Intrathecal synthesis of antibodies to dengue virus occurs in the CNS. It may be used as a marker of myelitis associated with dengue, and it seems to be related to the pathogenesis of spinal cord disease due to direct viral invasion.

No abstract

Zika virus (ZIKV) transmission through non-mosquito-dependent routes has become increasingly important since reports of sexual transmission. Breastfeeding is a potential means of ZIKV transmission, but data on this remain limited. The cases of four mothers with laboratory-proven infections are reported. No disease evolved in three of the breastfed babies despite detectable maternal viremia and viruria, the presence of viral RNA shedding, and the isolation of infective particles in one milk sample. Fever and rash in one infant of a ZIKV-infected mother proved to be related to chikungunya virus infection. The results suggest that the presence of infective particles in breast milk may not be sufficient for the efficient perinatal transmission of ZIKV.

Dengue infection is a mosquito-borne disease caused by a flavivirus, and is recognized in over 100 countries with 2.5 billion people living in areas of risk. Neurological manifestations such as encephalitis, myelitis, Guillain-Barré syndrome, cranial nerve palsies, neuromyelitis optica, and encephalomyelitis have been recognized as clinical consequences of dengue infection. Meningitis is a rare complication. We report the case of a 24-year-old woman who presented with fever, headache, and nuchal rigidity without the typical symptoms of dengue infection. Cerebrospinal fluid analysis showed lymphocytic pleocytosis with a normal glucose value and negative bacterial and fungal cultures. The etiology of meningitis was confirmed by positive dengue PCR in the serum. This case report highlights dengue infection as a potential cause of meningitis in endemic areas. Also, meningitis can be the first manifestation of the infection. Dengue should be investigated even in the absence of a typical picture of the infection.

The dengue virus belongs to the Flaviviridae family. There are four closely related, but antigenically different virus serotypes: DENV1 to DENV4. An infection caused by one of them can cause dengue fever and, rarely, most severe form of the disease. The infection provides life-long protective immunity to the same subtype, but no immunity against the other three serotypes. Moreover, previous infection with a different subtype increases the chances of developing dengue hemorrhagic fever. This is due to a phenomenon called antibody dependent enhancement (ADE). In ADE, the heterotypic non-neutralizing antibodies form complexes with dengue virus, which infect mononuclear phagocytes with enhanced efficiency. Consequently, a higher number of host cells are infected, improving viral replication, worsening the clinical signs. Thus, this may also contribute to the development of neurological and other complications 1 . The neurological manifestations are mainly associated with DENV-2 and DENV-3. These serotypes were found in cases of encephalitis, meningitis and myelitis 2,3 . DENV-4 was also detected in brain cells by immunohistochemistry and in cerebrospinal fluid (CSF) of a patient with encephalitis 4 . The present article highlights some important points that should be addressed when evaluating a possible case of neurological complication of dengue virus infection. Conflict of interest:There is no conflict of interest. ABStrACtDengue is an important global public health problem. The World Health Organization estimates that 2/5 of entire world population are in risk of dengue infection. Almost 50 millions cases occur annually, with at least 20 thousand deaths. The etiological agent of this acute febrile disease is a single-strand positive-sense RNA virus of Flavivirus genus. It is an arboviral disease transmitted by Aedes sp. mosquitoes (Aedes aegypti and A. albopictus). Most infected individuals present asymptomatic infection, but some may develop clinical signs. Therefore, a wide spectrum of illness can be observed, ranging from unapparent, mild disease, called dengue fever, to a severe and occasionally fatal dengue hemorrhagic fever/dengue shock syndrome. Currently, neurological manifestations related to dengue infections are increasingly been observed and appears as a challenge for medical practice. In this study the neurological complications of dengue infection will be reviewed, focusing a better understanding of the disease for the clinical practice.Keywords: dengue, nervous system, diagnosis. rESUMO A dengue é um importante problema de saúde pública. A Organização Mundial de Saúde estima que 2/5 da população mundial encontra-se em risco de desenvolver a infecção. Cerca de 50 milhões de casos ocorrem anualmente, com ao menos 20 mil mortes. O agente etiológico desta doença febril aguda é um vírus RNA, do gênero Flavivirus. Este arbovírus é transmitido pelo mosquito Aedes sp. A maioria dos indivíduos infectados apresenta infecção assintomática, porém alguns desenvolvem sintomas clínicos. Estes manifestações podem...

No abstract

No abstract

-Background: Dengue infection may cause neurological manifestations such as encephalitis, myelitis, mononeuropathies, acute disseminated encephalomyelitis, and Guillain Barré syndrome (GBS). In endemic regions, the infection course can be oligosymptomatic making difficult the diagnosis of the neurological picture associated with dengue infection. Objective: To report dengue infection and GBS association, even in oligosymptomatic cases of this infection. Method: During the dengue epidemic in Rio de Janeiro city we looked for GBS cases, testing IgM antibodies for dengue and dengue polymerase chain reaction (PCR) in the cerebrospinal fluid (CSF) and serum. Results: We report seven cases (46.6%), presenting dengue positive IgM in serum but with poor or without clinical symptoms of the previous infection. Two of them had also positive IgM antibodies in CSF. Conclusion: These data show that search for dengue infection should be a routine in GBS cases living in endemic areas.Key WoRDS: dengue, polyradiculoneuritis, radiculoneuropathy, CSF, Guillain Barré syndrome. Dengue oligossintomática: causa potencial de síndrome de Guillain BarréResumo -Introdução: o vírus da dengue pode determinar várias manifestações neurológicas como: encefalite, mielite, mononeuropatias, encefalomielite disseminada aguda e a síndrome de Guillain Barré (SGB). em regiões endêmicas a infecção pode ser oligosintomática dificultando o diagnóstico neurológico associado a infecção por dengue. Objetivo: Relatar a associação entre SGB e o vírus da dengue, principalmente em formas oligosintomáticas da infecção. Método: Durante epidemia pelo vírus da dengue na cidade do Rio de Janeiro, casos de SGB foram selecionados e tiveram suas amostras de soro e líquido cefalorraqueano (LCR) testadas para anticorpos dengue IgM e PCR para dengue. Resultados: Descrevemos sete casos (46,6%) com diagnóstico de SGB, apresentando IgM positiva para dengue no soro, porém com poucos ou nenhum sintoma infeccioso prévio. Dois pacientes também apresentavam IgM positiva no LCR. Conclusão: estes dados sugerem que a pesquisa para o vírus da dengue deve ser realizada em todos os casos de SGB em áreas endêmicas.PALAvRAS-ChAve: dengue, polirradiculoneurite, radiculoneuropatia, líquido cefalorraqueano e síndrome de