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How Global Outbreaks Are Contained

Disease outbreaks can quickly become pandemics in a globalised world. But we have already shown how they can be contained, and beaten.

On 31 January 2003, a fishmonger called Zhou Zuofen was admitted into the Sun Yat-sen Memorial Hospital in the Chinese megacity of Guangzhou. He was ill with a peculiar form of pneumonia which had already cropped up in a small number of patients since the previous November.

This disease is now thought to have first infected a farmer in China’s Foshan county, part of the Guangdong province which borders Hong Kong. It caused flu-like symptoms which included muscle pains, fever, cough, extreme tiredness and a sore throat. The disease then sometimes caused pneumonia, sometimes a secondary form from separate bacterial infection.

Zhou’s infection catapulted this obscure disease from a regional curiosity to a cause of international panic. While at Sun Yat-sen Memorial Hospital, he is now thought to have passed on the infection to 30 health workers. One of the hospital’s doctors, Liu Jianlun, ended up treating nine patients infected with the disease. From around 15 February 2003, he started showing symptoms of mild illness, but did not connect it to the disease he had been treating. He left the city to attend a family wedding party in nearby Hong Kong. And with that, the mystery ailment was on its first step toward becoming an international emergency.

On 21 February, the doctor and his wife checked into their room on the ninth floor of Hong’s Metropole Hotel. It was to be a short stay. By the following morning, the doctor knew he was ill enough to need medical attention. He walked the short distance to Kwong Wah Hospital. Knowing he was seriously ill, the 64-year-old doctor requested to be placed in isolation. His foresight had far-reaching consequences. Had he not made this request, things could have been much worse.

The disease Liu had been carrying would go on to be known around the world as Sars (severe acute respiratory syndrome). The doctor’s hunch is widely thought to have prevented this new threat from becoming a fully fledged global pandemic. The doctor, however, did not live to see it contained. He died on 5 March, after two weeks fighting the infection in isolation.

Though isolated cases would be reported as late as March 2004, the World Health Organization (WHO) declared the emergency over on 5 July 2003, having seen no new cases for 20 days. In the end, Sars would infect more than 8,000 people in 29 countries, killing at least 774 of them – a fatality rate of just under 10%, far higher than serious seasonal ailments such as flu. Its effect would be most keenly felt in China, Taiwan and Canada.

International air travel very quickly delivered Sars to countries thousands of miles from the initial outbreak

Just like the current Covid-19 pandemic the world is currently fighting, Sars was delivered via airplane. While the Spanish Flu emerged over a century ago, and crawled its way across the globe on passenger steamers and trains that took weeks and months, this infection could arrive on the other side of the world in little more than a day. The potential for disease outbreaks to become pandemics has grown as exponentially as our ability to travel has made the world shrink.

Viral infections may be as old as living cells themselves. They have kept pace with human development; occasionally jumping from other species to humans when the conditions are just right. As our populations have increased, and settlements have encroached more and more on the forests their natural hosts inhabit, the threat has risen. Sars, and the frightening haemorrhagic fever Ebola, are 21st Century diseases in a crowded world.

Sars began in China, but one of its most serious outbreaks was half a world away in the Canadian city of Toronto, in the province of Ontario. Jacalyn Duffin, a Canadian medical historian and haematologist, was working near Toronto when the outbreak first happened. “Being a historian who is also interested in disease, I was paying attention from the get go,” she says.

Sars arrived in Canada with an elderly Toronto resident, Kwan Sui-Chu, who had been visiting Hong Kong; she had been staying at the Metropole Hotel. She fell ill and died at home, but not before she fatally infected her son, who passed the disease on to a cluster of other people before he died at the Scarborough Grace Hospital.

Ontario’s health services were soon on a war footing. “Every hospital in Ontario had to implement strict quarantine,” says Duffin. “To get into work you had to line up outside and get your temperature taken.”

Sars was so communicable that it was vital for those who were ill to be properly tracked. Duffin says hospital workers were given new photo IDs that included a barcode, so that they could be tracked when they moved from one zone to another. “It was amazing to me how quickly that came into being,” she says.

Tracking patients is one of the three most important weapons that health agencies have when it comes to dealing with pandemics. The trinity is tracking, isolation, treatment. We have already seen some Asian countries, such as Singapore and South Korea, seemingly flatten the curve of coronavirus transmission by rigorous tracking of the infected. These are lessons learned during the Sars outbreak.

Sars showed that pandemics would cause great disruption to normal life

In the end, Sars infected some 400 people in Canada, and killed 44. Had the Canadian health authorities not dealt swiftly with the outbreak, it may have killed many more.

Isolation has another, more medical, term – quarantine. The word comes from the medieval Venetian word “quarantena”, referring to the 40 days Christ spent in the wilderness according to the Bible. Long before science confirmed that viruses and bacteria cause disease, quarantining was a very effective weapon in the fight against plagues.

“In Milan, during the great plague, they closed the gates,” Duffin says. “If there was plague in a house they blocked you in and they wouldn’t allow you out until you recovered – or died. And because of that, Milan had a much lower incidence of deaths than the rest of Italy.

“I got a phone call in the middle of the epidemic because the mayor of Toronto at the time was upset because they were naming Toronto in a travel advisory, and recommending people didn’t go there.

“Here I was, a historian just sitting in her office minding her own business. And Ian Gemmill [Canada’s Medical Officer of Health at the time] asked me , ‘Has quarantining ever worked?’ He asked me that question. I said, ‘It works.’ He then asked me, ‘I need to know how many lives it’s saved.’ And I said, ‘They don’t count the people who never get sick.’”

There was one aspect of Sars which helped humanity fight it – Sars was a novel virus to the human immune system. When the human body encountered it, the immune system went into overdrive to fight it because it didn’t yet have antibodies. This meant that those who were infected by it very quickly became ill as a result of this over-reactive response, also known as a cytokine storm. This limited the number of people who could be infected by people with the disease. Duffin says: “You had the signs of Sars, and you either died or you very quickly got better.

“It’s strange how long these people [the Covid-19 patients] who have gone into intensive care stay there.” Covid-19 has a relatively long incubation period – several days and up to two weeks in some cases – and it can take weeks before even seriously ill patients recover or succumb to the virus.

There was another far-reaching effect of the Sars virus, at least in Canada. “Up until then, Canada didn’t have a national public health agency,” says Duffin. While there had been pandemic planning before, it had been at a provincial level. “Sars was almost like a dummy run.”

Duffin was bought into pandemic planning once Canada’s new federal public health agency was formed in 2004. Pandemic planning was regularly practised in the years immediately after the Sars outbreak. In recent years, however, the planning had become more sporadic due to budget cuts and the memory of the 2003 crisis fading.

“Sars was a long time ago,” Duffin says. “The younger people [at the agency] didn’t know about it so much. Though the structures are still in place, they’re not as robust as they were before.”

Yet, Sars did lead to a lot of the pandemic procedures we have seen swinging into action in the last four months being put in place. But it is far from the only serious disease outbreak to have taken place recently.

Had Canadian health authorities not swiftly dealt with the pandemic, it could have been much worse

In 2009, the Swine Flu Pandemic is thought to have killed more than 250,000 people as it swept around the world, infecting up to 1.4bn people – more than were infected by the Spanish Flu. In 2016 WHO declared an emergency over the Zika fever as it spread across South and Central America, Asia and the tropical Pacific. While the virus produced only a mild fever in adults, it could cause severe birth defects if pregnant women contracted it.

But by far the most serious outbreak, at least in terms of the damage it could have caused in the developing world, was the 2013/14 outbreak of Ebola in West Africa.

Ebola is a gruesome pathogen. A haemorrhagic fever, it can cause severe internal bleeding – in the worst cases, people bleed from their eyes, nose and other orifices as their organs shut down. The first identifiable cases amongst humans were reported in 1976, during an outbreak in Zaire (now the Democratic Republic of Congo, or DRC). The outbreak took place in the village of Yambuku, in the north of the country, near the Ebola River, from where this new disease took its name.

Presumed to have jumped from the wild to humans via the bushmeat trade, Ebola is thought to be carried by bats. The Zairean government quarantined the region amid rising panic and the outbreak was relatively quickly contained, but the fatality rate was shockingly high. Of the 318 people confirmed to have been infected, 280 died. That is a fatality rate of 88%.

Over the next few decades, sporadic outbreaks occurred mostly in southern Africa, mostly in the DRC and neighbouring Uganda. Each time hundreds of cases were reported. The worst fatality rate, during an outbreak in the DRC in 2003, was 90%.

The worst outbreak so far, however, came in 2013 and 2014. Instead of the vast jungle-covered interiors of the DRC, this took place in the far more crowded countries of West Africa. The outbreak was traced to a one-year-old child who developed the infection and died in Guinea. From Guinea, it spread to Liberia and Sierra Leone, becoming global news as it did so.

Gwendolen Eamer worked for the International Federation of the Red Cross both in Guinea and Sierra Leone during the outbreak, which ended up killing more than 11,000 people. But the information gleaned from those sporadic outbreaks was vital. “A lot was learned about how you treat people, that it was crucial there was the availability of supportive care, there was hydration to stop them losing fluids.”

The Ebola outbreak in West Africa showed health agencies had to be sensitive to local burial practices

Eamer says the supportive care and the vaccines developed since to protect against Ebola have helped blunt its effects “but they are not a silver bullet”.

She says groups likes the Red Cross had to learn a new way of working. “The way we had dealt with these communities had been very top down,” she says. “It was a case of ‘we have the expertise you need’.”

Eamer says the clinical and medical insight was often not reassuring the people affected by the outbreak. “For most people that kind of information doesn’t mean anything. It’s more, ‘what do I have to do to change my behaviour? How do I help myself and my children?’.

“You need to be connecting from within the community.”

Eamer says the Ebola outbreak showed the importance of the holy trinity of pandemic prevention – detection, isolation and treatment. Most crucial of all, in the densely populated settlements in West Africa, was extensive contact tracing.

“It did very well in tackling Ebola,” she says. “We did double ring tracing, which is everyone you came in contact with and everyone they came in contact with.” This technique doesn’t necessarily require expensive technology, but it does require many, many hours of interviewing and follow up. “It’s ‘operationally heavy’ but it does work,” adds Eamer.

Western clinical medicine also sometimes butted heads with local custom, and Eamer says the agencies had to learn how to be flexible around these. One such case has been burial of Ebola victims. Given that bodies could still possibly transmit the disease, they had to be completely zipped up in body bags to avoid contamination. But local custom calls for the face to be visible at burial, otherwise the soul will not be able to leave the body. In some places, it was also custom for grieving family members to touch the face of their dead relative.  “If your child has died, that ability for your child’s soul to get into Heaven is really important for you as a parent,” says Eamer.

West Africa is built up and with a mobile population, which made the outbreak much more challenging to deal with

After talking with local leaders, they found a solution – a hole in the body bags around the face , in keeping with the traditional practices. “It wasn’t perfect but it was good enough,” says Eamer. “It’s about listening, we’re told what really doesn’t work for them and how we can adapt around that.”

Good support from local communities has effects long after the outbreak dies down. Health agencies have found local infrastructure – traditional healers, community leaders, farmers and health workers – are an incredibly powerful tool in making sure local outbreaks don’t become epidemics.

“Communities know what’s normal for them,” she says. One risk factor that often forewarns possible outbreaks of diseases like anthrax is mass animal die-offs. “If you’re from a Masai community, you know it’s not normal for five cows to die in 24 hours.”

That community early warning system really works: it caught the first case of Covid-19 in Somaliland a few weeks ago.

Alexander Kumar, a global health medical doctor based at King’s College in London, also saw the Ebola outbreak at close hand. He worked at a treatment clinic in Sierra Leone during the outbreak, and saw patients die in front of him.

“An expert in Ebola 10 years ago was someone who had seen maybe five or 10 cases,” he says. “I’m not calling myself an expert, but in West Africa, I was seeing hundreds of cases a week.”

One of Kumar’s own lessons was that on the ground, the disease rarely caused the most serious symptom: blood loss. “These people weren’t bleeding from their eyes or nose, the symptoms were more like vomiting and diarrhoea. But the death rates were the same.”

Working in personal protective equipment or PPE was vital to keep medical staff from contracting the disease themselves. But in the sweltering tropical climate this cumbersome garb made doing their job even harder. It also had an enormous psychological effect on those trying to give end of life care to dying patients.

“Working in PPE during that Ebola crisis, you realise it takes away that human touch side of medicine,” says Kumar. “As a medical student you’re taught to put your hand on a patient’s body when you’re talking to them. You can’t  do that the same way when you’re wearing PPE.”

Tracing infected people and who they came into contact with is a vital part of pandemic prevention

That same struggle is being beamed into our living rooms every day, as we see footage of nurses and clinicians in PPE trying to keep Covid-19 patients alive, covered in protective gear which makes it all the more difficult to make human connection.

Kumar says the Ebola outbreak could easily have been much worse, but what worked was “political will, media attention and innovation and research, which came up with vaccines and treatment. If Ebola erupts again, we will be able to squash it.”

Every pandemic is a classroom; each outbreak teaches a new lesson. The current coronavirus pandemic is the first chance for health agencies to study how whole countries adapt to extended isolation.

“I spent nine months in isolation in Antarctica, and it’s both one of the best and one of the worst things you can do,” Kumar says.

After the initial coronavirus outbreak is contained, the new challenge may be dealing with the after-effects of isolation, which will continue long after the pandemic claims its last victim.

Source: https://www.bbc.com/future/article/20200422-how-disease-outbreaks-are-contained

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