Mother-to-child Chikungunya Virus Transmission in Mae Sot District, Tak Province, Thailand 2019

Abstract

Background : Based on the epidemiological data of the Department of Disease Control (DDC), Ministry of Public Health (MOPH), outbreaks of chikungunya fever were reported in Thailand in 2019. Tak Province was one of the four affected provinces. Morbidity rate in the province was 138.39 per 100,000 populations. Mae Sot District, Tak Province, was one of the districts where there were suspected cases of chikungunya virus infection, whose signs and symptoms typically included fever, joint pain, and rash. This patient population also included pregnant women who had signs of chikungunya fever around the time of birth. Chikungunya virus could have been transmitted from mothers to their children as it was found that some newborns had shown similar signs (fever, rash, swelling) to those of their mothers within the first week of life.Objective : To study clinical signs and symptoms of chikungunya fever in neonates, clinical complications, and laboratory findings.Method : A descriptive study was conducted to monitor and observe signs, symptoms and laboratory findings of newborns who contracted chikungunya virus from their mothers, who had clinical signs within one week before delivery. Data were collected from June to October 2019, at Mae Sot General Hospital, Mae Sot District, Tak Province. Both newborns and mothers had blood samples collected and confirmatory laboratory testing was performed using chikungunya IgM antibody assay and/or chikungunya polymerase chain reaction (PCR) technique.Result : Six pregnant women developed fever, joint pain, and rash prior to delivery, 83% had positive IgM. All neonates born from six mothers developed fever and maculopapular rash. Signs and symptoms observed in up to 5 newborns (83.3%) included diffuse, limbs edema, irritability, respiratory distress and hyperpigmentation. Other signs and symptoms included poor feeding (50%), seizure and clinical encephalitis (33.3%) and hemodynamic instability (16.7%). Abnormal laboratory findings were observed. Six newborns had positive IgM and three had positive PCR. Two newborns developed encephalitis. No fatal outcomes.Conclusion : Chikungunya virus can be vertically transmitted from the mother to her child during pregnancy. Affected newborns may develop sepsis-like illness. Vertical transmission of chikungunya can lead to severe complications, particularly neurological involvement. It is important to consider chikungunya as differential diagnosis in newborns with sepsis and, or encephalitis in the outbreaks areas.