A meta-analysis of Chikungunya virus in neurological disorders.

Chikungunya disease typically presents with the fever-arthralgia-rash symptom triad. However, an increase in the number of atypical clinical manifestations, particularly neurological disorders, has occurred. The current evidence regarding the pooled prevalence of Chikungunya virus (CHIKV)-associated neurological cases (CANCs) suspected of having an arboviral aetiology is not well-understood. Therefore, this meta-analysis included 19 studies (n = 7319 patients) and aimed to determine the pooled rate of exposure to CANC. The pooled positivity rate of CANC was 12 % (95 % CI: 6-19), and Brazil was overrepresented (11/19). These estimations varied between 3 and 14 % based on the diagnostic method (real-time PCR vs. ELISA-IgM) and biological samples (cerebrospinal fluid or blood specimens) used for detection of CHIKV. Regarding the frequency of CHIKV in neurological clinical subgroups, the rates were higher among patients with myelitis (27 %), acute disseminated encephalomyelitis (27 %), Guillain-Barré syndrome (15 %), encephalitis (12 %), and meningoencephalitis (7 %). Our analysis highlights the significant burden of CANC. However, the data must be interpreted with caution due to the heterogeneity of the results, which may be related to the location of the studies covering endemic periods and/or outbreaks of CHIKV. Current surveillance resources should also focus on better characterizing the epidemiology of CHIKV infection in neurological disorders. Additionally, future studies should investigate the interactions between CHIKV and neurological diseases with the aim of gaining deeper insight into the mechanisms underlying the cause-and-effect relationship between these two phenomena.

The Emergence of the New P.4 Lineage of SARS-CoV-2 With Spike L452R Mutation in Brazil.

The emergence of several SARS-CoV-2 lineages presenting adaptive mutations is a matter of concern worldwide due to their potential ability to increase transmission and/or evade the immune response. While performing epidemiological and genomic surveillance of SARS-CoV-2 in samples from Porto Ferreira-São Paulo-Brazil, we identified sequences classified by pangolin as B.1.1.28 harboring Spike L452R mutation, in the RBD region. Phylogenetic analysis revealed that these sequences grouped into a monophyletic branch, with others from Brazil, mainly from the state of São Paulo. The sequences had a set of 15 clade defining amino acid mutations, of which six were in the Spike protein. A new lineage was proposed to Pango and it was accepted and designated P.4. In samples from the city of Porto Ferreira, P.4 lineage has been increasing in frequency since it was first detected in March 2021, corresponding to 34.7% of the samples sequenced in June, the second in prevalence after P.1. Also, it is circulating in 30 cities from the state of São Paulo, and it was also detected in one sample from the state of Sergipe and two from the state of Rio de Janeiro. Further studies are needed to understand whether P.4 should be considered a new threat.

Synthesis, characterization, and evaluation of antibacterial activity of transition metal oxyde nanoparticles.

Nanoparticles (NPs) have a wide range of applications in various areas. For health application, cytotoxicity tests are used to ensure its efficiency and safety. In this paper, ZnFe2O4, CoFe2O4, Zn0.5Co0.5Fe2O4 NPs were synthesized, characterized and their antibacterial properties were evaluated. The Sol-Gel method was used to synthesize the NPs. Their electronic and crystallographic structures were characterized by Fourier Transform Infrared Spectroscopy Analysis (FTIR), X-ray fluorescence (XRF), X-Ray Diffraction (XRD), and Transmission Electron Microscopy (TEM). To perform the antibacterial evaluation, ferrites were dispersed through nanoemulsion to prevent the crystals from accumulating together. Then the evaluation was performed through microdilution in a 96-well plate and diffusion in agar disc in contact with 3 different strains of Staphylococcus aureus and Escherichia coli. It demonstrated that the Sol-Gel method was efficient to synthesize NPs with suitable sizes for health application. All synthesized NPs showed the inhibition of bacterias with different concentrations used.

Detection of Rocio Virus SPH 34675 during Dengue Epidemics, Brazil, 2011-2013.

Recent seroprevalence studies in animals detected Rocio virus in regions of Brazil, indicating risk for re-emergence of this pathogen. We identified Rocio virus RNA in samples from 2 human patients for whom dengue fever was clinically suspected but ruled out by laboratory findings. Testing for infrequent flavivirus infections should expedite diagnoses.

Evidence based on a meta-analysis of human cytomegalovirus infection in glioma.

Malignant gliomas are the most common types of incurable primary brain tumours. Therefore, to better clarify the aetiology and pathogenesis of the disease and analyse the risk factors involved, several researchers have highlighted a possible link to human cytomegalovirus (HCMV). Regarding this potential link, the numbers of studies and controversies concerning the relationship between HCMV infections and malignant gliomas have significantly increased. Therefore, we conducted a meta-analysis of observational studies to summarize and pool the available results on the association of HCMV in patients with glioma. Our meta-analysis was based on the PRISMA algorithm, using fixed/random models through STATA IC 13.1 software. Thus, 32 studies were included with a total of 2,190 participants/specimens (glioma, n = 1,871; non-glioma, n = 319). The overall estimate of combined HCMV frequency in patients with glioma was 63% (95% confidence interval [CI]: 56-70). There was an association between HCMV infection and glioma (adjusted OR = 3, 95% CI: 1.7-5.3). The pooled subgroup analysis of viral markers also showed a positive association between the pp65 protein (OR = 3.1, 95% CI: 1.8-5), and gB nucleic acids (OR = 3.1, 95% CI: 1.1-8). For the viral marker IE1-72 protein, the pooled frequency and association results were higher. However, there was no correlation of higher viral association according to the histological subtypes and low/high grade of gliomas. In conclusion, the available evidence suggests an association between HCMV and glioma. Consequently, precautions should be taken, as discussed in this report.

The Epstein-Barr virus latent membrane protein-1 (LMP1) 30-bp deletion and XhoI-polymorphism in nasopharyngeal carcinoma: a meta-analysis of observational studies.

BACKGROUND: Epstein-Barr virus (EBV) is considered to be closely associated with nasopharyngeal carcinoma (NPC), in which EBV-encoded latent membrane protein 1 (LMP1) was found to have an oncogenic role. However, the results published on the LMP1 polymorphism are inconsistent. In the present study, we performed a meta-analysis to determine the frequency of the associations and a more precise association between NPC and EBV LMP1 gene variants (30-bp deletion (del)/XhoI-loss). METHODS: Eligible articles met the inclusion/exclusion criteria and were identified in the following electronic databases: PubMed, ScienceDirect, and SciELO. Consequently, the data of interest were extracted and plotted in a table to calculate the frequency and odds ratio (OR) of the outcomes of interest (30-bp del-LMP1/XhoI-loss) in patients with NPC. Study quality (Newcastle-Ottawa Scale (NOS)), publication bias, and heterogeneity were assessed. RESULTS: Thirty-one observational studies were included with a total of 2,846 individuals (NPC, n = 1,855; control, n = 991). The risk of bias in relation to study quality evaluated by NOS was considered low. The pooled estimate of the frequency of 30-bp del-LMP1 and XhoI-loss in patients with NPC was 77% (95% confidence interval (CI): 72 to 82) and 82% (95% CI: 71 to 92), respectively. There was an association between 30-bp del-LMP1 and NPC susceptibility (OR = 2.86, 95% CI: 1.35 to 6.07, P = 0.00). Similarly, there was an association between XhoI-loss and NPC (OR = 8.5, 95% CI: 1.7 to 41, P = 0.00). However, when we analyze the co-existence of the 30-bp del-LMP1 and XhoI-loss in patients with NPC, there was no association (OR = 1.09, 95% CI: 0.06 to 18.79, P = 0.002). CONCLUSIONS: Our results suggest an association between the 30-bp del-LMP1 and XhoI-loss with NPC susceptibility. However, our data should be interpreted with caution because the sample size was small, and there was heterogeneity between the studies. Thus, future studies are needed with adjusted estimates to simultaneously evaluate multiple factors involved in the development of NPC. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42014013496 .

Safety, immunogenicity and efficacy of a recombinant tetravalent dengue vaccine: a meta-analysis of randomized trials.

The World Health Organization has stipulated a target: reduce the mortality rate caused by dengue disease by 50% until 2020. Most likely, this goal can be achieved by means of a dengue vaccine. Accordingly, the recombinant and tetravalent dengue vaccine (CYD-TDV), developed by the Sanofi Pasteur Group, is in an advanced stage of human testing. Although there are multiple randomized, placebo-controlled trials evaluating the CYD-TDV, individual results may have little power to identify differences between the populations studied. Thus, we conducted a meta-analysis to determine a more precise estimate of the overall parameters of safety, immunogenicity and efficacy of CYD-TDV. A data search was conducted in the PubMed, Medline, Cochrane Central Register of Controlled Trials and SciELO databases with defined selection criteria. We included for meta-analysis seven randomized and placebo-controlled studies that included 6678 patients randomized to receive the CYD-TDV (4586) or placebo (2092). Regarding vaccine safety, it was found that there was no significant difference between treated and placebo groups, as only approximately 5.5% of patients were withdrawn from the study. Regarding immunogenicity, the levels of neutralizing antibodies were measured by weighted mean differences (WMD), which were always higher in the vaccinated group (WMD/DENV1=59.7, 95% confidence interval [CI] 57-61; WMD/DENV2=99, 95% CI 95-102; WMD/DENV3=138, 95% CI 133-142; WMD/DENV4=123, 95% CI 119-126). The clinical efficacy of the vaccine was 59% (95% CI 15-80; RR=0.41, 95% CI 0.2-0.85, I(2)=30.9%). In conclusion, safety and a balanced immune response to the CYD-TDV were found. However, to fully establish the clinical effectiveness and robustness of immunogenicity, it is necessary to perform further studies to assess the long-term effects of the vaccine.

A meta-analysis of the diagnostic accuracy of two commercial NS1 antigen ELISA tests for early dengue virus detection.

BACKGROUND: Dengue virus (DENV) NS1 antigen detection is regarded as an early diagnostic marker. Accordingly, several studies have evaluated the performance of tests that utilize NS1 capture, but the results of individual studies may be limited due to the restricted sample size of the patients recruited. Therefore, our objective was to perform a meta-analysis of the diagnostic accuracy of two commercial NS1 ELISAs (Panbio and Platelia). METHODS AND RESULTS: Studies of interest were found in PubMed, Embase and Google Scholar databases using defined inclusion/exclusion criteria. A total of 30 studies containing 12,105 total enrolled patients were included. The results were as follows: 1) Panbio assays showed low overall performance, sensitivity 66% (95% confidence interval (CI) 61-71), specificity 99% (95% CI 96-100), positive likelihood ratio (LR+) 98 (95% CI 20-464), negative likelihood ratio (LR-) 0.3 (95% CI 0.2-0.4), diagnostic odds ratio (DOR) 289 (95% CI 59-1412); 2) Platelia assays showed high overall performance, sensitivity 74% (95% CI 63-82), specificity 99% (95% CI 97-100), LR+ 175 (95% CI 28-1099), LR- 0.3 (95% CI 0.2-0.4), DOR 663 (95% CI 98-4478). The lowest sensitivity values were for secondary infections (57% [95% CI 47-67] and 66% [95% CI 53-77] for Panbio and Platelia, respectively) and for the detection of DENV4. Regarding clinical manifestations, the sensitivity of Platelia was 69% (95% CI 43-86) and 60% (95% CI 48-70) for fever and dengue hemorrhagic fever, respectively. In addition, the sensitivity of both tests was slightly lower for samples from Southeast Asia and Oceania. CONCLUSION: DENV1 samples gave higher sensitivity results for both tests. We observed that factors negatively influencing the tests, such as the type of infection, geographical origins of samples and viral serotypes, require further investigation to optimize the diagnostic accuracy.

Effectiveness of the ribavirin in treatment of hantavirus infections in the Americas and Eurasia: a meta-analysis.

Hemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS) are transmitted to humans through infection with the old- and new-world hantaviruses, respectively. Together these diseases affect tens of thousands of people every year, and no specific treatment is available. To investigate whether ribavirin treatment for hantaviruses infections decreases disease severity, we conducted a meta-analysis involving human and animal studies. After defining the research protocol and criteria for inclusion/exclusion, we identified seven studies. We found that in groups with HPS who were treated with ribavirin, there was no significant reduction in mortality (RR 0.99, 95 % CI 0.60-1.61, I(2) = 0 %). On the other hand, for animal group with HPS-like disease, there was significant increase in survival (RR 0.05, 95 % CI 0.01-0.34, I(2) = 0 %). For animal group infected with the old-world hantaviruses, treated with ribavirin, there was a statistically significant increase in survival (RR 0.56, 95 % CI 0.42-0.76, I(2) = 64 %). Similarly, for humans with HFRS treated, there was increase in survival (RR 0.28, 95 % CI 0.08-1), although only a study exist. Our meta-analysis provides data that should be interpreted with caution, partly due to the limited number of studies available. Additionally, the results of the application of ribavirin in the population with HPS could not be determined, particularly in patients in the end stage of this disease.