Social distancing more important than lockdowns in COVID-19 fight - TAU

"Extreme restrictions are uncalled for. What we need is fast implementation of social distancing.”

The Western Wall plaza has been divided into prayer sections to comply with restrictions on gathering outside. May 05, 2020 (photo credit: OLIVIER FITOUSSI/FLASH90)
The Western Wall plaza has been divided into prayer sections to comply with restrictions on gathering outside. May 05, 2020
(photo credit: OLIVIER FITOUSSI/FLASH90)
Research from Tel Aviv University comparing cellphone mobility data and COVID-19 mortality data released on Tuesday could have far-reaching policy implications, since it seems to show timely social distancing rather than the severity of lockdown restrictions is the key factor in reducing the spread of and mortality from the coronavirus.
The peer-reviewed paper, which was accepted for publication in EMBO Molecular Medicine, compared data collected from the cellphones of iPhone users (Apple Mobility Data) to COVID-19 mortality data and found that the date on which social distancing began in different OECD countries is the best predictor of the mortality rate relative to the size of the population – with a delay of 7.49 days doubling the number of fatalities. In contrast, no statistical correlation was found between the number of fatalities and the duration, severity or even total lack of a lockdown in each country.

The study was conducted by Prof. Tal Pupko, head of the Shmunis School of Biomedicine and Cancer Research, in collaboration with Prof. Itay Mayrose and research students Gil Loewenthal, Shiran Abadi, Oren Avram, Keren Halabi, Noa Ecker and Nathan Nagar of TAU’s Faculty of Life Sciences.
 
“Mobility data indicate that a hermetic lockdown, in which everyone must stay at home, is unnecessary. Instead, social distancing measures should be introduced as early as possible,” say Pupko and Mayrose. “We have shown that the countries with the lowest mortality rates in the first outbreak of COVID-19 were not those that imposed the most hermetic lockdowns, but rather those in which mobility decreased (even slightly) at an early stage... as the government considers tightening [Israel’s second lockdown] even further, the import of our research is clear: Extreme restrictions are uncalled for. What we need is fast implementation of social distancing.”
 
In their study, the researchers collected cellular data that reflected the extent of mobility on a specific day in each OECD country, then normalized the data to the size of the population and typical mobility patterns in that country. For example, in wintertime, people in cold countries like Sweden don’t go out as much as people in Israel. The researchers obtained a mobility indicator for every country in regular times: the average number of citizens who travel by vehicle every day. Starting in March 2020, they found a decrease in mobility in all countries. However, this reduction varies from one country to another in accordance with the steps taken, from social distancing in Sweden, to hermetic lockdowns in countries like Italy, Spain and Israel.

Researchers Avram, Abadi and Loewenthal elaborated: ”We would have expected to see fewer COVID-19 fatalities in countries with a tighter lockdown, but the data reveal that this is not the case. This means that Israel could have reached the same mortality rate with a lockdown that was less economically and socially lethal – in the first round and probably in the present outbreak as well.”

The mobility data indicate, for example, that both the time it took to respond to the pandemic and the severity of the lockdown were similar in Israel and in the Czech Republic. And even though Israel’s lockdown was longer — manifested in lower mobility for a longer period of time — the ultimate mortality rates remained similar. In another example, the Spanish lockdown was longer and tighter than the French, but when it ended, mortality rates in both countries were about the same.

“We found that an early implementation of social distancing is the most significant factor, with a very high correlation to the mortality rate,” said the researchers. “Countries that responded quickly with social distancing measures – not necessarily with a tight lockdown – ultimately emerged from the first outbreak with better results. In contrast, no correlation was found between mortality data and the severity and/or length of the lockdown. Even in Sweden, a country that never imposed a lockdown, we can see that the early decrease in mobility, starting in March, was manifested in the mortality rate. Our study is based purely on observations and does not relate to the premises of any existing epidemiological model. We show that the spread of the pandemic can be prevented by quickly implementing basic measures of social distancing – without a rigorous lockdown.”