ABSTRACT
Acute haemorrhagic conjunctivitis outbreaks are often attributed to viral infection. In 2014, an unprecedented nationwide outbreak of infectious conjunctivitis occurred in Thailand, which affected >300 000 individuals over 3 months. To identify and characterize the virus responsible for the epidemic, eye swab specimens from 119 patients were randomly collected from five different provinces. Conserved regions in the enteroviral 5'-UTR and adenovirus hexon gene were analysed. Enterovirus was identified in 71·43% (85/119) of the samples, while no adenovirus was detected. From enterovirus-positive samples, the coxsackievirus A24 variant (70·59%, 84/119) and echovirus (0·84%, 1/119) were identified. Additional sequencing of full-length VP1 and 3C genes and subsequent phylogenetic analysis revealed that these clinical isolates form a new lineage cluster related to genotype IV-C5. In summary, the coxsackievirus A24 variant was identified as an aetiological agent for the recent acute haemorrhagic conjunctivitis outbreak in Thailand.
Subject(s)
Conjunctivitis, Acute Hemorrhagic/epidemiology , Conjunctivitis, Acute Hemorrhagic/virology , Coxsackievirus Infections/epidemiology , Coxsackievirus Infections/virology , Disease Outbreaks , Enterovirus C, Human/isolation & purification , 5' Untranslated Regions , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Cluster Analysis , Enterovirus B, Human/classification , Enterovirus B, Human/genetics , Enterovirus B, Human/isolation & purification , Enterovirus C, Human/classification , Enterovirus C, Human/genetics , Female , Humans , Infant , Male , Middle Aged , Molecular Sequence Data , Phylogeny , Sequence Analysis, DNA , Sequence Homology , Thailand/epidemiology , Viral Proteins/genetics , Young AdultABSTRACT
Visceral leishmaniasis (VL) is a rare disease in Thailand. Only one previous case has been reported in which transmission was likely autochthonous. We conducted an investigation of a case of VL, which included serological and symptom surveys of people who lived near the case in Nan Province and Bangkok, serological surveys of domestic animals in his home village and sand fly surveys in his home village and in Bangkok. No humans interviewed met our case definition for possible VL. One hundred thirty-one villagers were seronegative for Leishmania antibodies. We found three cows and one cat that had positive direct agglutination tests for Leishmania spp, but we were unable to confirm current infection by PCR. Sand fly surveys showed that most of the flies were of the Sergentomyia genus, which has not previously been reported as a competent vector in Thailand. Nonetheless, we conclude, based on the patient's lack of travel outside Thailand and the presence of seropositive domestic animals in his home village, that he was most likely infected by the bite of a sand fly in Thailand. We believe this is the second case of autochthonously transmitted VL in Thailand.