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Polio is almost extinguished – unless some lab technicians mess up



In 1979, a photographer named Janet Parker got a disease that was not supposed to exist anymore. At first she thought she had the flu, but then she became more and more ill, got a rash and went to the hospital, where doctors – disbelievingly – diagnosed her with smallpox. Only a year earlier, the World Health Organization (WHO) had stated that "humanity has probably seen its last case of smallpox," The New York Times . That should have been true. In a laboratory at the University of Birmingham near Parker's darkroom, a scientist had worked furiously to complete his virus research before the authorities stifled the number of facilities that screened the near-dead disease. The scientist did not follow the safety protocols, and the virus got through a canal and killed Parker.

Smallpox is the only human disease that humans have ever eradicated. But as the story above shows, "extermination" is not as easy as a dictionary definition would make anyone believe. There is an effort to vaccinate people, which includes international cooperation, money and will ̵

1; as well as overcoming conflicts, culture and geographical barriers. Then outbreaks are tracked and suppressed. And finally, there is the effort to find and curb every single sample of a virus that did not happen in 1979.

At the moment, officials are working on this problem for another nearly vanished disease: Polio. This year, there were six known cases of polio infections in Afghanistan and Pakistan – two of the three countries where polio has remained. This is a dramatic decline in 1988, when 350,000 people were attacked by the virus and the World Health Assembly decided to eliminate the infectious disease, most prone to children, from all over the world by the year 2000. The worldwide eradication campaign is nearing to wiping the disease off the planet, but tricky scientific questions are between few cases and absolute zero.

You can not just look at the infection numbers and explain the victory. You also need to make sure that the virus only exists in dedicated labs with compulsorily stringent safety protocols, and remove it from all other scientific and medical facilities that may contain particles of the deadly infection. Such laboratories are numerous. In the US, a first survey in 2002 found that 56 government agencies had "potentially infectious material," while 37 had both "potentially" samples and "definitely infectious" samples. Sometimes these labs do not know that this agent lurks in their freezers for death and paralysis. In the worst case, a mishap in one of these laboratories could jeopardize life and ruin decades of grueling public health work.

Polio's appearance feels like nothing or like the flu, and some children go through without any lasting effects. But one out of every 200 cases ends in paralysis, and 5 to 10 percent of these cases end in death when the muscles become tight. In the US, we do not think much about poliomyelitis because we did not have to effectively eradicate vaccines in 1979. With the creation of the Global Polio Eradication Initiative in 1988, global cases fell 99 percent to only 29 in 2018. "Without our polio eradication efforts, more than 17 million people who are currently healthy would be affected by the virus has been paralyzed, "says Steve Wassilak of the Center for Global Health's Centers for Disease Control and Prevention.

The original turn-around period may have passed without total annihilation, but in 2015, a global commission declared that the Type 2 virus (there are three variants) was eradicated. Afterwards, officials began to remove the vaccine from live versions of this strain, which under certain circumstances can itself lead to outbreaks.

Today, the help of Anna Llewellyn, a Poliovirus policewoman, helps hide Type 2 Containment Officer at the CDC. Since this polio strain is extinct in the wild and only outbreaks (which are not caused by vaccines) only in type 1 and 3, the living virus remains only in a few places. It stands under the roofs of vaccine manufacturers, in laboratories that conduct polio research, in people who suffer from chronic infections, and especially in facilities that do not recognize the viruses lurking in their frozen specimens. "Labs do not know that they have polio materials because they collect and test other viruses or parasites or bacteria," says Mark Pallansch, director of the CDC viral diseases department.

If these labs were carrying feces, respiratory or sewage samples from places where polio was circulating, they might accidentally have poliovirus on their hands. And if they either have no safety record for such a dangerous disease or do not follow their own protocols, it could come to a viral escape. Errors of this sort are not unknown: An article from the year 2018 Guardian revealed, for example, that scientists at the University of Bristol accidentally sent a live dengue virus to the post office because the person packing the material had, had no idea Live Dengue. "The investigation said it was just one of more than 40 laboratory mishaps that the UK Health and Safety Executive studied between 2015 and 2017. This table shows the date and location of outbreaks of wild poliovirus and the times when every country has live virus vaccinations, and labs around the world can search the database and see if their samples may come from a polio-prone area. "Each country has either completed or is in the process of conducting these surveys," says Lllewellyn.

In some laboratories that may have unwittingly collected polioviruses, the process is initially considered invasive, but to contain an infectious agent is a certain goal. "Nobody wants to be the guy, the polio back to the world Nobody wants paralyzed children. "

Still, it's a new process and not easy." Containment in general And this part in particular is a ship being sailed while we build it, "she continues. When researchers find potentially infectious samples, they have three options: the lab can destroy them, send them to another lab that will contain them, or become what the World Health Organization calls "poliovirus essential may own the virus. Some labs need polio to keep them vaccinated and diagnosed.

The less such spots, the better. "Wherever there are live viruses, there is still the risk that these special facilities will run out," says Pallansch. Pallansch's colleague, Steve Oberste, runs a CDC lab that is one of 78 key facilities in 26 countries. He was the second center worldwide that jumped through the first frame of a global commission: getting a certificate of attendance. Then comes the "interim" certification and finally the actual deal.

Nobody has gotten that yet – partly because it's a capital process. A document called Global Action Plan III contains the necessary safeguards the labs need to take, including some that you might expect (and pages and pages that you can read yourself): Keep the Type 2 virus locked and restricted Access. Allow access to inventory records only to those who need them. Keep Type 2 completely separate from the other types. Do you know what you would do when the worst – decontainment – happened. Assign a "Biorisk" manager. "There are many such pieces," says Colonel, "where you have to be prepared to go beyond what a lab would do – even what a good lab would do."

But now, when polio has finally almost disappeared, the most important time to lockdown the few remaining death agents. "We are about to realize the extermination, which is a truly rare moment in the spectrum of humanity, to say that we can wipe the face of the earth, causing so much suffering," says Llewellyn. "The closer we get, the more devastating would be a release."

Lockdown, however, feels instantaneous. "2019: the year of containment," she says. "You heard it here first."


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