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  • Face Masks Required on Public Transportation and at Transportation Hubs

    As a result of a court order, effective immediately and as of April 18, 2022, CDC’s January 29, 2021 Order requiring masks on public transportation conveyances and at transportation hubs is no longer in effect. Therefore, CDC will not enforce the Order. CDC continues to recommend that people wear masks in indoor public transportation settings at this time.

  • Order Implementing Proclamation on Safe Resumption of Global Travel During the COVID-19 Pandemic

    CDC issued an Order to implement the President’s direction on safe resumption of global travel during the COVID-19 pandemic and provided guidance to airlines, other aircraft operators, and passengers in Technical Instructions and Frequently Asked Questions.

    All non-U.S.-citizen, non-immigrants, with limited exceptions, traveling to the United States by air must be fully vaccinated and show proof of vaccination.

  • Order Requiring Airlines to Collect Contact Information for All Passengers Arriving into the United States

    CDC issued an Order on October 25, 2021 requiring airlines and other aircraft operators to collect contact information for passengers before they board a flight to the United States from a foreign country. The purpose of collecting this information is to identify and locate passengers who may have been exposed to a person with a communicable disease for public health follow-up. Airlines will retain the information for 30 days and transmit the information to CDC upon request for contact tracing and public health follow-up to keep people safe.

  • Public Health Determination and Order Regarding the Right to Introduce Certain Persons from Countries Where a Quarantinable Communicable Disease Exists [534 KB, 30 pages]

    Following a public health determination, the CDC Director is terminating the Order under 42 U.S.C. §§ 265, 268 and 42 C.F.R. § 71.40 suspending the right to introduce certain persons into the United States. The implementation of the termination of the Order will be on May 23, 2022.

    CDC considered multiple factors in its public health assessment and finds that, at this time, the available COVID-19 mitigation tools, as well as the fact that 97% of the U.S. population lives in a county identified as having “low” COVID-19 Community Level, will sufficiently mitigate the COVID-19 risk for U.S. communities and make an order under 42 U.S.C. §§ 265, 268 and 42 C.F.R. § 71.40 no longer necessary. This Termination will be implemented on May 23, 2022, to enable the Department of Homeland Security (DHS) to implement appropriate COVID-19 mitigation protocols, such as scaling up a program to provide COVID-19 vaccinations to migrants, and prepare for full resumption of regular migration processing under Title 8 authorities.

    The initial CDC Order Suspending Introduction of Certain Persons from Countries where a Communicable Disease Exists was issued on 3/20/2020 [2.1 MB, 43 pages], extended on 4/22/2020 and extended and amended on 5/19/2020 [136 KB, 12 pages]. The Order was replaced with the Order Suspending the Right to Introduce Certain Persons from Countries Where a Quarantinable Communicable Disease Exists on 10/16/2020 and replaced again on 8/2/2021 [296 KB, 24 pages]. This Order and accompanying public health determination terminate all previous orders.

  • Public Health Reassessment and Immediate Termination of Order Suspending the Right to Introduce Certain Persons from Countries Where a Quarantinable Communicable Disease Exists with Respect to Unaccompanied Noncitizen Children [370 KB, 21 pages]

    During the COVID-19 pandemic, CDC issued an order suspending the right to introduce certain noncitizens attempting to enter the U.S. from Canada or Mexico (regardless of country of origin) at or between ports of entry. CDC has terminated the Order with respect to unaccompanied noncitizen children.

  • Almost exactly two years ago COVID-19 spread to the United States. Following the federalism model, the 50 states and their governors and legislators made many of their own pandemic policy choices to mitigate the damage from the virus. States learned from one another over time about what policies worked most and least effectively in terms of containing the virus while minimizing the negative effects of lockdown strategies on businesses and children.
    This study is an expanded and updated version of an October 2020 report card of how pandemic health, economy, and policy varied across the 50 states and the District of Columbia (Committee to Unleash Prosperity 2020). It examines three variables: health outcomes, economic performance throughout the pandemic, and impact on education.

    • Acknowledgements and Disclosures

      We wish to thank Jay Bhattacharya for his review of this study and his instructive advice. The views expressed herein are those of the authors and do not necessarily reflect the views of the National Bureau of Economic Research.


    WHO has been a particular casualty in the dispute about the origins of SARS-CoV-2. Former US President Donald Trump's verbal attacks and his decision to defund the agency drew blood in Geneva—and the wounds are still visible. The allegation that WHO shared responsibility for the pandemic by adopting a policy of appeasement towards China has proven impossible to refute. As a member-state organisation, WHO's staff are constitutionally bound to heed the instructions of the governments they serve. Only former Norwegian Prime Minister Gro Harlem Brundtland had the courage to defy countries when she was WHO Director-General during the first SARS outbreak in 2003. But although WHO has been injured, the truth is that the agency has been a convenient punchbag for western nations looking to distract attention away from their own mistakes and malfeasance. A fair-minded observer might conclude that WHO has done its best with a weak hand. Look at the facts.

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    In May, 2020, the World Health Assembly passed a resolution asking Director-General Tedros Adhanom Ghebreyesus to identify the source of the virus and its route of entry into human populations. A workplan was soon devised, experts were invited, and, by October, 2020, a team and its terms of reference had been finalised. Virtual meetings with Chinese colleagues started and the WHO-appointed scientists conducted field visits in China between Jan 14 and Feb 10, 2021. They took an explicitly one health approach—reconstructing the early part of the outbreak, identifying and mapping products sold at the Huanan seafood market, and testing livestock, wildlife, pets, and zoo animals for evidence of infection. Their report was published on March 30, 2021. Far from ignoring the possibility of a laboratory leak, the team cited it as one of four possible pathways for igniting the pandemic. They concluded that a laboratory leak was “extremely unlikely”, but they conceded that, although rare, laboratory accidents do happen, and especially so if laboratory protocols fell below acceptable safety thresholds. Critics of WHO argue that its scientists treated this investigation as an exercise in political diplomacy rather than rigorous science. The UK's The Sunday Times ran a front-page story in August, 2021, entitled “China, the WHO and the power grab that fuelled a pandemic”. Their claim was that the Chinese Government had infiltrated the agency, a takeover that “sowed the seeds of disaster”. This allegation is nonsense. Indeed, undeterred, phase two of WHO's investigation is already underway. A new team of 27 scientists has been appointed—the Scientific Advisory Group for the Origins of Novel Pathogens. Their mandate is to complete “an independent evaluation of all available scientific and technical findings…on the origins of SARS-CoV-2”. They will need to move quickly. The window of opportunity for discovering crucial evidence about the origins of the pandemic is closing fast.

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    The laboratory leak theory will continue to garner support as long as the Chinese Government refuses to allow an independent investigation of the institutions conducting coronavirus research in Wuhan. But the two theories— laboratory leak versus zoonotic spillover—are not in equipoise. Recent work strongly supports a central role for the Huanan market in the origin story of the pandemic. Michael Worobey is an evolutionary biologist at the University of Arizona. He has been part of a team seeking to track the earliest events in the spread of SARS-CoV-2. After carefully sifting through the published evidence, he concludes in a paper published in Science that the earliest case cluster of COVID-19 had no connection with the seafood market, while other presentations certainly did. He reminds us that in the first Lancet article describing the clinical features of COVID-19 a third of cases had no links to the market. He insists there is no contradiction here. The fact is that, in a city of 11 million people “there was a genuine preponderance of early COVID-19 cases associated with Huanan Market”. He emphasises the point—an “extraordinary preponderance”. For a highly transmissible virus that can spread asymptomatically it is not surprising that not all cases were directly connected to the market. The most likely origin of SARS-CoV-2 was someone who had direct contact with an infected live animal in the Huanan market. Proponents of a laboratory leak have so far provided no evidence to undermine this explanation.

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