Circulation of chikungunya virus East/Central/South African lineage in Rio de Janeiro, Brazil.

The emergence of chikungunya virus (CHIKV) has raised serious concerns due to the virus' rapid dissemination into new geographic areas and the clinical features associated with infection. To better understand CHIKV dynamics in Rio de Janeiro, we generated 11 near-complete genomes by means of real-time portable nanopore sequencing of virus isolates obtained directly from clinical samples. To better understand CHIKV dynamics in Rio de Janeiro, we generated 11 near-complete genomes by means of real-time portable nanopore sequencing of virus isolates obtained directly from clinical samples. Our phylogenetic reconstructions indicated the circulation of the East-Central-South-African (ECSA) lineage in Rio de Janeiro. Time-measured phylogenetic analysis combined with CHIKV notified case numbers revealed the ECSA lineage was introduced in Rio de Janeiro around June 2015 (95% Bayesian credible interval: May to July 2015) indicating the virus was circulating unnoticed for 5 months before the first reports of CHIKV autochthonous transmissions in Rio de Janeiro, in November 2015. These findings reinforce that continued genomic surveillance strategies are needed to assist in the monitoring and understanding of arbovirus epidemics, which might help to attenuate public health impact of infectious diseases.

Immunoglobulin-like Domain of HsFcµR as a Capture Molecule for Detection of Crimean-Congo Hemorrhagic Fever Virus- and Zika Virus-Specific IgM Antibodies.

BACKGROUND: The cellular surface molecule HsTOSO/FAIM3/HsFcµR has been identified as an IgM-specific Fc receptor expressed on lymphocytes. Here, we show that its extracellular immunoglobulin-like domain (HsFcµR-Igl) specifically binds to IgM/antigen immune complexes (ICs) and exploit this property for the development of novel detection systems for IgM antibodies directed against Crimean-Congo hemorrhagic fever virus (CCHFV) and Zika virus (ZIKV). METHODS: His-tagged HsFcµR-Igl was expressed in Escherichia coli and purified by affinity chromatography, oxidative refolding, and size-exclusion chromatography. Specific binding of HsFcµR-Igl to IgM/antigen ICs was confirmed, and 2 prototypic ELISAs for the detection of anti-CCHFV and anti-ZIKV IgM antibodies were developed. Thereby, patient sera and virus-specific recombinant antigens directly labeled with horseradish peroxidase (HRP) were coincubated on HsFcµR-Igl-coated ELISA plates. Bound ICs were quantified by measuring turnover of a chromogenic HRP substrate. RESULTS: Assay validation was performed using paired serum samples from 15 Kosovar patients with a PCR-confirmed CCHFV infection and 28 Brazilian patients with a PCR-confirmed ZIKV infection, along with a panel of a priori CCHFV/ZIKV-IgM-negative serum samples. Both ELISAs were highly reproducible. Sensitivity and specificity were comparable with or even exceeded in-house gold standard testing and commercial kits. Furthermore, latex beads coated with HsFcµR-Igl aggregated upon coincubation with an IgM-positive serum and HRP-labeled antigen but not with either component alone, revealing a potential for use of HsFcµR-Igl as a capture molecule in aggregation-based rapid tests. CONCLUSIONS: Recombinant HsFcµR-Igl is a versatile capture molecule for IgM/antigen ICs of human and animal origin and can be applied for the development of both plate- and bead-based serological tests.

Zika Virus Infection and Differential Diagnosis in a Cohort of HIV-Infected Patients.

BACKGROUND: Zika virus (ZIKV) emergence in South America revealed the lack of knowledge regarding clinical manifestations in HIV-infected individuals. OBJECTIVES: We described the clinical characteristics, laboratory manifestations, differential diagnosis, and outcome of ZIKV infection in a large, single-center cohort of HIV-infected patients. METHODS: HIV-infected patients aged 18 years and older with clinical suspected arboviral disease from an ongoing cohort were followed from February 2015 through December 2015. Acute serum samples were tested for ZIKV, dengue virus (DENV), and chikungunya virus by real-time reverse transcriptase polymerase chain reaction, anti-DENV immunoglobulin (Ig)M/IgG, and syphilis assays; convalescent samples were tested for anti-DENV IgM/IgG; and urine samples were tested for ZIKV by real-time reverse transcriptase polymerase chain reaction. ZIKV disease was defined according to the Pan American Health Organization (PAHO) guidelines. RESULTS: Of 101 patients, ZIKV was confirmed in 43 cases and suspected in 34, and another diagnosis was assumed for 24 patients (dengue, secondary/latent syphilis, respiratory infections, human parvovirus B19, adverse drug reaction, musculoskeletal disorders, and acute gastroenteritis). ZIKV-confirmed and ZIKV-suspected patients reported similar signs and symptoms. Pruritic rash was the most common symptom, followed by myalgia, nonpurulent conjunctivitis, arthralgia, prostration, and headache. In the short-term follow-up [median 67.5 days (interquartile range: 32-104.5)], CD4 cell count (Z = -0.831, P = 0.406) and HIV viral load (Z = -0.447, P = 0.655) did not change significantly after ZIKV infection. There were no hospitalizations, complications, or deaths. CONCLUSIONS: Among HIV-infected patients with suspected arboviral disease, 42.6% were ZIKV-infected. CD4 cell counts and HIV viral load were not different after ZIKV infection. Differential diagnosis with other diseases and adverse drug reaction should be evaluated.

An observational clinical case of Zika virus-associated neurological disease is associated with primary IgG response and enhanced TNF levels.

Descriptive clinical data help to reveal factors that may provoke Zika virus (ZIKV) neuropathology. The case of a 24-year-old female with a ZIKV-associated severe acute neurological disorder was studied. The levels of ZIKV in the cerebrospinal fluid (CSF) were 50 times higher than the levels in other compartments. An acute anti-flavivirus IgG, together with enhanced TNF-alpha levels, may have contributed to ZIKV invasion in the CSF, whereas the unbiased genome sequencing [obtained by next-generation sequencing (NGS)] of the CSF revealed that no virus mutations were associated with the anatomic compartments (CSF, serum, saliva and urine).

Duplex reverse transcription-PCR followed by nested PCR assays for detection and identification of Brazilian alphaviruses and flaviviruses.

A new approach was developed for the rapid detection and identification of Brazilian alphaviruses and flaviviruses. The methodology involves the genus-specific detection of Alphavirus and Flavivirus by a duplex reverse transcription-PCR (D-RT-PCR), followed by multiplex nested PCR (M-N-PCR) or nested PCR (N-PCR) assays for species-specific identification. By this protocol, 25 arboviruses were specifically detected and identified. Detection levels between 10(1.3) and 10(3.5) 50% tissue culture infective doses (TCID(50))/ml of Flavivirus and Alphavirus strains were achieved by D-RT-PCR, and levels of <1 TCID(50)/ml were achieved by M-N-PCR assays. To assess the suitability and clinical application of this methodology, a total of 101 human or animal stored samples were analyzed. Results obtained suggest that this technique could be applied as a rapid diagnostic tool in clinical samples in which arbovirus infection is suspected and differential diagnosis is required, avoiding the need to test specimens by separate PCR methods.