A study released on Sunday night found that some 70 percent of coronavirus cases in Israel originated with people entering from the United States, Channel 12 reported.
Researchers at the University of Tel Aviv based their findings on an analysis of the genetic data of people infected with COVID-19 and their movements. After the U.S., European countries were the second most important point of origin, with France and Belgium at the top of the list.
Surprisingly, almost none of the cases were traced to China, though a small percentage came from the Philippines and Russia.
According to the study, a mere five percent of those who carried the infection with them, and apparently did not comply with isolation rules, caused 80 percent of the infections in Israel as they moved about inside the country.
Dr. Edi Stern, who led the research team, attributed the result to the fact that Israel only began restricting flights from the U.S. 39 days after it banned Chinese flights, allowing infecting travelers into the country.
Dr. Stern stressed that the main lesson to be learned is that containment of the pandemic depends first of all on closing borders, and after that, quarantines.