RABIES VIRUS (fatality rate 99%) 
(fatality rate =death rate)
Rabies virus is a neurotropic virus which causes rabies in humans and animals. Rabies is a disease which is transmitted through saliva of affected animals that is through  bites. Eg: dog bites.
Rabies is the most deadliest virus ,once clinical symptoms appear rabies is Virtually 100% fatal.
Once rabies enter the human body,it causes inflammation of the brain and spinal cord .once the virus reaches the spinal cord and brain it becomes more fatal. Normally when  heard of rabies what first comes to our mind is dog bite but an interesting fact is that bats are responsible for most of the deaths due to rabies. Specialist whom should be seen by patients after rabies symptoms are emergency medicine doctor and infectious disease doctor. 
TRANSMISSION 
Transmission of rabies virus contains 8 steps.

1. First step is the virus inoculation.
   virus enters a human body through animal bites.
    
2. After entering human body starts replication in muscles.
3. virion enters the peripheral nervous system. 
4. virion then ascends through the sensory fibres(passive ascent)
5. Replication of virion in dorsal ganglion.
6. Rapid ascent of virus throughout spinal cord. 
7. Infection of brain stem ,cerebrum and other brain structures through the spread of virus from spinal cord.
8. Once the virus reaches the ultimate brain structures then there will be descending infections throughout the nervous system that is to eye, salivary glands, skin and other organs. 
   SYMPTOMS 
   Symptoms during incubation period:
   • Fever
   • Headache 
   • Tingling or burning sensation at the site of bite or scratch 
   Symptoms during prodromal period
   • Fatigue, malaise
   • Sore throat 
   • Nausea, vomiting, diarrhea 
   Initial symptoms 
   • Headache 
   • Fever
   • Fatigue 
   • Tingling at site of bite
   Rabies specific symptoms 
   • Hallucinations 
   • Excessive salivation (drooling) 
   • Light sensitivity 
   • Hydrophobia
   • Insomnia
   • Aggression 
   DIAGNOSIS 
   skin biopsy 
   Blood tests 
   Lumbar puncture 
   Head MRI
   CT scan 
   Saliva test by virus isolation 
   RT-PCR
   DFA Test (direct fluorescent antibody test) 
   TREATMENT 
   When a rabies infection is laid out, there's no powerful treatment. However few individuals have survived rabies, the sickness normally causes demise. Assuming you've been bitten by an animal that is known to have rabies, you'll get a progression of shots to keep the rabies infection from contaminating you. Rabies shots include: 
   ● An effective shot (rabies immune globulin) to keep the infection from contaminating . This is given in the event that you haven't had the rabies immunization. This infusion is given close to the region where the animal bite is. 
   ● A series of rabies vaccinations can help the body learn to identify and fight the antigens of rabies virus. Rabies vaccinations are given as injections in the arm. If the person hasn't previously had the rabies vaccines, the person will receive four injections over 14 days. If the person had the rabies vaccine, the person will have two injections over the first three days.