05/03/2020 - 19:16
- Clarín.com
- The New York Times International Weekly
By Hannah Beech, Alissa J. Rubin, Anatoly Kurmanaev, and Ruth Maclean
The coronavirus has killed so many people in Iran that the country has resorted to mass burials, but in neighboring Iraq, the number of bodies is less than 100.
The Dominican Republic has reported almost 7,600 cases of the virus. Just across the border, Haiti has registered about 85.
In Indonesia, thousands of people are believed to have died from the coronavirus. In nearby Malaysia, a strict blockade has kept deaths at around 100.
The coronavirus has touched almost every country on earth, but its impact has seemed capricious. Global metropolises such as New York, Paris, and London have been devastated, while populous cities such as Bangkok, Baghdad, New Delhi, and Lagos have been largely spared so far.
The question of why the virus has overwhelmed some places and left others relatively intact is a puzzle that has given rise to numerous theories and speculations, but not definitive answers. That knowledge could have profound implications for how countries respond to the virus, to determine who is at risk, and to know when it is safe to re-emerge.
Sanitizing streets in Yogyakarta, Indonesia in mid-March. (Ulet Ifansasti for The New York Times)
There are already hundreds of ongoing studies around the world investigating how demographics, pre-existing conditions, and genetics could affect wide variation in impact.
Saudi Arabian doctors are studying whether genetic differences may help explain the varying levels of severity of COVID-19 cases among Saudi Arabs, while scientists in Brazil are studying the relationship between genetics and COVID complications. -19. Teams from various countries are studying whether common hypertension medications could worsen the severity of the disease and whether a given tuberculosis vaccine could do the opposite.
Many developing nations with hot climates and young populations have escaped the worst, suggesting that temperature and demographics may be factors . But countries like Peru, Indonesia and Brazil, tropical countries in the midst of growing epidemics, pour cold water on that idea.
Draconian social distancing and early closure measures have been clearly effective, but Myanmar and Camboy did neither, and have reported few cases.
The Imam Ali Shrine in Najaf, Iraq. Najaf youth had the highest infection rate but few symptoms. (Ivor Prickett for The New York Times)
A theory that has not been proven but is impossible to refute: Perhaps the virus has not yet reached these countries . Russia and Turkey seemed fine until, suddenly, they were not.
Time may still be the biggest equalizer: The Spanish flu that broke out in the United States in 1918 seemed to die out over the summer, only to return with a deadlier strain in the fall and a third wave the following year. Eventually it reached far-flung places like Alaska Islands and the South Pacific, infecting a third of the world's population.
"We are at a very early stage in this disease," said Dr. Ashish Jha, director of the Harvard Institute for Global Health Research. "If this were a baseball game, it would be the second inning, and there is no reason to think that for the ninth inning the rest of the world that now seems unaffected will not become something like other places."
Doctors studying infectious diseases around the world say they do not yet have enough data to get a complete epidemiological picture, and that information gaps in many countries make it dangerous to draw conclusions. The tests are deplorable in many places, leading to a huge underestimation of the progress of the virus, and the deaths are almost certainly not counted.
However, the general guidelines are clear. Even in places with poor records and broken health systems, mass burials or hospitals that reject thousands of sick people would be hard to ignore, and in several places they just are n't seeing them, at least not yet.
Interviews with more than two dozen infectious disease experts, health officials, epidemiologists, and academics from around the world suggest four main factors that could help explain where the virus thrives and where it does not: demographics, culture, the environment and the speed of government responses.
Every possible explanation comes with considerable caveats and confusing counter-evidence. If an aging population is the most vulnerable, for example, Japan should be at the top of the list. It is far from it. However, these are the factors that experts find most persuasive.
The power of youth
Many countries that have escaped massive epidemics have relatively younger populations .
Young people are more likely to develop mild or asymptomatic cases that are less communicable to others, said Robert Bollinger, professor of infectious diseases at the Johns Hopkins School of Medicine. And they are less likely to have certain health problems that can make coronavirus disease COVID-19 particularly deadly, according to the World Health Organization.
Africa - with some 45,000 reported cases, a small fraction of its 1.3 billion inhabitants - is the youngest continent in the world, as more than 60% of its population is under the age of 25. In Thailand and Najaf (Iraq), local health authorities found that the 20-29 age group had the highest infection rate, but often had few symptoms.
Passengers seated according to social distancing protocol on a train in Bangkok, Thailand (Adam Dean for The New York Times)
In contrast, the national average age in Italy, one of the most affected countries, is over 45 years. The median age of those who died from COVID-19 was about 80 years.
Younger people tend to have stronger immune systems, which can lead to milder symptoms, said Josip Car, a population and global health expert at Nanyang University of Technology in Singapore.
In Singapore and Saudi Arabia, for example, most infections occur among foreign migrant workers , many of whom live in narrow community 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 infected, while certain pre-existing conditions - notably hypertension, diabetes and obesity - can worsen the severity, researchers in the United States say.
There are notable exceptions to demographic theory. Japan, with the world's oldest average population, has recorded fewer than 520 deaths, although its number of cases has increased with increasing testing.
The Guayas region in Ecuador, epicenter of an outbreak that may have claimed up to 7,000 lives, is one of the youngest in the country, with only 11% of its residents over the age of 60.
And Harvard's Jha cautions that some young people who don't show symptoms are also highly contagious for reasons not well understood.
Cultural distance
Cultural factors, such as the social distancing that occurs in certain societies, may give some countries more protection, according to epidemiologists.
In Thailand and India, where the number of viruses is relatively low, people greet each other from a distance , with their palms together as in a sentence. In Japan and South Korea, people bow, and long before the coronavirus arrived, they tended to wear face masks when they felt bad.
In much of the developing world, the custom of caring for the elderly at home leads to fewer asylums, which have been an obstacle to tragic outbreaks in the West.
However, there are notable exceptions to the theory of cultural distancing. In many parts of the Middle East, such as Iraq and the Persian Gulf countries, men often hug or shake hands when they meet, but most do not get sick.
What might be called " national distancing " has also been shown to be advantageous. Countries that are relatively isolated have reaped health benefits from their seclusion.
A checkpoint in Kampala, Uganda, in early April. . (Sumy Sadurni / Agence France-Presse - Getty Images)
Distant nations, such as some in the South Pacific and parts of sub-Saharan Africa, have not been so inundated with visitors that they carry the virus with them. Africa's health experts cite limited travel from abroad as the main possible reason for the continent's relatively low infection rate.
Countries that are less accessible for political reasons, such as Venezuela, or because of conflicts, such as Syria and Libya, have also been somewhat protected by the lack of travelers, as have countries such as Lebanon and Iraq, which have endured widespread protests in recent months.
Lack of public transportation in developing countries may also have reduced the spread of the virus there.
Heat and Light
The geography of the outbreak - which spread rapidly during winter in temperate zone countries like Italy and the United States and was virtually invisible in warmer countries like Chad or Guyana - seemed to suggest that the virus was not well adapted to heat. Other coronaviruses, such as those that cause the common cold, are less contagious in warmer, more humid climates.
But the researchers say the idea that warm weather alone can repel the virus is an illusion.
Some of the worst outbreaks in the developing world have occurred in places like the Amazon region of Brazil, a place as tropical as any other.
"The best guess is that summer conditions will help, but they alone are unlikely to lead to a significant slowdown in growth or a decrease in cases," said Marc Lipsitch, director of the Center for Communicable Disease Dynamics at the University from Harvard.
Central Seoul, South Korea, in March. A single event could have fueled the spread of the virus in the country. (Woohae Cho for The New York Times)
The virus that causes COVID-19 appears to be so contagious as to mitigate any beneficial effects of heat and humidity, said Dr. Raúl Rabadan, a computer biologist at Columbia University.
But other aspects of hot weather, like people spending more time outside, may help.
"People who live indoors in closed environments can promote virus recirculation, increasing the chance of contracting the disease," said Car of Nanyang University of Technology.
The ultraviolet rays of sunlight directly inhibit the coronavirus, according to a study of ecological modelers at the University of Connecticut. Therefore, surfaces in sunny locations may be less likely to remain contaminated, but transmission usually occurs through contact with an infected person, not by touching a surface.
No scientist has proposed that emitting light inside an infected person, as President Donald Trump has suggested , is an effective cure. And tropical conditions may have even reassured some people in a false sense of security.
"People were saying, 'It's hot in here; nothing will happen to me,' " said Dr. Doménica Cevallos, a medical researcher in Ecuador. "Some even went out on purpose to sunbathe, thinking it would protect them from infection."
Strict and early quarantines
Countries that closed early, such as Vietnam and Greece, have been able to avoid out-of-control infections, demonstrating the power of strict social distancing and quarantines to contain the virus.
In Africa, countries with a bitter experience with killers such as HIV, drug-resistant tuberculosis and Ebola knew the situation and reacted quickly.
Airport staff from Sierra Leone to Uganda were taking temperatures (which have since turned out to be a less effective measure) and contact details and wearing masks long before their counterparts in the United States and Europe took those precautions.
Senegal and Rwanda closed their borders and announced curfews when they still had very few cases. The ministries of health began to locate the contacts promptly.
All of this occurred in a region where ministries of health had become dependent on money, staff and supplies from foreign donors, many of whom had to pay attention to outbreaks in their own countries, said Catherine Kyobutungi, director. executive of the African Center for Population and Health Research.
"The countries wake up one day and say, 'Okay, the weight of the country falls on our shoulders, so we have to step forward,'" he said.
"And they have. Some of the responses have been beautiful to behold, honestly."
Sierra Leone again proposed the disease monitoring protocols that had been established after the Ebola outbreak in 2014, in which nearly 4,000 people died. The government established emergency operations centers in all districts and recruited 14,000 community health workers, 1,500 of whom are being trained as contact trackers , although Sierra Leone has only about 155 confirmed cases.
However, it is unclear who will pay their wages or expenses such as motorcycles and raincoats to keep them running during the upcoming rainy season.
Uganda, which also suffered during the Ebola spread, quickly quarantined travelers from Dubai after the first coronavirus case came from there. Authorities also located 800 others who had traveled from Dubai in the previous weeks.
Uganda's health authorities are also examining about 1,000 truckers a day. But many of those who test positive have come from Tanzania and Kenya, countries that are not tracking as aggressively, raising fears that the virus will continue to penetrate porous borders .
The closings, with bans on religious conclaves and spectator sporting events, clearly work, says the World Health Organization. More than a month after closing national borders, schools, and most businesses, countries from Thailand to Jordan have seen new infections decrease.
In the Middle East, the widespread closure of mosques, shrines, and churches occurred relatively soon, and likely contributed to curbing 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 recorded its first case in the pilgrimage city of Qum. The epidemic spread rapidly from there, killing thousands of people in the country and spreading the virus across borders when pilgrims returned home.
As effective as closures are, in countries that lack a strong social safety net and in those where most people work in the informal economy, it will be difficult to sustain long-term requests for company closings and the need for people to take refuge in one place . When people are forced to choose between social distancing and feeding their families, they are choosing the latter.
Contrary to what one would believe, some countries in which the authorities reacted late and with an irregular application of the closings seem to have been saved. Both Cambodia and Laos had brief periods of infection when few social distancing measures were applied, but neither has registered a new case in about three weeks.
Lebanon, whose Muslim and Christian citizens often go on pilgrimage to Iran and Italy respectively, places where the virus is rife, should have had a high number of infections. It has not.
"We just didn't see what we expected," said Dr. Roy Nasnas, an infectious disease consultant at Geitaoui University Hospital in Beirut. "We do not know why".
Throwing the dice
Finally, most experts agree that there may not be a single reason for some countries to be hit and others not. The answer is likely to be some combination of the factors mentioned above, as well as another one mentioned by the researchers: pure luck.
Countries with the same culture and climate could have very different results if an infected person attends a massive social event, turning it into what researchers call a super-diffusing event.
That happened when a passenger infected 634 people on the Diamond Princess cruise off the coast of Japan, when an infected guest attended a grand funeral in Albany, Georgia, and when a 61-year-old woman went to church in Daegu, Korea. South, spreading the disease among hundreds of parishioners and then thousands of other Koreans.
Because an infected person may experience no symptoms for a week or more, if at all, the disease spreads below the radar, exponentially and apparently at random . If Daegu's wife had stayed home that Sunday in February, the outbreak in South Korea could have been less than half of what it is.
Some countries that should have been flooded with cases are not, leaving researchers stumped.
Thailand reported the first confirmed case of coronavirus outside China in mid-January, from a traveler from Wuhan, the Chinese city where the pandemic is believed to have started. In those critical weeks, Thailand continued to host an influx of Chinese visitors. For whatever reason, these tourists did not trigger an exponential local transmission.
And when countries do everything wrong and still end up seemingly not as battered by the virus as one would expect, guess why.
"In Indonesia, we have a health minister who believes that you can pray to keep Covid away, and we have very little evidence," said Dr. Pandu Riono, an infectious disease specialist at the University of Indonesia. "But we are lucky to have so many islands in our country that limit travel and perhaps infections."
"There is nothing else we are doing well," he added.
c.2020 The New York Times Company