We know OPV vaccine is there for polio which is a viral disease then why this question is there "why it is difficult to develop vaccine for viral disease".
We know OPV vaccine is there for polio which is a viral disease then why this question is there "why it is difficult to develop vaccine for viral disease".
Polio vaccine is made by culturing polio virus on kidney cells of monkey under the specific laboratory conditions. But it doesn't means that vaccine for rest of the other viral diseases can be prepared in the same way.
Viruses have different forms and they can only grow, divide and live inside the body of a host. They cannot survive without a host. Thus, it is difficult to culture other viruses outside host’s body or in a lab. If possible, the expense will be very high. More over viruses are mutating (changes occur in genes) continuously, so the vaccines which act once successfully may not be effective next time. For all these reasons it is difficult to develop vaccines for all viral diseases.
Polio vaccine is made by culturing polio virus on kidney cells of monkey under the specific laboratory conditions. But it doesn't means that vaccine for rest of the other viral diseases can be prepared in the same way.
Viruses have different forms and they can only grow, divide and live inside the body of a host. They cannot survive without a host. Thus, it is difficult to culture other viruses outside host’s body or in a lab. If possible, the expense will be very high. More over viruses are mutating (changes occur in genes) continuously, so the vaccines which act once successfully may not be effective next time. For all these reasons it is difficult to develop vaccines for all viral diseases.
