Rabies is an acute,almost fatal infectious disease of animals mainly in canidae tribe from which man is secondarily infected.After 15 days of incubation period the infected dog shows symptoms in one of the two forms i.e dump or paralytic form and furious form.Furious canine rabies causes maximum cases of the diseases in man.Stray dogs and pet dogs are the intermediate host of the disease to human beings and animals like cow,be-fellow,cat,sheep,etc.When the disease occur in man it is known as Hydrophobia, means fear of water.In man the disease is characterized by sudden onset with headache malaise and nervous symptoms of depression progressing to paralysis with spasms of muscles on attempt to drink,followed by delirium and convulsion and resulting to death from respiratory failure with in two days to a week.The difficulty to drink water is in patients only in human beings,and does not occur in dogs or other animals.
The organism causing this disease is a neurotropic filterable virus.The strain recovered from the stray rabid dog has been named as"the street virus".It is found normally in the hippocampus of the rabid dogs/animals brain and that of man dying of hydrophobia.Virus is present in the saliva one week before symptoms appear.The street virus loses its virulence and retains the antigenic properties when passaged a hundred times through the rabbit.This is used for preparation of antirabic vaccine and is named as"Virus fixe"
The temporary reservoir of infection is found in the canidae. Some of the members of these families harbour the virus with out suffering from the disease or death,and also excrete it in saliva at intervals
for long time.The Indian mongoose and the American Vampire bats are also found to harbor the virus.Some wild rodents also have been suspected of playing an intermediary role in the transmission of infection from animal to animal with in these tribes of canidae families and non-canidae families to the wild canidae tribe,with out themselves suffering from the disease.Therefore,these animals serve as permanent reservoir of infection in nature,migrating from this reservoir occur in wild canidae like,jackals,foxes,wolves and wild dogs in whom reservoir is found.Transmission of virus then occur
from wild canidae to domestic stray dogs,when meeting them on the out sides of town,near butcheries
and refuse disposal yards.In rural areas the wild canidae can meet the domestic stray dogs with in the areas of the villages.Domestic stray dogs thereafter transmit to pet dogs.
The canines suffer and die of the disease with in 10 days after the symptoms appear.For man the source of infection is from the rabid ,domestic,street,or pet dogs or cats.In rural areas wild dogs,foxes,jackals or wolves may attack human beings,during epizootics among st domestic dogs and cats.Infection is transmitted through bites coming out blood or licks on broken skin surface by the rabid dog.Infection doesnot occur with out some injury of epidermis or mucosa. Virus deposited at the site lastly reaches the central nervous system and the route and its travel up to brain is doubtful but the blood stream do not play a part;perineural lymphatics of the secondary nerves may be the route of travel.The average incubation period developing hydrophobia in man is 3 to 8 weeks,may vary from 10 to 90 or longer up to 6 months as per location of the bite and wound from head.The nearer the dog-bite to brain the shorter is the incubation period.In animals incubation period
is about 2 weeks.
The saliva of a rabid dog or fox is ineffective for a week to ten days,before symptoms appear,till death of the dog.but some times occurs only a time before the starting first symptoms of rabies appear. All warm blooded animals and mammals are susceptible.Man possess no natural immunity against the disease.Rabies has a distribution all over the wold.It was absent long time in some countries like New Zeal and, Australia,Hawaii and some pacific islands,and some other countries like U.K, Scandinavia were strict anti-rabies vigilance is observed.In Asia and Africa the disease is very common.In India more than 7000 cases of hydrophobia occur in every year.
Preventive measures against hydrophobia;Immediate first aid treatment of dog bite should be given on the spot.All bites from dogs and other animals should be regarded as dangerous and first aid treatment should be carried out immediately.
The wound should be suddenly cleaned and washed thoroughly with soap and water to reach the depths of pockets of the wounds with the help of a forcible jet of water and application of tincture
of iodine or 70 % of ethyl alcohol should be carried out with swab so as to reach the depths of wound.
In emergency 20 percent soap solution can be used for this purpose.Local application of 5 ml hyper immune antirabic serum around and underneath wound is an added helpful first aid if possible.Tetanus toxoid 0.5 ml given to all pre immunized persons.Antibiotic treatment may be needed to treat badly lacerated cases and subsequent infection.Normally sutures do not apply for 3 days.
A full course of antirabic vaccination is the only specific procedure which prevents hydrophobia.The
principle is to make an active immunity by giving daily injection by the modified inactivated rabies virus during the incubation period.Vaccination must be started and completed very early after the rabid dog bite.
Generally there is no danger of infection through unbroken skin,but the virus may have been present in the saliva of the dog up to 10 days before the onset of the symptoms,the patient has to decide for himself whether there is any possibility of the dog having licked on the broken skin during that period.The medical attendant should not be expected to decide this for him.If the patient is with considerable doubt in such cases antirabic treatment is generally given to be on the safe side.
In some cases, antirabic treatment is not necessary.1.Drinking of milk from rabid animals.2.If the biting animal remains healthy and alive for a minimum period of 10 days after the bite.3.A bite through clothes with out tearing, when the skin not broken,even though the bruise co lour may be present.4.Handling of clothes or materials contaminated by the rabid animal or a patient of hydrophobia.5.Handling of animals bitten by rabid animals provided the skin of the individual is free from cuts,abrasions open injuries.6.Attendance on a case of hydrophobia,unless bitten by him.
Complication of antirabic treatment;Anaphylactic reaction may happen in sensitive persons.Non specific reaction may also occur, like,moderate local pain,redness and swelling,etc.mainly in obese patients.For these complaints local fomentation may apply.High fever,malaise,headache,pain and stiffness in neck and back or limbs may appear after 4th day due to allergic manifestations which is rare complication to antirabic vaccine treatment.In India the reported cases were one in fifteen thousand persons under vaccine treatment.This occurs between 9th and 15th day of treatment
more in males than in females.and among adults than in children.
Prevention and control of rabies in animals; It consists of mainly controlling the stray dog population,protection of pet dogs and cats and prevention of importation of disease from out side,if the country is already disease free, and personal protection against dog bite.Destroy or plan the growth of number of stray dogs in the country specially owner less dogs.All pet dogs to be registered
and use of metal badges on the collar,to identify from them stray dogs and owner less dogs.For promoting registration the local authorities should give free pre-exposure antirabic immunization and free treatment for other canine diseases.Ingress of wild canidae in habitations and their mixing with domestic dogs can be controlled making the slaughter houses,rubbish disposal yards,poultry farms and such other places attracting dogs,animal food and disposal of all such waste by burning.To promote caniculture, publicity campaign should be carried out,registration of pet dogs,their protection and destruction stray dogs.Education regarding the dangers of rabies,rabid dog bites and important of early vaccine treatment must be carried out.During an epizootic,restrain the movements of all dogs and observe them at least for 3 months.Dogs that have been bitten by rabid dog should be destroyed preferably.Dogs in contact with ,but not known to have been bitten by a rabid dog to be kept and given antirabic vaccine treatment and be observed for 6 months.Self protection from dog bites,as the bites are through clothes and likely to transmit disease,trousers and full sleeve shirts are more protective than other type of Indian clothing.Disinfect all places where a rabid animal has been confined and the carcase of a rabid animal must be buried with quick lime or cresol solution.Health laws of some countries do not permit any dog to import from any country.Some countries permit them to import after quarantining period of six months.Some countries with and others with out taking compulsory immunization as per their law permits.
Particulars of all dog bites and cases of hydrophobia to be warned all concerned regarding the presence of epizootic or endozootic in the area,and also report should be given to higher medical
authorities.All valuable animals should be given regular vaccination in endozootic areas.The mortality is 100 percent and no curative treatment is not available,patients should be admitted hospital and observed in a quiet room shaded light and all the forms disturbance must be avoided.Attendants must wear gloves,gown goggles.In case he comes to expose the risk of infection
by the bite of patient or contact with his saliva on broken skin,he must take correct course of treatment.Bedding and clothing used by patients or contacted by rabid dogs should be soaked in 5%
cresol solution or exposed to formalin mixed with potassium permanganate fumes for one day,then washed and dried in the sun for 24 hours.There being no other points presently with me,this has come
to an end.
pm kutty