Infections

Infections are the invasion and multiplication of pathogenic microorganisms in the body, which may cause local cellular injury or a systemic response. They can be caused by a wide range of pathogens, including bacteria, viruses, fungi, and parasites.

Infected eye

Surgical stiches - knee infection

Types of Infections

Infections are typically categorized based on the causative agent:

Viral infections

• Bacterial infections: Caused by bacteria, examples include tuberculosis, strep throat, and urinary tract infections.
• Viral infections: Caused by viruses, such as influenza, HIV/AIDS, and the common cold.
• Fungal infections: Arise from fungi, including candidiasis, ringworm, and athlete's foot.
• Parasitic infections: Result from parasites like malaria (from plasmodium species) or tapeworm infestations.
• Prion infections: Caused by prions, misfolded proteins that can lead to conditions like Creutzfeldt-Jakob disease.

Routes of Transmission

Streptcoccus Group G infection of tonsils

• Direct contact: Through skin-to-skin contact, bodily fluids, or respiratory droplets.
• Indirect contact: Through fomites, objects or materials likely to carry infection.
• Vector-borne: Via organisms such as mosquitoes, ticks, or fleas.
• Airborne: Through aerosol particles in the air.
• Foodborne or waterborne: Ingesting contaminated food or water.

Symptoms

While specific symptoms vary depending on the infection, common signs include fever, fatigue, muscle aches, and lymph node enlargement. Severe infections might lead to organ failure or systemic complications.

Diagnosis

• Culture tests: Growing the microorganisms from a sample.
• Blood tests: Checking for antibodies or presence of the causative agent.
• Imaging: Using X-rays, MRI, or other techniques to spot infection areas.
• Biopsy: Examining a small tissue sample.

Treatment

Treatment depends on the type of infection:

• Bacterial: Typically treated with antibiotics.
• Viral: May require antiviral medications, though many viral infections are self-limiting.
• Fungal: Antifungal medications.
• Parasitic: Antiparasitic drugs.

Prevention

• Vaccination
• Hand hygiene
• Safe food and water practices
• Proper personal protection against vectors

Complications

Untreated or severe infections can lead to:

• Sepsis: A life-threatening reaction to severe infections.
• Organ damage or failure.
• Chronic conditions: Some infections can cause long-term health issues, like hepatitis leading to liver cirrhosis.

Lists of infections

A

• Abscesses
• Acquired Immunodeficiency Syndrome see AIDS
• Adult Immunization see Immunization
• AIDS
  • AIDS and Infections
• Animal Diseases and Your Health
  • Animal Health see Animal Diseases and Your Health
• Anthrax
• Antibiotics
  • Antimicrobial Resistance see Antibiotics; Infectious Diseases
• Arachnoiditis see Meningitis
• Avian Influenza see Bird Flu
• Bacterial Infections

B

• Bird Flu
• Blood Poisoning see Sepsis
• Blood-Borne Pathogens see Infection Control
• Body Lice see Parasitic Diseases
• Botulinum Toxin see Botulism
• Botulism
• Bronchiolitis see Bronchitis; Respiratory Syncytial Virus Infections
• Bronchitis
• Bubonic Plague see Plague

C

• Candidiasis see Yeast Infections
• Cat Scratch Disease
• Cellulitis
• CFS see Chronic Fatigue Syndrome
• Clap see Gonorrhea
• CMV Infections see Cytomegalovirus Infections
• Cold, Common see Common Cold
• Common Cold
• Condylomata Acuminata see Genital Warts
• Coxsackievirus Infections see Viral Infections
• Crab Lice see Sexually Transmitted Diseases
• Cryptosporidiosis
• Cytomegalovirus Infections
• Chagas Disease
• Chickenpox
• Chlamydia Infections
• Chronic Bronchitis see Bronchitis
• Chronic Fatigue Syndrome

D-E

• Dengue
• Diphtheria
• E. Coli Infections
• Ebola Virus see Hemorrhagic Fevers
• EBV Infections see Infectious Mononucleosis
• Ehrlichiosis see Tick Bites
• Epstein-Barr Virus Infections see Infectious Mononucleosis
• Fever
• Fifth Disease
• Flu
• Fungal Infections
• Gastroenteritis

G-H

• Genital Herpes see Herpes Simplex
• Genital Warts
• German Measles see Rubella
• Germs and Hygiene
• Giardia Infections
• Glandular Fever see Infectious Mononucleosis
• Gonorrhea
• Grippe see Flu
• Handwashing see Germs and Hygiene
• Hantavirus Infections
• Head Lice
• Hemorrhagic Fevers
• Hepatitis
  • Hepatitis A
  • Hepatitis B
  • Hepatitis C
• Herpes Simplex
• Herpes Zoster see Shingles

I-J

• Histoplasmosis see Fungal Infections
• HIV see AIDS
• HPV
  • Human Immunodeficiency Virus see AIDS
  • Human Papillomavirus see HPV
• Immunization
• Impetigo
• Infantile Paralysis see Polio and Post-Polio Syndrome
• Infection Control
• Infections and Pregnancy
• Infections, Bacterial see Bacterial Infections
• Infections, Fungal see Fungal Infections
• Infections, Viral see Viral Infections
• Infectious Diseases
• Infectious Mononucleosis
• Influenza see Flu
• Itching
• Jet Lag see Traveler's Health
• Jock Itch see Tinea Infections

L-M

• Legionnaires' Disease
• Leishmaniasis
• Lice see Head Lice; Parasitic Diseases
• Listeria Infections
• Lyme Disease
• Malaria
• Measles
• Meningitis
• Monkeypox see Monkeypox Virus Infections
• Monkeypox Virus Infections
• Mononucleosis see Infectious Mononucleosis

N-P

• MRSA see Staphylococcal Infections
• Mumps
• Norwalk Virus Infections see Gastroenteritis
• Opportunistic Infections in AIDS see AIDS and Infections
• Paralysis, Infantile see Polio and Post-Polio Syndrome
• Parasitic Diseases
• Pelvic Inflammatory Disease
• Pertussis see Whooping Cough
• PID see Pelvic Inflammatory Disease
• Pinworms
• Plague
• Plantar Warts see Warts
• Pneumocystis Infections
• Pneumonia
• Polio and Post-Polio Syndrome

R-S

• Post-herpetic Neuralgia see Shingles
• Pregnancy, Infections in see Infections and Pregnancy
• Q Fever see Bacterial Infections
• Rabies
• Respiratory Syncytial Virus Infections
• Ringworm see Tinea Infections
• Rocky Mountain Spotted Fever see Tick Bites
• Roseola see Viral Infections
• Rotavirus Infections
• RSV Infections see Respiratory Syncytial Virus Infections
• Rubella
• Rubeola see Measles
• Salmonella Infections
• SARS see Severe Acute Respiratory Syndrome
• Scabies
• Scarlet Fever see Streptococcal Infections
• Sepsis
• Septic Shock see Sepsis
• Septicemia see Sepsis
• Severe Acute Respiratory Syndrome
• Sexually Transmitted Diseases
• Shingles
• Sinusitis
• Smallpox

S-T

• South American Trypanosomiasis see Chagas Disease
• Staphylococcal Infections
• STD see Sexually Transmitted Diseases
• Stomach Flu see Gastroenteritis
• Strep Throat see Streptococcal Infections
• Streptococcal Infections
• Syphilis
• Ticks see Tick Bites
• Toxoplasmosis see Parasitic Diseases
• Traveler's Health
• Tuberculosis
• Tularemia
• Tinea Infections
• Typhoid Fever
• Typhus

V-Z

• Vaccine Preventable Diseases see Immunization
• Viral Infections
• VRE see Bacterial Infections
• West Nile Virus see West Nile Virus
• West Nile Virus
• Whooping Cough
• Worms
• Yellow Fever
• Yeast Infections
• Zika Virus

Infections Resources
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