The timeline of coronavirus infection in the United States was extended as the new information released by Santa Clara county in U.S. state of California on Tuesday showed that a 57-year-old San Jose woman died at home to the COVID-19 on Feb. 6, over 20 days earlier than previously known first coronavirus death on the U.S. soil.

Given that the woman and another 69-year-old man who died at home on Feb. 17 have no "significant travel history," some U.S. experts said that community transmission of the virus in the United States may have started as early as mid-January or even the beginning of January.

January was the time when the common flu season still haunting the United States, therefore, before the COVID-19 pandemic tensed the American nerves, it's hard to say how big a death toll of coronavirus had been written under the flu account.

The U.S. Centers for Disease Control and Prevention have estimated that over the winter between 2019-2020, there were at least 22 million illnesses, 210,000 hospitalizations and 12,000 deaths from the flu.

However, truth will come to light sooner or later. U.S. CDC Director Robert Redfield admitted on March 11 when testifying to the U.S. Congress that some Americans who seemingly died of influenza tested positive for the novel coronavirus in a posthumous diagnosis.

The hidden community spread in California now makes the picture more vague. When did the coronavirus first attack the U.S. soil? How many people in the country are infected with the deadly virus? How transparent are the U.S. data on the COVID-19 pandemic?

More questions are waiting for answers as the timeline of the outbreak on U.S. soil remained unclear and it is still difficult to verify different data of the pandemic in the United States given the government's lagging virus testing.

The California information is just a tip of the iceberg. Will there be much greater numbers of infections beneath the water?

California Governor Gavin Newsom has announced the authority will perform more autopsies on individuals suspiciously died from the coronavirus since December. What kind of findings will be unveiled? The international community is waiting to see.

Addicted to smear China, those China Hawks in the United States have recently attacked China's anti-epidemic efforts by various means, including on the transparency of the Chinese epidemic data. However, the truth is that the U.S. account of the COVID-19 outbreak on its soil has never been clear.

A report on viral antibodies by Stanford researchers showed on April 17 that the true number of COVID-19 cases in California's Silicon Valley is at least 50 times higher than the official figure.

Due to the flawed and inadequate testings, the exact number of the infections that can be fully trusted remains a question. New York health authorities have recently said that the present number of around 140,000 confirmed cases may be far less than the real number.

Alarms of massive infections have been set off by medical officials and experts in early days of the outbreak, but the U.S. administration did not take them seriously and even played down the disease at the beginning.

Making clear the timeline of COVID-19 outbreak in the United States will help sort the COVID-19 deaths out from its flu deaths and offers lessons for the White House and state governments to better prepare for other similar crisis.

Making clear the timeline of COVID-19 outbreak in the United States is also significant to the global fight against the virus, because scientists across the world need more real information to detect the spread of the virus and thus to predict the change of the virus in the future.

The coronavirus pandemic is not the only public health crisis facing humankind and it definitely will not be the last. In a world that all countries have a shared future, no one can simply or thoroughly shut the epidemic out his or her own doors when it is not controled on a global level.

It's hoped the United States can complete the jigsaw puzzle of its COVID-19 timeline at an early date to meet the expectations of the U.S. people and the international community.