Saturday, May 3, 2014

Stay Away from Camel Milk and Egyptian Tomb Bats

A deadly SARS-like virus is sweeping the Middle East -- could it go global?  



BY Laurie Garrett

Anxiety runs deep in Saudi Arabia these days. A SARS-like disease that kills a third of those it infects is suddenly, and mysteriously, surging inside the kingdom. The country is struggling for answers -- and so are its neighbors.

It's called the Middle East respiratory syndrome (MERS), and though the majority of the cases have been found in Saudi Arabia, 14 other countries have reported instances. Make that 15: Egypt just reported a case at the end of April.

The virus first emerged in the eastern oasis town of Al-Ahsa in the spring of 2012. But not until April 2014 did it seem likely to be a pandemic: That is to say, nearly half of all cumulative cases since 2012 have occurred in Saudi Arabia in April 2014. As of April 29, the kingdom reported a total of 345 cases since the virus first emerged -- 105, or 30 percent, of them have proved fatal. Seventy-three cases have been reported outside Saudi Arabia, and nearly all those cases have been linked to travel to the kingdom.

Among those cases, at least two were among religious pilgrims: The first pilgrim, from Malaysia, reportedly drank camel's milk in Jeddah before returning home, and the second pilgrim, from Turkey, died last week in Mecca. But a considerable number of cases -- nine out of the 14 reported in April -- have included foreign workers, such as nurses, domestic workers, and oil industry employees. Most of these workers have stayed in Saudi Arabia for their treatment, though the Philippines issued a health alert after an infected nurse returned to Manila.

And this sudden surge -- both inside and outside Saudi Arabia's borders -- has put pressure on the Saudi government. Health Minister Abdullah al-Rabeeah was fired on April 21, replaced by Labor Minister Adel Fakeih, who now leads two ministries. In keeping with his labor portfolio, Fakeih immediately expressed special concern about the disproportionate toll the SARS-like virus is taking among health-care workers, ordering transfer of all the kingdom's MERS cases to King Saud Hospital in north Jeddah, where they will be treated under severe infection-control conditions. Between March 20 and April 26, some 29 percent of Saudi MERS cases and deaths were among health-care workers. Even King Abdullah changed his summer plans to visit hospitalized patients in a Jeddah hospital.

Source: European Centre for Disease Prevention and Control, Rapid Risk Assessment, April 24, 2014*

The Saudi Health Ministry has lost a great deal of credibility, as rumors have spread of incompetence, coverups, and lost records.
The Saudi Health Ministry has lost a great deal of credibility, as rumors have spread of incompetence, coverups, and lost records. (And much of the information has moved through social media. I've even received tweets from people all over the world claiming that Saudi health officials have documented MERS cases as "heart attacks" and that nurses fear for their safety amid stock-outs of protective gear.) Local physicians began reporting a surge in Jeddah and Riyadh as early as April 1, but then-Health Minister Rabeeah issued this unequivocal statement: "Jeddah: the novel coronavirus situation is reassuring and thankfully does not represent an epidemic." The daily tolls of cases and deaths have been increasingly confusing, as outside health agencies and reporters struggle to make sense of updates from Riyadh. Recently the Washington Post's editorial board cried out for accurate, transparent information from the kingdom.

 
Source: European Centre for Disease Prevention and Control, Rapid Risk Assessment, April 24, 2014
The elevated concern in the kingdom reflects a significant jump in the number of cases between April 15 and 21, when 49 new MERS patients were hospitalized, mostly in the city of Jeddah. The World Health Organization (WHO) issued a statement of "concern" noting:

"Approximately 75% of the recently reported cases are secondary cases, meaning that they are considered to have acquired the infection from another case through human-to-human transmission," WHO Regional Director for the Eastern Mediterranean Dr Ala Alwan said. "The majority of these secondary cases have been infected within the healthcare setting and are mainly healthcare workers, although several patients are also considered to have been infected with MERS-CoV while in hospital for other reasons."

According to the WHO, cases have now been found in Jordan, Kuwait, Oman, Qatar, the United Arab Emirates, France, Germany, Greece, Italy, the United Kingdom, Tunisia, Malaysia, Yemen, and the Philippines. Egypt also reported its first case in April.

Source: European Centre for Disease Prevention and Control, Rapid Risk Assessment, April 24, 2014

The political stakes are high for King Abdullah and the Saudi royal family as they are the keepers of the most sacred sites of Islam: Mecca, Medina, and Jeddah. Every year, starting in late spring and extending roughly to October, millions of Muslim pilgrims descend upon the sacred cities for the religious observances of umrah and the hajj. It is the duty of the king and his royal family to provide safe and healthy passage to all pilgrims. In addition, Saudi Arabia is absolutely dependent on foreign workers to sustain everything from basic construction and household labor to the advanced engineering of the kingdom's petrochemical industry and oil fields. According to the International Labor Organization, in 2006 the kingdom had a total workforce of about 7.5 million, 54 percent of whom were foreign. In 2013, however, the Saudi government expelled thousands of foreign workers, so these numbers may not reflect current trends. 

Worry in the Philippines since the return of an infected national has grown high enough that the government has issued "do not panic" bulletins in Manila. Nevertheless, fewer Filipinos are reportedly applying for Saudi jobs. And on April 14, after five Filipino nurses were quarantined in the United Arab Emirates following their exposure to a MERS patient, the Philippines' Department of Foreign Affairs urged Filipinos in the Middle East to "take precautions."

The sharp rise in cases has scientists and Saudi authorities asking a raft of the usual outbreak questions:
Has the virus changed, adapting genetically to the human species in a way that makes it more infectious?
Has the virus changed, adapting genetically to the human species in a way that makes it more infectious? Is this surge due to laboratory artifacts or some changes in testing practices in Saudi Arabia?

 
Verification tests in Europe of the Saudi diagnoses rule out laboratory error or changes in diagnostic methods as explanations for the surge. On April 26 a German team completed genetic analysis of strains from three patients diagnosed in the new surge, comparing those genomes to earlier MERS strains. No significant differences were found -- certainly none that could lay responsibility for the surge on viral mutation. Nevertheless, many news organizations and individual scientists have speculated, without evidence, that the spike in cases signals viral adaptation to the human species.
The WHO has offered to mobilize an international team of scientists to assist the Saudis in doing the detective work to determine why this surge is unfolding and what can be done about it. To date the Saudi government has frustrated many outside scientists who have tried to help on the ground or offer epidemiological insights from afar. But the sorts of data the scientists say they need -- such as the occupations of infected individuals, travel details prior to infection, details regarding possible exposure to camels or other animals -- the Saudi government has not provided for most cases. Even leading Saudi news organizations have called for greater transparency from government officials. "What has been shocking and extremely disturbing are the countless stories and rumors that have spread just as quickly and just as aggressively as the virus itself," an author wrote in the Saudi Gazette.

***
So why is the surge happening now? MERS is a coronavirus, part of a family of microbes that includes SARS (severe acute respiratory syndrome). Clues to the largely mysterious natural history of MERS, how it spreads, and where it comes from may well lay with the SARS saga. The SARS virus is a fruit-bat microbe that causes no harm to the flying animals. The 2002 and 2003 human epidemic was preceded in the late fall of 2002 by an outbreak in captive civets, sold for exotic meals in live-animal markets throughout China's southern Guangdong province. It is not certain how the civets originally acquired SARS, but animal hunters and smugglers commonly caged their prey beside one another, possibly putting bats and civets side by side. In February 2003, when I reached the animal market in Guangdong's megacity, Guangzhou, where the epidemic was spawned, I found thousands of caged, miserable animals stacked atop one another, defecating and urinating upon each other. Moreover, animal dealers -- who would blithely grab animals at customers' requests -- handled the civets, possibly cross-contaminating cage after cage. I tracked down the first cluster of SARS cases, centered on a restaurant famed for its civet meals. The people became infected through the handling, slaughter, and cooking of the animals. In the earliest stages of the epidemic in 2002, all human cases were linked to civets or to individuals who handled civets. Once the primary cases entered the hospitals, however, infection spread like wildfire from person to person across the wards and through the health-care worker populations.

In the case of MERS, there is now plentiful evidence that its primary host is another fruit-bat species, the Egyptian tomb bat. Nobody knows why the bat virus only emerged into people in 2012. But it seems that it originated in the Al-Ahsa date-growing oasis town in eastern Saudi Arabia, where the bats nest atop the palm trees. In April 2014, an international research team published evidence that bats may be able to carry dangerous viruses like Ebola, SARS, and MERS without harm to themselves because the physical action of flight elevates their metabolism and innate immunity. More sedentary animals -- camels and humans, for example -- lack the same elevated metabolic impact on their immune systems.

In some manner the bat virus spread to camels, which can be considered the MERS equivalent of civets in the viral chain of transmission. And some of the human MERS cases have been linked to camels. For example, the Malaysian pilgrim who succumbed to MERS visited a camel farm and drank camel milk before taking ill. During the last week of March, an animal trader from Abu Dhabi came down with MERS after visiting a camel farm. A Saudi man who contracted MERS was infected with a strain that proved a 100 percent genetic match to the virus extracted from one of his personal camels. And laboratory analysis of camels' milk samples has found many contaminated with the virus, which appears to be harmless or cause only mild illness in the animals. This week the new Saudi minister of health urged residents of the kingdom to shun camel milk consumption.

Very recently scientists discovered that camels from as far away as Tunisia, Nigeria, Ethiopia, and Sudan test positive for MERS infection. The geographic area encompassed by these MERS-infected camels perfectly overlaps the North African terrain of Egyptian tomb bats. It would seem that the bat and camel connection for MERS is an ancient one that may have led to the occasional human case -- even death -- over the centuries, occurring sporadically but undetected.

Finally, on the camel front, it must be noted that only a small minority of MERS patients have had histories of contact with the animals or consumption of their milk. While the camel connection may explain sporadic cases, the vast majority of MERS cases seem to have been acquired by other means.

***
Al-Ahsa, where MERS emerged, is surrounded by desert. Where there is spring water, orderly and well-tended palm orchards stand, without competition from other vegetation. Date farming is an enormous business for Saudi Arabia, with farmworkers shooing away bats to tend to the trees at key points in the growing season. In April, date farmworkers scale the trees, reaching the very tops to carry out pollination work, a labor-intensive activity that entails removing the male components of the plant, shaving out the pollen, sprinkling pollen on the female portions of the tree, and tying and clipping the now-fertilized sections in a manner that increases fruit yield. If MERS-infected Egyptian tomb bats or their leavings are present, the workers will likely be exposed. Late March and the month of April comprise a time of especially intense work in the date palms and potential exposure to the bats and their leavings.

Remarkably little is known about the behavior of these bats, though it seems April and May is breeding season for the animals and June is birthing time, when a single progeny per female bat is born, and fiercely defended.

Farmworkers will return to the treetops in June, as the fruits are getting larger, to fend off bats and other pests and to wrap the fruit clusters in protective mesh. And their third potential period of exposure to bats will come in late summer and early fall, for the harvest.

There was no surge in MERS cases in 2013 at this time, but that may reflect labor issues in the kingdom. Early in 2013, Saudi Arabia enacted a tough new labor law and tossed thousands of workers out of the country. Hardest hit was the agricultural sector, which relied heavily on foreign migrant labor. The labor crunch for the date industry was so acute that the entire harvest of 2013 was threatened and last fall a 30-day amnesty was decreed specifically for date workers. The action came too late for the full range of activities necessary for an ideal yield, including the April pollination work, and date prices soared. This year date growers lobbied hard for early labor exemptions, hoping to bring in a large harvest.

If this cycle is, indeed, at the root of this year's seasonal surge in MERS, it mirrors what has been seen with another bat disease, Nipah, in Bangladesh. I visited a Bangladeshi village that had been hard hit by the disease in 2010. Grieving parents whose children died of Nipah showed me where the bats nested high in the palm-oil trees, sucking sweet oil from the catch devices farmers hung -- something like maple tree taps. During the day the family's children climbed up to drink the sweet oil, becoming infected by contacting parts of the tree the bats had defecated and urinated on.

***
By all accounts, King Fahd Hospital in Jeddah was the scene of chaos and hysteria on April 1.
By all accounts, King Fahd Hospital in Jeddah was the scene of chaos and hysteria on April 1. That day, six ailing nurses and a physician were diagnosed with MERS, sparking an outcry from the entire hospital staff. One of the nurses came down with the disease just days after his wedding, leading authorities to insist the source of the cluster of cases was not the hospital, but the feast. The accusation only fanned the fire, and some physicians quit their jobs, decrying unsafe working conditions for those treating MERS patients.

 
Clusters like this of transmission are surfacing inside hospitals in Saudi Arabia, with some 75 percent of cases in the April surge being human-to-human transmission, about a third of them health-care employees. Nearly all public information about hospital spread has come from the Ministry of Health hospitals -- public facilities that service foreign workers, migrant laborers, and average Saudis. But ministry facilities account for less than half of the MERS cases. On April 15, for example, the Health Ministry released this breakdown for then-hospitalized MERS cases:

Ministry of Health hospitals: 72
Department of Defense hospitals: 39
National Guard hospitals: 30
Security forces hospitals: 4
Saudi Aramco hospitals: 14
Private hospitals: 20
University hospitals: 5
King Faisal specialist hospitals in Riyadh and Jeddah: 10
Total: 194

Combined, the military, security forces, and royal family facilities accounted for 83 cases, about which little is known. If MERS is spreading within the security and military ranks, Saudi national security would be an issue, but almost nothing is known about these cases.

On April 15, the National Scientific Committee for Infectious Diseases issued its verdict on the Kang Fahd outbreak and escalation of cases in Jeddah: "The clustering of cases found in the city is actually in line with the nature of the disease, which tends to affect an aggregate of cases, and the infection pattern of the virus does not differ from that in the rest of the kingdom. The members also added that the preparedness of hospitals and health-care facilities follows national and international infection control standards and does not need any additional preparation, as all necessary machines and supplies required to treat cases are available."

The patent fallacy of the committee's statement would be revealed in a few days, as MERS case numbers soared.

Some Saudi experts have insisted that proper face masks, alone, reduce transmission risk by 80 percent. The SARS experience would argue against such assurance, as many masked doctors and nurses were infected. The virus spreads via hands, surfaces, stethoscopes, used latex gloves, even contaminated contact lenses. Hospitals in Hong Kong and Singapore stopped the spread of SARS by compelling all staff to work in teams, donning and removing their protective gear under the watchful eyes of co-workers to be sure each step was executed perfectly. On a less sophisticated level, the SARS outbreak in Hanoi was stopped when all patients were removed from the higher-tech French Hospital and placed in the aging, warfare-damaged Bach Mai General Hospital. French Hospital had air-conditioning and high-tech instruments, while Bach Mai's windows were open, overhead fans moved the muggy tropical air around, and the most acute cases were tended to by SARS survivors.

The guidelines for SARS infection control in clinical settings are well known, detailed, and internationally recognized. Among the WHO recommendations is: "Turning off air conditioning and opening windows for good ventilation is recommended if an independent air supply is unfeasible," a tough requirement in the Saharan desert heat. Half of the roughly 8,500 SARS victims in 2002 and 2003 were health-care workers, but the rates of hospital infection varied widely, depending on the physical conditions of the facility (French Hospital versus Bach Mai in Hanoi) and the institutions' long-standing infection-control standards.

***

The question now is: Will the virus go global? MERS is at least three times more lethal than SARS. About 31 percent of MERS patients have eventually succumbed versus 8 percent of SARS cases.

SARS spread to 31 countries, causing serious epidemics and spectacular economic stress in half of them, especially China, Singapore, Hong Kong, Canada, and Vietnam. In Canada, where 40 percent of the 375 SARS cases were hospital personnel, the globalization of SARS was especially sobering: One of the wealthiest, most advanced nations on Earth struggled mightily to stop the virus's spread. The also technically advanced Chinese University hospital in Hong Kong was ripped apart by grief, with three of its staff sickened by the disease in the first two months of the region's epidemic.

The specter of a SARS-like, 31-nation, 8,500-patient MERS pandemic is three times more horrible, due to the greater virulence of the virus.

Without knowing the relative roles date palm farming, Egyptian tomb bats, camels, hospitals, and other possible factors play in the spread of MERS in Saudi Arabia, it is extremely difficult to predict the pandemic potential of this disease. Clearly, spread inside hospitals is transpiring and must be stopped before the world can possibly breathe a sigh of relief. This will require a great deal more than face masks and the scanty patient information released to date by Saudi authorities.

But the vast majority of MERS cases remain mysteries: How did patients get infected? What were their professions, living conditions, recent travels, and family situations? Have there been clusters of transmission outside clinical settings, such as within households, workplaces, military barracks, or schools? Saudi health authorities simply must find and release far more detail on the known patients and their contacts.
Parallels with the ongoing Ebola epidemic in Guinea and Liberia abound. In both cases the virus spreads easily inside health-care settings, putting other patients and doctors and nurses in peril. Both viruses can be protected against, however, with fairly basic infection-control procedures and quarantine. Ailing patients with both viruses are limited to palliative care, as no magic-bullet drugs or vaccines exist for either virus. And in both Ebola and MERS scenarios, a poorly understood cycle of transmission from bats to intermediary animals and then to humans is responsible for introducing the virus -- perhaps repeatedly -- to our species. Mysteries abound.
But one crucial difference between MERS and Ebola must be underscored: the respective settings of the outbreaks. Today, Ebola is unfolding in one of the poorest, remotest, most difficult locations on Earth, one rarely visited by tourists, traders, or travelers. It is highly unlikely that an infected Ebola victim will have the capacity to board a jet headed to nearby Nigeria, much less London, Paris, Beijing, or Los Angeles.

But MERS is unfolding in one of the wealthiest countries on the planet, in an unusual kingdom built on black gold, dependent on the labors of tens of thousands of foreigners, and host to one of the modern world's most holy set of shrines, visited by more than a million people annually from nearly every country on Earth. And it is a kingdom nestled in the midst of the world's most difficult, war-torn region, where hundreds of thousands of refugees live in danger and squalor, riots and civil tension periodically erupt, mass migrations of populations are routine, and governance cooperation between nations is nearly absent, for everything, even public health.

*Correction, May 2, 2014: The two charts and one map used in this article are from the European Centre for Disease Prevention and Control's Rapid Risk Assessment of April 24, 2014. The original version of this article did not include the source. (Return to reading.)

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