As part of the “COVID-19 & Our Future World” leadership talk series at Fulbright University Vietnam, Harvard epidemiologist and Public Health professor Yonatan Grad spoke about his recent research in Science on intermittent social distancing and its implications on Vietnam.
This past Wednesday evening, hundreds of people listened intently to an online speech that professor Yonatan Grad gave with Fulbright University Vietnam. Only hours before giving his talk at Fulbright, Professor Grad was on CNN with Anderson Cooper to share his research on COVID-19. So what did he find, and what are the implications for Vietnam and the region?
Professor Grad began the talk by discussing the question on everyone’s mind: when will this pandemic end? He outlined that there are two scenarios for the virus to end – “total extinction” or “herd immunity,” in which enough people are immune to the virus such that it slowly dies out.
Given the widespread nature of Coronavirus already, professor Grad argued that “total extinction” of the virus seems unlikely. So, how could we possibly get to herd immunity? This could come from either a vaccine or it could come from enough people getting infected over time to develop this immunity. As Grad explained, it’s unclear when or if a vaccine will be developed – and how long it would take to spread across the world. So, their research explores what would happen without it.
Photo: Ngoc Thang – TN
Their model finds that one solution may be “intermittent social distancing” or social distancing that follows an off-and-on pattern. Intermittent social distancing occurs when a country locks down to “flatten the curve” of case counts and reduce the load on the health care system. Then as the virus begins to die out, the country re-opens. Once the virus spreads again and begins to reach that critical threshold, the country returns to social distancing. In Grad and his colleagues’ model, this type of intermittent distancing in the U.S. would need to last until 2022 to reach population-wide immunity.
But, what does that mean for a country like Vietnam that has so far successfully contained the virus? In the Q&A, professor Grad addressed this question and noted that even initially successful countries like Vietnam would likely follow a similar path to herd immunity. Grad used the example of Singapore, which just entered a lockdown for the next month after initially holding back a wave of COVID-19 cases. Even though Vietnam has been successful up to now, it does not mean that a single lockdown may be enough.
When Grad was asked about travel restrictions and their possible timeline, he indicated that travel was one of the core questions in the future. The issue is that even as one region may bring the virus under control, other areas may not – causing possible recontamination. Until herd immunity exists in the population, the population remains susceptible to the virus.
Grad’s model did not directly address the economic outcomes of doing intermittent distancing, but this was one area of future research. As Grad discussed, work on intermittent distancing should combine with research on the economic impact. The combination of those two will allow policy-makers to make decisions about what should and shouldn’t re-open.
Similarly, another area of future research Grad identified is understanding what is most effective in helping reducing transmission – and what is less effective. Many countries, like the U.S., have used all available methods to reduce transmission, such as closing schools, public gatherings, in-person work, etc. However, it may be possible to reduce the transmission rate below an R of 1 (after which the virus dies out) with only some, but not all of these measures.
Grad ended his talk by striking a note that countries could and should learn from one another. Just as Fulbright’s community can help learn from the research that Grad’s team is doing in Cambridge, Massachusetts, so can the United States learn from the effective responses thus far from places like Taiwan, Singapore, and Vietnam.
Stephen Turban
*Yonatan Grad’s talk is part of an on-going series by Fulbright University Vietnam entitled “COVID-19 & Our Future World.” To follow future talks, like Fulbright’s Facebook page here.
