Blood Groups, STIs, and Eruptive Diseases
Blood groups: A, B, AB, and O. In group O, no A or B antigens are present on the red blood cells, and the plasma contains both anti-A and anti-B antibodies. In group A, antigen A is found on red blood cells, and the plasma contains anti-B antibodies. In group B, antigen B is found on red blood cells, and the plasma contains anti-A antibodies. This explains transfusion reactions: group O blood can be donated to all groups but can only receive from group O (universal donor). Group A can donate to A and AB and receive from A and O. Group B can donate to B and AB and receive from B and O. Group AB can donate to AB and receive from all groups (universal recipient).
Syphilis is caused by bacteria and transmitted through direct contact with a syphilitic ulcer, typically found on the genitals, vagina, anus, rectum, lips, or mouth. Many individuals show no symptoms for years but risk complications in later stages without treatment. Primary syphilis symptoms include painless sores and swollen lymph nodes. Secondary syphilis may cause fever, fatigue, and pain. Tertiary syphilis affects the heart, brain, and nervous system. Treatment involves antibiotics (penicillin) and follow-up blood tests.
Gonorrhea is caused by bacteria that thrive in warm, moist areas of the reproductive tract, mouth, throat, eyes, and anus. It spreads through contact with the penis, vagina, mouth, or anus. Symptoms appear 2 to 5 days after infection, but men may not show symptoms for up to a month. Symptoms include burning urination, and white, yellow, or green penile discharge. Men may experience swollen or painful testicles. Women may experience painful urination, increased vaginal discharge, and vaginal bleeding between periods. Rectal infection symptoms in both sexes include discharge, itching, pain, bleeding, and painful defecation.
AIDS (Acquired Immune Deficiency Syndrome) is an infectious disease caused by the Human Immunodeficiency Virus (HIV). HIV uniquely attacks cells crucial to the immune system. Initially, HIV may remain dormant in lymphocytes, but it eventually destroys cells, weakening the immune system. HIV infection doesn’t automatically mean someone has AIDS, but it can transmit the infection. Transmission occurs through:
– Blood: Sharing needles, syringes, or sharp objects; during pregnancy, childbirth, or uncontrolled blood transfusions.
– Sexual transmission: Homosexual or heterosexual intercourse transmits HIV through microscopic lesions or wounds.
– Perinatal transmission: An HIV-positive mother can transmit the infection to her baby during pregnancy, childbirth, or breastfeeding.
Main symptoms: Unexplained exhaustion, prolonged swollen glands, fever (lasting over 10 days), colds, excessive sweating (especially at night), mouth sores, swollen and painful gums, sore throat, cough, shortness of breath, tumors, unintentional weight loss, general malaise, and headache.
Eruptive diseases:
Chickenpox: Agent: Varicella-zoster virus (herpesvirus). Symptoms: 14-18 day incubation, mild fever, rash starting on the trunk, then spreading to the face, neck, limbs, and scalp. Contagion: Direct.
Measles: Agent: Paramyxovirus. Symptoms: 10-12 day incubation, pre-eruptive photophobia, mouth staining, and a skin rash. Contagion: Direct.
Rubella: Agent: Rubella virus. Symptoms: 1-2 week incubation, swollen neck glands, colds, followed by a rash. Contagion: Most contagious during the rash.
Mumps: Agent: Paramyxoviridae virus. Symptoms: 18-21 day incubation, malaise, sore throat, dry mouth, and swollen salivary glands. Contagion: Direct, confers lifelong immunity.
Sixth Disease (Exanthema subitum): Symptoms: 7-20 day incubation, high fever (2-3 days), tonsillitis, then rash appearing after fever subsides (lasting 2 days).
Scarlet Fever: Agent: Streptococcus. Symptoms: Begins with sore throat, followed by a red rash, high fever, headache, stomach ache, and vomiting. Contagion: Direct.