hydatid disease, brucellosis,leptospirosis, typhus fever, measels, varicella
| Feature | Hydatid | Brucellosis | Leptospirosis | Typhus | Measles | Varicella |
|---|---|---|---|---|---|---|
| Pathogen | E. granulosus (tapeworm) | Brucella spp. (G-ve coccobacillus) | Leptospira interrogans (spirochete) | Rickettsia spp. (obligate intracellular) | Measles virus (RNA) | VZV (DNA herpesvirus) |
| Transmission | Dog feces → oral | Unpasteurized dairy/meat; inhalation | Contact with animal urine/contaminated water | Louse/flea/mite vector | Respiratory droplets | Airborne + direct contact |
| Key clinical clue | Liver cyst in sheep farmer | Undulant fever + sacroiliitis | Conjunctival suffusion + AKI + jaundice | Rash on trunk + eschar (scrub) | Koplik spots + centrifugal rash | "Dewdrop on rose petal" + all lesion stages simultaneously |
| Diagnosis | CT + serology | SAT agglutination / blood culture | MAT (paired sera) / PCR | IFA serology / PCR of eschar | Clinical + IgM serology | Clinical / PCR vesicle fluid |
| Treatment | Albendazole + PAIR surgery | Doxycycline + rifampin or streptomycin × 6 weeks | Doxycycline (mild) / IV penicillin or ceftriaxone (severe) | Doxycycline (first-line ALL types) | Supportive + Vitamin A | Valacyclovir/famciclovir (adults); IV acyclovir (severe/immunocompromised) |
| Key complication | Anaphylaxis on rupture | Endocarditis, spondylodiscitis | AKI, ARDS, Weil's disease | Encephalitis (up to 80% in epidemic typhus) | SSPE, giant cell pneumonia | Varicella pneumonia, neonatal varicella |
SLE