Thousands of people in Cuba may have had early, undiagnosed cases of coronavirus

Tribune Content Agency

MIAMI — Four days after the World Health Organization declared the coronavirus outbreak a global pandemic on March 11, a Cuban government official assured tourists that the Caribbean island was a “safe destination.”

The country continued promoting tourism until a sudden change in position on March 20, when, in a night television show, Cuban leader Miguel Díaz-Canel said he was ordering travel restrictions.

At the time, Cuban health authorities said there were only 25 confirmed cases of coronavirus infections. But a troubling report by Cuba’s renowned epidemiology center shows the country was experiencing a stunning spike in new cases of “acute respiratory diseases” that experts believe includes people with COVID-19 who were not counted as such.

According to data reviewed by the Miami Herald, in the week ending on March 21 there were 144,095 newly reported “acute respiratory illnesses.” By March 28, the number of new weekly cases of people with acute respiratory diseases rose to 188,816, more than double the weekly average this year.

“Not only could the increase be explained by a COVID-19 outbreak, it most likely does reflect the COVID-19 outbreak based on when it started and what has been going on in the world,” said Dr. Aileen Marty, an expert on infectious tropical diseases and director of the Florida International University Health Travel Medicine Program.

“It is very probable that many people in Cuba had the virus in March and were counted simply as Acute Respiratory Illness,” she added.

The statistics were published by the island’s Pedro Kourí Institute of Tropical Medicine in its weekly bulletins. The data come from a mandatory reporting system by the Cuban Ministry of Public Health in place since at least the early 2000s to monitor acute respiratory diseases, a category that includes pneumonia, influenza, the common cold and previously known coronaviruses that may produce symptoms similar to COVID-19, the illness caused by the novel coronavirus.

In total, the institute, known as IPK and a key player in the country’s coronavirus response, reported 491,494 cases of acute respiratory diseases between March 15 and April 4.

Dr. Carlos Espinal, an epidemiologist and expert in tropical diseases who heads the Global Health Consortium at FIU, also believes the data probably include unreported cases of people with COVID-19.

“At present, countries only report confirmed cases and confirmed deaths at the hospital sites. We know by now that the numbers are higher in both indicators,” he told the Herald. “What you see in Cuba probably corresponds to this key issue of under-reporting cases and deaths.”

An uncommon pattern and the highest number in five years

Until March 14, it seemed like a typical year for respiratory diseases in Cuba, with fewer weekly cases than in 2019.

Then suddenly, in the week ending on March 21, there was an avalanche of people seeking treatment for respiratory illnesses, as many as 144,095, a 47% jump in cases from the previous week.

That figure is also 50% higher than the one reported in the same week in 2019.

What happened next is unclear, because the IPK has not published a bulletin with the data corresponding to the week between March 22 and 28. However, according to the accumulated total figures reported for 2020, there were another 188,816 cases during that missing week.

That unpublished figure is the highest number reported since 2015, according to a Herald analysis of bulletin data comprising five years. The next highest number, 167,570, was published in the week ending on Sept. 24, 2015.

When the IPK resumed publishing data for the week ending on April 4, there were another 158,583 cases — 70,698 more than during the same week in 2019, an 80% increase.

The IPK publishes figures with a delay of from about one to three weeks.

An analysis of the data since 2015 found that weekly numbers can swing in the thousands, but do not usually rise so fast and so high. Even in years with many reported illnesses, like 2015 and 2016, the numbers rose incrementally.

There are a few examples in the statistics reviewed when cases grew sharply from one weekly bulletin to the next, but those involved reports that included fewer days in the week or holidays.

Last Thursday, the IPK reported a 33% drop in new cases during the week ending on April 11, to 106,647.

In the bulletins, the institute did not explain the increase in acute respiratory illnesses nor link it to the circulation of the new virus. But the emerging data might have led the Cuban government to impose travel restrictions effectively shutting down tourism.

By March 21 — the date of the first bulletin showing the jump in numbers — there were only 35 confirmed cases of coronavirus infections officially reported, and the government said there was no community transmission.

If there is medical evidence to support that claim, it has not been made public. At the time, testing was severely limited. As of March 22, Cuban labs had only conducted 518 tests despite having 954 suspected cases in hospitals and more than 30,000 people being monitored for COVID-19-like symptoms at home.

Marty, who is co-editor of One Health, the Official Journal of the International Federation for Tropical Medicine, dismissed other potential explanations — like a statistical error, a bad flu season, or climate conditions — to account for the increase in acute respiratory illnesses in late March and early April.

“The idea of seasonal infection associates a specific infection with a distinct season of the year,” she said. “This was accurate to some extent when humans lived and worked outdoors with minimal protection from even the most severe climate conditions. Today, in most countries on earth, including Cuba, the overwhelming majority of person-to-person transmission events happen indoors.”

Data reported by Cuba to the Pan American Health Organization also suggest that influenza was not the main reason for the soaring numbers.

In its weekly influenza situation report, based on data provided by health ministers in the Americas, PAHO said that as of March 20, “influenza activity remained elevated” in Cuba. But Paho added that “percent influenza positivity decreased to moderate levels of intensity when compared to the average% positivity observed during 2010-2019 seasons.”

Cuba stopped reporting new data to PAHO the following week.

“Flu in our Caribbean and tropical countries circulates all year round with peaks on April-May, September-October,” Espinal said. “What you see (in the IPK data) includes probably cases of Covid-19 in addition to other respiratory viruses.”

There is still another potential explanation that could partly account for the rise in reported cases of acute respiratory diseases.

Back in February, the government ordered primary doctors to monitor people who had traveled, and established medical control points at airports. On March 17, health authorities ordered thousands of medical students to knock on homes and look for people experiencing any symptoms like those of COVID-19.

The increased surveillance might have uncovered more cases than usual, and that could have skewed the data if the Ministry of Public Health included those numbers in its regular monitoring system.

But that reporting system usually includes only people diagnosed in medical facilities, not just surveyed for symptoms. The reports are not supposed to include mild cases, the kind that people usually treat themselves at home.

Even if more cases of acute illnesses were discovered and reported, that still leaves unanswered why several thousands of Cubans were sick at the time a new virus was spreading rapidly worldwide.

The IPK did not reply to an email request for comment. Two phone numbers that appear on the institute’s website were disconnected. Calls to another number listed in the official Cuban phone guide went unanswered.

Presented with the data analyzed by the Herald, Ashley Baldwin, a PAHO spokesperson, said the increase in respiratory diseases starting in mid-March was led by “the active investigation of people with respiratory symptoms, which is carried out by primary health care services in search of cases of COVID-19.”

“However, COVID-19 has been ruled out in most of these cases,” Baldwin said.

PAHO did not explain how Cuba was able to rule out the coronavirus, especially at a time when testing was minimal. The spokesperson did not clarify if the organization, which relies on government self-reported data, made an independent verification.

The spokesperson also suggested the increase in acute respiratory cases was linked to influenza despite the organization’s report stating the circulation of flu was “elevated” but moderate when compared to last year.

“During this time of year, the increase in acute respiratory cases is common in the country as it is the season with the greatest circulation of influenza,” she said.

After its initial denial that the virus could get out of control on the island, Cuban authorities have enforced quarantines and imposed hefty fines and even jail sentences on those not complying with social distancing and other measures to contain the outbreak.

On Monday, the Ministry of Public Health said 1,668 people had tested positive for COVID-19, and 69 had died.

The ministry’s numbers have raised eyebrows among dissidents and experts. They doubt the reported 3% positive rate in the coronavirus tests conducted so far, more typical of countries such as New Zealand with very different population density and economic conditions.

The island is facing a devastating economic crisis, with shortages of soap and significant disruptions in water services. And many Cubans spend most days in lines to buy food, defying any hopes of social isolation.

“Preventive measures were taken late, and many have not been implemented fully, mostly because the government does not have enough resources. There is not even enough soap,” Cuban demographer Sergio Díaz-Brisquet said. “Cuba has other health indicators such as an aged population and higher percentages of people with pre-existing conditions that would suggest they have a more serious problem.

“And they have misrepresented health data in the past, for example, regarding dengue epidemics,” he added.

The Cuban government has increased its diagnostic testing capacity thanks to donations by the World Health Organization and China. But it has not said much about antibody testing, which could help to understand how widespread the virus is in a community.

Experts around the world have warned about the probable undercount of cases of coronavirus and related deaths. The Financial Times studied mortality statistics across 14 countries and estimated that the global coronavirus death toll could be 60% higher than reported.

In Cuba, “there is no independent entity that can report its own (coronavirus) figures or criticize the government’s data,” Cuban-American economist Carmelo Mesa-Lago said in a Harvard webinar in which he gave a grim assessment about the impact of the pandemic on the island’s economy.

As has happened in the U.S. and many other countries, where the coronavirus started circulating earlier than first thought, those March reports suggest that many more Cubans could have had the virus. Without widespread antibody testing, it might never be known.

“All the available evidence,” Marty said, “reflects a large outbreak of COVID-19 in Cuba that became evident on the week ending March 21.”


©2020 Miami Herald

Visit Miami Herald at

Distributed by Tribune Content Agency, LLC.