COVID-19 among High-risk Working Populations in Vietnam

Abstract

With nearly eight hundred million cases and seven million lives lost globally, COVID-19 is the deadliest pandemic in history, imposing significantly physical and mental health burdens. Among populations, migrants and healthcare workers face the highest infection risk and suffer heavy impacts. In Vietnam there has been a scarcity of studies on infection, reinfection, risk factors, and the consequences of COVID-19 among such high-risk working populations. This dissertation, comprising three chapters, aims to address this gap in literature. Chapter 1, “Effect of Migration Status on Severity and Hospital Stay Length of COVID-19 Patients in Vietnam: A Health Surveillance Study during the Fourth Wave”, used hospital-based COVID-19 surveillance data at a district health center in Bac Ninh province. This study found that migration status was associated with severity levels among patients with non-migrants experiencing a higher proportion of moderate and severe symptoms, longer hospital stay compared to migrants. Age, gender, total vaccine doses received, and the interval between the last dose and hospital admission were associated with extended hospitalizations in both groups. Chapter 2, “COVID-19 Reinfection and Work Environment Factors Among Healthcare Workers in Vietnam'' utilized data from a prospective cohort study, following 875 healthcare workers in Bac Ninh and Nghe An provinces. A reinfection rate of 1.11 cases per 1000 person-days was observed. We found healthcare workers who used all preventive measures in medical settings had an increased risk of reinfection, which may reflect more exposure to infected patients. Using all prevention measures in the community and having recommended prevention resources available in hospitals reduced the risk. The risk was lower among females, older individuals, and nurses, but higher among unvaccinated or partially vaccinated individuals. Finally, Chapter 3 “Facing the Frontlines: COVID-19 Risk Perception and Mental Health of Vietnamese Medical Students” analyzed data from the survey with 304 Hanoi Medical University students who were mobilized to assist frontline public health responses. Results showed 16.1% of students having depression, 23% having anxiety and 16.1% having stress symptoms. Nearly half of students had high scores for the risk perception of COVID-19. The study identified a positive association between the risk perception score and depression, anxiety, and stress score. These findings highlight the need for prevention strategies such as tailored vaccination campaigns considering migration status, health promotion activities to encourage consistent use of prevention measures in community. Furthermore, providing counselling services for healthcare workers with mental health symptoms is crucial for an effective public health response.