“Monitoring travelers was labor-intensive and limited by incomplete information, volume of travelers, and potential for asymptomatic transmission,” the report said. “Health departments need to weigh the resources needed for monitoring against those needed for implementing mitigation activities during the COVID-19 pandemic.”
According to the report, between Feb. 3 and Mar. 17, California officials received, corrected, and transmitted information on 11,574 travelers to local health jurisdictions for follow-up. The report said three travelers were matched to three of the 26,182 patients with COVID-19 reported to California by April 15.
The report said more efficient methods of collecting passenger data, such as transferring flight manifests electronically from airlines to federal officials who could then provide the information to states, would help local health boards quickly reach out to travelers at risk. And that, in turn, would lead to timely testing, case identification and the faster launching contact tracing investigations, according to the CDC.
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International travel also factored into the early spread of the disease in Massachusetts, when a
Biogen leadership conference in Boston in late February drew about 175 company executives from locations around the United States and the world to the Marriott Long Wharf Hotel.
At least 99 people — some who attended a Biogen leadership meeting on Feb. 26 and 27, and others who had contact with them afterward — were later confirmed to have caught the virus.
Biogen announced last month that it had joined a consortium that plans to build a collection of biological and medical data about the virus.
“The COVID-19 pandemic has had a very direct, very personal impact on our Biogen community,” said Dr. Maha Radhakrishnan, chief medical officer for Biogen, at the time of the April announcement. “We are uniquely positioned to contribute to advancing COVID-19 science in an organized and deliberate way so we can all gain a better understanding of this virus."
Calif. health officials encountered difficulty tracking international travelers at start of coronavirus pandemic, CDC says - The Boston Globe