The Covid-19 Riddle: Why Does the Virus Wallop Some Places and Spare Others?

[Celerity]

Experts are trying to figure out why the coronavirus is so capricious. The answers could determine how to best protect ourselves and how long we have to.

https://www.nytimes.com/2020/05/03/world/asia/coronavirus-spread-where-why.html?action=click&module=Spotlight&pgtype=Homepage

Iraqi border agents at the Zurbatiya border crossing with Iran. On the other side lies the largest epicenter of the virus in the Middle East. On the Iraqi side, there are relatively few cases. Credit...Ivor Prickett for The New York Times


The coronavirus has killed so many people in Iran that the country has resorted to mass burials, but in neighboring Iraq, the body count is fewer than 100. The Dominican Republic has reported nearly 7,600 cases of the virus. Just across the border, Haiti has recorded about 85. In Indonesia, thousands are believed to have died of the coronavirus. In nearby Malaysia, a strict lockdown has kept fatalities to about 100.

The coronavirus has touched almost every country on earth, but its impact has seemed capricious. Global metropolises like New York, Paris and London have been devastated, while teeming cities like Bangkok, Baghdad, New Delhi and Lagos have, so far, largely been spared. The question of why the virus has overwhelmed some places and left others relatively untouched is a puzzle that has spawned numerous theories and speculations but no definitive answers. That knowledge could have profound implications for how countries respond to the virus, for determining who is at risk and for knowing when it’s safe to go out again.

There are already hundreds of studies underway around the world looking into how demographics, pre-existing conditions and genetics might affect the wide variation in impact. Doctors in Saudi Arabia are studying whether genetic differences may help explain varying levels of severity in Covid-19 cases among Saudi Arabs, while scientists in Brazil are looking into the relationship between genetics and Covid-19 complications. Teams in multiple countries are studying if common hypertension medications might worsen the disease’s severity and whether a particular tuberculosis vaccine might do the opposite.

Many developing nations with hot climates and young populations have escaped the worst, suggesting that temperature and demographics could be factors. But countries like Peru, Indonesia and Brazil, tropical countries in the throes of growing epidemics, throw cold water on that idea. Draconian social-distancing and early lockdown measures have clearly been effective, but Myanmar and Cambodia did neither and have reported few cases. One theory that is unproven but impossible to refute: maybe the virus just hasn’t gotten to those countries yet. Russia and Turkey appeared to be fine until, suddenly, they were not.


Disinfecting streets in Yogyakarta, Indonesia, in mid-March.Credit...Ulet Ifansasti for The New York Times

snip