirs or vectors.


Subject(s)
Arthropod Vectors/classification , Cat Diseases/parasitology , Dog Diseases/parasitology , Lice Infestations/veterinary , Lizards/parasitology , Mite Infestations/veterinary , Animals , Arthropod Vectors/ultrastructure , Bedbugs/classification , Cats , Dogs , Female , Humans , Ischnocera/ultrastructure , Lice Infestations/parasitology , Male , Mexico , Microscopy, Electron, Scanning , Mite Infestations/parasitology , Siphonaptera/ultrastructure , Trombiculidae/ultrastructure
15.
N Engl J Med ; 383(25): 2407-2416, 2020 12 17.
Article in English | MEDLINE | ID: mdl-33176093

ABSTRACT

BACKGROUND: The efficacy of public health measures to control the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has not been well studied in young adults. METHODS: We investigated SARS-CoV-2 infections among U.S. Marine Corps recruits who underwent a 2-week quarantine at home followed by a second supervised 2-week quarantine at a closed college campus that involved mask wearing, social distancing, and daily temperature and symptom monitoring. Study volunteers were tested for SARS-CoV-2 by means of quantitative polymerase-chain-reaction (qPCR) assay of nares swab specimens obtained between the time of arrival and the second day of supervised quarantine and on days 7 and 14. Recruits who did not volunteer for the study underwent qPCR testing only on day 14, at the end of the quarantine period. We performed phylogenetic analysis of viral genomes obtained from infected study volunteers to identify clusters and to assess the epidemiologic features of infections. RESULTS: A total of 1848 recruits volunteered to participate in the study; within 2 days after arrival on campus, 16 (0.9%) tested positive for SARS-CoV-2, 15 of whom were asymptomatic. An additional 35 participants (1.9%) tested positive on day 7 or on day 14. Five of the 51 participants (9.8%) who tested positive at any time had symptoms in the week before a positive qPCR test. Of the recruits who declined to participate in the study, 26 (1.7%) of the 1554 recruits with available qPCR results tested positive on day 14. No SARS-CoV-2 infections were identified through clinical qPCR testing performed as a result of daily symptom monitoring. Analysis of 36 SARS-CoV-2 genomes obtained from 32 participants revealed six transmission clusters among 18 participants. Epidemiologic analysis supported multiple local transmission events, including transmission between roommates and among recruits within the same platoon. CONCLUSIONS: Among Marine Corps recruits, approximately 2% who had previously had negative results for SARS-CoV-2 at the beginning of supervised quarantine, and less than 2% of recruits with unknown previous status, tested positive by day 14. Most recruits who tested positive were asymptomatic, and no infections were detected through daily symptom monitoring. Transmission clusters occurred within platoons. (Funded by the Defense Health Agency and others.).


Subject(s)
COVID-19 Testing , COVID-19/transmission , Disease Transmission, Infectious/statistics & numerical data , Military Personnel , Quarantine , SARS-CoV-2/isolation & purification , Asymptomatic Infections , COVID-19/diagnosis , COVID-19/epidemiology , Genome, Viral , Humans , Male , Phylogeny , Real-Time Polymerase Chain Reaction , Risk Factors , SARS-CoV-2/genetics , South Carolina/epidemiology , Whole Genome Sequencing , Young Adult
16.
Exp Appl Acarol ; 82(3): 431-440, 2020 Nov.
Article in English | MEDLINE | ID: mdl-33025238

ABSTRACT

The present study was carried out to identify Rickettsia species with zoonotic potential in ticks collected from dogs in a rural area in Tabasco, Mexico. In total 197 Amblyomma maculatum ticks were collected from 40 domestic dogs. The collected specimens were pooled and subjected to DNA extraction. A fragment (380 bp) of citrate synthase gene (gltA) was amplified by polymerase chain reaction (PCR) using universal primers for Rickettsia. A second PCR was later performed to amplify a fragment (420 bp) of the outer membrane protein B gene (ompB). The PCR products were purified, sequenced and compared using the basic local alignment search tool (BLAST). Twenty out of 40 (50%) tick pools assayed were positive for rickettsial DNA using both primer pairs. The consensus sequence obtained from the ompB gene fragments showed 99.5-100% of identity with strains of Rickettsia parkeri. This study provides the first molecular evidence of the presence of R. parkeri in A. maculatum ticks infesting domestic dogs from southeastern Mexico. Close contact between dogs and humans should lead to consider the infection caused by this species of Rickettsia among the differential diagnoses for people of Tabasco, Mexico, who show acute febrile syndrome associated to inoculation eschar and have a clinical history of tick exposure.


Subject(s)
Dogs/parasitology , Rickettsia/isolation & purification , Ticks/microbiology , Animals , Mexico , Rickettsia/genetics
18.
Parasitol Int ; 75: 102042, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31862425

ABSTRACT

Hymenolepidid cestodes of synanthropic rodents represent a risk for public health. In order to describe the occurrence of hymenolepidids in children and the role of rodents as a potential source of infection, we conducted a morphological and molecular survey on cestodes in two rural villages from Yucatan, Mexico. One hundred and thirty-five stool samples from children (64 from Paraíso and 71 from Xkalakdzonot), 233 Mus musculus (159 from Paraíso and 74 from Xkalakdzonot) and 125 Rattus rattus (7 from Paraíso and 118 from Xkalakdzonot) were analyzed for the presence of cestodes. Three hymenolepidid species were identified morphologically: Hymenolepis nana in 7.8% of children from Paraíso, Hymenolepis microstoma in 4.4% of M. musculus from Paraíso and Hymenolepis diminuta in 15.3% of R. rattus from Xkalakdzonot. The molecular characterization and phylogenetic analysis based on mitochondrial cytochrome c subunit 1 (CO1) gene and ribosomal internal transcribed spacer 1 (ITS1) region, confirmed the identity of the three cestodes isolated from Yucatan. Phylogeny of the CO1 gene identified intraspecific genetic differences within H. nana ranging from 0 to 5%, in H. microstoma from 0 to 0.4%, and in H. diminuta ranged from 0 to 6.5% which suggests, the presence of complex species within H. nana and H. diminuta infecting humans and rodents, as reported by other authors. Based on the morphological and molecular results, and the epidemiological evidence, infections with H. nana suggest a non-zoonotic transmission; however, the presence of H. microstoma and H. diminuta in synanthropic rodents serve as a possible source for human infection.


Subject(s)
Hymenolepiasis/epidemiology , Hymenolepiasis/veterinary , Hymenolepis/isolation & purification , Mice , Rats , Rodent Diseases/epidemiology , Adolescent , Animals , Child , Child, Preschool , Humans , Hymenolepiasis/parasitology , Hymenolepis diminuta/isolation & purification , Hymenolepis nana/isolation & purification , Infant , Mexico/epidemiology , Phylogeny , Prevalence , Rodent Diseases/parasitology , Rodentia
19.
Ciencias y Salud ; 4(2): [99-107], 20200000. tab, graf
Article in Spanish | LILACS | ID: biblio-1369326

ABSTRACT

Objetivo: la inesperada ausencia del signo de polipunta o de polipunta onda (PPO) en el electroencefalograma (EEG) de dos casos, de 29 y 51 años, respectivamente, del Síndrome Lance Adams (SLA), que hemos visto y publicado con anterioridad, nos motivó a investigar la edad cuando este signo tiende a extinguirse, dejando de ser obligatorio para diagnosticar SLA a pacientes de edad madura. Métodos: de una muestra de 7137 trazados se incluyeron 6939, tras excluir 198 por referimientos no identificables. Estos EEG del Centro de Rehabilitación y el Centro Médico de la Universidad Central del Este (UCE), fueron realizados con electroencefalógrafos Nervus y Cadwell, de manera respectiva. Se revisaron buscando la presencia de PPO para estudiar la edad, la patología sospechada en cada indicación y el género de los pacientes. Resultados: PPO fue encontrada en 293 casos: 4.22 % de la muestra total. En 272 habría ocurrido antes de los 17 años, con la gráfica mostrando una elevación inicial máxima a las nueve. En cambio, de los 18 a los 65 solo apareció la PPO en 18 casos. 14 pacientes mostraron supresión de paroxismo o patrones de electro depresión sin PPO. Conclusión: la polipunta/polipunta onda prácticamente desaparece a los 17 años, a mayor edad, por lo tanto, el signo PPO deja de ser obligatorio para el diagnóstico del SLA en pacientes mayores. Es más frecuente en epilépticos y en varones


Objective: Unexpected absence of polyspike/polyspike & wave sign (PPW) in the EEG of our 29 and 51-year old published cases of Lance Adams Syndrome (LAS), prompted us to investigate the age when this sign may nearly disappear. This in order of considering it not obligatory for late LAS diagnosis. Methods: Inclusion consisted of a sample of 7137 recordings performed at the Rehabilitation Center and the Universidad Central del Este's (UCE) teaching clinic (Nervus and Cadwell respectively). Excluded were 198 for unidentifiable indications. PPW was searched in order to study patient's age, suspected pathology plus gender. Results: PPW was found in 293cases: 4.22% of the total sample: in 275.it occurred before the age of 17 with curve showing an initial tip at nine while between 18 and 65 only 18 cases showed it. Incidentally 14 patients showed Burst suppression or electro-decrement patterns without PPW. The most common indication pathology was Epilepsy followed by learning disability. Finally it was more frequent in 176(63.9%) male vs. 113(36.1%) in female cases: ratio 1.56 to 1. however not significant for the gender ratio in the total EEG sample is 1.55 to 1. Conclusion: PPW nearly disappears after the age of seventeen, perhaps explaining rarity in advanced aged SLA. It is more frequent in Epilepsy EEG indications and in the male


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Epilepsies, Myoclonic , Electroencephalography
20.
Sci Rep ; 9(1): 6222, 2019 04 17.
Article in English | MEDLINE | ID: mdl-30996290

ABSTRACT

High-throughput RNA sequencing is a powerful tool that allows us to perform gene prediction and analyze tissue-specific overexpression of genes, but also at species level comparisons can be performed, although in a more restricted manner. In the present study complete liver transcriptomes of five tropical bat species were De novo assembled and annotated. Highly expressed genes in the five species were involved in glycolysis and lipid metabolism pathways. Cross-species differential expression analysis was conducted using single copy orthologues shared across the five species. Between 22 and 29 orthologs were upregulated for each species. We detected upregulated expression in Artibeus jamaicensis genes related to fructose metabolism pathway. Such findings can be correlated with A. jamaicensis dietary habits, as it was the unique frugivorous species included. This is the first report of transcriptome assembly by RNA-seq in these species, except for A. jamaicensis and as far as our knowledge is the first cross-species comparisons of transcriptomes and gene expression in tropical bats.


Subject(s)
Chiroptera/classification , Chiroptera/genetics , Molecular Sequence Annotation , Transcriptome , Animals , Gene Expression , Gene Expression Profiling , Glycolysis/genetics , High-Throughput Nucleotide Sequencing , Lipid Metabolism/genetics , Liver , Phylogeny , RNA-Seq , Sequence Analysis, RNA
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