It is indeed threatening & serious to comprehend the recent outbreak of ‘ Avian influenza’ or “bird flu” in the S-E Asian countries, which sent an alarm across the country particularly, the animal husbandry and the poultry farmers, and the general public. In general, the disease is possibly imminent and inevitable as this is found to be pandemic (world wide) and it can occur ill any part of the world. Our State has already witnessed the outbreak of Swine Fever and threats of Japanese -B- Encephalitis. The masses griped ‘by fear that bird flu might strike our state as we Nagas have close proximity with all domestic /wild birds or animals.
First of all, we need to know what is ‘actually ‘Avian influenza’ or ‘Bird Flu’? “Avian” indicates all the birds’. “Influenza” or “flu” is a synonym which indicates respiratory tract infections causing fever, body aches, moist coughing, pneumonia etc. Therefore, this is particularly a disease of the birds with high morbidity and mortality. Human happens to contact the disease through infected carrier birds/animals/human and inanimate objects. It is very important to note that the disease has caused an immense loss from the economic point of view, may be billions of dollar or more. Currently, nothing can be done to bring remedy to this pandemic disease though some drugs and anti flu vaccine has helped. It will be very expensive even to treat one chicken or other animals infected, and who knows a cheap vaccine may be available soon in the market.
Avian influenza or bird flu is caused by an RNA virus (orthomyxoviridiae) of the genus influenza virus. Influenza virus is again classified into 3 categories - Type A, type B and Type C. Type A and type B are more virulent. Basically, Type C causes influenza in humans and pigs. Avian influenza or bird flu is caused by Type A and one need not panic as the disease was identified more than 100 years ago in Italy. There are at present 15 avian influenza virus sub types viz-H7N7, H7Nl, H9N2, H5N2, H5Nl etc of which H5Nl is high1y pathogenic (dangerous at present) and this was detected in Hong Kong Feb. 2003, Netherlands and Republic of Korea Dec 2003, and Vietnam Jan 2004. It first became pandemic (world wide) during 1918- 19 by the name “Spanish flu”. China experienced it in 1957 and then, Hong Kong during 1968. The USA reported it in 1983 -84, Mexico in 1992 and in Italy during 1999-01.
The uphill task in combating this disease is a matter of great concern for one and all: it’s susceptibility to many domestic /wild animals and birds by their different sub types/ serotypes; unpredictability of the virus to change it’s pathogenicity from low to high; Evolvement of new strain (pathogenic strains) from their viral property of merging and re-assortment of genetic materials from different species known as “Antigenic shifting” producing a different strain unlike the parent viruses. This, however, is an event which is suppose to occur anywhere in the world, perhaps only once in 11 years. The Avian strain and mammalian strain are both susceptible to pigs, and Pigs can serve as “mixing vessels” resulting in the emergence of a novel serotype. Human themselves can serve as, “mixing vessels,” as they have close proximity to poultry and pigs. Most influenza virus experts agree the prompt culling (destruction) of entire Hong Kong poultry population in 1997 during a clinical trial with H5NI strain in human, which probably, averted a pandemic outbreak.
Several measures can help minimize the global public health risk. An immediate priority is to halt further spread of epidemics in poultry population, quarantining or destruction of potentially exposed flock, no contacts with migratory waterfowls (ducks) dead or alive as they are the main mechanical carrier although most resistant to infection, immediate report to the nearest veterinary doctors for any mysterious death of domestic /wild birds or animals, live birds markets should be viewed seriously, proper hygienic and sanitary measures undertaken in the farms like disinfections of farm equipments, beddings, cages, clothes and vehicles.
Moreover, bird’s dropping be it from wild or domestic should be “Properly disposed. Lastly, face masks and hand gloves are a must for persons at high risk of exposure.
Dr. T. Rongsenwati Ao
Animal Health Centre
Opp. Don Bosco School
Dimapur, Nagaland
