Covid Chronicles (3)

Covid19 has shone light on two spokespersons in the USA: Dr Antony Fauci and Dr Deborah Birx. Both are known for their work in the HIV-AIDS epidemic, the other major viral scourge of our time.

It is tempting to draw parallels between HIV-AIDS and Covid19. It is understandable too.

Caution however is advisable.

Viral origins, viral mutation characteristics, and similarities in human immune response are but one part of the story. How the viruses spread, and how they seem to affect people quite differently depending on their age, gender, pre-existing conditions, and ethnicity are important to understand too. That is why epidemiologists are crucial players in this complex story.

For the contagious disease, there is understandable interest in “spreaders” and “superspreaders“, and the settings where they are most effective at spreading. Unlike in other epidemics, where a 20/80 heuristic held, Covid19 seems to be more like a 10/90 phenomenon so far.

Back to HIV-AIDS.

Randy Shilts’s doorstopper of a book And The Band Played On is an accessible, solid piece of investigative reporting on what happened in the 1980s as AIDS spread in the United States. The book casts an eye on the role played by the gay community, the healthcare providers, the CDC, and the media as the crisis unfolded. In a rough summary, the gay community got vilified (it is not commonly known that AIDS was first named GRID – gay related immune deficiency) but also did a lot to raise money and draw attention to the phenomenon; the healthcare providers were at the coal face and the first to see the development and spread of the disease, and emergent heroes; the CDC faced considerable government apathy and political infighting both within their own institution and within the government; and media reporting was variable, with the prevailing prejudice of homophobia.

I read the book years ago while looking for complex health policy challenges to sink my teeth into for my doctoral work. I thought about the book often these last few months as Covid19 raged and then finally dug it out from the back of my bookcases to re-read.

For what we are seeing unfolding now in 2020 with Covid19 is not that different — not least the CDC in the USA being headed by a person with a history of having called for faith-based and not medical approaches to HIV-AIDS.

What of superspreaders then?

In the HIV-AIDS story in the USA, a Canadian flight attendant named GaĆ«tan Dugas was identified as “patient zero” and linked with at least 40 of the first 248 cases reported, the “setting” being San Francisco bathhouses frequented by gay men. Identifying him as “patient zero” has subsequently been disputed.

Unlike HIV-AIDS, Covid19 is not sexually transmitted, which means the settings for superspreading could be public and diverse e.g. fitness classes, choir practice, religious congregations. The poorly ventilated London Tube, normally packed regardless of the hour of the day, suddenly is high risk. Without a track-and-trace programme such as deployed by the CDC during the HIV-AIDS crisis, it will be tricky to identify superspreaders of Covid19.

What does this mean for us and our own safety? How do we assess risk to ourselves? Do we continue to eschew large gatherings? Do we avoid enclosed spaces? Do we minimise any social contact at all? Or do we just avoid the social butterflies amongst our friends? What if we ourselves are a risk to others? What if we are superspreaders, just not aware of it because the asymptomatic state can last a while?

We know something about risk assessment in various settings. But not always about how to reduce risks. Here is a helpful visual.

(Created by epidemiologists Ellie Murray and Julia Marcus)

Unless we know more about specific individual risks, perhaps we would do well to remember and practise all of the above, even at the risk of “being boring”.