Estimating the cost of illness of acute Japanese encephalitis and sequelae care in Vietnam and Laos: A cross-sectional study.

BACKGROUND: Japanese encephalitis (JE) is a leading cause of acute encephalitis syndrome and resulting neurological disability in Asia and the Western Pacific. This study aims to estimate the cost of acute care, initial rehabilitation and sequelae care, in Vietnam and Laos. METHODOLOGY: We conducted a cross-sectional retrospective study using a micro-costing approach from the health system and household perspectives. Out-of-pocket direct medical and non-medical costs, indirect costs, and family impact were reported by patients and/or caregivers. Hospitalization costs were extracted from hospital charts. Acute costs covered expenditures from pre-hospital to follow-up visits while sequelae care costs were estimated from expenditures in the last 90 days. All costs are in 2021 US dollars. PRINCIPAL FINDINGS: 242 patients in two major sentinel sites in the North and South of Vietnam and 65 patients in a central hospital in Vientiane, Laos, with laboratory-confirmed JE were recruited regardless of age, sex, and ethnicity. In Vietnam, the mean total cost was $3,371 per acute JE episode (median $2,071, standard error [SE] $464) while annual costs were $404 for initial sequelae care (median $0, SE $220) and $320 for long-term sequelae care (median $0, SE $108). In Laos, the mean hospitalization costs in acute stage were $2,005 (median $1,698, SE $279) and the mean annual costs were $2,317 (median $0, SE $2,233) for initial sequelae care and $89 (median $0, SE $57) for long-term sequelae care. In both countries, most patients did not seek care for their sequelae. Families perceived extreme impact from JE and 20% to 30% of households still had sustained debts years after acute JE. CONCLUSIONS: JE patients and families in Vietnam and Laos suffer extreme medical, economic, and social hardship. This has policy implications for improving JE prevention in these two JE-endemic countries.

Low seroprotection against diphtheria and tetanus in Lao adolescents.

OBJECTIVES: There is currently no booster diphtheria or tetanus vaccine for Lao children before adolescence, despite international recommendations. We investigated seroprotection against diphtheria and tetanus among Lao adolescents. METHODS: Seven hundred seventy-nine serum samples were tested for anti-diphtheria and anti-tetanus antibodies. RESULTS: Overall, 25.8% of the adolescents had antibody titers corresponding to protection against diphtheria and 30.9% to sufficient immunity against tetanus. Female participants >16 years were more likely to be protected against diphtheria (p < 0.001) and tetanus (p < 0.029). CONCLUSION: Low protection against diphtheria and tetanus, possibly due to low vaccination coverage or antibody waning, suggests booster doses are warranted before adolescence.

Lasting benefit of infant hepatitis B vaccination in adolescents in the Lao People's Democratic Republic.

OBJECTIVES: Hepatitis B is endemic in Lao PDR with 8-10% of the adult population being chronically infected. We investigated the impact of hepatitis B vaccination on infection in adolescents born shortly before and after the introduction of the vaccine in 2001. METHODS: 779 students from Vientiane Capital and Bolikhamxay province were tested for HBV markers by ELISA. Socio-demographic information was collected with a standardized questionnaire. Predictors/risk factors for seroprotection or exposure to hepatitis B infection were assessed by bivariate and multivariable analyses. RESULTS: The prevalence of a serological vaccination profile increased significantly after the introduction of the vaccine (13.2%-21.9%, p < 0.05, in Vientiane; 3.0%-19.7%, p < 0.001, in Bolikhamxay), which translated into at least a 2-times lower prevalence of past infection. In logistic regression, older students in Bolikhamxay were less likely to be vaccinated and more likely to have been infected by HBV in the past. CONCLUSION: Even though this study documented a sizable and lasting reduction in past hepatitis B infections in adolescents born after the introduction of infant hepatitis B vaccination, the overall levels of protective anti-HBs were low and warrant at least the introduction of a booster for adolescents. Furthermore, we suggest improving the coverage of the hepatitis B birth dose.