ABSTRACT
ABSTRACT Hand-foot-and-mouth disease (HFMD) is a highly contagious viral disease commonly associated to Enteroviruses (EV). During 2018, Brazil faced massive HFMD outbreaks spread across the country. This study aimed to characterize the EV responsible for the HFMD outbreak that occurred in Paraiba State, Brazilian Northeastern region, in 2018, followed by a phylogenetic analysis to detail information on its genetic diversity. A total of 49 serum samples (one from each patient) collected from children ≤ 15 years old, clinically diagnosed with HFMD were tested for EV using conventional RT-PCR and RT-qPCR. EV infection was confirmed in 71.4% (35/49) of samples. The mean and median ages were 1.83 years and one year old, respectively. Twenty-two EV-positive samples were successfully sequenced and classified as EV-A species; 13 samples were also identified with the CV-A6 genotype. The phylogenetic analysis (VP1 region) of three samples revealed that the detected CV-A6 strains belonged to sub-lineage D3. The CV-A6 strains detected here clustered with strains from South America, Europe and West Asia strains that were also involved in HFMD cases during the 2017-2018 seasons, in addition to the previously detected Brazilian CV-A6 strains from 2012 to 2017, suggesting a global co-circulation of a set of different CV-A6 strains introduced in the country at different times. The growing circulation of the emerging CV-A6 associated with HFMD, together with the detection of more severe cases worldwide, suggests the need for a more intense surveillance system of HFMD in Brazil. In addition, this investigation was performed exclusively on serum samples, and the analysis of whole blood samples should be considered and could have shown advantages when employed in the diagnosis of enteroviral HFMD outbreaks.
ABSTRACT
OBJETIVO: Confirmar a circulação do vírus Zika e descartar outros agentes etiológicos em surto ocorrido no Rio Grande do Norte (RN), Maranhão (MA) e Paraíba (PB), em maio/2015. MÉTODOS: estudo descritivo de série de casos com residentes em Natal-RN, Barra do Corda-MA, São Luís-MA e João Pessoa-PB, 20 em cada estado, com exantema e ausência de febre ou febre baixa e um dos seguintes sinais/sintomas, hiperemia conjuntival, artralgia ou edema de membros; realizou-se RT-PCR/isolamento para Zika, enterovírus e vírus respiratórios, e sorologias (dengue, rubéola e parvovírus B19). RESULTADOS: os principais sintomas foram exantema (n=60), prurido (n=54) e artralgia (n=47); 51 indivíduos não apresentaram febre; identificou-se vírus Zika em 18 casos (12 na PB, quatro no MA e dois no RN) e anticorpos para dengue em 14. CONCLUSÃO: os sintomas foram compatíveis com febre pelo vírus Zika; houve confirmação laboratorial de Zika e dengue.
OBJETIVOS: confirmar la circulación del virus Zika y descartar otros agentes etiológicos en el brote ocurrido en Rio Grande do Norte (RN), Maranhão (MA) y Paraíba (PB), en mayo/2015. MÉTODOS: estudio descriptivo de serie de casos con residentes de Natal-RN, Barra do Corda-MA, São Luís-MA y João Pessoa-PB, 20 en cada estado, con exantema y ausencia de fiebre o fiebre baja y uno de los siguientes signos/síntomas, hiperemia conjuntival, artralgia o edema de miembros; se realizaron RT-PCR/aislamiento para Zika, enterovirus y virus respiratorios y serologías (dengue, rubéola y parvovirus B19). RESULTADOS: los principales síntomas fueron exantema (n=60), prurito (n=54) y artralgia (n=47); 51 individuos no presentaron fiebre, se identificó virus Zika en 18 casos (12 en PB, cuatro en MA y dos en RN) y anticuerpos para dengue en 14. CONCLUSIÓN: Los síntomas fueron compatibles con fiebre por el virus Zika; hubo confirmación por laboratorio de Zika y dengue.
OBJECTIVE: to confirm Zika virus circulation and discard other etiological agents in an outbreak occurred in the states of Rio Grande do Norte, Maranhão and Paraíba, in May, 2015. METHODS: this is a case series descriptive study with residents in Natal-RN, Barra do Corda-MA, São Luis-MA and João Pessoa-PB, with 20 cases in each state, presenting rash, absent or mild fever and one of the following signs/symptoms: conjunctival hyperemia, arthralgia or limb edema; RT-PCR/isolation tests for Zika, enterovirus and respiratory viruses, and serology tests (dengue, rubella and parvovirus B19) were performed. RESULTS: the main symptoms were rash (n=60), pruritus (n=54), and arthralgia (n=47); 51 individuals did not present fever; Zika virus was identified in 18 cases (12 in Paraíba, four in Maranhão and two in Rio Grande do Norte), and antibodies to dengue, in 14 cases. CONCLUSION: the symptoms were consistent with Zika virus fever; there was laboratory confirmation for Zika and dengue.