This is the most dreaded disease of modern times. The disorder is characterised by a reduction in the number of helper T-cells that activate other lymphocytes, which are responsible for the body immunity system.
So in this disease, the destruction of lymphocytes makes the man highly susceptible to different diseases.
AIDS was first recognised in USA in 1981. It occurs due to Human immune deficiency virus (HIV) (Fig. 6(B).4). Most scientists believe that – HIV probably first appeared in man between 40 to 100 years ago.
Early evidence for HIV comes from studies of human blood stored, in Zaire in 1959.
Transmission of AIDS:
The HIV was transmitted mainly by the following means:
(a) The contaminated needle or razor blades transmit HIV The intravenous drug abusers are the main victims.
(b) HIV transmission occurs by transfusion of infected blood.
(c) It is primarily a sexually transmitted disease, which is transmitted through homosexuals and unrestricted sexual behaviour.
(d) The foetus gets infected from the infected mother through placenta.
Symptoms of AIDS:
HIV infection can be divided into three stages:
1. Asymptomatic Carrier:
Only 1% -2% of newly infected persons show symptoms like fever, chills, aches, swollen lymph glands and itchy rash. These symptoms disappear for about 9-10 months, but the patient remains highly infectious. The HIV test shows positive test.
2. AID Related Complex (ARC):
The most common symptom of ARC is swollen lymph glands in the neck, armpits or groin that persists for nearly three months. It is accompanied by persistent and recurrent fever, cough, cold, flu and diarrhea. Sometimes nervous impairment including loss of memory, inability to think clearly, loss of judgement and depression etc. The appearance of non-life threatening and recurrent infections is a signal for development of full blown AIDS.
3. Full-Blown AIDS:
The full blown AIDS shows severe weight loss due to persistent diarrhea and some opportunistic infections. The destruction of immune system gives opportunity to some diseases. These are called opportunistic diseases.
Some of these diseases are:
a) Pneumonia (Pneumo cystis carinii):
This type of pneumonia only occurs in AIDS patients.
b) Toxoplasmic encephalitis:
It causes loss of brain cells, weakness and seizures in patients suffering from full blown AIDS.
c) Myobacterium avium:
This is an infection of bone marrow. It causes decrease in RBC, WBC and platelets.
d) Kaposi’s sarcoma:
It is a cancer type disease which occurs in blood vessels. It causes reddish purple, coin-size spots and lesion on the skin.
The infectious secretions of an AIDS patient are semen, cervical secretions, blood and blood products.
The spread of this disease can be prevented by:
(i) Avoiding sexual intercourse i.e. both vaginal and anal.
(ii) Avoiding use of needles, razor blades which are used by the patient.
(iii) Avoiding the syringe used by drug abusers.
(iv) Not allowing the infected mother to give birth a child.
(v) Not allowing the young child to feed on breast milk of infected mother.
It is known as hugging social kissing, shaking hands, coughing, sneezing etc., do not spread this disease.
Some drugs like Zidovudine and dideoxy inosine (DDI) prevents HIV reproduction in the cells. Jonas Salk (who developed Polio vaccines) have developed HIV-1 vaccines which are found to be effective against experimental HIV-1 infection in chimpanzees. Though there is strong expectation that vaccines for AIDS will develop soon, yet this disease is now considered as incurable one. Its transmission shows rapidity. It can only be controlled by prevention to save the mankind from destruction.