Critical Illness policy is a fixed benefit plan that provides coverage when the policyholder is diagnosed with any of the life-threatening critical illnesses mentioned in the policy documents. The policyholder receives the entire sum insured irrespective of the actual expense for the treatment or if the insured is hospitalized or not.

The list of critical illnesses covered will vary from company to company and policy to policy. Here are some of the major critical illnesses that are covered in most of the policies:

Myocardial Infarction (First Heart Attack): 
The first occurrence of myocardial infarction means the death of a portion of the heart muscle as a result of inadequate blood supply to the relevant area. 

Coronary artery by-pass grafts (CABG) (with surgery to divide the breastbone):
The actual undergoing of open chest surgery for the correction of one or more coronary arteries, which is/are narrowed or blocked, by CABG. The diagnosis must be supported by coronary angiography and the realization of surgery has to be confirmed by a specialist medical practitioner.

Stroke: 
Any cerebrovascular incident producing permanent neurological sequelae. This includes infarction of brain tissue, thrombosis in an intracranial vessel, hemorrhage and embolization from an extracranial source. Diagnosis has to be confirmed by a specialist medical practitioner and evidenced by typical clinical symptoms as well as typical findings in CT scan or MRI of the brain. Evidence of permanent neurological deficit lasting for at least 3 months has to be produced.

Cancer (of Specified Severity): 
A malignant tumor characterized by the uncontrolled growth & spread of malignant cells with invasion & destruction of normal tissues. This diagnosis must be supported by histological evidence of malignancy & confirmed by a pathologist. The term cancer includes leukemia, lymphoma & sarcoma.

Major Organ Transplant: 
The actual undergoing of a transplant of one of the following human organs: heart, lung, liver, kidney, pancreas that resulted from an irreversible end-stage failure of the relevant organ, or human bone marrow using hematopoietic stem cells 

Multiple Sclerosis:
The definite occurrence of multiple sclerosis with the diagnosis support by all of the following: 

• Investigations including typical MRI and CSF findings, which unequivocally confirm the diagnosis to be multiple sclerosis 
• there must be current clinical impairment of motor or sensory function, which must have persisted for a continuous period of at least 6 months, and  
• Well documented clinical history of exacerbations and remissions of said symptoms or neurological deficits with at least two clinically documented episodes at least one month apart

Paralysis: 
Total and irreversible loss of use of two or more limbs as a result of injury or disease of the brain or spinal cord. A specialist medical practitioner must be of the opinion that the paralysis will be permanent with no hope of recovery and must be present for more than three months.

Alzheimer's Disease:
It is a neurological disorder in which the death of the brain cells may cause memory loss, confusion, communication problem, and cognitive decline. These conditions must be medically documented for at least 90 days. The following needs to be diagnosed before age 60 years as confirmed by a medical practitioner.

Total Blindness: 
Total, permanent and irreversible loss of all sight in both eyes as a result of sickness or accident. Diagnosis has to be confirmed by a specialist (best by an ophthalmologist) and evidenced by specific test results.

Total Loss of Speech: 
Total loss of the ability to speak for a continuous period of 6 months due to a tumor or serious injury which has led to the removal of vocal cords.

Progressive Scleroderma: 
Scleroderma is a chronic hardening and contraction of the skin and connective tissue, either locally or throughout the body.

Aorta Graft Surgery: 
The aorta is the body's main artery carrying blood from the heart. An aorta graft surgery means, where a part of the aorta is removed and replaced with a graft/valve. This procedure is required to correct a weakening or bulging in the artery.

Apallic Syndrome:
Formerly called Apallic syndrome or Persistent Vegetative State (PVS). Unresponsive Wakefulness Syndrome (UWS) is very serious brain damage when cortical parts of the brain are disconnected from the brainstem. The patient has severe brain damage leading to coma but has progressed to a stage of partial arousal, rather than true awareness.

Aplastic Anemia: 
Aplastic Anemia is a condition in which the body stops producing enough new blood cells. It develops as a result of bone marrow damage.

Bacterial Meningitis: 
Bacterial meningitis is the most serious type of meningitis. It can lead to death or permanent disability. Meningitis is inflammation of the brain and the spinal cord membranes, typically caused by an infection that can cause the tissues around the brain to swell.

Benign Tumor in the Brain (resulting in permanent neurological symptoms):
A benign tumor is a non-cancerous abnormal growth of tissue that can increase in size and cause pressure in the brain. Some symptoms are headaches, seizures, and blurred vision.

Brain surgery: 
The term “brain surgery” refers to various medical procedures that involve repairing structural problems in the brain. There are numerous types of brain surgery. The type used is based on the area of the brain and the condition being treated.

Cardiomyopathy: 
Cardiomyopathy is a disease of the heart muscle that makes it harder for your heart to pump blood to the rest of your body. Cardiomyopathy can lead to heart failure. Symptoms of Cardiomyopathy are shortness of breath, fainting, and palpitations.

Coma (Up to the specified severity): 
A coma is a state of unconsciousness from which the patient cannot be aroused and has no control over bodily functions. It may be caused due to illness, stroke, infection, very low blood sugar or serious accident.

Creutzfeldt-Jakob disease (CJD): 
It is a rare, degenerative brain disorder that leads to dementia and death. It may be present without symptoms for many years. Once the symptoms appear they may include failing memory, problems with vision, immobility, loss of speech and coma in advanced stages.

Deafness: 
Deafness, hearing impairment, or hearing loss refers to the partial or total inability to hear sounds. 

Encephalitis: 
It is an inflammation of brain tissues which is caused due to infection. Symptoms might include a severe headache, nausea, vomiting, convulsions, and personality changes, problems with speech/hearing, confusion, and disorientation.

End-stage Liver Diseases (of specified severity):
It means liver failure at an advanced stage. A severely advanced liver disease resulting in cirrhosis i.e. late stage of fibrosis (scarring) of the liver caused by many forms of liver diseases and conditions.

End-stage Lung Diseases: 
It means advanced lung failure when breathing is severely affected and regular oxygen therapy is required.

Goodpasture Syndrome (GPS): 
It is an autoimmune disease in which antibodies attack the lungs and kidneys, leading to permanent lung and kidney damage. It also leads to bleeding from the lung and kidney.

Kidney Failure Requiring Regular Dialysis:
End-stage renal diseases presenting as a chronic irreversible failure of both kidneys to function. In such situations, regular dialysis may be required to do the filtering or a transplant.

Major Burns: 
These are third-degree burns that cover at least 20% of the surface of the insured's body.

Major Head Trauma: 
A physical head injury causing significant permanent functional impairment lasting for a minimum period of 3 months from the date of trauma or injury.

Motor Neuron Disease with Permanent Symptoms:
Motor neuron diseases are a group of conditions that cause the nerves in the spine and brain to lose function over time. This leads to gradual weakening and wasting of the muscles, usually starting with the arms and legs. It may cause difficulty in walking or holding objects.

Multiple System Atrophy (MSA):
It is a progressive disease of the nervous system. It may lead to permanent clinical impairment. Symptoms include - muscle weakness, swallowing difficulties, slow movement, autonomic dysfunction,  postural instability, and muscle rigidity.

Open Heart Replacement or Repair of Heart Valve:
Open-heart surgery is used to repair or replace heart valves. Meaning, that a large incision is made in the chest and the heart stopped for a time so that the surgeon can replace or repair the valve(s).

Pneumonectomy:
it is a surgical procedure to remove a lung infected to disease or traumatic injury.

Primary Parkinsonism Disease (Parkinson's Disease): 
Parkinson's disease is a condition in which part of the brain (central nervous system) progressively damages for years. The main symptoms are involuntary shaking of particular parts of the body, slow movement, stiff and inflexible muscles.

Primary Pulmonary Arterial Hypertension:
It is a type of high blood pressure that affects arteries in the lungs and the heart.

Progressive Supranuclear Palsy (PSP):
It is a brain disease that develops slowly, which progresses to seriously affect vision and movement.

Systemic Lupus Erythematosus (SLE):
Also know as 'lupus' is an inflammatory disease caused when the immune system attacks its own tissues i.e. the body creates antibodies, which work against it.

Total Loss of Speech: 
The total loss of the ability to speak. It's often caused when the vocal cords need to be removed because of a tumor or a serious injury.