Polio, or poliomyelitis, is a crippling and deadly disease caused by the poliovirus.
The virus, which spreads through fecal-oral contact, lives in an infected person’s throat and intestines where it can cause paresthesia (feeling of pins and needles in the legs), meningitis, and paralysis. This disease is very scary, as it often leaves effects on the patient that last for the rest of their lives, and even those that do recover fully can develop post-polio syndrome later in life. However, because this virus’ only reservoir is humans, there is hope at eradicating this virus forever if everyone receives the polio vaccine. This seems like a no-brainer to me, as the effects of polio are still being felt very strongly around the world, and could be eliminated very efficiently by a simple vaccine.
There are two main types of vaccines used to protect against the polio virus: the IPV and OPV. The IPV, or inactivated poliovirus vaccine, is an inactivated form of the virus that is injected into a patient’s leg or arm in four separate doses. This vaccine has been utilized in the US since 2000 and provides 99% immunity to the virus. The OPV, or oral poliovirus vaccine is administered orally by receiving drops of the vaccine in the mouth, since that is where the virus enters and lives. Since 2000 however, only IPV has been used in the United States to eliminate the risk of vaccine-derived poliovirus that can occur with OPV. This decision was also based on the decreased risk of poliovirus being brought into the country and because the US is currently polio-free, however the OPV is still used in other parts of the world.
In December of last year, the Center for Infectious Disease Research and Policy (CIDRAP) announced an outbreak in six nations, including Pakistan which reported 91 cases in 2019 (a stark increase from 12 cases in 2018). The outbreaks have emerged as five new wild type 1 (WPV1) cases and two more circulating vaccine-derives poliovirus type 2 (cVDPV2) cases have been reported. The virus, which flies under the radar for many first-world, unaffected countries, is still very much a global public health concern according to the WHO. The virus continues to mutate as it circulates, making it even more vital that as many people as possible are vaccinated to prevent not only its spread but also its evolution. The more people that we can reach with these vaccinations, the greater the chance that we can one day rid the world of polio.
micro biology 