NB Health Care

Wednesday
June 8
2016

Dr. Melvin Sanicas

With Another Pandemic Looming, Let’s Change Perspective

Launch of specific insurance market a step in right direction

 

With the Ebola outbreak last year and the Zika virus currently occupying researchers and doctors in South America, Central America and the Caribbean, people aren’t paying attention to the threat of an avian influenza (AI) pandemic sweeping the world. But they should be, given the unique characteristics of AI viruses and their expanding global presence.

Avian influenza is a “zoonotic infection” – transmitted to humans via animals – caused by viruses that are adapted to affect birds. It primarily affects poultry such as chicken and ducks; however, other types of birds may also be affected. Most human infection predominantly occurs via direct contact with infected birds or poultry – their droppings, contaminated environments (i.e. poultry markets) or handling of live or dead birds. The AI virus strains are distinct from human seasonal influenza and humans have little immune protection, as this type of viral infection is relatively uncommon.

Until now, the H5N1 strain of influenza virus has been responsible for most human illness due to AI. However, H7N9 may soon rival H5N1 as a potential cause of a human pandemic.

H7N9 had not been seen in humans until infections were reported in March 2013 in China. It had previously been isolated in birds with outbreaks in Japan, the Netherlands and the U.S. Current evidence suggests that this virus has not acquired the ability to regularly transmit from human to human, except for small clusters of reported cases which predominantly involved health care workers. While a small proportion of human H7N9 illnesses have been mild, most patients have become seriously ill, developing severe respiratory symptoms that require hospitalization and intensive care, and 32 percent have died. Most of those who contracted the virus had recent exposure to live poultry or potentially contaminated environments, particularly markets where live birds have been sold.

Cases have been reported in Canada (two), Hong Kong (15), Malaysia (one) and Taiwan (four). In one case in Hong Kong, in April, the patient was an 80-year-old man with pre-existing illnesses. He developed a cough and headache and his symptoms evolved into fever and disorientation, after which he was admitted to the hospital for pneumonia. He was later found to be positive for H7N9. Further investigation revealed he had traveled to mainland China and purchased/slaughtered poultry from a market.

Researchers conducted genetic analysis from an H7N9 sample and found that the virus has genetic mutations from previous AI strains that allow for more efficient spread among humans. Human-to-human transmission is still rare; however, it has an increased likelihood in a hospital setting. The New England Journal of Medicine reported that in January 2015, a 28-year-old male infected with H7N9 after repeated exposure to live poultry was admitted to a hospital in Shantou, China, and during his stay two doctors who had close contact with him also became infected with the virus. Fortunately, all three patients recovered.

H7N9 can infect poultry without causing clinical symptoms, which makes it difficult to monitor its spread. In live bird markets, poultry from different farms often mix together and animals are sent from one farm to another, allowing the potential exchange of viruses.

H7N9 tends to spike in the winter, and there were fewer cases this winter than in previous years. This reassured some health officials that the situation is under control, but this could change at any moment given AI’s ability to rapidly change. The fear is that further genomic mutations will lead to the virus binding to human cells and increased human-to-human transmission.

There is currently no vaccine to protect against H7N9 but researchers are working to develop a vaccine candidate virus that could be used to make one if needed. However, even if a safe and effective H7N9 vaccine becomes available, it will not be easy to convince farmers in affected countries to vaccinate their flocks against a pathogen that does not cause significant losses or clinical disease.

A number of the vaccine manufacturers have used adjuvants – a substance that enhances the body’s immune response – to boost the impact of flu vaccines. During the 2009 H1N1 pandemic, Canada and a number of European countries bought vaccine that included an adjuvant. However, since that pandemic, studies in several European countries have linked use of GlaxoSmithKline’s adjuvant, AS03, with an increased incidence of narcolepsy among young people. Countries with pandemic flu vaccine contracts are watching how the outbreak unfolds before deciding on whether to place an order for an H7N9 vaccine. Meanwhile, vaccine manufacturers are using their production facilities to make seasonal influenza vaccines for the Northern and the Southern Hemisphere flu season, and the U.S. Centers for Disease Control and Prevention recommends oseltamivir (Tamiflu®) and zanamivir (Relenza®) for treatment of H7N9.

The World Bank recently announced the launch of the world’s first insurance market for pandemic risk – a $500 million, fast-disbursing insurance fund to fight deadly pandemics in poor countries. Japan, which holds the G7 presidency, committed the first $50 million in funding toward the new initiative. In the event of a pandemic, funds will be released quickly to affected poor countries and qualified international first-responder agencies. The Pandemic Emergency Financing Facility was developed with the World Health Organization and reinsurers Swiss Re and Munich Re, which are acting as insurance providers, and is limited to certain classes of infectious diseases most likely to cause major outbreaks, including several types of influenza, SARS, MERS, and other deadly viruses such as Ebola and Marburg.

The idea for this new facility came about after the slow response to the Ebola outbreak in 2014. World Bank President Jim Yong Kim said, “The recent Ebola crisis in West Africa was a tragedy that we were simply not prepared for. We can’t change the speed of a hurricane or the magnitude of an earthquake, but we can change the trajectory of an outbreak. With enough money sent to the right place at the right time, we can save lives and protect economies.”

Four global commissions reviewed the recent Ebola virus disease epidemic and consistently recommended strengthening national health systems, consolidating and strengthening the World Health Organization outbreak response activities, enhancing research and development for treatments, and emphasized the role of global leaders – the United Nations, World Health Assembly, G7 and G20 – in maintaining continuous oversight of global health preparedness.

Another pandemic is going to happen, but nobody can accurately predict when and where, and which virus – whether it be H7N9 or another influenza strain. We cannot prevent the emergence of new viruses – that is evolution at work through mutation, recombination, reassortment and natural selection – but we can take measures to prevent small epidemics from becoming big epidemics. We should change the way we view epidemics, acknowledging that fighting them costs much more than preventing them, and invest in infrastructures for epidemic preparedness, most especially in poorer countries. Mechanisms such as the Pandemic Emergency Financing Facility will enable funding and experts to go to the sites of outbreaks before they spin out of control.

Dr. Melvin Sanicas is a Global Health Fellow and program officer at the Bill & Melinda Gates Foundation.

Top photo: A Vietnamese poster warning about H5N1, by Joe Gatling via Flickr.

Homepage image by Tony Bowden via Flickr


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Health Care
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global health, health care, infectious diseases, pandemics, pharmaceutical industry, public health, vaccines