AP Photograph/John Minchillo
The coronavirus was nonetheless a far-away downside in Wuhan when U.S. President Donald Trump introduced a ban on journey from China in late January 2020. Six weeks later, because the coronavirus ravaged Italy, Trump closed journey from Europe.
These journey bans have been extremely controversial. Some folks argued that they have been pointless restrictions on journey. Others mentioned they got here too late. As New York’s COVID-19 case numbers shot upward, Gov. Andrew Cuomo mentioned the U.S. had “closed the entrance door with the China ban … however we left the again door large open,” as a result of the virus had already unfold to different international locations.
One large query stays: As soon as the virus was within the U.S., how a lot affect did worldwide journey even have on COVID-19 instances and deaths?
As researchers with expertise finding out airways, we pulled collectively information to begin answering that query. We in contrast COVID-19 instances and deaths in almost 1,000 U.S. counties in opposition to the numbers of passengers arriving in every from two international locations focused by the bans – China and Italy.
Our outcomes, launched as a preprint research, counsel that vacationers coming from Italy drove the primary wave within the U.S. greater than these from China. In addition they level to 2 conclusions about journey bans:
First, if a authorities goes to impose a journey ban, it ought to act rapidly. The virus spreads quick.
Second, don’t impose slim journey bans that simply goal particular person international locations. As a result of the virus spreads so rapidly, it’s important to assume the virus has already unfold to different international locations.
We’re discussing our findings earlier than the paper has undergone peer overview as a result of the outcomes are vital for choices being made now. On Jan. 25, 2021, nearly a 12 months after Trump’s ban on journey from China, the Biden administration issued new journey bans on international locations which have rising numbers of latest fast-spreading variants of SARS-CoV-2.
Italy versus China
In our research, we used information on worldwide airline journey and U.S. county-level statistics on COVID-19 instances and deaths. We wished to seek out out: Did U.S. counties with extra arrivals from two preliminary COVID-19 sizzling spots – Italy and China – expertise extra COVID-19 instances or deaths in the course of the first U.S. wave of the pandemic?
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There are a number of challenges in making an attempt to evaluate the connection between worldwide journey and COVID-19 outbreaks. Fewer folks may journey to cities which are within the midst of a pandemic outbreak. The areas that appeal to many overseas vacationers may additionally have extra extreme COVID-19 outbreaks for different causes. For instance, locations attracting numerous overseas vacationers could have extra giant occasions similar to conferences and sporting occasions.
We used information on passengers arriving from non-COVID-19 sizzling spots to assist management for these elements. We additionally took into consideration different elements that may have an effect on the virus’s unfold and affect, similar to inhabitants measurement and density, use of public transportation, demographics, insurance policies and financial exercise.
We got here away with two key outcomes:
U.S. counties that acquired extra passengers from China firstly of the pandemic didn’t expertise greater COVID-19 an infection and fatality charges than different counties on common via Could 2020; the truth is, each outcomes have been decrease.
Counties that acquired extra passengers from Italy firstly of the pandemic skilled greater COVID-19 an infection and fatality charges. Particularly, a further 100 passengers from Italy arriving in a given county in the course of the fourth quarter of 2019 corresponded with a rise in each case and dying charges of about 5%.
Advantages of broader bans
Our preliminary outcomes counsel that vacationers coming from Italy drove the primary wave within the U.S. greater than these from China. Different researchers have linked the predominant pressure of virus in New York Metropolis early within the pandemic to Europe.
Primarily based on our proof, the comparatively early ban on journey from China seems to have been efficient in lowering instances and deaths.
In late January 2020, when Trump shut down flights from China, the virus could haven’t but unfold broadly sufficient amongst vacationers from China to considerably contribute to the early wave of the pandemic within the U.S. Ready till mid-March to impose a ban on journey from Europe, nevertheless, could have had lethal penalties.
The lesson: If a journey ban is warranted, time is of the essence.
Does that imply future bans will work?
Though our outcomes present robust proof that worldwide journey from Italy elevated the unfold of COVID-19 within the U.S. in the course of the first wave of the pandemic, this occurred at a time when folks have been largely unaware of the virus and the risk that it posed.
At present, with each vacationers and policymakers conscious of the risk, it’s unsure what impact worldwide journey would have on the unfold of COVID-19 within the U.S. On the similar time, new, extra transmittable strains of the virus improve the risk from worldwide journey. If the proof does warrant further journey restrictions, our analysis says to behave rapidly and suppose broadly.
The authors don’t work for, seek the advice of, personal shares in or obtain funding from any firm or group that might profit from this text, and have disclosed no related affiliations past their tutorial appointment.