Introduction
Infectious diseases are illnesses caused by microorganisms such as bacteria, viruses, fungi and parasites. These organisms enter the human body, multiply and produce symptoms. Many infectious diseases spread through contaminated food, water, insects, air or direct contact between people. Early diagnosis and proper treatment are essential to prevent complications.
1. Typhoid Fever
Typhoid is caused by Salmonella typhi. It spreads mainly through contaminated food and water.
Symptoms
- High fever
- Headache and weakness
- Loss of appetite
- Abdominal discomfort
Diagnosis
Widal test, blood culture.
Prevention
Safe drinking water, proper sanitation and vaccination.
2. Tuberculosis (TB)
TB is a chronic infection caused by Mycobacterium tuberculosis. It usually affects the lungs but can involve other organs.
Symptoms
- Long-lasting cough
- Chest pain
- Night sweats and fever
- Weight loss
Diagnosis
Chest X-ray, sputum test, Mantoux test.
Prevention
BCG vaccine and early detection.
3. Malaria
Malaria is caused by Plasmodium parasites and transmitted by the bite of an infected female Anopheles mosquito.
Symptoms
- Fever with chills
- Body pain
- Weakness
Diagnosis
Blood smear, rapid diagnostic tests.
Prevention
Use of mosquito nets, repellents and control of mosquito breeding.
4. Cholera
Cholera is an acute diarrhoeal disease caused by Vibrio cholerae. It spreads through contaminated water and food.
Symptoms
- Profuse watery diarrhoea (“rice water stool”)
- Vomiting
- Severe dehydration
Diagnosis
Stool culture and rapid tests.
Prevention
Safe drinking water and ORS for dehydration.
5. Hepatitis
Hepatitis refers to inflammation of the liver. Common types include A, B, C, D and E.
Route of Spread
- A & E: Contaminated food and water
- B, C & D: Blood, unsafe injections, sexual contact
Symptoms
- Yellowish skin and eyes (jaundice)
- Fatigue
- Abdominal discomfort
Prevention
Vaccines for hepatitis A and B, safe injection practices and hygiene.
6. Meningitis
Meningitis is infection of the protective membranes of the brain and spinal cord. It may be caused by bacteria, viruses or fungi.
Symptoms
- High fever
- Severe headache
- Neck stiffness
- Vomiting
Diagnosis
CSF examination (lumbar puncture).
Prevention
Vaccination and early treatment.
7. Syphilis
Syphilis is a sexually transmitted disease caused by the bacterium Treponema pallidum.
Symptoms
- Painless sore (primary stage)
- Rashes on skin (secondary stage)
- Neurological and cardiac damage (late stage)
Diagnosis
VDRL, RPR, Treponemal tests.
Prevention
Safe sex practices and early treatment.
8. Gonorrhea
Gonorrhea is caused by Neisseria gonorrhoeae and spreads mainly through sexual contact.
Symptoms
- Burning sensation during urination
- Pus discharge
- Pelvic pain in women
Diagnosis
Gram staining and culture.
Prevention
Safe sexual practices and timely treatment.
9. HIV / AIDS
HIV (Human Immunodeficiency Virus) attacks the immune system and gradually destroys CD4 cells, leading to AIDS.
Transmission
- Unprotected sexual contact
- Contaminated needles
- Blood transfusion
- Mother-to-child transmission
Symptoms
- Fever and weight loss
- Recurrent infections
- Weak immunity
Diagnosis
ELISA, Western blot and PCR.
Prevention
Safe sex, clean needles, ART therapy and screening of blood.
Detailed Notes:
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