According to the cover story in last week’s issue of Time, “The number of new diseases per decade has increased nearly fourfold over the past 60 years, and since 1980, the number of outbreaks per year has nearly tripled” (“The Next Pandemic” By Bryan Walsh, Time, May 15, 2017). Pandemics spread because of factors such as urbanization, conflict, sow response, natural disasters and air travel, the article said, and microbes that cause them evolve about 40 times as fast as humans do. “An infection in all bu the most remote corner of the world can make its way to a major city in a day or less,” the article said.
The U.S. Centers for Disease Control (CDC) stated that H7N9 – avian flu -- is the flu strain with the greatest chance of causing a pandemic, a global infectious disease outbreak. The Gates Foundation is donating $100 million to the Coalition for Epidemic Preparedness (CEPI) to expedite the development of vaccines against diseases that can cause pandemics.
A Washington Post article by Lena H. Sun (“With bird flu surging, U.S. needs to do more to prevent possible pandemic, GAO says”, May 12, 2017), claimed that “If the United States were suddenly facing a potential avian influenza pandemic, just one U.S. manufacturer could be counted on to make human pandemic flu vaccine…Until an emergency arises only voluntary and often inadequate measures by poultry producers are in place to protect flocks, according to a new Government Accountability Office report.
H7N9 has caused numerous human infections in China recently. Most of the nearly 200 people who have died had direct contact with poultry or poultry markets. Health officials around the world are especially concerned about the spread of the disease because of the large increase in cases and the tendency of the virus to change. The GAO report recommends controlling the virus in poultry to reduce human infection and prevent a pandemic. The report discussed Agriculture Department measures after avian flu outbreaks in 2014 and 2016, “which resulted in the deaths of millions of domesticated poultry in 15 states and $2 billion in costs to the federal government and U.S. economy.” The report concluded that federal agencies face “ongoing challenges and associated issues” in mitigating the potential harm of avian influenza.
According to the report, the Agriculture Department cannot require poultry producers to take preventive biosecurity measures to keep avian flu from spreading from farm to farm. Commercial flocks raised outdoors and backyard flocks run a greater risk of contact with wild birds infected with avian flu. While pandemic flu vaccines for humans can be made using a number of technologies, the most common approach is to grow virus cultures in fertilized chicken eggs. Although the Department of Health and Human Services has “a stockpile of influenza vaccines supplied by four companies,” only one company has an egg-based vaccine manufacturing facility in the United States.
The other problem is that the current strain has split into two distinct genetic lineages, making the stockpiled strain only part of the solution. “Constant change is the nature of all influenza viruses,” concluded Wenqing Zhang, director of the World Health Organization (WHO) global influenza program.