Evolution of antibodies against SARS-CoV-2 over seven months: Experience of the nationwide seroprevalence ENE-COVID study in Spain.

Background: The main aims of this study were to analyze trends of SARS-CoV-2 anti-nucleocapsid IgG throughout the four rounds of the seroepidemiologic study ENE-COVID, and compare the fourth-round results of two immunoassays detecting anti-nucleocapsid and anti-RBD IgG.

Methods: ENE-COVID was developed in 2020 (two phases). Phase one included three rounds carried out in April 27-May 11, May 18-June 1, and June 8-June 22.

Toscana virus infection in Catalonia (Spain).

Toscana virus (TOSV), an arthropod-borne phlebovirus, is an important agent of acute meningitis and meningoencephalitis in the Mediterranean area. The epidemiology of the infection in humans in Catalonia is at present unknown. In this study, we found a seroprevalence of infection of 6%, and 2 clinical cases were detected by serology and/or PCR.

BK polyomavirus with archetypal and rearranged non-coding control regions is present in cerebrospinal fluids from patients with neurological complications.

BK polyomavirus (BKPyV) has recently been postulated as an emerging opportunistic pathogen of the human central nervous system (CNS), but it is not known whether specific strains are associated with the neurotropic character of BKPyV. The presence of BKPyV large T-antigen DNA was examined in 2406 cerebrospinal fluid (CSF) samples from neurological patients with suspected JC polyomavirus infection. Twenty patients had a large T-antigen DNA-positive specimen.

Lymphocytic choriomeningitis virus-associated meningitis, southern Spain.

Lymphocytic choriomeningitis virus (LCMV) was detected in 2 patients with acute meningitis in southern Spain within a 3-year period. Although the prevalence of LCMV infection was low (2 [1.3%] of 159 meningitis patients), it represents 2.

Development and validation with clinical samples of internally controlled multiplex real-time PCR for diagnosis of BKV and JCV infection in associated pathologies.

This article describes the development and validation with clinical samples of an internally controlled multiplex quantitative real-time PCR (QRT-PCR) for human polyomaviruses BK (BKV) and JC (JCV). Blood and urine samples from renal transplant recipients with suspected nephropathy, and cerebrospinal fluid (CSF) specimens from AIDS, natalizumab-treated and HIV-negative patients with suspected progressive multifocal leukoencephalopathy, previously checked for BKV and JCV by conventional PCR, were tested by QRT-PCR. All samples positive by conventional PCR were confirmed by QRT-PCR.

BK virus-associated infection in cerebrospinal fluid of neurological patients and mutation analysis of the complete VP1 gene in different patient groups.

While BK virus (BKV) is frequently associated with pathological conditions in bone marrow and renal transplant recipients, BKV infection in neurological individuals has been rarely reported. As a result of a BKV, JCV, and SV40 large T antigen-specific multiplex PCR on 2,062 cerebrospinal fluid (CSF) samples from neurological patients suspicious of JCV infection, we identified 20 subjects with at least 1 CSF specimen positive for BKV large T antigen DNA. Because VP1 protein has been suggested to influence the biological/pathological properties of BKV, we tried to sequence the entire VP1 gene in the BKV-positive neurological patients and succeeded in 14 of the 20 neurological patients.

[Biodefense: a new challenge for microbiology and public health].

Bioterrorism and the potential use of biological weapons has become an important concern of governments and responsible authorities. An example of this threat occurred in 2001 in the USA, when letters were sent containing spores of the agent that produces anthrax; this resulted in some deaths, and caused panic and negative effects on the world economy. If this small-scale event was able to cause such a huge impact, the repercussions of a massive attack could be catastrophic.