Zika Virus Outbreak in Haiti in 2014: Molecular and Clinical Data

Abstract

BackgroundZika virus (ZIKV), first isolated in Uganda in 1947, is currently spreading rapidly through South America and the Caribbean. In Brazil, infection has been linked with microcephaly and other serious complications, leading to declaration of a public health emergency of international concern; however, there currently are only limited data on the virus (and its possible sources and manifestations) in the Caribbean.MethodsFrom May, 2014-February, 2015, in conjunction with studies of chikungunya (CHIKV) and dengue (DENV) virus infections, blood samples were collected from children in the Gressier/Leogane region of Haiti who presented to a school clinic with undifferentiated febrile illness. Samples were initially screened by RT-PCR for CHIKV and DENV, with samples negative in these assays further screened by viral culture.FindingsOf 177 samples screened, three were positive for ZIKV, confirmed by viral sequencing; DENV-1 was also identified in culture from one of the three positive case patients. Patients were from two different schools and 3 different towns, with all three cases occurring within a single week, consistent with the occurrence of an outbreak in the region. Phylogenetic analysis of known full genome viral sequences demonstrated a close relationship with ZIKV from Brazil; additional analysis of the NS5 gene, for which more sequences are currently available, showed the Haitian strains clustering within a monophyletic clade distinct from Brazilian, Puerto Rican and Guatemalan sequences, with all part of a larger clade including isolates from Easter Island. Phylogeography also clarified that at least three major African sub-lineages exist, and confirmed that the South American epidemic is most likely to have originated from an initial ZIKV introduction from French Polynesia into Easter Island, and then to the remainder of the Americas.ConclusionsZIKV epidemics in South America, as well as in Africa, show complex dissemination patterns. The virus appears to have been circulating in Haiti prior to the first reported cases in Brazil. Factors contributing to transmission and the possible linkage of this early Haitian outbreak with microcephaly remain to be determined.

Mayaro Virus in Child with Acute Febrile Illness, Haiti, 2015

“…Written parental informed consent was obtained from parents or guardians of all study participants. Plasma samples were screened by reverse transcription PCR (RT-PCR) for CHIKV and dengue virus (DENV); samples that were negative for CHIKV were cultured by using cell lines and conditions as previously described ( 7 ). Zika virus and enterovirus D68 have been previously isolated from members of this school cohort ( 7 , 8 ).…”

Spread of Zika virus in the Americas

“…The virus also circulated early on in the Caribbean, with ZIKV samples isolated in Haiti at the end of 2014, and a possible first peak occurred in October 2015 (47). Colombia first isolated ZIKV in October 2015, at which time it spread rapidly from the Caribbean coast to cities infested with A. aegypti (48).…”

A Screen of FDA-Approved Drugs for Inhibitors of Zika Virus Infection

“…ZIKV remained a footnote among neglected tropical diseases due to the mild disease described from a limited number of cases. That changed in 2007 when ZIKV emerged in a series of outbreaks across the Pacific (Duffy et al, 2009; Dupont-Rouzeyrol et al, 2015; Roth et al, 2014; Tognarelli et al, 2016), and changed dramatically in 2014 and 2015 when Zika exploded into the Americas causing a large and expanding pandemic (Fauci and Morens, 2016; Lednicky et al, 2016). One of the first countries to be affected in the Americas was Brazil, where ZIKV has caused an estimated 1.5 million infections (Weaver et al, 2016).…”