Poliomyelitis (Polio) is an infectious viral disease which normally affect the CNS (Central nervous system) and can cause paralysis to any part of body. It can be temporary or permanent.
In this article we will talk about Polio Vaccine and its crisis. Polio stands for Poliomyelitis.
Read our article “Polio vaccine contamination: A matter of concern?” to know everything about this news.
Success in Polio eradication initiative:
As per WHO, number of cases die to Polio virus is progressively reduced from 350,000 (1988) to 22 (2017), which is around 99% reduction. It mainly affects children under 5 years. Children can die with irreversible paralysis of respiratory muscles.
Polio can be diagnosed with Throat secretion sample, Stool sample, Cerebrospinal fluid (Colorless fluid that surrounds your brain for protection) and Spinal cord.
Type of Polio Vaccine:
There are two types of Polio Vaccines which used to prevent Polio as per WHO.
1. Inactivated Polio Vaccine (IPV):
IPV is given by injection. Inactivated polio virus vaccine contains three polio virus strains-
a. Mahoney type 1
b. MEF-1 (Middle East Forces) type 2
c. Saukett type 3
It is administered via injectable route. The viruses are grown either in Vero cells or human diploid (MRC-5) cells and then concentrated, purified and inactivated with formaldehyde
Excipients in IPV are small amounts of antibiotics like neomycin, streptomycin and polymyxin B. Sometimes it contains preservative like 2-phenoxyethanol. Thiomersal cannot be used for IPV.
2. Oral Polio Vaccine (OPV):
OPV is Weakened/Attenuated polio virus. Most of the manufacture companies produce trivalent OPV using sabin vaccine seed. They grow the virus in culture of monkey kidney cells and vero or diploid cells. OPV is stabilised preparation of love attenuated polio viruses of sabin strains-
a. Type 1 (LS-c, 2ab)
b. Type 2 (P712, Ch, 2ab)
c. Type 3 (Leon 12ab)
Excipients in OPV are Streptomycin and neomycin, MgCl2. No adjuvants or preservatives are used.
As there is no cure for Polio, we can only prevent it with the help of these vaccines.
Here the point to be consideration is inactivated Polio Vaccines are very safe with just mild pain and redness at the site of administration.
Real concern is about Oral Polio vaccines are also safe but there are rare chances of cases of vaccines-associated paralytic poliomyelitis (VAPP).
Sometimes large production of Polio Vaccines without proper Quality control may give chance to contamination. This is serious concern as health perspective, since the individual who use contaminated Polio Vaccines will suffer most.
There are some instances when these types of contamination Polio Vaccines were used.
1. Rhesus monkey kidney cells used to prepare the polio virus vaccines were infected with the Simian Virus-40 (SV 40) in 1960.SV-40 was found in stocks of the inactivated polio vaccine (IPV) in use between 1955 and 1963 in USA.
2. In India, three batches with 1.5 Lakh vials have been found contaminated with type 2 polio virus. Recently, in Uttar Pradesh, Telangana and Maharashtra it was reported that contaminated Vaccines have been supplied and administered to children. The vaccines were manufactured by Gaziabad-based firm Biomed.
You can find the recent instance of contamination of OPV in our news section article
Hope this article gives an insight about Polio vaccines and its uses. Please ask your doubts in comment box below.