Infeção pelo Vírus Zika

Classificação

Características Gerais e Epidemiologia

Características Gerais

• Género: Flavivirus Flavivirus A genus of flaviviridae containing several subgroups and many species. Most are arboviruses transmitted by mosquitoes or ticks. The type species is yellow fever virus. Tick-borne Encephalitis Virus
• Também classificado como um arbovírus porque é transmitido por um artrópode.
• Estrutura:
  • Sentido positivo
  • RNA RNA A polynucleotide consisting essentially of chains with a repeating backbone of phosphate and ribose units to which nitrogenous bases are attached. RNA is unique among biological macromolecules in that it can encode genetic information, serve as an abundant structural component of cells, and also possesses catalytic activity. RNA Types and Structure de cadeia simples linear
  • Com invólucro
  • Cápside icosaédrica

Epidemiologia

• Identificado pela primeira vez no Uganda em 1947
• Agora encontra-se amplamente distribuído nas regiões tropicais e subtropicais da:
  • Ásia
  • África
  • Micronésia
  • América Central e do Sul
• Foram recentemente reportados surtos locais nos Estados Unidos.
• Os casos de zika Zika Zika virus belongs to the genus Flavivirus and is primarily transmitted by Aedes aegypti mosquitoes, but can also be transmitted sexually and transplacentally. Although most infected patients are asymptomatic, some may present with low-grade fever, pruritic rash, and conjunctivitis. Zika Virus Infection nas Américas diminuíram de 40.000 em 2022 para 8.750 em meados de 2023, uma redução de 59%.

Patogénese

Reservatórios

• Humanos
• Primatas não humanos

Transmissão

• Transmitido habitualmente pelos mosquitos Aedes aegypti
• Pode ocorrer transmissão transplacentária se as grávidas forem infetadas.
• A transmissão sexual é possível

Fatores de risco do hospedeiro

• Viagem recente para áreas endémicas (áreas tropicais e subtropicais)
• Relação sexual com um indivíduo atualmente ou recentemente infetado

Fisiopatologia

• O mosquito A. aegypti funciona como vetor:
  • O vírus Zika Zika Zika virus belongs to the genus Flavivirus and is primarily transmitted by Aedes aegypti mosquitoes, but can also be transmitted sexually and transplacentally. Although most infected patients are asymptomatic, some may present with low-grade fever, pruritic rash, and conjunctivitis. Zika Virus Infection replica-se no intestino médio do mosquito.
  • Após a replicação, o vírus aloja-se nas glândulas salivares do mosquito.
• O mosquito pica Pica Pica is an eating disorder characterized by a desire or recurrent compulsion to eat substances that are nonnutritive and not food. These compulsions and ingested substances are inappropriate for age or culture. Pica um hospedeiro humano, inoculando o vírus nos queratinócitos.
• O vírus desloca-se para os gânglios linfáticos antes de ocorrer disseminação sistémica.
• Na síndrome congénita do vírus Zika Zika Zika virus belongs to the genus Flavivirus and is primarily transmitted by Aedes aegypti mosquitoes, but can also be transmitted sexually and transplacentally. Although most infected patients are asymptomatic, some may present with low-grade fever, pruritic rash, and conjunctivitis. Zika Virus Infection, este infeta as células progenitoras neurais do feto.

Apresentação Clínica

Infeção pelo vírus Zika Zika Zika virus belongs to the genus Flavivirus and is primarily transmitted by Aedes aegypti mosquitoes, but can also be transmitted sexually and transplacentally. Although most infected patients are asymptomatic, some may present with low-grade fever, pruritic rash, and conjunctivitis. Zika Virus Infection em adultos

• Período de incubação: 3-14 dias
• A maioria dos doentes permanece assintomático após o período de incubação.
• Se sintomáticos, os achados são inespecíficos:
  • Cefaleias
  • Artralgias
  • Mialgias
  • Febre
  • Exantema pruriginoso
  • Conjuntivite não exsudativa
• Potenciais complicações:
  • Síndrome de Guillain-Barré
  • Meningoencefalite
  • Mielite transversa

Síndrome congénita do vírus Zika Zika Zika virus belongs to the genus Flavivirus and is primarily transmitted by Aedes aegypti mosquitoes, but can also be transmitted sexually and transplacentally. Although most infected patients are asymptomatic, some may present with low-grade fever, pruritic rash, and conjunctivitis. Zika Virus Infection

• É a complicação mais MAIS Androgen Insensitivity Syndrome preocupante da infeção pelo vírus Zika Zika Zika virus belongs to the genus Flavivirus and is primarily transmitted by Aedes aegypti mosquitoes, but can also be transmitted sexually and transplacentally. Although most infected patients are asymptomatic, some may present with low-grade fever, pruritic rash, and conjunctivitis. Zika Virus Infection
• O vírus Zika Zika Zika virus belongs to the genus Flavivirus and is primarily transmitted by Aedes aegypti mosquitoes, but can also be transmitted sexually and transplacentally. Although most infected patients are asymptomatic, some may present with low-grade fever, pruritic rash, and conjunctivitis. Zika Virus Infection infeta as células neuroprogenitoras do SNC.
• Os achados incluem:
  • Calcificações subcorticais
  • Microcefalia
  • Ventriculomegalia
  • Defeitos oculares
  • Espasticidade
  • Convulsões

Diagnóstico e Tratamento

Diagnóstico

• Estudos diagnósticos específicos consoante o tempo desde a infeção:
  • 0 a 14 dias após a infeção: RT-PCR RT-PCR A variation of the pcr technique in which cDNA is made from RNA via reverse transcription. The resultant cDNA is then amplified using standard pcr protocols. Polymerase Chain Reaction (PCR) de amostras de sangue ou de urina para detetar o RNA RNA A polynucleotide consisting essentially of chains with a repeating backbone of phosphate and ribose units to which nitrogenous bases are attached. RNA is unique among biological macromolecules in that it can encode genetic information, serve as an abundant structural component of cells, and also possesses catalytic activity. RNA Types and Structure do vírus Zika Zika Zika virus belongs to the genus Flavivirus and is primarily transmitted by Aedes aegypti mosquitoes, but can also be transmitted sexually and transplacentally. Although most infected patients are asymptomatic, some may present with low-grade fever, pruritic rash, and conjunctivitis. Zika Virus Infection
  • > 14 dias após a infeção: serologia (para anticorpos contra Zika Zika Zika virus belongs to the genus Flavivirus and is primarily transmitted by Aedes aegypti mosquitoes, but can also be transmitted sexually and transplacentally. Although most infected patients are asymptomatic, some may present with low-grade fever, pruritic rash, and conjunctivitis. Zika Virus Infection)
• Alterações laboratoriais inespecíficas:
  • Leucopenia
  • Trombocitopenia
  • PCR PCR Polymerase chain reaction (PCR) is a technique that amplifies DNA fragments exponentially for analysis. The process is highly specific, allowing for the targeting of specific genomic sequences, even with minuscule sample amounts. The PCR cycles multiple times through 3 phases: denaturation of the template DNA, annealing of a specific primer to the individual DNA strands, and synthesis/elongation of new DNA molecules. Polymerase Chain Reaction (PCR) e velocidade de sedimentação (VS) elevadas
• Realizar PCR PCR Polymerase chain reaction (PCR) is a technique that amplifies DNA fragments exponentially for analysis. The process is highly specific, allowing for the targeting of specific genomic sequences, even with minuscule sample amounts. The PCR cycles multiple times through 3 phases: denaturation of the template DNA, annealing of a specific primer to the individual DNA strands, and synthesis/elongation of new DNA molecules. Polymerase Chain Reaction (PCR) ou serologias para descartar coinfeção pelo vírus da dengue Dengue An acute febrile disease transmitted by the bite of aedes mosquitoes infected with dengue virus. It is self-limiting and characterized by fever, myalgia, headache, and rash. Severe dengue is a more virulent form of dengue. Dengue Virus ou da febre amarela.

Tratamento

• Não há tratamentos curativos disponíveis.
• Tratamento sintomático:
  • Fluidoterapia oral ou IV para manter uma hidratação adequada
  • Paracetamol paracetamol Acetaminophen is an over-the-counter nonopioid analgesic and antipyretic medication and the most commonly used analgesic worldwide. Despite the widespread use of acetaminophen, its mechanism of action is not entirely understood. Acetaminophen para diminuir a febre e as artralgias
• Notificação obrigatória.

Comparação entre Espécies

Diagnóstico Diferencial

As seguintes doenças constituem diagnósticos diferenciais da síndrome congénita do vírus Zika Zika Zika virus belongs to the genus Flavivirus and is primarily transmitted by Aedes aegypti mosquitoes, but can also be transmitted sexually and transplacentally. Although most infected patients are asymptomatic, some may present with low-grade fever, pruritic rash, and conjunctivitis. Zika Virus Infection:

• Toxoplasmose congénita: infeção congénita do grupo TORCHES causada pelo protozoário Toxoplasma Toxoplasma Toxoplasmosis is an infectious disease caused by Toxoplasma gondii, an obligate intracellular protozoan parasite. Felines are the definitive host, but transmission to humans can occur through contact with cat feces or the consumption of contaminated foods. The clinical presentation and complications depend on the host’s immune status. Toxoplasma/Toxoplasmosis gondii. A toxoplasmose é habitualmente transmitida pela ingestão de carne de porco mal cozinhada, mas também pode ser transmitida pelo contato com fezes de gato. A toxoplasmose congénita apresenta-se com a tríade de coriorretinite, hidrocefalia e calcificações intracranianas difusas (em vez de subcorticais). O diagnóstico é feito através da serologia. O tratamento faz-se com pirimetamina-sulfadiazina.
• Infeção congénita por citomegalovírus: infecção congénita do grupo TORCHES causada pelo citomegalovírus, também conhecido como herpesvírus humano 5 (HHV-5). O citomegalovírus pode ser transmitido pela urina, sangue, saliva, relação sexual e transplante de órgãos. O citomegalovírus congénito manifesta-se por hipoacúsia, convulsões, exantema cutâneo em “muffin de mirtilo” e calcificações periventriculares (em vez de subcorticais). O diagnóstico é feito por serologia ou PCR PCR Polymerase chain reaction (PCR) is a technique that amplifies DNA fragments exponentially for analysis. The process is highly specific, allowing for the targeting of specific genomic sequences, even with minuscule sample amounts. The PCR cycles multiple times through 3 phases: denaturation of the template DNA, annealing of a specific primer to the individual DNA strands, and synthesis/elongation of new DNA molecules. Polymerase Chain Reaction (PCR). Para o tratamento utiliza-se ganciclovir Ganciclovir An acyclovir analog that is a potent inhibitor of the herpesvirus family including cytomegalovirus. Ganciclovir is used to treat complications from aids-associated cytomegalovirus infections. Antivirals for Herpes Virus ou valganciclovir.
• Infeção congénita por herpes: infeção congénita do grupo TORCHES causada pelo vírus herpes simplex Herpes Simplex A group of acute infections caused by herpes simplex virus type 1 or type 2 that is characterized by the development of one or more small fluid-filled vesicles with a raised erythematous base on the skin or mucous membrane. It occurs as a primary infection or recurs due to a reactivation of a latent infection. Congenital TORCH Infections ( HSV HSV Herpes simplex virus (HSV) is a double-stranded DNA virus belonging to the family Herpesviridae. Herpes simplex virus commonly causes recurrent infections involving the skin and mucosal surfaces, including the mouth, lips, eyes, and genitals. Herpes Simplex Virus 1 and 2) 2. O vírus do herpes simples é transmitido por via transvaginal da mãe infetada para o feto quando este contacta com lesões no canal do parto. A infeção congénita por herpes manifesta-se por vesículas na pele e mucosas semelhantes às observadas nos adultos. Porém, também pode ser disseminada e envolver múltiplos órgãos. O diagnóstico é confirmado por PCR PCR Polymerase chain reaction (PCR) is a technique that amplifies DNA fragments exponentially for analysis. The process is highly specific, allowing for the targeting of specific genomic sequences, even with minuscule sample amounts. The PCR cycles multiple times through 3 phases: denaturation of the template DNA, annealing of a specific primer to the individual DNA strands, and synthesis/elongation of new DNA molecules. Polymerase Chain Reaction (PCR) e o tratamento faz-se com aciclovir.