'Smallpox, the most serious threat'

Print edition : November 10, 2001

Is the country adequately prepared to respond to a bio-terrorist attack? "The situation in the country is pathetic," says Kalyan Banerjee, former Director of the National Institute of Virology (NIV), Pune, and a member of the erstwhile National Security Advisory Board (NSAB). A key member of the Indian team in the early years of negotiations on the verification protocol of the Biological and Toxin Weapons Convention (BWC), he explains:

"The remedy requires a long discussion and would involve several factors, starting from medical education and training in infectious diseases, the building of a surveillance system and a network of diagnostic laboratories, the provision of diagnostic reagents, serum banking, information network and above all, a professional and political will." Excerpts from Banerjee's responses to questions from R. Ramachandran over e-mail:

Which of the biological warfare agents - both plant and animal pathogens - pose a more serious threat from the perspective of a terrorist attack in India?

The nature of agents would depend upon when the operators wish to act. It would depend upon several factors, for example, population density, transport, standards of hygiene in the community, health care facilities, health intelligence and surveillance, the degree of immunity in the population against a pathogen, transmissibility of the pathogen, its natural seasonality, and so on. For India, as of today, smallpox is probably the most serious threat. The reason is that smallpox vaccination was discontinued in 1977. The whole population born after 1978 is unvaccinated and is thus susceptible. Even in people born before 1977, the immunity has waned considerably. The virus is highly contagious, is very easily transmitted from person to person and produces heavy mortality. The most important reason is that the virus exists in two laboratories of the world even today, and there is good reason to believe that at least one of them has weaponised the agent. We have been trying to get the stocks destroyed and make the WHO (World Health Organisation) declare that possession of the smallpox virus should be declared a crime against humanity, but so far this has been unsuccessful. After the global polio eradication programme, if the routine vaccination against poliomyelitis is discontinued, after 15 to 20 years, the position of immunity in the global human population would be somewhat like that for smallpox now. Then the polio virus would become a very potent bio-weapon. It is therefore absolutely necessary to destroy all stocks and potential sources of wild poliovirus everywhere in the world.

The next, of course, is anthrax. It is very easy to grow and the spores of the bacteria are very stable. The spores can be mixed with substances such as talcum powder and pulverised. This organism too has been weaponised. The other important bacteria that should be strictly monitored are Franscicella tularensis causing tularemia, Pasteurella pseudotuberculosis var pestis (which causes plague), drug resistant Shigella shigae, (causing dysentery), drug resistant cholera and the new variants of it.

Among viruses other than smallpox, one should bear in mind Rift valley fever (it may get introduced in India by natural methods also), Eastern and Western equine and Venezualan encephalitis viruses. These viruses are transmitted by mosquitoes, which are in plenty in India; they can also get transmitted by aerosols. There are other viruses such as the Hantaan group of viruses, which are transmitted through the urine and excreta of rodents and also through aerosols. Once these viruses are introduced into the country, they can cause perpetual problems. The rodent population in India is phenomenal. Introduction of yellow fever can also cause havoc in the Indian population.

Lastly, and the most important is influenza. It is now possible to produce a recombinant virus that can infect millions, but it certainly will go out of control and would not serve the propagators of bio-terrorism. This would require a very highly sophisticated laboratory and a vaccination programme of the people, which cannot be hidden.

For livestock, the most feared is the introduction of the rinderpest virus. It has been recently brought under control and a virulent strain can kill millions of head of cattle. A virulent strain of the foot-and-mouth disease is equally dangerous. So are some of the poultry viruses, which cause immense economic damage. In the past, the African horse sickness virus killed thousands of horses and mules of the Indian Army. A vaccine is available but a new strain would put the transport of arms and ammunition in the mountain regions in jeopardy.

For plants, wheat rot is the most feared agent. It has already been weaponised.

Lastly, biological warfare/ terrorism also includes the use of toxins. The toxin commonly spoken about is the botulinum toxin, which can be easily produced, even in a small laboratory. However, the more esoteric toxins, information about which is classified, require much work and sophisticated laboratories. These are not within easy reach of average terrorists.

Health Minister C.P.Thakur has stated that anthrax vaccine will be manufactured. Is that feasible considering the fact that only the United States military has the technology and is the sole producer of the vaccine in the world?

The Health Minister's decision to manufacture anthrax vaccine is certainly laudable. An anthrax vaccine for humans would be good. The veterinary people have been manufacturing small quantities for animals. But how good is it is not known. If a vaccine is made sui generis in India for humans, it is likely to take quite some time. If the Minister negotiates with the U.S. Army for the transfer of technology it would be excellent. However, we have witnessed the fate of the transfer of technology for the manufacture of the polio vaccine in India, so also that of the Hepatitis B vaccine and of the Japanese encephalitis vaccine. Looking at the fate of these vaccines, it does not make one very optimistic.

What kind of medical preparedness will be required to treat anthrax if there is an attack?

Anthrax is a very easily treated disease (specially the cutaneous variety). For the pneumonic variety, the problem is rapid diagnosis. Every case of fever and signs of pneumonitis is not likely to be anthrax. However, the common antibiotics, are effective. So far I have not come across any report of antibiotic resistance in anthrax. But, I must confess that my knowledge is very limited. The antibiotic will take care of the growth of the bacteria, but in a very toxic case antiserum may be required, which is certainly not available.

How well-equipped are the NIV, the National Institute of Communicable Diseases (NICD) and the Defence Research & Development Organisation (DRDO) to respond to an emergency situation and where does the respective expertise lie?

I cannot speak of other centres. During my tenure at the NIV, I tried to develop a microbial containment complex, a diagnostic laboratory with facilities for the preparation of diagnostic reagents, serum banking facilities and so on. All efforts were stalled by the high and mighty in New Delhi. At present, to the best of my knowledge, the capability is very limited.

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