RESUMO
OBJECTIVES: This review article summarizes what has been published on Alkhumra hemorrhagic fever virus (AHFV), a novel flavivirus that was discovered in Saudi Arabia in 1995. METHODS: PubMed was used to search for studies published from January 1995 to June 2019 using the key words Alkhumra virus, Alkhurma virus, novel flavivirus, and tick-borne encephalitis virus. Additionally, records of the Saudi Ministry of Health were reviewed. RESULTS: Thirty-two articles on AHFV were identified. Acute febrile flu-like illness, hepatitis, hemorrhagic manifestations, and, less commonly, encephalitis are the main clinical features. The virus seems to be transmitted from livestock animals to humans by direct contact with these animals or their raw meat, or perhaps by tick or mosquito bites. The ability of ticks and mosquitoes to serve as vectors for AHFV needs to be confirmed by biological studies. The exact role of animals such as sheep, goats, camels, and other mammals in the transmission and maintenance of the virus remains to be elucidated. Preventive measures require an interdisciplinary approach involving the human and veterinary health sectors, the municipality, the ministry of agriculture, the vector control sector, and academic and research institutes. CONCLUSIONS: AHFV has been well characterized; nevertheless, some aspects remain to be elucidated.
Assuntos
Vírus da Encefalite Transmitidos por Carrapatos , Encefalite Transmitida por Carrapatos , Animais , Anticorpos Antivirais , Bases de Dados Factuais , Vírus da Encefalite Transmitidos por Carrapatos/classificação , Encefalite Transmitida por Carrapatos/diagnóstico , Encefalite Transmitida por Carrapatos/epidemiologia , Encefalite Transmitida por Carrapatos/transmissão , Encefalite Transmitida por Carrapatos/virologia , Humanos , Filogenia , Arábia Saudita , Doenças Transmitidas por Carrapatos/prevenção & controle , Doenças Transmitidas por Carrapatos/transmissão , Doenças Transmitidas por Vetores/prevenção & controle , Doenças Transmitidas por Vetores/transmissãoRESUMO
Extracellular vesicles (EVs) carry important biomolecules, including metabolites, and contribute to the spread and pathogenesis of some viruses. However, to date, limited data are available on EV metabolite content that might play a crucial role during infection with the SARS-CoV-2 virus. Therefore, this study aimed to perform untargeted metabolomics to identify key metabolites and associated pathways that are present in EVs, isolated from the serum of COVID-19 patients. The results showed the presence of antivirals and antibiotics such as Foscarnet, Indinavir, and lymecycline in EVs from patients treated with these drugs. Moreover, increased levels of anti-inflammatory metabolites such as LysoPS, 7-α,25-Dihydroxycholesterol, and 15-d-PGJ2 were detected in EVs from COVID-19 patients when compared with controls. Further, we found decreased levels of metabolites associated with coagulation, such as thromboxane and elaidic acid, in EVs from COVID-19 patients. These findings suggest that EVs not only carry active drug molecules but also anti-inflammatory metabolites, clearly suggesting that exosomes might play a crucial role in negotiating with heightened inflammation during COVID-19 infection. These preliminary results could also pave the way for the identification of novel metabolites that might act as critical regulators of inflammatory pathways during viral infections.
Assuntos
COVID-19/metabolismo , Vesículas Extracelulares/metabolismo , Metaboloma , SARS-CoV-2/fisiologia , Adulto , Anti-Inflamatórios/metabolismo , COVID-19/patologia , Vesículas Extracelulares/patologia , Feminino , Humanos , Masculino , Metabolômica , Pessoa de Meia-IdadeRESUMO
BACKGROUND: A marked increase in the number of cases of Middle East respiratory syndrome coronavirus (MERS-CoV) infection occurred in Jeddah, Saudi Arabia, in early 2014. We evaluated patients with MERS-CoV infection in Jeddah to explore reasons for this increase and to assess the epidemiologic and clinical features of this disease. METHODS: We identified all cases of laboratory-confirmed MERS-CoV infection in Jeddah that were reported to the Saudi Arabian Ministry of Health from January 1 through May 16, 2014. We conducted telephone interviews with symptomatic patients who were not health care personnel, and we reviewed hospital records. We identified patients who were reported as being asymptomatic and interviewed them regarding a history of symptoms in the month before testing. Descriptive analyses were performed. RESULTS: Of 255 patients with laboratory-confirmed MERS-CoV infection, 93 died (case fatality rate, 36.5%). The median age of all patients was 45 years (interquartile range, 30 to 59), and 174 patients (68.2%) were male. A total of 64 patients (25.1%) were reported to be asymptomatic. Of the 191 symptomatic patients, 40 (20.9%) were health care personnel. Among the 151 symptomatic patients who were not health care personnel, 112 (74.2%) had data that could be assessed, and 109 (97.3%) of these patients had had contact with a health care facility, a person with a confirmed case of MERS-CoV infection, or someone with severe respiratory illness in the 14 days before the onset of illness. The remaining 3 patients (2.7%) reported no such contacts. Of the 64 patients who had been reported as asymptomatic, 33 (52%) were interviewed, and 26 of these 33 (79%) reported at least one symptom that was consistent with a viral respiratory illness. CONCLUSIONS: The majority of patients in the Jeddah MERS-CoV outbreak had contact with a health care facility, other patients, or both. This highlights the role of health care-associated transmission. (Supported by the Ministry of Health, Saudi Arabia, and by the U.S. Centers for Disease Control and Prevention.).
Assuntos
Infecções por Coronavirus/transmissão , Surtos de Doenças , Transmissão de Doença Infecciosa do Profissional para o Paciente , Coronavírus da Síndrome Respiratória do Oriente Médio , Adulto , Idoso , Infecções por Coronavirus/epidemiologia , Infecção Hospitalar/epidemiologia , Feminino , Humanos , Controle de Infecções , Masculino , Pessoa de Meia-Idade , Arábia Saudita/epidemiologiaRESUMO
We describe the isolation and sequencing of Middle East respiratory syndrome coronavirus (MERS-CoV) obtained from a dromedary camel and from a patient who died of laboratory-confirmed MERS-CoV infection after close contact with camels that had rhinorrhea. Nasal swabs collected from the patient and from one of his nine camels were positive for MERS-CoV RNA. In addition, MERS-CoV was isolated from the patient and the camel. The full genome sequences of the two isolates were identical. Serologic data indicated that MERS-CoV was circulating in the camels but not in the patient before the human infection occurred. These data suggest that this fatal case of human MERS-CoV infection was transmitted through close contact with an infected camel.
Assuntos
Camelus/virologia , Infecções por Coronavirus/transmissão , Coronavirus/isolamento & purificação , Nariz/virologia , Adulto , Animais , Coronavirus/genética , Genoma Viral , Humanos , Masculino , Oriente Médio , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Arábia Saudita , Zoonoses/transmissãoRESUMO
Risk factors for human-to-human transmission of Middle East respiratory syndrome coronavirus (MERS-CoV) are largely unknown. After MERS-CoV infections occurred in an extended family in Saudi Arabia in 2014, relatives were tested by using real-time reverse transcription PCR (rRT-PCR) and serologic methods. Among 79 relatives, 19 (24%) were MERS-CoV positive; 11 were hospitalized, and 2 died. Eleven (58%) tested positive by rRT-PCR; 8 (42%) tested negative by rRT-PCR but positive by serology. Compared with MERS-CoV-negative adult relatives, MERS-CoV-positive adult relatives were older and more likely to be male and to have chronic medical conditions. Risk factors for household transmission included sleeping in an index patient's room and touching respiratory secretions from an index patient. Casual contact and simple proximity were not associated with transmission. Serology was more sensitive than standard rRT-PCR for identifying infected relatives, highlighting the value of including serology in future investigations.
Assuntos
Busca de Comunicante , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Família , Coronavírus da Síndrome Respiratória do Oriente Médio/isolamento & purificação , Adolescente , Adulto , Anticorpos Antivirais/sangue , Infecções por Coronavirus/epidemiologia , Feminino , Humanos , Masculino , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Risco , Arábia Saudita/epidemiologia , Testes SorológicosRESUMO
During March-May 2014, a Middle East respiratory syndrome (MERS) outbreak occurred in Jeddah, Saudi Arabia, that included many persons who worked or received medical treatment at King Fahd General Hospital. We investigated 78 persons who had laboratory-confirmed MERS during March 2-May 10 and documented contact at this hospital. The 78 persons with MERS comprised 53 patients, 16 healthcare workers, and 9 visitors. Among the 53 patients, the most probable sites of acquisition were the emergency department (22 patients), inpatient areas (17), dialysis unit (11), and outpatient areas (3). Infection control deficiencies included limited separation of suspected MERS patients, patient crowding, and inconsistent use of infection control precautions; aggressive improvements in these deficiencies preceded a decline in cases. MERS coronavirus transmission probably was multifocal, occurring in multiple hospital settings. Continued vigilance and strict application of infection control precautions are necessary to prevent future MERS outbreaks.
Assuntos
Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Infecção Hospitalar , Surtos de Doenças , Coronavírus da Síndrome Respiratória do Oriente Médio , Centros de Atenção Terciária , Adulto , Idoso , Estudos de Coortes , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/tratamento farmacológico , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Arábia Saudita/epidemiologiaRESUMO
Healthcare settings can amplify transmission of Middle East respiratory syndrome coronavirus (MERS-CoV), but knowledge gaps about the epidemiology of transmission remain. We conducted a retrospective cohort study among healthcare personnel in hospital units that treated MERS-CoV patients. Participants were interviewed about exposures to MERS-CoV patients, use of personal protective equipment, and signs and symptoms of illness after exposure. Infection status was determined by the presence of antibodies against MERS-CoV. To assess risk factors, we compared infected and uninfected participants. Healthcare personnel caring for MERS-CoV patients were at high risk for infection, but infection most often resulted in a relatively mild illness that might be unrecognized. In the healthcare personnel cohort reported here, infections occurred exclusively among those who had close contact with MERS-CoV patients.
Assuntos
Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Pessoal de Saúde , Coronavírus da Síndrome Respiratória do Oriente Médio , Adolescente , Adulto , Idoso , Infecções por Coronavirus/virologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Fatores de Risco , Arábia Saudita/epidemiologia , Estudos Soroepidemiológicos , Adulto JovemRESUMO
Risk factors for primary Middle East respiratory syndrome coronavirus (MERS-CoV) illness in humans are incompletely understood. We identified all primary MERS-CoV cases reported in Saudi Arabia during March-November 2014 by excluding those with history of exposure to other cases of MERS-CoV or acute respiratory illness of unknown cause or exposure to healthcare settings within 14 days before illness onset. Using a case-control design, we assessed differences in underlying medical conditions and environmental exposures among primary case-patients and 2-4 controls matched by age, sex, and neighborhood. Using multivariable analysis, we found that direct exposure to dromedary camels during the 2 weeks before illness onset, as well as diabetes mellitus, heart disease, and smoking, were each independently associated with MERS-CoV illness. Further investigation is needed to better understand animal-to-human transmission of MERS-CoV.
Assuntos
Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/etiologia , Coronavírus da Síndrome Respiratória do Oriente Médio/patogenicidade , Adulto , Idoso , Animais , Camelus/virologia , Estudos de Casos e Controles , Infecções por Coronavirus/virologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Arábia Saudita/epidemiologia , Adulto JovemRESUMO
Middle East respiratory syndrome coronavirus (MERS-CoV) causes a spectrum of illness. We evaluated whether cycle threshold (Ct) values (which are inversely related to virus load) were associated with clinical severity in patients from Saudi Arabia whose nasopharyngeal specimens tested positive for this virus by real-time reverse transcription PCR. Among 102 patients, median Ct of 31.0 for the upstream of the E gene target for 41 (40%) patients who died was significantly lower than the median of 33.0 for 61 survivors (p=0.0087). In multivariable regression analyses, risk factors for death were age>60 years), underlying illness, and decreasing Ct for each 1-point decrease in Ct). Results were similar for a composite severe outcome (death and/or intensive care unit admission). More data are needed to determine whether modulation of virus load by therapeutic agents affects clinical outcomes.
Assuntos
Infecções por Coronavirus/mortalidade , Coronavirus/genética , Adolescente , Adulto , Idoso , Criança , Coronavirus/imunologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Arábia Saudita/epidemiologiaRESUMO
BACKGROUND: Dengue viruses (DENVs) are mosquito-borne viruses which can cause disease ranging from mild fever to severe dengue infection. These viruses are endemic in several tropical and subtropical regions. Multiple outbreaks of DENV serotypes 1, 2 and 3 (DENV-1, DENV-2 and DENV-3) have been reported from the western region in Saudi Arabia since 1994. Strains from at least two genotypes of DENV-1 (Asia and America/Africa genotypes) have been circulating in western Saudi Arabia until 2006. However, all previous studies reported from Saudi Arabia were based on partial sequencing data of the envelope (E) gene without any reports of full genome sequences for any DENV serotypes circulating in Saudi Arabia. FINDINGS: Here, we report the isolation and the first complete genome sequence of a DENV-1 strain (DENV-1-Jeddah-1-2011) isolated from a patient from Jeddah, Saudi Arabia in 2011. Whole genome sequence alignment and phylogenetic analysis showed high similarity between DENV-1-Jeddah-1-2011 strain and D1/H/IMTSSA/98/606 isolate (Asian genotype) reported from Djibouti in 1998. Further analysis of the full envelope gene revealed a close relationship between DENV-1-Jeddah-1-2011 strain and isolates reported between 2004-2006 from Jeddah as well as recent isolates from Somalia, suggesting the widespread of the Asian genotype in this region. CONCLUSIONS: These data suggest that strains belonging to the Asian genotype might have been introduced into Saudi Arabia long before 2004 most probably by African pilgrims and continued to circulate in western Saudi Arabia at least until 2011. Most importantly, these results indicate that pilgrims from dengue endemic regions can play an important role in the spread of new DENVs in Saudi Arabia and the rest of the world. Therefore, availability of complete genome sequences would serve as a reference for future epidemiological studies of DENV-1 viruses.
Assuntos
Vírus da Dengue/classificação , Vírus da Dengue/genética , Genoma Viral , RNA Viral/genética , Análise de Sequência de DNA , Adulto , Animais , Dengue/epidemiologia , Dengue/transmissão , Dengue/virologia , Vírus da Dengue/isolamento & purificação , Feminino , Humanos , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia , Arábia Saudita/epidemiologia , Homologia de SequênciaRESUMO
Alkhumra hemorrhagic fever virus (AHFV) is an emerging flavivirus that was isolated originally from Saudi Arabia in 1994-1995. The main tests used for the detection of AHFV are the real time (rt) RT-PCR and virus isolation in cell culture. In the present study the detection of AHFV by rtRT-PCR was compared with virus isolation in BHK-21, HEp-2, and LLC-MK2 cell lines. AHFV suspensions grown in BHK-21, HEp-2, and LLC-MK2 cell lines were serially diluted 10-fold from 10(-1) to 10(-11) . Samples from each dilution were used to inoculate four cell culture tubes and were also examined by the rtRT-PCR for AHFV RNA. Fifteen non-inoculated cell culture samples (five from each cell line) were included blindly in both tests. Thus, a total of 132 AHFV-positive and 15 negative control samples were tested. The rtRT-PCR could detect the viral RNA in all diluted specimens up to and including the 10(-10) dilution (40 specimens for each cell line), whereas, cell cultures were positive in 70% of specimens for BHK-21, 65% for LLC-MK2, and 45% for HEp-2 at this dilution. None of the three cell cultures nor the rtRT-PCR was positive at 10(-11) dilution. The specificity and positive predictive values of virus isolation compared to rtRT-PCR were each 100%, whereas the negative predictive values were 29.4% for BHK-21, 26.3% for LLC-MK2, and 18.5% for HEp-2. In conclusion, the rtRT-PCR is more sensitive than virus isolation for detecting AHFV.
Assuntos
Técnicas de Laboratório Clínico/métodos , Vírus da Encefalite Transmitidos por Carrapatos/isolamento & purificação , Encefalite Transmitida por Carrapatos/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Animais , Linhagem Celular , Vírus da Encefalite Transmitidos por Carrapatos/genética , Vírus da Encefalite Transmitidos por Carrapatos/crescimento & desenvolvimento , Humanos , Valor Preditivo dos Testes , Arábia Saudita , Sensibilidade e Especificidade , Cultura de Vírus/métodosRESUMO
BACKGROUND: Alkhumra hemorrhagic fever virus (AHFV) is a newly described flavivirus first isolated in 1994-1995 from the Alkhumra district south of Jeddah, Saudi Arabia. Subsequently, the virus was also isolated from Makkah (2001-2003) and Najran (2008-2009), Saudi Arabia. METHODS: The full-length genome of an AHFV strain isolated from patients in Najran (referred to as AHFV/997/NJ/09/SA) was PCR amplified and sequenced, and compared with the sequences of 18 other AHFV strains previously isolated from Jeddah and Makkah, dengue virus (DENV), Kyasanur forest disease virus (KFDV), Langat virus, Omsk hemorrhagic fever virus (OHFV), and tick-borne encephalitis virus (TBEV). RESULTS: The RNA of the AHFV/997/NJ/09/SA strain was found to have 10,546 nucleotides encoding for a single 3,416-amino acid polyprotein, whereas the previously reported AHFV strains were composed of 10,685-10,749 nucleotides. The AHFV/997/NJ/09/SA strain showed about 99% homology with the previously reported AHFV strains. The KFDV, Langat virus, TBEV, and OHFV isolates formed a separate cluster with a variable homology. The most important variations were observed in the core protein and NS4a gene sequences of two AHFV isolates. CONCLUSION: The variation in the number of nucleotides and phylogenetic analysis with the other AHFV isolates could have resulted from recombination of circulating virus strains.
Assuntos
Vírus da Encefalite Transmitidos por Carrapatos/genética , Encefalite Transmitida por Carrapatos/virologia , Genoma Viral , RNA Viral/genética , Análise de Sequência de DNA , Análise por Conglomerados , Vírus da Encefalite Transmitidos por Carrapatos/isolamento & purificação , Humanos , Filogenia , Poliproteínas/genética , Arábia Saudita , Homologia de SequênciaRESUMO
OBJECTIVE: The purpose of this study was to describe the chest CT findings in seven patients with Middle East respiratory syndrome coronavirus (MERS-CoV) infection. CONCLUSION: The most common CT finding in hospitalized patients with MERS-CoV infection is that of bilateral predominantly subpleural and basilar airspace changes, with more extensive ground-glass opacities than consolidation. The subpleural and peribronchovascular predilection of the abnormalities is suggestive of an organizing pneumonia pattern.
Assuntos
Pulmão/diagnóstico por imagem , Radiografia Torácica/métodos , Síndrome Respiratória Aguda Grave/classificação , Síndrome Respiratória Aguda Grave/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Egito , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Estudos Retrospectivos , Arábia Saudita , Adulto JovemRESUMO
The physico-chemical and biological characteristics of Alkhumra hemorrhagic fever virus (AHFV) are not yet known. The present study describes the thermal stability of this virus at different temperatures for different periods. The kinetics of thermal inactivation were studied, linear regressions were plotted, the Arrhenius equation was applied, and the activation energy was calculated accordingly. Titers of the residual virus were determined in median tissue culture infective dose (TCID50), and the rate of destruction of infectivity at various temperatures was determined. Infectivity of AHFV was completely lost upon heating for 3 minutes at 60 °C and for 30 min at 56 °C. However, the virus could maintain 33.2 % of its titer after heating for 60 min at 45 °C and 32 % of its titer after heating for 60 min at 50 °C. In conclusion, AHFV is thermo-labile, and its inactivation follows first-order kinetics.
Assuntos
Vírus da Encefalite Transmitidos por Carrapatos/isolamento & purificação , Vírus da Encefalite Transmitidos por Carrapatos/fisiologia , Temperatura Alta , Inativação de Vírus , Animais , Linhagem Celular , Chlorocebus aethiops , Vírus da Encefalite Transmitidos por Carrapatos/patogenicidade , HumanosRESUMO
The use of tenofovir disoproxil fumarate (TDF) as an antiretroviral agent has been reported to adversely affect both renal tubules and bone health, leading to pathological fractures. While such an effect is largely reversible, substituting TDF with tenofovir alafenamide (TAF) might result in lower rates of adverse events with the preservation of tenofovir effectiveness. We report a case of a 40-year-old lady with HIV infection who had a vertebral fragility fracture secondary to TDF-associated Fanconi syndrome. The syndrome developed four years after TDF cessation and switching to TAF. Other etiologies for decreased bone mass were excluded, and the diagnosis of Fanconi syndrome was established based on her bone mineral density (BMD) and urine parameters. She was treated conservatively with active vitamin D, calcium, and progesterone/estrogen combination, but her phosphate wasting persisted despite switching to TAF; this likely represents a delayed irreversible effect of TDF on the patient's bone remodeling. This case report highlights the chronic sequelae of TDF therapy and the importance of monitoring for and early detection of renal tubulopathy and osteoporotic fractures in this patient population.
RESUMO
BACKGROUND: The objective of this study was to describe the prevalence, characteristics, and risk factors of coronavirus disease-2019 (COVID-19) infection among health care workers (HCWs) at King Abdulaziz University Hospital, Jeddah, Saudi Arabia. METHODS: A prospective cross-sectional study of HCWs confirmed to have COVID-19 infection from March 1, 2020 to December 31, 2022. RESULTS: A total of 746 HCWs were diagnosed with COVID-19. Patients' age ranged from 22 to 60 years with a mean ± standard deviation of 37.4 ± 8.7 years. The infection was community-acquired in 584 (78.3%) HCWs. The vast majority (82.6%) of the infected HCWs had no comorbidities. Nurses (400/746 or 53.6%) represented the largest professional group, followed by physicians (128/746 or 17.2%), administrative staff (125/746 or 16.8%), respiratory therapists (54/746 or 7.2%), and physiotherapists (39/746 or 5.2%). Symptoms included fever (64.1%), cough (55.6%), sore throat (44.6%), headache (22.9%), runny nose (19.6%), shortness of breath (19.0%), fatigue (12.7%), body aches (11.4%), diarrhea (10.9%), vomiting (4.4%), and abdominal pain (2.8%). Most (647 or 86.7%) patients were managed as outpatients. Four (0.5%) HCWs died. CONCLUSIONS: HCWs face a dual risk of SARS-CoV-2 infection, both from community exposure and within the hospital setting. Comprehensive infection control strategies are needed to protect HCWs both inside and outside the hospital environment.
RESUMO
Alkhumra hemorrhagic fever virus (AHFV) is an emerging flavivirus that was discovered in 1994-1995 in Saudi Arabia. Clinical manifestations of AHFV infection include hemorrhagic fever, hepatitis, and encephalitis, with a reported mortality rate as high as 25 %. Biological characteristics of this virus have not been well defined. Agglutination of erythrocytes (hemagglutination) is a laboratory tool for studying the attachment of viruses to cellular receptors. The envelope protein contains sites for attachment to host receptors to initiate the process of infection and is thus an essential component of the virion. In the present study, we examined the ability of AHFV to agglutinate erythrocytes of 13 mammalian and avian species (human group O+, camel, cow, sheep, goat, rabbit, guinea pig, mouse, rat, chicken, duck, goose and turkey) with and without trypsin-treatment. Without trypsin treatment, AHFV failed to agglutinate erythrocytes of all examined species. Following trypsin treatment, AHFV agglutinated erythrocytes of five species, namely, goose, human group O+, rat, guinea pig, and mouse, in descending order of sensitivity. This trypsin-dependent hemagglutination test has potential for use in serological and functional studies of AHFV.
Assuntos
Eritrócitos/virologia , Infecções por Flavivirus/virologia , Flavivirus/fisiologia , Tripsina/metabolismo , Animais , Aves , Bovinos , Galinhas , Eritrócitos/imunologia , Flavivirus/imunologia , Gansos , Cobaias , Testes de Hemaglutinação , Humanos , Camundongos , Coelhos , Ratos , Ovinos , Ligação ViralRESUMO
BACKGROUND: Investigations were conducted by the authors to explore an outbreak of viral hemorrhagic fever (VHF) reported in 2010 from Al-Mukalla city, the capital of Hadramout in Yemen. METHODS: From 15-17 June 2010, the outbreak investigation period, specimens were obtained within 7 days after onset of illness of 18 acutely ill patients hospitalized with VHF and 15 household asymptomatic contacts of 6 acute cases. Additionally, 189 stored sera taken from acutely ill patients with suspected VHF hospitalized in the preceding 12 months were obtained from the Ministry of Health of Yemen. Thus, a total of 222 human specimens were collected; 207 specimens from acute cases and 15 specimens from contacts. All samples were tested with RT-PCR for dengue (DENV), Alkhumra (ALKV), Rift Valley Fever (RVFV), Yellow Fever (YFV), and Chikungunya (CHIKV) viruses. Samples were also tested for DENV IgM, IgG, and NS1-antigen. Medical records of patients were reviewed and demographic, clinical, and laboratory data was collected. RESULTS: Of 207 patients tested, 181 (87.4%) patients were confirmed to have acute dengue with positive dengue NS1-antigen (97 patients, 46.9%) and/or IgM (163 patients, 78.7%). Of the 181 patients with confirmed dengue, 100 (55.2%) patients were IgG-positive. DENV RNA was detected in 2 (1%) patients with acute symptoms; both samples were molecularly typed as DENV type 3. No other VHF viruses were detected. For the 15 contacts tested, RT-PCR tests for the five viruses were negative, one contact was dengue IgM positive, and another one was dengue IgG positive. Of the 181 confirmed dengue patients, 120 (66.3%) patients were males and the median age was 24 years. The most common manifestations included fever (100%), headache (94.5%), backache (93.4%), malaise (88.4%), arthralgia (85.1%), myalgia (82.3%), bone pain (77.9%), and leukopenia (76.2%). Two (1.1%) patients died. CONCLUSIONS: DENV-3 was confirmed to be the cause of an outbreak of VHF in Al-Mukalla. It is important to use both IgM and NS1-antigen tests to confirm acute dengue particularly under the adverse field conditions, where proper storage and transportation of specimens are missing, which substantially reduce the sensitivity of the RT-PCR for detecting DENV RNA.
Assuntos
Vírus da Dengue/isolamento & purificação , Surtos de Doenças , Dengue Grave/epidemiologia , Dengue Grave/virologia , Adolescente , Adulto , Idoso , Animais , Anticorpos Antivirais/sangue , Criança , Pré-Escolar , Estudos de Coortes , Vírus da Dengue/genética , Feminino , Doenças das Cabras/epidemiologia , Doenças das Cabras/virologia , Cabras , Humanos , Masculino , Pessoa de Meia-Idade , RNA Viral/análise , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Dengue Grave/diagnóstico , Ovinos , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/virologia , Iêmen/epidemiologia , Zoonoses/epidemiologia , Zoonoses/virologiaRESUMO
The coronavirus disease 2019 (COVID-19) pandemic is challenging healthcare systems worldwide. The prediction of disease prognosis has a critical role in confronting the burden of COVID-19. We aimed to investigate the feasibility of predicting COVID-19 patient outcomes and disease severity based on clinical and hematological parameters using machine learning techniques. This multicenter retrospective study analyzed records of 485 patients with COVID-19, including demographic information, symptoms, hematological variables, treatment information, and clinical outcomes. Different machine learning approaches, including random forest, multilayer perceptron, and support vector machine, were examined in this study. All models showed a comparable performance, yielding the best area under the curve of 0.96, in predicting the severity of disease and clinical outcome. We also identified the most relevant features in predicting COVID-19 patient outcomes, and we concluded that hematological parameters (neutrophils, lymphocytes, D-dimer, and monocytes) are the most predictive features of severity and patient outcome.