Thursday 19 March 2020

The WHO’s blind spot

In recent days with the threat of a complete lockdown in Australia, and already being extremely angry at the potential loss of public transport which I so love, as well as not being able to go to public libraries, there is one thing I have realised.

That is that the World Health Organization – who declared COVID-19 a pandemic eight days ago – has a major blind spot about the quarantine of international travellers.

Have a look at the final question on this extremely familiar (to me) Australian incoming passenger card:
Australian incoming passenger card. Note that there is no question about visiting South or East Asia, although that region’s ecology is more suitable to microbe growth than Africa or eastern South America
The question reads:
“Were you in Africa, South/Central America or the Caribbean in the last 6 days?”
The reason for this requirement is to exclude dangerous infectious diseases – mainly yellow fever – from Australia. Tropical Asia has never had yellow fever, which originated in prehistoric times from African monkeys and spread with slavery to tropical Latin America. Yellow fever was the first virus to be isolated – even before the invention of the electron microscope – and for this reason tropical Asia, even at much lower levels of development than today, successfully quarantined it.

Nonetheless, as Anthony Mills and Antoni Milewski showed in their ‘Does Life Consistently Maximise Energy Intensity’ – which celebrates its tenth anniversary this month – the most favourable environment for microbes is one with an abundance of catabolic nutrients. Catabolic nutrients are almost always chalcophile elements, which form covalent bonds with less electronegative nonmetals like carbon, phosphorus and sulfur. Because they are highly volatile and form dense sulfide minerals, chalcophile elements are, on Earth, bidirectionally depleted from the crust. They are depleted both by:
  1. core formation which is estimated to take up 99 percent of the dense chalcophile minerals
  2. evaporation into and from the atmosphere which loses the volatile chalcophiles to space
Within the crust chalcophile elements are intensely concentrated at plate boundaries where they can be uplifted from greater depths. Consequently, they are highly enriched in areas of high mountains, excluding mountains built from acidic igneous rocks, and further depleted on old tropical cratons.

If we follow Mills and Milewski’s criteria and add the requirement of hot or warm temperatures for microbial growth, tropical Asia, alongside Mesoamerica and Andean South America, becomes more favourable for microbial growth than less eutrophic Africa or non-Hispanophone South America. The humid subtropics of Asia and especially the hypereutrophic Pampas of South America also stand out as highly favourable for microbes.

Thus, even if yellow fever and other endemic infectious diseases are absent from tropical Asia, what COVID-19, and even SARS, does demonstrate is the need for quarantine of travellers exiting tropical and East Asia equal to that for those exiting Africa and Latin America. If travellers had been so quarantined when COVID-19 broke out, it would not have spread into communities outside China.

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