The Tribune, Chandigarh, India

Rabies phobia: the facts one must know
C.B. Singh

Rabies is primarily a disease of animals. In the absence of clear and precise information, panic is created following a dog’s bite. Many times the victim is put to expensive treatment and the pet is sacrificed unnecessarily. The physician must know some fundamental veterinary aspects of this disease. It is wrong to presume that lick or bite of every dog will cause rabies. The dog in question must be evaluated carefully in consultation with a canine veterinarian before deciding its fate and treatment regime for the victim, who could be a dog or a man.

Rabies, a totally fatal disease, was known as early as 2300 B.C. The word “rabies” is from the Latin word “rabere” — to rave — indicating the deranged mental state of the patients and the Sanskrit “rabhas”, which means to do violence. Hydrophobia and lyssa are the names for the same dreaded disease which we have no hope of eradicating in the foreseeable future in India. Hydrophobia means the fear of water which is one of the major signs of the disease in humans. The name “Hydrophobia” is given only to rabies in humans, and not in animals. A rabid dog can drink water and even swim. Lyssa — the Greek word for frenzy — denotes convulsions due to brain fever induced by a virus.

Only a handful of countries protected by the natural barrier of sea around them or their island location are free of rabies. Britain is one of them, free of rabies for the last 50 years because of its strict quarantine regulations and the geological location. Although the disease is usually fatal once the clinical sign appear, recovery has been reported in several animals and man with timely treatment. The first human victim of active rabies was saved by the famous French scientist Louis Pasteur on July 6, 1885, with the help of vaccine developed by him. Although the attempts to find cure for rabies are still elusive, the availability of state of the art anti rabies immunisation in conjunction with anti rabic serum and human rabies immunoglobulins have saved many lives.

Different animal species predominate in different parts of the world in maintaining and transmitting rabies. In India and the rest of Asia, the dog rabies predominates. Most warm-blooded animals from a mouse to an elephant may contract rabies. But some species which are normally “itters” like dogs, jackals and wolves are more prone to pass on the disease to others. Cattle, pigs, horses, mules, donkeys, cats, rabbits, rats, mongoose, foxes, skunks, racoons, squirrels and very rarely the carnivoral birds, including poultry, are other reported hosts.

Rabies is a viral disease and belong to the rhabdo virus group visible only under electronic microscope. The virus lives only in the nerve tissue and saliva of the infected animals. The incubation period of the rabies virus is 7 - 14 days and very rarely 21 - 90 days in dogs. After exposure the disease progresses rapidly, and after the initial phase of three-four days death is certain within 10 days of the first sign. That is why the 10-day observation period (of the dog in question) is recommended by the WHO. The virus passes onto the saliva of man or animal only at the end of the incubation period.

Rabies is transmitted to human beings and animals in the following manner: (1) Bite or a lick on a cut skin by a rabid animal. (2) Through mucous membranes of the mouth and eyes. (3) Aerosol transmission to man has also been reported, though rarely, in the laboratory and vampire bat-infested caves in Mexico, Central and South America and parts of the Caribbean. In India, the dog bite remains the primary source of transmission.

Rabies cannot be transmitted unless bitten by a rabid animal via its saliva rich in the virus. The fate of the disease process is decided by the quantum of the virus in the saliva at the time of bite and the immune status of the victim.

The rabies virus has an unusually different pattern as compared to other viral diseases where the defence mechanism of the victim’s body goes into action at once. But rabies spreads through the neural pathways without stimulating the defence mechanisms of the host. It has a longer incubation period comparatively, varying from case to case. Following a deep bite by a rabid animal the initial multiplication of the virus (mostly slowly) occurs at the wound site and hence gives time for post-exposure immunisation. The virus then starts travelling through the nerve endings and via the nerve cells to become concentrated in the area of brain where the cells are destroyed by the multiplying virus. This part of the brain runs across the middle of the head from side to side and controls sensations of the tongue, the face and the neck, and movements of the legs, the body and the arms as well as speech.

The obvious signs and symptoms occur when a sufficient number of brain cells have been damaged. First the rabies virus travels along the nerves from the site of the wound towards the brain and then back (at the speed rate of about 3-4 mm/hr.) towards the target organs of the body, particularly the salivary glands which then secrete virus laden saliva — the source of infection in a bite wound. In the brain, where cells are destroyed, small black oval or round clots are formed — known as negri bodies — and can be seen under, the microscope to confirm the disease. The brain cells once damaged by the rabies virus can never be regenerated, and the progress of the disease cannot be stopped. The only help is a long incubation period of 7 - 10 days which allows the necessary steps to be taken to prevent the disease development after a person/animal has been exposed to rabies.

Fortunately, the virus is easily killed by sunlight, heat and standard disinfectants. After thorough cleaning of the premises where a rabid animal has been living there is no fear of the virus. The virus dies in dried saliva within a few hours, again fortunately. The virus dies in dried saliva within a few hours, again fortunately. The virus may be shed in urine, feces and milk and may persist in carcasses for 24 hours or more, depending on the climate.

The writer, a veterinarian, is General Secretary, Small Animal Clinicians Association, Chandigarh.

Crooked teeth are injurious to health!
Aarti Mishra

Not many people can smile with confidence if they have crooked, protruding or irregular teeth. In dentistry, malocclusion means a condition in which teeth are protruded, crowded, rotated or irregular. It may also be characterised by facial asymmetry due to an abnormal relationship of the lower jaw with the upper one.

Beautifully aligned teeth and facial symmetry are assets that everyone does not possess. According to Dr T.M. Graber, Chairman, Orthodontics University of Chicago, malocclusion is a close runner-up to dental caries (cavities) in incidence throughout the world.

Hereditary factors, pressure habits like thumb-sucking and premature loss of milk teeth are some of the factors that can lead to malocclusion.

Crooked teeth and abnormal jaw relationships have an adverse effect on the health and well-being of a person as described below. They should, therefore, be corrected as soon as possible.

Teeth look aesthetically pleasing only when they are in proper alignment. Facial disharmony and protruding crooked or irregular teeth spoil facial aesthetics. They also undermine a person’s confidence because there is an important relationship between aesthetics, self-image and confidence.

Don’t you feel jubilant and “on top of the world” when you know that you are looking your best? Aesthetics or the desire to look good is the number one reason for which people seek orthodontic treatment.

Children with protruding teeth are often teased by playmates and called names like Bunny Rabbit. Kids with irregular teeth that are out of place are also made an object of ridicule. Their playmates pass uncomplimentary or even humiliating remarks about them.

Most teenagers are extremely concerned if their teeth are abnormal. Mal-aligned teeth, at this stage in life, have an unfavourable effect on appearance, confidence and social life. Reasons of psychological well-being are as important as those of aesthetics.

Protruding teeth are most vulnerable to accidents and fractures from falls, drinking fountain or another child’s head. They are most likely to get injured during sporting activities like cricket, hockey, bike riding, skating, football, basketball and martial arts.

According to Dr Graber, many speech authorities have recognised that dental malocclusions play a role in speech pathology. Here are a few examples of how speech gets affected by dental malocclusion:

(a) When the pre-maxilla (the front portion of the upper jaw) is protruding, the normal production of consonants like “m”, “b” and “p” becomes difficult.

(b) When there is an anterior open bite (a type malocclusion in which upper and lower front teeth fail to meet) the tongue position becomes abnormal and a lisp-like sound is produced.

Speech-defects hinder proper communication. They are a handicap at your work place as well as in your social circle. Correction of the malocclusion often eliminates the speech defects.

When teeth are irregular, oral hygiene is more difficult to perform, especially for children. The food that lodges in between the teeth leads to tooth decay (cavities) and gum disease.

The effect of dental malocclusion on the gums is so important that malocclusions are frequently corrected in adults in the USA. If this is not done, a premature loss of teeth in adults becomes inevitable.

Orthodontics is the science which corrects and prevents dental malocclusions. It is the oldest speciality of dentistry and is a boon for people who unfortunately have mal-aligned teeth. By bringing irregular teeth in proper alignment, an orthodontist improves aesthetics, enhances self-esteem and confidence of a person and saves him from fractured teeth and the two most common dental problems called caries and gum disease.

The writer, a Ludhiana-based dental surgeon, is a member of the American Dental Association.

INFO CAPSULE

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Researchers from Johns Hopkins School of Medicine in Baltimore, Maryland, told an international conference on Monday that patients with high blood pressure, diabetes or who have had a previous stroke are more likely to experience the ill effects of the surgery.

"There appears to be a sub-population of patients undergoing coronary bypass surgery, with risk factors for stroke, cognitive decline and long-term cognitive changes", Dr Guy McKhann told a meeting on Alzheimer's disease.

Dr McKhann and his team studied the medical histories of 3,300 patients who had coronary bypass surgery between 1997 and 2001. Nearly 3 per cent of the patients suffered a stroke and 6.8 per cent were confused or had short-term memory problems after the surgery. Reuters

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While scientists have tried for years to extract Mother Nature’s cures from the world's 250,000 or so plant species, there has been little research into the proteins, enzymes and molecules produced by the four million plus insect species.

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Minimum invasive surgery for haemorrhoids

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Dr Hardyal Chauhan, Deputy Medical Superintendent, said that the pain and blood loss was insigficant as compared to the conventional method and the patient had to be hospitalised for five to seven days.

The team of surgeons was headed by Prof R.K. Sharma and comprised Dr R.K. Abbey and Prof J.R. Thakur. They performed the operation on a 62-year-old resident of Bamithi village in Chopal. TNS