According to the World Health Organization, the poliovirus has been eradicated in almost every part of the world; however, with the recent reports of increased detection of the poliovirus in wastewater, many health officials are worried that this long-forgotten virus may make its return. Here’s why they’re concerned and what they’re doing about it.
What is Polio?
Polio is a highly contagious viral infection that primarily affects young children. The virus is transmitted through contact with contaminated feces, and can cause severe paralysis and even death. There is no cure for polio, but it can be prevented through vaccination. In recent years, there have been only a handful of cases of polio reported in the United States. However, there has been an increase in the number of cases reported in other parts of the world, particularly in developing countries.
What are Wild Polioviruses (WPVs)?
Wild polioviruses (WPVs) are viruses that can cause polio, an infectious disease that can lead to paralysis and even death. There are three types of WPVs, and all are highly contagious. The last recorded case of WPV was in 2015, but there have been several outbreaks of vaccine-derived polioviruses (VDPVs) since then. VDPVs are created when the live attenuated virus used in the oral polio vaccine mutates and regains its ability to cause disease. While most people who catch VDPVs will not develop symptoms, some will develop a mild form of polio. In rare cases, VDPVs can cause severe polio, which can lead to paralysis or death.
What are Vaccine-Derived Polioviruses (VDPVs)?
Vaccine-derived polioviruses (VDPVs) are polioviruses that have mutated from the strain used in the oral polio vaccine. The oral polio vaccine is made from live, attenuated viruses and is given to children around the world to help protect them from poliomyelitis (polio). In some rare cases, the attenuated viruses can revert to their virulent form and cause disease. VDPVs have been responsible for outbreaks of polio in countries where vaccination rates are low. The most recent outbreak of VDPV occurred in 2014 in Sudan.
Why should I care about VDPVs?
When poliovirus was declared eradicated in 1980, it was a monumental moment in public health. But now, there are reports of the virus appearing in wastewater samples around the world. So what’s going on?
Are wild WPVs and VDPVs making a comeback in my country?
There are several confirmed cases of poliovirus in wastewater around the world. This has led to some concern that the virus may be making a comeback. However, it is important to remember that there are two types of poliovirus: wild and vaccine-derived.
Wild polioviruses are strains of poliovirus that circulate naturally, causing paralytic disease. Vaccine-derived polioviruses, on the other hand, develop from oral polio vaccine (OPV) — a live but weakened vaccine which contains attenuated (or weakened) strains of wild polioviruses. The key difference between these types is that OPV is able to replicate and spread within humans, whereas WPVs do not. Thus OPV poses no threat to those who are immunized with it and can only cause infection if someone is exposed to an immunized person excreting live vaccine virus via their stool.
How do these viruses get into drinking water supplies?
There are several ways that viruses can enter drinking water supplies. One is through sewage and wastewater. If these waters are not treated properly, they can contain harmful viruses like poliovirus. Poliovirus is a highly contagious virus that can cause paralysis and even death. It is spread through contact with contaminated food or water. Symptoms include fever, muscle weakness, and paralysis. There is no cure for poliovirus, and it can only be prevented through vaccination. In recent years, there have been outbreaks of poliovirus in countries where vaccination rates are low. These outbreaks are a reminder of how important it is to maintain high vaccination rates to protect against this potentially deadly virus.
Can polio transmission be prevented by proper sanitation and hygiene practices, or by treating water with chlorine?
Sanitation and hygiene practices are important for preventing the spread of polio. However, it is also important to treat water with chlorine to kill the virus. This is because the virus can survive in water for weeks. In addition, people can become infected with polio through contact with contaminated food or surfaces. Therefore, it is important to practice both sanitation and hygiene measures to prevent the spread of polio.
The take-home message…
The poliovirus is a serious disease that can cause paralysis and death. Though it has been mostly eradicated, there have been recent cases of the virus popping up in wastewater. This has led some to wonder if the virus is making a comeback.