CMAAO CORONA FACTS and MYTH BUSTER 83
791: A coronavirus Mystery Riddle: Why Some Places fare Better
Adapted from an article in New York Times
Dr K K Aggarwal
President Confederation of Medical Associations of Asia and Oceania, HCFI, Past National President IMA, Chief Editor Medtalks
Variable Death Rates: World: 7 %; Europe: 9.7 %; North America: 5.82 %, South America: 5.1%; Africa: 3.91%; Asia 3.51%; India: 3.27 %; Oceania 1.36%
Variable Deaths per Million Population: Spain: 540, USA: 207, Europe: 131; North America: 43, World: 31.8, India: 1; India, Pakistan, Nepal, Sri Lanka, Bangladesh: 0.7,
Asia: 5.7 (11 countries average 0.44; 10 countries average 1.6; 11 countries average 3.9; 3 countries average 9.6 and 3 countries (Israel, turkey, Iran) average 41.3)
The coronavirus has touched 112 countries, but its impact has been uneven. 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.
New York: 323,883 cases, 24648 deaths, 16509 cases per million population, 1256 deaths per million population
London: More than 24700 cases and 5156 deaths, ONS analysis shows there were 55 deaths for every 100,000 people in the poorest parts of England, compared with 25 in the wealthiest areas.
Thailand: 2969 total cases with 54 Deaths
Iraq: 2296 cases with 54 Deaths
Nepal 75 cases with no death
The question of why the virus has overwhelmed some places and left others relatively untouched is a puzzle. Each possible explanation seems to come with caveats and counterevidence.
If older people are highly vulnerable, for instance, Japan, with its aging population, should be devastated. But it has 14,877 cases with only 487 deaths.
Is it genetics, Saudi Arabia is studying genetic differences and Brazil is looking into the relationship between genetics and Covid-19 complications.
If common hypertension medications might worsen the disease’s severity and whether BCG or Leprosy vaccine (Mycobacterium W), not vaccinated with H1N1 flu vaccine, current Polio vaccine might do the opposite.
Many developing nations with hot climates and young populations have escaped the worst but countries like Peru (45928 cases 1286 deaths), Indonesia (11,192 cases and 845 deaths) and Brazil (101,147 cases and 7025 deaths) have growing epidemics. Maybe the virus just hasn’t gotten to those countries yet. Russia (134,687 cases with 1280 deaths) and Turkey (126,045 cases and 3397 deaths) appeared to be fine until, suddenly, they were not.
The Spanish flu that broke out in the United States in 1918 seemed to die down during the summer only to come roaring back with a deadlier strain in the fall, and a third wave the following year. It eventually reached far-flung places like islands in Alaska and the South Pacific and infected a third of the world’s population.
Low testing may be the reason for underestimation of virus’s progress, and deaths. But still mass burials or hospitals turning away sick people by the thousands would be hard to miss, and a number of places are just not seeing them.
Possible answers: Virus, Demographics, Culture, Environment and the Speed of Government Responses.
1. SARS 2 virus is different from SARS 1 virus, as its infectivity start much earlier
2. It mutates slowly than H1N1 virus
3. Over ten strains of the virus are circulating in the atmosphere, may have different lethality
4. Phylogenetic analysis of 30 publicly available SARS-CoV-2 samples concluded that emergence of SARS-CoV-2 in the human population likely occurred in Mid November 2019
5. There are different clades of SARS-CoV-2 developing as COVID-19 spread across the globe.13 Different clades emerge as viruses evolve. This is entirely normal and does not mean there are new strains of SARS-CoV- 2 that are more pathogenic than others circulating right now
6. Contact time: Significant exposure to Covid-19: face-to-face contact within 6 feet with a patient with symptomatic Covid-19 that is sustained for at least a few minutes (and some say more than 10 minutes or even 30 minutes). The chance of catching Covid-19 from a passing interaction in a public space is minimal.
Aging and the power of youth
If an aging population is the most vulnerable, for instance, Japan should be at the top of the list. It is far from it.
Many countries that have escaped mass epidemics have relatively younger populations. Young people are more likely to contract mild or asymptomatic cases that are less transmissible to others. And they are less likely to have high risk comorbid diseases.
Africa has 45380 cases as on today, a tiny fraction of its 1.3 billion people, is the world’s youngest continent, with more than 60 percent of its population under age 25.
But in Thailand and Najaf, Iraq the 20-to-29 age group had the highest rate of infection but often showed few symptoms. By contrast, the national median age in Italy, one of the hardest hit countries, is more than 45. The average age of those who died of Covid-19 there was around 80.
Younger people tend to have stronger immune systems, which can result in milder symptoms.
In Singapore and Saudi Arabia, most of the infections are among foreign migrant workers, many of them living in cramped dormitories. However, many of those workers are young and fit, and have not required hospitalization.
Along with youth, relative good health can lessen the impact of the virus among those who are infected, while certain pre-existing conditions — notably hypertension, diabetes and obesity — can worsen the severity.
Japan, with the world’s oldest average population, has recorded only 487 deaths, although its caseload has risen with increased testing.
The Guayas region of Ecuador, the epicenter of an outbreak that may have claimed up to 7,000 lives, is one of the youngest in the country, with only 11 percent of its residents over 60 years old.
Also, some young people who are not showing symptoms are also highly contagious for reasons that are not well understood.
In a HCFI study in India density of the population was found to be inversely proportional to the number of COVID cases. In states with average population density of 1185 /sk km the average number of cases was 2048.
And in states with population density of 909/ sk km the number of cases was 34.6. In these when Chandigarh and Pondicherry (high population density with strict discipline) were taken out the average density of other states was 217/ sq Km with average number of cases only 35.
Cultural factors, like the social distancing (physical distancing with intact emotional distancing) may give some countries more protection.
In Thailand and India, where virus numbers are relatively low, people greet each other at a distance with namaste. In Japan and South Korea, people bow, and long before the coronavirus arrived, they tended to wear face masks when feeling unwell. But in Iraq and the Persian Gulf countries, men often embrace or shake hands on meeting, yet most are not getting sick.
In developing world, the custom of caring for the elderly at home leads to fewer nursing homes, which have been tinder for tragic outbreaks in the West.
National distancing has also proven advantageous. Countries that are relatively isolated have reaped health benefits from their seclusion.
Far-flung nations, such as some in the South Pacific and parts of sub-Saharan Africa, have not been as inundated with visitors bringing the virus with them. In Africa limited travel from abroad is perhaps the main reason for the continent’s relatively low infection rate.
Countries that are less accessible for political reasons, like Venezuela, or because of conflict, like Syria and Libya, have also been somewhat shielded by the lack of travelers, as have countries like Lebanon and Iraq, which have endured widespread protests in recent months.
The lack of public transportation in developing countries may have also reduced the spread of the virus there.
Heat and Light
The geography of the outbreak — which spread rapidly during the winter in temperate zone countries like Italy and the United States and was virtually unseen in warmer countries such as Chad or Guyana — seemed to suggest that the virus did not take well to heat. Other coronaviruses, such as ones that cause the common cold, are less contagious in warmer, moist climates.
But Some of the worst outbreaks in the developing world have been in places like the Amazonas region of Brazil, as tropical a place as any.
The virus that causes Covid-19 appears to be so contagious as to mitigate any beneficial effect of heat and humidity. But other aspects of warm climates, like people spending more time outside, could help.
People living indoors within enclosed environments may promote virus recirculation, increasing the chance of contracting the disease.
The ultraviolet rays of direct sunlight inhibit this coronavirus. So surfaces in sunny places may be less likely to remain contaminated.
No scientist has proposed that beaming light inside an infected person would be an effective cure.
Early and Strict Lockdowns
Countries that locked down early, like India, Vietnam and Greece, have been able to avoid out-of-control contagions, evidence of the power of strict social distancing and quarantines to contain the virus.
In Africa, countries with bitter experience with killers like H.I.V., drug-resistant tuberculosis and Ebola reacted quickly.
Airport staff from Sierra Leone to Uganda were taking temperatures (since found to be a less effective measure) and contact details and wearing masks long before their counterparts in the United States and Europe took such precautions.
Senegal and Rwanda closed their borders and announced curfews when they still had very few cases. They also began contact tracing early.
Sierra Leone repurposed disease-tracking protocols that had been established in the wake of the Ebola outbreak in 2014, in which almost 4,000 people died there. The government set up emergency operations centers in every district and recruited 14,000 community health workers, 1,500 of whom are being trained as contact tracers, even though Sierra Leone has only about 155 confirmed cases.
Uganda, which also suffered during the Ebola contagion, quickly quarantined travelers from Dubai after the first case of coronavirus arrived from there. Authorities also tracked down about 800 others who had traveled from Dubai in previous weeks.
The Ugandan health authorities are also testing around 1,000 truck drivers a day. But many of those who test positive have come from Tanzania and Kenya, countries that are not monitoring as aggressively, leading to worries that the virus will keep penetrating porous borders.
Lockdowns, with bans on religious conclaves and spectator sporting events, clearly work.
More than a month after closing national borders, schools and most businesses, countries from Thailand to Jordan have seen new infections drop.
In the Middle East, the widespread shuttering of mosques, shrines and churches happened relatively early and probably helped stem the spread in many countries.
A notable exception was Iran, which did not close some of its largest shrines until March 18, a full month after it registered its first case in the pilgrimage city of Qum. The epidemic spread quickly from there, killing thousands in the country and spreading the virus across borders as pilgrims returned home.
As effective as lockdowns are, in countries lacking a strong social safety net and those where most people work in the informal economy, orders closing businesses and requiring people to shelter in place will be difficult to maintain for long. When people are forced to choose between social distancing and feeding their families, they are choosing the latter.
Counter-intuitively, some countries where authorities reacted late and with spotty enforcement of lockdowns appear to have been spared. Cambodia and Laos both had brief spates of infections when few social distancing measures were in place but neither has recorded a new case in about three weeks.
Lebanon, whose Muslim and Christian citizens often go on pilgrimages respectively to Iran and Italy, places rife with the virus, should have had high numbers of infections. It has not.
The answer is likely to be some combination of the above factors combined with sheer luck.
Also, countries with the same culture and climate could have vastly different outcomes if one infected person attends a crowded social occasion, turning it into what researchers call a super-spreader event. That happened when a passenger infected 634 people on the Diamond Princess cruise ship off the coast of Japan, when an infected guest attended a large funeral in Albany, Ga., and when a 61-year-old woman went to church in Daegu, South Korea, spreading the disease to hundreds of congregants and then to thousands of other Koreans.
Because an infected person may not experience symptoms for a week or more, if at all, the disease spreads under the radar, exponentially and seemingly at random. Had the woman in Daegu stayed home that Sunday in February, the outbreak in South Korea might have been less than half of what it is.
Thailand reported the first confirmed case of coronavirus outside of China in mid-January, from a traveller from Wuhan, the Chinese city where the pandemic is thought to have begun. In those critical weeks, Thailand continued to welcome an influx of Chinese visitors. For some reason, these tourists did not set off exponential local transmission.
Also have India closed the International borders or started screening the International visitors, when they detected the first case in Kerala on 30th January, the situation would have been different.
On the contrary the Jamatis were responsible for number of cases in Malaysia, Pakistan and India.
And when countries do all the wrong things and still end up seemingly not as battered by the virus as one would expect, we have no answer. The classical case of celebrity Kanika Kapoor in India who attended the party of hundreds and did not cross infected a single one will remain a mystery.