Dados do Trabalho

Título

Rapid epidemic expansion of chikungunya virus-ECSA lineage in Paraguay

Introdução

Chikungunya is a mosquito-borne viral disease caused by the chikungunya virus (CHIKV), a single-stranded positive-sense RNA virus belonging to the Togaviridae family (Schwartz et al., 2010). The virus is transmitted to humans through the bite of infected Aedes mosquitoes. Classically, it is an acute self-limiting illness characterized by fever and severe joint pain, but persistent or relapsing joint pain can occur (Schwartz et al., 2010). Atypical and severe manifestations (including meningoencephalitis) have been reported, and death is usually associated with extremes of age and/or underlying disease. Mother-to-child transmission of CHIKV does occur and neonatal disease can be severe, with neurological, myocardial, or haemorrhagic disease (Schwartz et al., 2010). The first imported case of CHIKV in Paraguay was detected in June 2014, in a patient from the Dominican Republic.

Objetivo (s)

The spread of arboviruses, such as the CHIKV, is a significant public health concern in the Americas, with over 120,000 cases and 51 deaths in 2023, of which 46 occurred in Paraguay. Using a suite of genomics, phylodynamic, and epidemiological techniques, we characterize the ongoing large CHIKV epidemic in Paraguay

Material e Métodos

We partnered with the Pan-American Health Organization (PAHO) to perform on-site genomic surveillance monitoring at the Laboratorio Central de Salud Pública in Asunción, Paraguay. Between March 11 to 17, 2023, generating 179 viral genomes. Genome sequencing was conducted using the Nanopore technology. We then constructed phylogenetic trees to explore the relationship of the sequenced genomes from Paraguay to those of other global isolates of this genotype.

Resultados e Conclusão

The fast and large re-emergence in 2022 coincided with the maximum mean temperatures ever reported. And the most of the generated genomes were from outcomes defined as outpatients (58%), followed by fatal (18%), intensive care unit (17%) and inpatient (7%) infections. Compared with an outpatient outcome, there was a clear association of fatal outcomes with older age-groups. The same comparison with outcomes requiring medical attention (ICU, inpatients) was not statistically significant.
Our findings provide evidence of lineage persistence in the country over a period of 11 months preceding resurgence and present the notable coincidence of resurgence happening alongside the highest mean temperatures ever recorded in Paraguay. The spread of CHIKV is a significant public health concern in the Americas.

Palavras-chave

CHIKV

Agradecimentos

NIH and PAHO/WHO