A collaborative study was conducted by ICMR-National Institute of Virology, Mumbai Unit, ICMR-National Institute of Immunohaematology, and World Health Organization, India, and screening for the excretion of poliovirus was done for all children with inborn errors of immunity (IEI). Among the group was a 7-month-old baby (male) from Kerala who was found to have iVDPV type 1 in his stools. What makes the case rare is the fact that the baby has passed it on to his father as well. Read for more. 

History Of Oral Polio Vaccine 

From being one of the most feared diseases on the planet to having its global incidence lowered by almost 99 percent, Poliovirus has resulted in several epidemics from 1948 to 1955. Soon, the first polio vaccine was introduced by Dr Jonas Salk, IPV or Inactivated Polio Vaccine, which was injectable and made up of a combination of inactivated strains of all 3 subtypes of poliovirus. Later on, in 1961, Dr Albert Sabin developed a new version of the vaccine which had to be taken orally and consisted of live but attenuated strains of the 3 subtypes of poliovirus. This was OPV or Oral Polio Vaccine, which is widely used across the globe to date. 

What is iVDPV?

Immunodeficiency-Related Vaccine-Derived Poliovirus (iVDPV) is the term used for polioviruses that mutate from OPV strains. This is commonly seen in individuals who have compromised immunity owing to an immunodeficiency disorder. Unlike healthy individuals who are able to clear out the strains of viruses from their bodies after receiving their dose, those with immunodeficiency disorder are unable to get rid of these. As such they continue to replicate in their body and can even be transmitted to others, giving rise to the risk of further outbreaks. 

Polio Transmission From Child To Father

According to the National Library of Medicine, A 7-month-old baby from Kerala with inborn errors of immunity (IEI), who presented with the signs of pneumonia and lymphopenia was diagnosed with severe combined immune deficiency (SCID) due to a missense variant in the RAG1 gene. 

The baby received 2 doses of OPV, one at birth and another at 20 weeks. 4 samples were taken at an interval of 4 weeks and they tested positive for iVDPV type I. Stool samples of the parents were also tested and while the mother tested negative, the father, who is a 32-year-old, tested positive. Despite being asymptomatic, his stool samples had traces of iVDPV, clearly suggesting that he had contracted it from his child. Doctors performed a haploidentical hematopoietic stem cell transplant to save the child but lost him after 3 weeks.

Oral Polio Vaccine has helped to save countless lives over the years and helped to eradicate polio to an extent where it is almost rare, however, attention needs to be paid to the potential risks which include transmission of iVDPV from immunocompromised children to people around them, as well as the complications seen in such children. 

Sources 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11281642/

https://iple.unicef.in/pages/history.html