EHS-COVID (262) Estimating and mitigating the risk of COVID-19 epidemic rebound associated with reopening of international borders in Vietnam

20 April, 2021

An interesting study on the application of mathematical modelling to assess the risk of a rebound COVID-19 epidemic on opening of international borders in Vietnam.

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Background: Vietnam has emerged as one of the world’s leading success stories in responding to COVID-19. After a prolonged period of little to no transmission, there was an outbreak of unknown source in July, 2020, in the Da Nang region, but the outbreak was quickly suppressed. We aimed to use epidemiological, behavioural, demographic, and policy data from the COVID-19 outbreak in Da Nang to calibrate an agent-based model of COVID-19 transmission for Vietnam, and to estimate the risk of future outbreaks associated with reopening of international borders in the country.

Interpretation: The successful response to COVID-19 in Vietnam could be improved even further with higher levels of symptomatic testing. If the previous approaches are used in response to new COVID-19 outbreaks, epidemic control is possible even in the presence of low levels of imported cases.

Selected extracts from the paper-

If the population of Vietnam remains highly compliant with mask-wearing policies, our projections indicate that the epidemic would remain under control even if a small but steady flow of imported infections escaped quarantine into the community. However, if complacency increases and testing rates are relatively low (10% of symptomatic individuals are tested), the epidemic could rebound again, resulting in an estimated 2100 infections (95% projected interval 1050-3610) in 3 months. These outcomes could be mitigated if the behaviour of the general population responds dynamically to increases in locally acquired cases that exceed specific thresholds, but only if testing of symptomatic individuals is also increased.

Questions for scope of discussion:

1) How can healthcare settings ensure adequate healthcare delivery and provision of essential healthcare services (eg- adequate testing and screening facilities, medications, PPE kits etc.) during the second wave of COVID-19 affecting many countries?

2) How can we help avoid complacency and pandemic fatigue in both vaccinated and unvaccinated individuals?

3) What measures are required to be taken by countries anticipating to reopen their international borders, to avoid a potential resurgence of cases?


Vedant S Jha

HIFA profile: Vedant Shekhar Jha is a Medical Cadet at the Armed Forces Medical College Pune, India. Professional interests: Palliative care, exploring unmet needs of cancer patients, the effective communication of health awareness. He is a HIFA catalyst on the HIFA working group on Maintaining essential health services during COVID-19.

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