Key Messages

  • As we wrestle with how best to mitigate COVID-19, it is imperative to concur on the likely main drivers of transmission (notably, infection clusters resulting from prolonged indoor respiratory exposure) in order to clearly explain risk and to determine the most effective, realistic behavioral and other means to reduce illness and mortality.

  • At the same time, we must avoid generating irrational fear and maintain a broader perspective, including assessing the possibility for substantial unintended consequences from the response to the pandemic.


In June 1981, when the first cases were reported of what became known as AIDS, I was living in the San Francisco Bay area. As the waves of death mounted, I volunteered at a hospice in Oakland, California, and later conducted epidemiological research at the University of California.

There are major differences between HIV and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and their resulting pandemics (AIDS and coronavirus disease ([COVID-19]). However, I’m having déjà vu: from the devastating number of deaths and the pervasive atmosphere of confusion, fear, and often panic.

Tragically, political leaders from Ronald Reagan to Nelson Mandela were slow to respond to the AIDS epidemic. All sides engaged in acrimonious ideological warfare that often ignored the epidemiological evidence. In hindsight, health authorities also made some decisions—especially under the pressure of needing to act immediately—that led to suboptimal and ultimately costly outcomes.1,2 Policies often became hardwired over time and difficult to walk back, even after new evidence appeared. Well-meaning but overly simplistic messages such as, “always use a condom with anyone or die” inadvertently created other problems.1,3,4 Earlier openness to innovative approaches, such as male circumcision and addressing sexual networks, could have saved many lives, particularly in sub-Saharan Africa.1,2,5 In subsequent years, as …