Poliomyelitis is almost eliminated – unless some lab technicians get screwed up


In 1979, a Photographer Janet Parker contracted an illness that was no longer supposed to exist. At first, she thought she had the flu, but then she continued to get sick, have a rash, and went to the hospital, where doctors – incredulous – diagnosed her with smallpox. A year earlier, the World Health Organization had stated that "humanity has probably witnessed its latest case of smallpox," according to the report. The New York Times. That should have been true. But in a laboratory at the University of Birmingham under Parker's darkroom, a scientist was working hard to finish his research on viruses, before the authorities limited the number of institutions studying the disease almost dead. The scientist did not obey security protocols and the virus escaped through a conduit, killing Parker.

Smallpox is the only human disease that man has ever eradicated. But as shown in the story above, "eradication" is not as simple as a dictionary definition would suggest to a person. There is the difficulty of vaccinating people, which implies international collaboration, money and willingness – as well as the resolution of conflicts, culture and geographical barriers. Then you have to monitor and control the epidemics. Finally, it is difficult to find and contain all existing virus samples, which did not happen in 1979.

At the moment, officials are working on this problem to treat another nearly extinct disease: polio. So far this year, six cases of polio infection have been reported in Afghanistan and Pakistan – two of the three countries in the world where polio is still present. This is a dramatic drop from 1988, when the virus affected 350,000 people and when the World Health Assembly decided to ban the infectious disease, to which children are most at risk, from the general population. of the planet by the year 2000. The global eradication campaign has come close to temptation. eliminate the disease from the planet, but delicate scientific issues lie between a few cases and absolute zero.

You can not just look at the infection numbers and declare the victory. You should also make sure that the virus exists only in dedicated laboratories with extremely strict security protocols and empty it from any other scientific or medical center that may contain particles of the deadly infection. These laboratories are numerous. In the United States, an initial investigation in 2002 revealed that 56 US facilities had "potentially infectious materials", while 37 had "possibly" and "absolutely infectious" samples. Sometimes these labs do not know that this agent of death and paralysis is hiding in their freezers. In the worst case, an incident in one of these labs could endanger lives and undo decades of grueling public health work.

The onset of polio looks like nothing, nor the flu, and some children come out with no lasting effects. But one in 200 cases ends in paralysis and 5 to 10% of these cases lead to death when the respiratory muscles contract. In the United States, we do not think much about polio because we do not have to: the vaccines actually eliminated it here in 1979. After the creation of the Global Initiative for Poliomyelitis. In 1988, the number of cases dropped by 99% worldwide, with the eradication of poliomyelitis. 29 only in 2018. "Without our polio eradication efforts, the virus would have paralyzed more than 17 million people currently in good health," says Steve Wassilak of the Center for Disease Control and Prevention's Center for Global Health. .

The initial turn-of-the-century deadline can be passed without total annihilation, but in 2015, a world commission declared the eradication of type 2 virus (there are three types). After that, officials began eliminating the vaccine with live versions of this strain, which can cause outbreaks under certain circumstances.

Today, Anna Llewellyn, global CDC poliovirus containment manager, is helping to locate type 2 that may be in hiding. With this strain of extinct poliomyelitis in the wild and the remaining epidemics (those not caused by vaccines) only of types 1 and 3, the living virus only subsists in a few places. It's under the roofs of vaccine manufacturers, polio research labs, people with chronic infections and, most importantly, in facilities that do not realize that the virus is hiding in their samples. frozen. "Labs do not know they have polio equipment because they collect and test other viruses, parasites or bacteria," says Mark Pallansch, director of the CDC's Viral Diseases Division.

If these laboratories collected faecal, respiratory or sewage samples from places where polio had circulated, they might accidentally have poliovirus on their hands. And if they do not have safety protocols for such a dangerous disease, or do not follow their own protocols, a virus leak could occur. Errors of this kind are not unknown: A 2018 guardian An article, for example, revealed that scientists from Bristol University had accidentally sent the dengue virus live by mail, "because the person who packed the material did not know at all that it contained live dengue ". The investigation revealed that this was only one of the more than 40 "incidents" found in laboratories that the UK health and safety officer had examined between 2015 and 2017.

To discover these "potentially infectious materials", the Global Polio Eradication Initiative hosts a large table listing the dates and locations of wild poliovirus outbreaks, as well as each country's vaccination schedules with live virus. , so that laboratories around the world can digitize the database. see if their samples could come from an area prone to polio. "All countries have completed or are responding to these surveys," says Lllewellyn.

Some laboratories, which may have unwittingly collected polioviruses, initially find the process invasive, but containing an infectious agent is somehow a non-controversial goal. "Nobody wants to be that guy who lets polio come back into the world," she says. "Nobody wants children paralyzed."

Still, it's a new process, and not easy. "Containment in general, and this part in particular, is a ship that sails as we build it," she says. When researchers discover potentially infectious samples, three options are available to them: the lab can destroy them, send them to another laboratory that will contain them or become what the World Health Organization calls an "essential poliovirus facility" allowed own the virus. Some laboratories need to keep polio on hand so that they can continue to produce vaccines and diagnose.

The less there are such places, the better. "Wherever there is still a live virus, there is always a risk that it can come out of these specific facilities," says Pallansch. Pallansch's colleague, Steve Oberste, is leading a CDC lab which is one of 78 facilities considered essential in 26 countries. It was the second center in the world to pass the first hoop proposed by a world commission: obtain a certificate of participation. Then comes the certification "interim", then finally the real deal.

Nobody has had it yet, partly because it's a capital-p process. A document entitled Global Action Plan III outlines the necessary safeguards for laboratories, including the ones you can expect (and the pages and pages you can read yourself): Keep the virus safe type 2 locked and with limited access. Give access to inventory records only to those who need them. Keep type 2 totally separate from other types. Know what you would do if the worst, decontamination, happened Hiring a "Biohazard" Manager. "There are a lot of things like that," says Oberste, "where you have to be willing to go beyond what a lab would do, or what a good lab would do."

But now, when polio is finally almost completely gone, this is the most important time to keep the remaining death officers in sequestration. "We are about to achieve eradication, which is a truly rare moment in the specter of humanity, to say that we are able to eliminate from the surface of the earth something that caused so much suffering, "said Llewellyn. "The closer we get, the more devastating an exit would be."

Lockdown, however, seems imminent. "2019: the year of confinement," she says. "You heard it here the first time."

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