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1.
Emerg Microbes Infect ; 9(1): 496-504, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32106784

RESUMO

The mesoniviruses (MESOVs) belong to the newly described Mesoniviridae family (Order: Nidovirales). They have never been reported in Senegal until recently during a study in arbovirus emergence with the detection of a new species of MESOV named Dianke virus (DKV) from common mosquitoes from eastern Senegal. Actually, their vector competence for this newly described DKV is unknown. We, therefore, estimated the vector competence of Culex tritaeniorhynchus, Culex quinquefasciatus, Aedes aegypti, and Anopheles gambiae mosquitoes collected in Senegal for DKV using oral infection. Whole bodies, legs/wings, and saliva samples were tested for DKV by RT-PCR to estimate infection, dissemination, and transmission rates. The infectivity of virus particles in the saliva was confirmed by infecting C6/36 cells. Virus transmission rates were up to 95.45% in Culex tritaeniorhynchus, 28% in Cx. quinquefasciatus and 9.09% in Aedes aegypti. Viral particles in the saliva were confirmed infectious by C6/36 cell culture. An. gambiae was able to disseminate DKV only at 20 days post-infection. This study shows that Culex mosquitoes are more competent than Ae. aegypti for DKV, while Anopheles gambiae is not likely a competent vector.


Assuntos
Aedes/virologia , Mosquitos Vetores , Nidovirales , Animais , Linhagem Celular , Feminino , Infecções por Nidovirales/transmissão , Saliva/virologia , Senegal
2.
BMC Infect Dis ; 19(1): 954, 2019 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-31706275

RESUMO

BACKGROUND: Mumps is a vaccine-preventable disease but outbreaks have been reported in persons vaccinated with two doses of MMR vaccine. The objective was to describe the demographic features, vaccination effectiveness and genetic mumps virus diversity among laboratory-confirmed cases between 2007 and 2011 in Catalonia. METHODS: Cases and outbreaks of mumps notified to the notifiable diseases system of Catalonia between 2007 and 2011 retrospectively registered were included. Public health care centres provided written immunization records to regional public health staff to determine the vaccination history. Saliva and serum specimens were collected from suspected cases for laboratory-confirmation using real-time reverse-transcriptase PCR (rtRT-PCR) or serological testing. Phylogenetic analysis of the complete SH gene (316 nucleotides) and complete coding HN protein (1749 nucleotides) sequences was made. Categorical variables were compared using the Chi-square or Fisher's tests and continuous variables using the Student test. Vaccination effectiveness by number of MMR doses was estimated using the screening method. RESULTS: During the study period, 581 confirmed cases of mumps were notified (incidence rate 1.6 cases/100,000 persons-year), of which 60% were male. Three hundred sixty-four laboratory-confirmed cases were reported, of which 44% were confirmed by rtRT-PCR. Of the 289 laboratory-confirmed cases belonging to vaccination cohorts, 33.5% (97) had received one dose of MMR vaccine and 50% (145) two doses. Based on phylogenetic analyses of 316-nucleotide and 174-nucleotide SH sequences, the viruses belonging to viral genotypes were: genotype G (126), genotype D (23), genotype H (2), genotype F (2), genotype J (1), while one remained uncharacterized. Amino acid differences were detected between circulating strains and the Jeryl Lynn vaccine strains, although the majority of amino acid substitutions were genotype-specific. Fifty-one outbreaks were notified that included 324 confirmed mumps cases. Genotype G was the most frequent genotype detected. The family (35%), secondary schools (25%) and community outbreaks (18%) were the most frequent settings. CONCLUSIONS: Our study shows that genotype G viruses are the most prevalent in Catalonia. Most cases occurred in people who had received two doses of MMR, suggesting inadequate effectiveness of the Jeryl Lynn vaccine strain. The possible factors related are discussed.


Assuntos
Variação Genética , Vacina contra Sarampo-Caxumba-Rubéola/imunologia , Vírus da Caxumba/genética , Vacinação/estatística & dados numéricos , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Genótipo , Humanos , Lactente , Masculino , Caxumba/epidemiologia , Caxumba/imunologia , Caxumba/virologia , Vírus da Caxumba/classificação , Vírus da Caxumba/isolamento & purificação , Filogenia , Estudos Retrospectivos , Saliva/virologia , Espanha/epidemiologia , Proteínas Virais/classificação , Proteínas Virais/genética , Proteínas Virais/metabolismo , Adulto Jovem
3.
Parasit Vectors ; 12(1): 484, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31619269

RESUMO

BACKGROUND: Aedes vexans (Meigen) is considered a nuisance species in central Europe and the Mediterranean region. It is an anthropophilic and mammalophilic floodwater mosquito involved in the transmission of several arboviruses. Rift Valley fever (RVF) is a relevant mosquito-borne zoonosis, affecting mainly humans and ruminants, that causes severe impact in public health and economic loses. Due to globalization and climate change, the European continent is threatened by its introduction. The main purpose of the present study was to evaluate the vector competence of a European field-collected Ae. vexans population. METHODS: Aedes vexans field-collected larvae were reared in the laboratory under field-simulated conditions. To assess the vector competence for Rift Valley fever phlebovirus (RVFV) transmission, adult F0 females were exposed to infectious blood meals containing the 56/74 RVFV strain. Additionally, intrathoracic inoculations with the same virus strain were performed to evaluate the relevance of the salivary gland barriers. Natural circulation of alphavirus, flavivirus and phlebovirus was also tested. RESULTS: To our knowledge, an autochthonous Ae. vexans population was experimentally confirmed as a competent vector for RVFV for the first time. This virus was capable of infecting and disseminating within the studied Ae. vexans mosquitoes. Moreover, infectious virus was isolated from the saliva of disseminated specimens, showing their capacity to transmit the virus. Additionally, a natural infection with a circulating Mosquito flavivirus was detected. The co-infection with the Mosquito flavivirus seemed to modulate RVFV infection susceptibility in field-collected Ae. vexans, but further studies are needed to confirm its potential interference in RVFV transmission. CONCLUSIONS: Our results show that field-collected European Ae. vexans would be able to transmit RVFV in case of introduction into the continent. This should be taken into consideration in the design of surveillance and control programmes.


Assuntos
Aedes/virologia , Mosquitos Vetores/virologia , Febre do Vale de Rift/transmissão , Vírus da Febre do Vale do Rift/fisiologia , Zoonoses/transmissão , Aedes/citologia , Aedes/fisiologia , Alphavirus/isolamento & purificação , Animais , Bovinos , Linhagem Celular , Galinhas , Células Clonais , Europa (Continente) , Feminino , Flavivirus/isolamento & purificação , Inundações , Humanos , Mosquitos Vetores/fisiologia , Phlebovirus/isolamento & purificação , Chuva , Vírus da Febre do Vale do Rift/isolamento & purificação , Ruminantes , Saliva/virologia , Espanha , Organismos Livres de Patógenos Específicos , Células Vero , Água/parasitologia , Zoonoses/virologia
4.
PLoS Negl Trop Dis ; 13(10): e0007783, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31589616

RESUMO

The case-fatality rate of yellow fever virus (YFV) is one of the highest among arthropod-borne viruses (arboviruses). Although historically, the Asia-Pacific region has remained free of YFV, the risk of introduction has never been higher due to the increasing influx of people from endemic regions and the recent outbreaks in Africa and South America. Singapore is a global hub for trade and tourism and therefore at high risk for YFV introduction. Effective control of the main domestic mosquito vector Aedes aegypti in Singapore has failed to prevent re-emergence of dengue, chikungunya and Zika viruses in the last two decades, raising suspicions that peridomestic mosquito species untargeted by domestic vector control measures may contribute to arbovirus transmission. Here, we provide empirical evidence that the peridomestic mosquito Aedes malayensis found in Singapore can transmit YFV. Our laboratory mosquito colony recently derived from wild Ae. malayensis in Singapore was experimentally competent for YFV to a similar level as Ae. aegypti controls. In addition, we captured Ae. malayensis females in one human-baited trap during three days of collection, providing preliminary evidence that host-vector contact may occur in field conditions. Finally, we detected Ae. malayensis eggs in traps deployed in high-rise building areas of Singapore. We conclude that Ae. malayensis is a competent vector of YFV and re-emphasize that vector control methods should be extended to target peridomestic vector species.


Assuntos
Aedes/virologia , Mosquitos Vetores/virologia , Febre Amarela/virologia , Vírus da Febre Amarela/fisiologia , Aedes/crescimento & desenvolvimento , Animais , Feminino , Interações Hospedeiro-Patógeno/fisiologia , Humanos , Mosquitos Vetores/fisiologia , Saliva/virologia , Singapura/epidemiologia , Febre Amarela/epidemiologia , Febre Amarela/transmissão
5.
Arch Virol ; 164(11): 2811-2817, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31471723

RESUMO

Rabies remains a public health threat in China, and most transmissions are dog-mediated. In this study, we studied 31 clinically diagnosed human rabies patients that had been scratched or bitten by dogs. Real-time reverse transcription polymerase chain reaction (RT-qPCR) and nested RT-PCR were performed on saliva samples or cerebrospinal fluid, and samples from 28 patients tested positive for rabies virus. A total of one near-complete genome sequence, 15 complete glycoprotein (G) gene sequences, and five partial G gene sequences were determined. Phylogenetic analysis was performed, based on complete G gene sequences, using the maximum-likelihood method. The results indicated that the isolates belonged to the lyssavirus genotype I lineage and China I lineage. The Chinese rabies virus can be divided into six major lineages. The China I lineage was the dominant clade and could be divided into four subclades. Isolates 17HN19, 17HN75, and 18HN162 fell within clade IC subgroup, and the other isolates were assigned to the clade IA subgroup. This study provides epidemiological and genetic information on rabies incidence in humans.


Assuntos
Líquido Cefalorraquidiano/virologia , Vírus da Raiva/classificação , Vírus da Raiva/genética , Raiva/epidemiologia , Saliva/virologia , Adolescente , Adulto , Idoso , Animais , Criança , China/epidemiologia , Doenças do Cão/virologia , Cães , Feminino , Genoma Viral/genética , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Raiva/virologia , Vírus da Raiva/isolamento & purificação , Adulto Jovem
6.
Indian J Med Res ; 149(6): 771-777, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31496530

RESUMO

Background & objectives: Chikungunya virus (CHIKV), a mosquito-borne arthritogenic virus causes infections ranging from febrile illness to debilitating polyarthralgia in humans. Re-emergence of the virus has affected millions of people in Africa and Asia since 2004. During the outbreak, a new lineage of the virus has evolved as an adaptation for enhanced replication and transmission by Aedes albopictus mosquito. A study was designed to compare the susceptibility of four vertebrate cell lines, namely Vero E6 (African green monkey kidney), BHK-21 (Baby hamster kidney), RD (human rhabdomyosarcoma), A-549 (human alveolar basal epithelial cell) and C6/36 (Ae. albopictus) to Asian genotype and two lineages of East, Central and South African (E1:A226 and E1:A226V) of CHIKV. Methods: One-step growth kinetics of different CHIKV strains was carried out in the above five cell lines to determine the growth kinetics and virus yield. Virus titre was determined by 50 per cent tissue culture infectious dose assay and titres were calculated by the Reed and Muench formula. Growth and virus yield of the three strains in Ae. aegypti mosquitoes was studied by intrathoracic inoculation and virus titration in Vero E6 cell line. Results: Virus titration showed Vero E6, C6/36 and BHK-21 cell lines are high virus yielding with all the three lineages while RD and A-549 yielded low virus titres. C6/36 cell line was the most sensitive and yielded the maximum titre. Ae. aegypti mosquitoes, when inoculated with high titre virus, yielded an almost equal growth with the three strains while rapid growth of E1:A226V and Asian strain was observed with 1 log virus. Interpretation & conclusions: C6/36 cell line was found to be the most sensitive and high yielding for CHIKV irrespective of lineages while Vero E6 and BHK-21 cell lines yielded high titres and may find application for vaccine/diagnostic development. Infection of Ae. aegypti mosquitoes with the three CHIKV strains gave almost identical pattern of growth.


Assuntos
Aedes/virologia , Febre de Chikungunya/virologia , Vírus Chikungunya/crescimento & desenvolvimento , Culicidae/virologia , Células A549/virologia , África/epidemiologia , Animais , Ásia/epidemiologia , Febre de Chikungunya/epidemiologia , Febre de Chikungunya/genética , Vírus Chikungunya/genética , Vírus Chikungunya/patogenicidade , Surtos de Doenças , Genótipo , Humanos , Mosquitos Vetores/genética , Mosquitos Vetores/crescimento & desenvolvimento , Saliva/virologia , Células Vero/virologia
7.
Int J Infect Dis ; 87: 117-118, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31430537

RESUMO

Rabies is a common zoonotic viral infection worldwide. Numerous animals can transmit the virus to humans, but dogs are the main ones. Despite the high incidence of animal bites overall in Saudi Arabia, of which most are dog bites, no single case of confirmed local human rabies has been reported. This article reports the case of a 12-year-old boy who lived with his family in a village in Jazan region in the southeast area of Saudi Arabia. He presented with signs suggestive of rabies. Saliva testing by rabies PCR was positive, confirming this as the first case of local human rabies in Saudi Arabia. The management plan followed the Milwaukee protocol, but the patient unfortunately died after 13 days of admission.


Assuntos
Raiva/virologia , Zoonoses/virologia , Animais , Mordeduras e Picadas/virologia , Criança , Doenças do Cão/virologia , Cães , Humanos , Masculino , Raiva/diagnóstico , Vírus da Raiva/classificação , Vírus da Raiva/genética , Vírus da Raiva/isolamento & purificação , Saliva/virologia , Arábia Saudita , Zoonoses/diagnóstico , Zoonoses/transmissão
8.
Parasit Vectors ; 12(1): 384, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31366369

RESUMO

BACKGROUND: Cache Valley virus (CVV; Bunyavirales, Peribunyaviridae) is a mosquito-borne arbovirus endemic in North America. Although severe diseases are mainly observed in pregnant ruminants, CVV has also been recognized as a zoonotic pathogen that can cause fatal encephalitis in humans. Human exposures to CVV and its related subtypes occur frequently under different ecological conditions in the New World; however, neurotropic disease is rarely reported. High prevalence rates of neutralizing antibodies have been detected among residents in several Latin American cities. However, zoophilic mosquito species involved in the enzootic transmission are unlikely to be responsible for the transmission leading to human exposures to CVV. Mechanisms that lead to frequent human exposures to CVV remain largely unknown. In this study, competence of two anthropophilic mosquitoes, Aedes albopictus and Ae. aegypti, for CVV was determined using per os infection to determine if these species could play a role in the transmission of CVV in the domestic and peridomestic settings of urban and suburban areas. RESULTS: Aedes albopictus were highly susceptible to CVV whereas infection of Ae. aegypti occurred at a significantly lower frequency. Whilst the dissemination rates of CVV were comparable in the two species, the relatively long period to attain maximal infectious titer in Ae. aegypti demonstrated a significant difference in the replication kinetics of CVV in these species. Detection of viral RNA in saliva suggests that both Ae. albopictus and Ae. aegypti are competent vectors for CVV under laboratory conditions. CONCLUSIONS: Differential susceptibility to CVV was observed in Ae. albopictus and Ae. aegypti, reflecting their relatively different capacities for vectoring CVV in nature. The high susceptibility of Ae. albopictus to CVV observed in this study suggests its potential role as an efficient vector for CVV. Complemented by the reports of multiple CVV isolates derived from Ae. albopictus, our finding provides the basis for how the dispersal of Ae. albopictus across the New World may have a significant impact on the transmission and ecology of CVV.


Assuntos
Aedes/virologia , Vírus Bunyamwera/fisiologia , Infecções por Bunyaviridae/transmissão , Mosquitos Vetores/virologia , Zoonoses/transmissão , Zoonoses/virologia , Aedes/fisiologia , Animais , Infecções por Bunyaviridae/virologia , Cidades , Feminino , Humanos , América do Norte , RNA Viral/análise , Saliva/virologia , Carga Viral , Replicação Viral
9.
Indian J Med Microbiol ; 37(1): 24-28, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31424006

RESUMO

Introduction: Varicella outbreaks are known to occur in developing nations as vaccine coverage is still low. Material and Methods: In the present study, an institutional outbreak from Chandigarh, India, is reported wherein the utility of non-invasive samples such as saliva and urine was studied for the molecular diagnosis of varicella by conventional polymerase chain reaction (PCR), real-time PCR and real-time loop-mediated isothermal amplification (real-time LAMP). Results: The results of the present study showed that saliva and urine samples can be used for outbreak investigation of varicella compared to varicella-zoster virus DNA in vesicular swab samples with reasonable sensitivity. Conclusion: Thus, molecular techniques may be useful in the early identification of the outbreak and timely isolation, and the treatment of cases can further prevent its spread.


Assuntos
Varicela/diagnóstico , Varicela/epidemiologia , Técnicas de Diagnóstico Molecular/métodos , Saliva/virologia , Urina/virologia , Adolescente , Anticorpos Antivirais/sangue , Varicela/imunologia , Criança , Bem-Estar da Criança , DNA Viral/análise , Surtos de Doenças/estatística & dados numéricos , Feminino , Instalações de Saúde , Herpesvirus Humano 3/genética , Herpesvirus Humano 3/imunologia , Herpesvirus Humano 3/isolamento & purificação , Humanos , Índia/epidemiologia , Masculino , Técnicas de Amplificação de Ácido Nucleico/métodos , Reação em Cadeia da Polimerase
10.
Talanta ; 205: 120091, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31450455

RESUMO

Many studies have demonstrated that metal-organic frameworks (MOFs) are universal fluorescence quenchers for DNA/RNA detection. Nevertheless, the structural stability of many MOFs is relatively weak, which limits their practical applications. Thus, it remains a great interest to develop constitutionally stable nano biosensor suitable for application in the complex environment. Herein, a new angle of nitrogen-doped porous carbon (NPC) obtained from MOFs-based precursors by virtue of a simple method was applied as a nano biosensor for the fluorescence detection of Zika virus (ZIKV) RNA sequences. The fluorescence signal capturing was carried out by using a charge-coupled device (CCD)-based imaging system. The NPC could adsorb TAMRA-tagged ZIKV RNA probe (P-DNA) to form P-DNA@NPC complex accompanied by substantial fluorescence quenching. Upon adding the complementary target RNA (T-RNA), the P-DNA could release from NPC by forming a double-stranded hybrid and induce the fluorescence recovery. The P-DNA@NPC complex was valid and reliable for ZIKV RNA sequences assay with a limit of detection (LoD) at 0.23 nM, which is superior to many of the previously reported fluorescent DNA sensors. Moreover, it could distinguish mismatched RNA and was effective in detecting ZIKV RNA sequences spiked in the human saliva sample. We envision that this study would offer an interesting new angle on the potential integrating application of carbon nanomaterials and CCD-based fluorescence imaging platform in the field of nucleic acid assay.


Assuntos
Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , RNA Viral/análise , Infecção por Zika virus/virologia , Zika virus/genética , Carbono/química , Desenho de Equipamento , Fluorescência , Humanos , Limite de Detecção , Estruturas Metalorgânicas , Nitrogênio/química , Porosidade , Saliva/virologia , Sensibilidade e Especificidade , Espectrometria de Fluorescência/instrumentação , Espectrometria de Fluorescência/métodos
11.
Trials ; 20(1): 396, 2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-31272495

RESUMO

BACKGROUND: The introduction of pre-exposure prophylaxis (PrEP) for human immunodeficiency virus-1 (HIV-1) prevention in Africa presents new challenges for health systems that are already overburdened because PrEP delivery requires frequent clinic visits (generally every 3 months) for HIV-1 testing and PrEP refills. HIV-1 self-testing (HIVST) has the potential to improve the efficiency of PrEP delivery by decreasing the number of clinic visits. Here, we describe the rationale and design of a randomized, noninferiority trial designed to test the effectiveness and safety of using HIVST to support PrEP delivery in Kenya. METHODS: The JiPime-JiPrEP (Kiswahili for 'Test Yourself, PrEP Yourself') study is a three-arm randomized trial taking place in Thika, Kenya. Participants (n = 495) are eligible for enrollment if they are at least 18 years old, HIV-1 seronegative, and have been taking PrEP for 1 month. Three distinct participant types will be enrolled: men (n = 165) and women (n = 165) who are in mutually disclosed HIV-1 serodiscordant relationships, and women (n = 165) who are at HIV-1 risk and not in a known serodiscordant relationship. Participants in each of these subpopulations will be 1:1:1 randomized to: 1) the standard of care, with quarterly clinic visits; 2) oral HIVST, with biannual clinic visits plus oral HIVSTs to use at the quarters between those visits; or 3) blood-based HIVST, with biannual clinic visits plus blood-based HIVSTs. All participants will complete quantitative surveys and provide blood samples for the objective measurement of PrEP adherence at baseline, 6 months, and 12 months. The primary outcomes are PrEP adherence, PrEP continuation, and HIV-1 testing, measured at 6 months and secondarily at 12 months. DISCUSSION: The findings from this trial can help to understand how HIVST-a new HIV-1 testing technology-can support health systems in sub-Saharan Africa. Additionally, the findings can inform policy aimed at improving the efficiency of PrEP implementation and scale-up in Kenya. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03593629 . Retrospectively registered on 20 July 2018.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Anticorpos Anti-HIV/sangue , Infecções por HIV/prevenção & controle , HIV-1/imunologia , Profilaxia Pré-Exposição/métodos , Saliva/virologia , Autocuidado/métodos , Testes Sorológicos , Fármacos Anti-HIV/efeitos adversos , Feminino , Infecções por HIV/diagnóstico , Infecções por HIV/transmissão , Infecções por HIV/virologia , Humanos , Quênia , Masculino , Valor Preditivo dos Testes , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco , Fatores de Risco , Autocuidado/efeitos adversos , Parceiros Sexuais , Fatores de Tempo , Resultado do Tratamento
12.
Int J Cancer ; 145(9): 2468-2477, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31265124

RESUMO

Kaposi's sarcoma-associated herpesvirus (KSHV) and Epstein-Barr virus (EBV) are prevalent in sub-Saharan Africa, together with HIV; the consequent burden of disease is grave. The cofactors driving transmission of the two viruses and pathogenesis of associated malignancies are not well understood. We measured KSHV and EBV DNA in whole blood and saliva as well as serum antibodies levels in 175 Cameroonians with Kaposi's sarcoma and 1,002 age- and sex-matched controls with and without HIV. KSHV seroprevalence was very high (81%) in controls, while EBV seroprevalence was 100% overall. KSHV DNA was detectable in the blood of 36-46% of cases and 6-12% of controls; EBV DNA was detected in most participants (72-89%). In saliva, more cases (50-58%) than controls (25-28%) shed KSHV, regardless of HIV infection. EBV shedding was common (75-100%); more HIV+ than HIV- controls shed EBV. Cases had higher KSHV and EBV VL in blood and saliva then controls, only among HIV+ participants. KSHV and EBV VL were also higher in HIV+ than in HIV- controls. Cases (but not controls) were more likely to have detectable KSHV in blood if they also had EBV, whereas shedding of each virus in saliva was independent. While EBV VL in saliva and blood were modestly correlated, no correlation existed for KSHV. Numerous factors, several related to parasitic coinfections, were associated with detection of either virus or with VL. These findings may help better understand the interplay between the two gammaherpesviruses and generally among copathogens contributing to cancer burden in sub-Saharan Africa.


Assuntos
Infecções por HIV/sangue , Infecções por HIV/virologia , Herpesvirus Humano 4/patogenicidade , Herpesvirus Humano 8/patogenicidade , Saliva/virologia , Sarcoma de Kaposi/sangue , Sarcoma de Kaposi/virologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/sangue , Camarões , Estudos de Casos e Controles , Coinfecção/sangue , Coinfecção/virologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Adulto Jovem
13.
BMC Infect Dis ; 19(1): 632, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31315573

RESUMO

BACKGROUND: Hepatitis B virus (HBV) testing in oral fluid samples may provide advantages in diagnosis, screening or prevalence studies, especially among individuals with venous access difficulties. This study aims to optimize one commercially available assay for detecting total anti-HBc marker in oral fluid samples and to evaluate its utility under real life conditions in different settings for the purposes of prevalence and diagnostic studies. METHODS: Oral fluid was collected using a Salivette device and some parameters were initially evaluated: type of elution buffer and sample volume. Thereafter, the utility of oral fluid samples for detection of anti-HBc was evaluated in real life conditions in which, 1296 individuals gave serum and oral fluid samples. All serum samples were submitted to commercial EIAs to detect total anti-HBc, according to the manufacturer's instructions and oral fluid samples according to previous optimization. RESULTS: In optimization evaluation, PBS/BSA 0.5% and 100 µL of oral fluid (volume was two-fold increased compared to serum in EIA) were chosen as transport buffer and sample volume. In the field study, anti-HBc was detected in 211 out of 1296 serum samples giving overall oral fluid sensitivity of 52.6% and specificity of 96%. Concordance was higher in ambulatory setting (67.7) compared to general population (31.8). Mean ± standard deviation values of optical density/cutoff (OD/CO) in serum samples were higher in false-negative oral fluid samples than those seen in true positive samples. Sensitivity was higher in those presenting active infection compared to anti-HBc isolate and past infection. Sensitivity also increased in the ambulatory group when HCV individuals were excluded. CONCLUSIONS: It was possible to optimize a commercial EIA for detecting anti-HBc in oral fluid samples and where the highest concordance was found in ambulatory settings and among individuals with active infection.


Assuntos
Anticorpos Anti-Hepatite B/análise , Hepatite B/diagnóstico , Técnicas Imunoenzimáticas/métodos , Saliva/virologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
14.
Parasit Vectors ; 12(1): 363, 2019 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-31345269

RESUMO

BACKGROUND: Aedes caspius (Pallas, 1771) is a floodwater mosquito species widely distributed in the Western Palaearctic. As an anthropophilic species, its role as an arbovirus vector may be the key for understanding the transmission cycle of certain diseases in Europe such as Zika virus (ZIKV). Concerning vector competence for ZIKV, studies related to Ae. caspius are still scarce. ZIKV is an arbovirus that has provoked a widespread epidemic in the Pacific region (2007-2013) and in the Americas (2015-2016). ZIKV is associated with serious neurological injuries (e.g. microcephaly) and Guillain-Barré syndrome. Due to the ZIKV epidemics in the American continent, some viraemic travellers coming from endemic countries have been reported in Europe. More knowledge is therefore required to define the susceptibility of autochthonous mosquito species such as Ae. caspius for ZIKV in order to improve arbovirus surveillance and control programmes. In the present study, the vector competence of a European population of Ae. caspius was evaluated for two ZIKV lineages, the Suriname ZIKV strain (Asian lineage) and the MR766 ZIKV strain (African I lineage). Females were tested at 7, 14 and 21 days post-exposure (dpe) to infectious blood meals. An Ae. aegypti PAEA strain was used as a positive control. RESULTS: Aedes caspius presented low susceptibility to ZIKV infection and the virus was only detected by RT-qPCR in body samples. Low viral loads were detected for the MR766 strain at 7 dpe and for the Suriname strain at 14 and 21 dpe. Aedes caspius was unable to produce a disseminated infection and virus transmission at any of the tested time points. Using Ae. aegypti PAEA strain, infection, dissemination and transmission rates were calculated for the Suriname ZIKV strain (Asian lineage) at each time point. For the MR766 ZIKV strain (African I lineage), while only infection rates were estimated at each time point, no dissemination or transmission were detected in either species. CONCLUSIONS: The results of the present study reveal that the tested Ae. caspius population has a strong midgut escape barrier that limits the dissemination or transmission of the virus. As such, it seems unlikely that European Ae. caspius mosquitoes could be involved in ZIKV transmission if ZIKV was introduced into Europe. This information may help in designing a better strategy to European surveillance and control programmes for ZIKV.


Assuntos
Aedes/classificação , Aedes/virologia , Mosquitos Vetores/virologia , Infecção por Zika virus/transmissão , Animais , Europa (Continente) , Feminino , Saliva/virologia , Carga Viral , Zika virus
15.
Diagn Microbiol Infect Dis ; 95(2): 149-151, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31204109

RESUMO

We evaluated the performance of the OraQuick® HCV Rapid Antibody Test (Orasure Technologies, Inc., Bethlehem, PA) on oral fluid specimens when used by patients for self-testing. Participants used a set of instructions, self-collected their specimens, and interpreted their result. A researcher interpreted the test simultaneously and independently. Participants' true antibody status was determined by reviewing medical records or by a venipuncture blood sample. Sensitivity, specificity, and κ statistic were calculated. The sample included 95 participants (48 male and 47 female). Sensitivity and specificity on self-collected oral fluid samples were 88.4%% (95% CI, 74.9-96.1) and 100% (95% CI, 93-100), respectively, when patients interpreted the test results. Sensitivity and specificity were 97.7% (95% CI, 88-99.9) and 98% (95% CI, 89.6-100), respectively, when trained staff interpreted the result. κ statistic was 0.89 (95% CI 0.80-0.98). The rapid HCV test kit showed good performance when used for self-testing of oral fluid specimens.


Assuntos
Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/análise , Hepatite C/diagnóstico , Imunoensaio/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Hepacivirus/isolamento & purificação , Hepatite C/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Kit de Reagentes para Diagnóstico , Reprodutibilidade dos Testes , Saliva/imunologia , Saliva/virologia , Autocuidado , Sensibilidade e Especificidade , Manejo de Espécimes , Adulto Jovem
16.
Res Vet Sci ; 125: 113-118, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31181347

RESUMO

Oral fluid (n = 564) samples collected longitudinally from twelve 14-week-old pigs vaccinated with a porcine reproductive and respiratory syndrome virus (PRRSV) modified live vaccine were used to evaluate and compare the diagnostic performance of three commercial PRRSV oral fluid (OF) ELISAs (ELISAs 1, 2, 3). Serum samples (n = 132) tested by a PRRSV serum ELISA (ELISA 'S') provided an antibody response baseline for comparison. The initial analysis comparing the rate of positivity between each OF ELISA versus ELISA 'S' and then pairwise among the three OF ELISAs determined that ELISA 2 (143 false negative results) was significantly different from ELISAs 1 and 3, and from ELISA 'S' (Cochran's Q test, p < 0.05). Receiver operating characteristic (ROC) analyses based on the manufacturers' recommended cutoff were used to estimate the diagnostic sensitivities and specificities of ELISA 1 (100%, 100%), ELISA 2 (62%, 97%), and ELISA 3 (94%, 100%). As an additional aid for interpreting results, the diagnostic sensitivities and specificities of each OF ELISA were also estimated over a range of cutoffs. Area under the curve comparisons found no significant difference between ELISAs 1 and 3, but ELISA 2 differed from both ELISA 1 and 3 (ROC Chi-square, p < 0.05). Based on these analyses, the overall diagnostic performance of the three OF ELISAs ranked ELISA 1 ≥ ELISA 3 > ELISA 2.


Assuntos
Anticorpos Antivirais/isolamento & purificação , Ensaio de Imunoadsorção Enzimática/veterinária , Vírus da Síndrome Respiratória e Reprodutiva Suína/isolamento & purificação , Saliva/virologia , Animais , Ensaio de Imunoadsorção Enzimática/métodos , Síndrome Respiratória e Reprodutiva Suína/diagnóstico , Curva ROC , Sensibilidade e Especificidade , Soro/virologia , Suínos
17.
PLoS Negl Trop Dis ; 13(6): e0007433, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31188869

RESUMO

The importance of Zika virus (ZIKV) has increased noticeably since the outbreak in the Americas in 2015, when the illness was associated with congenital disorders. Although there is evidence of sexual transmission of the virus, the mosquito Aedes aegypti is believed to be the main vector for transmission to humans. This species of mosquito has not only been found naturally infected with ZIKV, but also has been the subject of study in many vector competence assays that employ different strains of ZIKV around the world. In Argentina, the first case was reported in February 2016 and a total of 278 autochthonous cases have since been confirmed, however, ZIKV virus has not been isolated from any mosquito species yet in Argentina. In order to elucidate if Argentinian Ae. aegypti populations could be a possible vector of ZIKV, we conducted vector competence studies that involved a local strain of ZIKV from Chaco province, and a Venezuelan strain obtained from an imported case. For this purpose, Ae. aegypti adults from the temperate area of Argentina (Buenos Aires province) were fed with infected blood. Body, legs and saliva were harvested and tested by plaque titration on plates of Vero cells for ZIKV at 7, 11 and 14 days post infection (DPI) in order to calculate infection, transmission, and dissemination rates, respectively. Both strains were able to infect mosquitoes at all DPIs, whereas dissemination and transmission were observed at all DPIs for the Argentinian strain but only at 14 DPI for the Venezuelan strain. This study proves the ability of Ae. aegypti mosquitoes from Argentina to become infected with two different strains of ZIKV, both belonging to the Asian lineage, and that the virus can disseminate to the legs and salivary glands.


Assuntos
Aedes/virologia , Mosquitos Vetores/virologia , Zika virus/crescimento & desenvolvimento , Estruturas Animais/virologia , Animais , Argentina , Feminino , Saliva/virologia , Carga Viral
18.
Int J Infect Dis ; 86: 31-39, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31207385

RESUMO

OBJECTIVES: Little is known about the birth prevalence and characteristics of congenital cytomegalovirus (CMV) infection in developing countries. To determine the prevalence and characteristics of congenital CMV infection in Indonesia, we conducted a prospective study in an urban birth cohort of neonates at a national referral hospital in 2016-2017, Jakarta, Indonesia. METHODS: Consecutively born neonates were screened for the presence of CMV by using pan-herpesvirus nested-PCR and Sanger sequencing in saliva and/or urine specimens. Both the neonatal clinical findings as well as maternal characteristics were also evaluated. RESULTS: From a total of 411 newborns screened, congenital CMV infection was confirmed in 5.8% of the neonates. These CMV-positive newborns were more likely to have ventriculomegaly and thrombocytopenia compared to CMV-negative neonates. Notably, 67% CMV-positive neonates in our study had clinical findings that required medical intervention, from which only nine presented with symptoms suggestive of congenital CMV infection. Furthermore, congenital CMV infected babies were almost four times more likely to be born to mothers that had placenta previa and placental abruption. CONCLUSIONS: Our work highlights the high prevalence of congenital CMV infection in neonates born in one of the biggest referral hospitals in metropolitan Jakarta, Indonesia.


Assuntos
Infecções por Citomegalovirus/virologia , Citomegalovirus/fisiologia , Doenças do Recém-Nascido/virologia , Adulto , Citomegalovirus/genética , Citomegalovirus/isolamento & purificação , Infecções por Citomegalovirus/congênito , Infecções por Citomegalovirus/epidemiologia , Feminino , Humanos , Indonésia/epidemiologia , Recém-Nascido , Doenças do Recém-Nascido/epidemiologia , Masculino , Reação em Cadeia da Polimerase , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Prevalência , Estudos Prospectivos , Saliva/virologia
19.
New Microbiol ; 42(3): 133-138, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31157397

RESUMO

The dental clinic is an appropriate place to promote the prevention of hepatitis C virus (HCV) infection and fast access for care of HCV-positive subjects with new-generation anti-HCV drugs. This study aimed to determine the socio-demographic profile of subjects screened for HCV virus in a dental clinic to acquire useful information for future campaigns of prevention. An easy, free-of-charge, screen salivary test was offered to patients referred to the dental clinic of San Raffaele Scientific Research Hospital in Milan, Italy for dental procedures. These patients were also asked to complete an anonymous questionnaire on demographics and risk behaviours. A total of 1388 of 2097 (66.19%) questionnaires were evaluable. The demographics of the population responding to this initiative was primarily Italians citizen (96.47%), homogeneous gender distribution (55.55%), age over 50 (609 subjects; 43.88%), with high-level education and stable professional positions. 905 subjects (65.20%) were never tested for HCV before. The test showed positive reactivity in 22 cases (1.05%); of these, 21 subjects were known to be HCV-positive, and the test confirmed their status. One subject was newly diagnosed as HCV-positive. The percentage of subjects who were never tested for HCV infection appears too high (905 subjects, i.e., 65.20%), especially among subjects with high level of education and professions, and among adults over 40 or young people (18-25). The easy screening test in dental clinic can help raise awareness, promote early diagnosis and prevention, and provide a fast link to care for HCV infection.


Assuntos
Clínicas Odontológicas , Hepacivirus , Anticorpos Anti-Hepatite C , Testes Imediatos , Saliva/virologia , Adolescente , Adulto , Demografia , Feminino , Hepatite C/diagnóstico , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Testes Imediatos/normas , Gravidez , Adulto Jovem
20.
Insect Biochem Mol Biol ; 111: 103169, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31103782

RESUMO

The yellow fever mosquito, Aedes aegypti, serves as the primary vector for epidemic transmission of yellow fever, dengue, Zika (ZIKV), and chikungunya viruses to humans. Control of Ae. aegypti is currently limited to insecticide applications and larval habitat management; however, to combat growing challenges with insecticide resistance, novel genetic approaches for vector population reduction or transmission interruption are being aggressively pursued. The objectives of this study were to assess the ability of the Ae. aegypti antiviral exogenous-small interfering RNA (exo-siRNA) response to inhibit ZIKV infection and transmission, and to identify the optimal RNA interference (RNAi) target region in the ZIKV genome. We accomplished these objectives by in vitro transcription of five long double-stranded RNAs (dsRNAs) from the genome region spanning the NS2B-NS3-NS4A genes, which were the most highly conserved among ZIKV RNA sequences representing both East and West African and Asian-American clades, and evaluation of the ability of these dsRNAs to trigger an effective antiviral exo-siRNA response after intrathoracic injection into Ae. aegypti. In a pilot study, five ZIKV dsRNAs were tested by intrathoracic inoculation of 250 ng dsRNA into groups of approximately 5-day-old mosquitoes. Three days post-inoculation, mosquitoes were provided an infectious blood-meal containing ZIKV strain PRVABC59 (Puerto Rico), MR766 (Uganda), or 41525 (Senegal). On days 7 and 14 post-infection individual whole mosquito bodies were assessed for ZIKV infectious titer by plaque assays. Based on the results of this initial assessment, three dsRNAs were selected for further evaluation of viral loads of matched body and saliva expectorants using a standardized infectious dose of 1 × 107 PFU/mL of each ZIKV strain. Fourteen days post-exposure to ZIKV, paired saliva and carcass samples were harvested from individual mosquitoes and assessed for ZIKV RNA load by qRT-PCR. Injection of each of the three dsRNAs resulted in significant inhibition of replication of all three strains of ZIKV in mosquito bodies and saliva. This study lays critical groundwork for pursuing ZIKV transmission-blocking strategies that exploit the Ae. aegypti exo-siRNA response for arbovirus suppression in natural populations.


Assuntos
Aedes/virologia , Interferência de RNA , Infecção por Zika virus/transmissão , Zika virus/genética , Animais , Bovinos , Mosquitos Vetores/virologia , Projetos Piloto , RNA de Cadeia Dupla , RNA Interferente Pequeno , Saliva/virologia , Análise de Sequência de RNA , Células Vero , Carga Viral , Replicação Viral , Zika virus/fisiologia , Infecção por Zika virus/virologia
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