Pre-empting pandemics
An ounce of prevention
As new viruses emerge in China and the Middle East, the world is poorly prepared for a global pandemic
Apr 20th 2013 | Bangkok and New York |From the print edition
IN FEBRUARY an 87-year-old man was admitted to hospital in Shanghai. What started as a cough progressed to a fever. One week later, unable to breathe and with his brain inflamed, he died. Shortly afterwards, a 27-year-old pork butcher was admitted to the same hospital with similar symptoms. He died too, within a week. A 35-year-old housewife who went to hospital in Anhui on March 19th lasted only slightly longer. On March 31st officials confirmed these were the first three cases of a strain of influenza, H7N9, that had never before been seen in humans.
The government responded quickly—a far cry from its reaction, ten years ago, to a similar cluster of cases in Guangdong. That infection turned out to be SARS (severe acute respiratory syndrome). At first, officials tried to hide that disease. The deceit served to ensure its spread and it went on to kill nearly 800 people. Much has changed in the past decade. This time officials quickly posted H7N9’s genetic sequence, then published a detailed report in the New England Journal of Medicine.
Even so, H7N9 has infected at least 82 people and killed 17 of them. The virus’s path of transmission is not well understood. The recent detection of H7N9 in a boy with no apparent symptoms suggests people can carry the virus unwittingly. Meanwhile a new coronavirus (the family of viruses that SARS belongs to) is circulating in the Middle East. It has killed 11 people since it was noticed in September. Though Saudi Arabia has welcomed some foreign investigators, other scientists claim the country should be more transparent.
Be prepared
These cases illustrate both how far the world has come, and how far it still has to travel, on the journey towards building a system that can identify new infectious diseases and snuff them out before they become threatening. As the case of AIDS shows, a novel pathogen that spreads around the world unnoticed by the medical authorities can wreak havoc. More recently, cheap air travel has proved a boon to pathogens keen for a global tour. Fortunately the world has learned from the cases of SARS, H5N1 bird flu (in 2005) and H1N1 swine flu (in 2009). Systems are being put in place to spot potentially pandemic diseases and stop them quickly. These systems, though, are still piecemeal. At present it looks unlikely that either H7N9 or the new coronavirus will become pandemic. But if they do—or if some other powerful new virus or bacterium emerges—it is unclear whether the world will be ready.
SARS and H5N1 gave people a shock, and in their wake a lot of progress has been made—and not only in China. In 2005 the members of the World Health Organisation (WHO) agreed on a new set of International Health Regulations, with rules for responding to outbreaks that are of global concern. For example, all members must alert the WHO to any risky-looking pathogen that might move beyond their borders. The regulations also include measures to dissuade people from imposing unnecessary restrictions on travel and trade. In the past, fear of such bans discouraged governments from reporting outbreaks. Meanwhile individual countries have started making their own plans for dealing with a pandemic. As of 2011, 158 had official provisions in place.
Surveillance has moved on by leaps and bounds, too. ProMED and HealthMap, two online reporting programmes at the International Society for Infectious Diseases and Boston Children’s Hospital respectively, use a range of sources to provide quick information on emerging threats. Google Flu Trends, run by the eponymous internet firm’s charity, monitors flu-related searches to estimate the disease’s prevalence. Such electronic systems complement conventional epidemiology, rather than replacing it (and are not always reliable; in America’s most recent flu season Google Flu Trends overestimated the number of those sickened). But traditional surveillance methods have improved, too.
Improved techniques, for instance, allow segments of DNA to be amplified rapidly, so viruses can be identified quickly. The cost of full genetic sequencing continues to fall. And countries’ surveillance efforts are now better co-ordinated. A model of co-operation can be seen north of Bangkok, where Thailand’s health ministry includes a National Influenza Centre. As one of the WHO’s designated regional laboratories, it tests samples from the whole of South-East Asia. This laboratory has also been supported for the past decade by America’s Centres for Disease Control and Prevention (CDC), an organisation well equipped to identify new medical threats. (It was the CDC that spotted AIDS.)
Many countries are better equipped than before to respond to an outbreak. America leads the way. The authorities have stockpiled 68m courses of antiviral drugs, 18m respirators and 31m face masks, and are investing in research to create better ones. The Biomedical Advanced Research and Development Authority (BARDA), an American government agency, contracts with companies to develop new ways to counteract biological threats. It has 130 products in development, including 45 for influenza.
The world’s biggest cities, often with aid from national governments, have honed their strategies, too. Shanghai watches for 15 categories of infectious disease at more than 5,700 sentinel sites. It has several emergency plans, tailored for outbreaks of different intensities. New York collects data from hospitals, laboratories and even pharmacies, to look for signs of new infections. The city cannot forcibly vaccinate its citizens, but it can order the unvaccinated to stay at home.
Even such extraordinary measures, though, may be ill-matched for a virus. H1N1 proved how much can go wrong. It was contagious but not particularly deadly, so officials were confused about how to convey its risks. Research published in the Public Library of Science on April 15th estimates that half the Tamiflu (an antiviral drug made by Roche) prescribed in England at the time of the H1N1 outbreak went unused, based on an analysis of traces of the drug in sewage. Vaccines took months to deploy, delayed by fundamental problems (the time needed to develop them) and trivial ones (American shipments had to wait for the pallets carrying vaccines to receive a fumigation certificate). An independent committee issued a discouraging review of the WHO’s response. “They made it very clear”, says Keiji Fukuda, the WHO’s top influenza official, “we are not ready for anything big.”
Since then the WHO and others have tried to improve things. In 2011 the WHO’s members created a new framework for sharing flu viruses—in 2006 Indonesia refused to share samples of H5N1 with the WHO out of concern that companies would use an Indonesian virus to develop treatment unaffordable to Indonesians. GlaxoSmithKline is the first company to sign a deal with the WHO under the new framework. The pharmaceutical giant will donate 7.5% of its vaccine production in the event of a pandemic. A further 2.5% will be sold at tiered prices, depending on a country’s income.
There is also new capacity to make the vaccines themselves. Last year BARDA awarded contracts for three new centres, to be led by Novartis, Emergent BioSciences (a firm in Maryland) and Texas A&M University, in collaboration with GlaxoSmithKline. These will develop and manufacture medical countermeasures, including vaccines. In November Novartis won approval for the first flu vaccine made from cultured cells rather than eggs—a technology that will help produce vaccines more quickly. There has also been progress in poor countries. The WHO has given grants to flu-vaccine manufacturers in 14 countries. Four of these are ready to go.
And researchers continue to test new tools that may help. For example, Marta González of the Massachusetts Institute of Technology has modelled how diseases spread by plane. In the early days of an outbreak, such models may help officials decide which routes to cancel to contain a virus. America is paying scientists to patrol rapidly changing environments in Africa, Asia and Latin America, where viruses are prone to hopping from beast to man. The hope is that the scientists will find dangerous viruses early, before they spread.
Next candidate…
There remains, nevertheless, much to be done. Many countries now have plans to prepare for a pandemic, but it is unclear which are operational. Dr Fukuda estimates that the world has the capacity to make enough vaccine for about 2 billion people—an improvement, but still short of what might be needed. Adding to the problem, governments are hardly flush with cash. The WHO has an influenza budget of $7.7m, less than a third of what the city of New York devotes to public-health emergencies. The main question is whether progress will continue, and whether it will pre-empt a more serious threat.
It is hard to say if either H7N9 or the new coronavirus will be pathogens that put the world to the test. The coronavirus in particular is still poorly understood. Ron Fouchier of the Erasmus Medical Centre in the Netherlands was the first to sequence its genome. He annoyed Saudi Arabia by patenting the result (though gene patents are a controversial area anyway—see “Natural justice” at the end of this section). He argues that the Saudi government should be more forthcoming with information. Saudi officials say they are working as quickly as possible and are collaborating with foreign epidemiologists.
The work around H7N9 has been relatively transparent. China has already shipped samples of the virus to laboratories all over the world. But the virus itself is still spreading in China, and people continue to die. Vaccines, once developed, may be ineffective. “H7” and “N9” refer to particular types of two proteins, haemagglutinin and neuraminidase, that help influenza viruses invade host cells. Other H7 vaccines have not created a strong immune response, according to Michael Osterholm of the University of Minnesota. It is also unclear if the virus may become more contagious—at the moment it does not seem to jump from person to person. Last year two groups of scientists, one led by Dr Fouchier, described specific mutations that might make H5N1 transmissible from human to human. H7N9 contains mutations implicated in this switch. If the virus mutates further, it might become airborne. And if that did happen, the world’s pandemic-protection system might be put to the test quite suddenly.
From the print edition: Science and technology http://www.economist.com/news/science-and-technology/21576375-new-viruses-emerge-china-and-middle-east-world-poorly-prepared/print