Modern Epidemics. Salvador Macip. Читать онлайн. Newlib. NEWLIB.NET

Автор: Salvador Macip
Издательство: John Wiley & Sons Limited
Серия:
Жанр произведения: Медицина
Год издания: 0
isbn: 9781509546589
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functioned and why it had been so deadly, in the hope of being able to design better drugs and vaccines against future pandemics.

      The work of Dr García-Sastre and his colleagues aroused the fears of both citizens and other scientists who believed that it would be dangerous to ‘resuscitate’ such a terrible virus. Others believed that the chances of the new virus escaping weren’t very high, while the authors of the study argued that the benefits greatly outweighed the possible risks. Naturally, the safety measures around people handling these kinds of microbes are exhaustive, and accidents are therefore unlikely. Moreover, it’s believed that today’s population has more immunity to the virus than people did in 1918 because, since then, the circulation of variants similar enough to the original one might have generated a certain response that could protect us. The virus has been studied ever since that time without any notable incident.

      The success in terms of healthcare has been due to vaccination campaigns which, as I will explain below, began in the nineteenth century. The last smallpox patient was registered in the United States in 1949, while the world’s last natural infection was seen in Somalia, in 1977. Vaccinations which, in themselves, could give rise to small outbreaks of smallpox, ceased to be given not long afterwards. In May 1980, the 33rd World Health Assembly officially declared the world free of smallpox.

      Poliomyelitis, more simply known as polio, is a disease that causes paralysis in 1 per cent of those afflicted by it because the virus responsible destroys nerves. The most frequent kind is paralysis of the legs, but if the nerves controlling the muscles related with breathing are affected, it can be fatal. Some kinds of paralysis reverse in the first year but, after that time, few improve. It’s calculated that, at the beginning of the twenty-first century, between 10 and 20 million people had survived polio, with varying degrees of sequelae. In 90 per cent of cases there are no symptoms.

      Since the turn of the century, $6,000 million have been spent on preventing and controlling polio. In early 2009, a new initiative was announced to eliminate it from the few places where it still exists (especially Nigeria, India, Afghanistan and Pakistan) and thereby to make it history’s second eradicated disease. An investment of $630 million was made, donated by the Bill & Melinda Gates Foundation, Rotary International groups and the governments of Germany and the United Kingdom, which was distributed by the Global Polio Eradication Initiative (GPEI), part of the WHO. The strategy was mainly to increase vaccination of small children, as this is the most effective preventative. Although the hoped-for results haven’t yet been completely achieved, the experts are optimistic and believe that there is every chance that polio will end up disappearing altogether.

      Of the three existing variants of poliovirus, type 1 is the most aggressive. In 1999, type 2 was eradicated. Only a few samples were kept for study or continued production of vaccines. This might have been recorded as the second microorganism to be eliminated from the planet if it weren’t for the fact that, in 2005, it made a surprise reappearance in the middle of Africa. By 2008, it had resulted in thirty cases of paralysis and, by the middle of 2009, a further hundred, together with the possibility that it would start spreading to other areas. The origin of these new outbreaks was the vaccine that was supposed to eliminate it.

      Here are some of the famous people who suffered from poliomyelitis. Many of them survived without visible sequelae:

      Alan Alda

      Francis Ford Coppola

      Donovan

      Mia Farrow

      Frida Kahlo

      Joni Mitchell

      Doc Pomus

      Donald Sutherland

      Arthur C. Clarke

      Joe Dante

      Ian Dury

      Mel Ferrer

      Jack Niklaus

      Itzhak Perlman

      Walter Scott

      Neil Young

      The most famous polio patient in history, the president of the United States, Franklin D. Roosevelt, was most probably confined to a wheelchair because of another disorder, the Guillain-Barré Syndrome.

      This happens because the vaccine that is presently being used is the so-called OPV (oral polio vaccine), the one discovered by Sabin. It is very effective. The problem is that it’s made from attenuated viruses and it’s known that, in some cases, they revert to their active form, recover their aggressiveness and cause spontaneous outbreaks. Although it is relatively rare (seen in just one case among almost 8 million vaccinated people), this is precisely what occurred in 2005 with the vaccine against the type 2 virus. In 2009, there were 124 cases of paralysis in Nigeria caused by this vaccine.

      The main reason that polio is still around is the difficulty of vaccinating the entire population. In Nigeria, for example, the vaccination of children in the Islamic states of the north was halted for a while because of a rumour that the vaccine caused both infertility in women and AIDS. The most conservative religious leaders recommended that the population should not be vaccinated, and the