Controlling or Eradicating an Infectious Disease Through Vaccination

General Perception of FMD: 

Recently, on Whatsapp, there was heated debate on Foot and Mouth Disease Control Program in India and the summary of the discussion was that although the GoI has spent a lot of funds, FMD cases continue to be reported. The tone of criticism was that due to government apathy the program has failed to deliver. Another group brought up the point of corruption leading to vaccine failure. For such programs instead of voicing a damning verdict, the veterinarians should examine the issue dispassionately. In this blog, I present my analytical observations and interesting interaction with topmost IT authority.

FMD Control Program:

An important initial point to consider is the target objective; was its control of the disease or eradication of the disease. As per the information is given on the GOI website the project on FMD is not disease eradication but ‘Progressive Control’. The program also stipulates other activities, namely;

(a) surveillance of immune status in sera samples collected from 10 randomly selected villages in each district 10 days before and 21-30 days after vaccination.

(b) isolation and containment of sick animals after treatment, (c) issuing of health cards to each animal.

(d) restriction of movement of animals in the event of outbreaks and (e) isolation and containment of diseased animals after treatment.

Against these objectives, we examine whether the project is being implemented successfully.

FMD Mass Vaccination Program:

The approach to project implementation is ‘progressive control’ which means that with vaccination disease incidence will be reduced in the first instance followed by a lower incidence of outbreaks followed by eradication or eradication. For a disease like FMD, this approach is practical because there are different strains and variants of the virus. There is a general rule that when in a population few animals are vaccinated, disease is prevented in immune animals, whereas when more than 80% animals are vaccinated and immune at a given time, outbreaks of the disease will be prevented whereas when the entire population is uniformly immune then the causative agent will be eradicated.

In order to achieve eradication, it is necessary to vaccinate all susceptible animals on the same day, as it is done in the polio eradication program. For polio, such a program was possible due to the availability of a safe oral vaccine which could be administered even by volunteers.

The problem in Indian FMD control program is that there is no way to identify vaccinated and unvaccinated animals as the data of individual animal vaccination status is not maintained. Hence when FMD is reported, there is only anecdotal evidence to know if the animal is in the immune status window. Without the availability of this information, it is difficult to blame the vaccine for failure. In many countries, if not an individual animal, premises data is maintained to overlay vaccinated premises over disease outbreak.

To this extent, the program appears to be defective. For monitoring the success of such a huge program, disease reporting network must be very robust, which is not the case in India. For fear of backlash, veterinarians do not report disease outbreaks. The reason sounded is that if a disease or outbreak is reported, the veterinarian is held responsible. This must change, the administrators must encourage and reward veterinarians for correct reporting of important diseases.

Since vaccination data in states is not available it is difficult to comment on whether 80% population is being covered and with all probability, the answer is no. It is, therefore, wrong to evaluate the project considering continued disease outbreak. The criteria here will be to see if disease incidence rate has come down. There are also complicating factors such as more than one strain and variants, mutation and change in virus antigenicity and movement of animals that dilute proportion between vaccinated and unvaccinated animals.

An important factor overlooked is that unless all susceptible species of animals are vaccinated in the premises, the virus will continue to thrive in premises and population and whenever immune status is compromised disease incidence will be reported.

NIC and NADRES on FMD: 

Most of the vets in India are aware of the National Animal Disease Referral Expert System (NADRES) platform developed to report disease incidence data to be collated nationally. As a vet interested in preventive medicine, I was keen to understand the platform and link the same to the herd management system that I was developing. In a seminar in Pune, I came in contact with a lady staff from NIC New Delhi who was involved in the development and rolling out of the system. After listening to my talk, she invited me to Delhi to interact with her boss DDG so that field disease data linking could be planned. On the appointed day I reached in time and waited for him for nearly 4 hours. He finally met me a late evening and the outset he told bluntly ‘not interested in any presentation or demo’.

I was shocked to hear from him how the disease data collection was developed. It was on the call center, the farmer would call the operator and register any sick animal, and the operator will pass the information to local para-vet or vet. He also said NADRES also has the facility of registering animals in heat and after call registration, the para-vet will be informed on the phone. Now, this was happening even though they did not have para vets or vets registered with contact details. To my question as to how without diagnosis and vetting of a competent veterinary authority a disease can be declared on a public platform, he had no answer.

When I asked him how would you know if the para-vet has gone there to treat or do AI, he had no answer. All he said that in case para vet or vet did not attend the farmer can file RTI with the Department.

When he understood that I caught him on the wrong foot, he started blaming the vets and the departments, that they did not guide NIC properly. From the information, I gathered the NIC charged the Government several crores for a very shabby non-performing platform. I hope over a year this might have improved. The point I am trying to make here is that our livestock projects look perfect on paper but when it comes to implementation there remain loop-holes which makes the whole program unsuccessful.

Way Forward:

So, what do we do, sit resigned to the present situation? The veterinarians must realize that unless they participate and make animal identification, premises registration and data recording program successful, very little can be achieved and whatever achieved can’t be quantified. We have to be honest and accurate in reporting problems because otherwise, no planning is possible. Lastly, in the case of food animals, we will have to move away from hospital-doctor mode and implement productivity enhancement services. I know our veterinarians even with best of intentions are constrained by antiquated and redundant policies.

Please forward your comments and views on info@indiancattle.com Do suggest on what topics you want us to publish blogs.

Dr. Abdul Samad

(Ex-Dean and Director, MAFSU, Nagpur)