# Endemic Flea-Borne and Tick-Borne Typhus - Category: infectious - Review status: reviewed (every claim checked against a document named on this page) - Sources: CDC Yellow Book 2024: Rickettsial Infections · CDC Yellow Book 2026: Rickettsial Diseases (NCBI Bookshelf NBK620978), Treatment · Egyptian National Drug Formulary (Antimicrobial Chapter 2023) · Egyptian National Drug Formulary - Antimicrobial 2023 (chloramphenicol monograph) - Verified date: 2026-08 ## Verified against - Egyptian National Drug Formulary - Antimicrobial 2023 - CDC Yellow Book 2026: Rickettsial Diseases (NCBI Bookshelf NBK620978), Treatment ## Treatment metadata - Doxycycline — 100 mg — oral.solid ## Complete treatment card ```text ENDEMIC FLEA-BORNE AND TICK-BORNE TYPHUS Sources: CDC Yellow Book 2024: Rickettsial Infections · CDC Yellow Book 2026: Rickettsial Diseases (NCBI Bookshelf NBK620978), Treatment · Egyptian National Drug Formulary (Antimicrobial Chapter 2023) · Egyptian National Drug Formulary - Antimicrobial 2023 (chloramphenicol monograph) Review status: REVIEWED against 2 sources listed above (2026-08) IS IT THIS? - reference only, to read alongside your own examination RED FLAGS (2) - Start treatment as soon as rickettsial disease is suspected; never withhold it pending confirmatory testing, because some infections progress rapidly - Rocky Mountain spotted fever, scrub typhus, Mediterranean spotted fever, murine typhus and epidemic typhus can all be life-threatening if antibiotics are delayed SYMPTOMS - what the patient reports (6) - Murine typhus usually presents as a moderately severe but otherwise non-specific febrile illness [fever] - About half develop a maculopapular rash, generally appearing on the trunk [rash] - Untreated, the fever can persist for up to 2 weeks [fever] - The classic rickettsial triad is fever, headache and rash, but these are variably present and the triad is not a reliable way to diagnose [fever · headache · rash] - Symptoms common across rickettsial infections are fever, headache, malaise, rash, nausea or vomiting, typically within 1 week of infection [fever · headache · malaise · nausea · rash · vomiting] - Incubation for most rickettsial disease is 5 to 10 days, so a traveller falls ill during the trip or within 1 to 2 weeks of getting home SIGNS - what you find (2) - Many rickettsioses show a maculopapular, vesicular or petechial rash, or a dark necrotic eschar at the bite site - but murine typhus is not an eschar disease [blisters · necrosis · petechiae · rash · vesicles] - Organ failure can develop and death does occur, though it is generally less severe than Rocky Mountain spotted fever or scrub typhus [fever] TESTS (4) - Serology confirms retrospectively: a 4-fold or greater rise in indirect immunofluorescence antibody titre between paired sera taken 2 to 4 weeks apart - Cross-reacting antigens may limit serology to the group or genus rather than the species - PCR of a whole blood specimen is usually positive only once the disease has advanced and the patient is severely ill - Where an eschar is present, PCR on an eschar swab or biopsy is sensitive and species-specific IF NOT THIS - what else fits (5) - Rickettsia typhi is flea-borne, found worldwide but especially around urban port cities and coastal areas with large rodent populations - Ask about flea-infested cats, dogs or peridomestic rodents; murine typhus is reported in travellers returning from Asia, Africa and the Mediterranean Basin - Other rickettsioses to weigh: African tick bite fever, Mediterranean spotted fever, scrub typhus, Rocky Mountain spotted fever, epidemic (louse-borne) typhus, rickettsialpox, ehrlichiosis and anaplasmosis - Cytopenias, particularly leukopenia and thrombocytopenia, point towards ehrlichiosis or anaplasmosis rather than typhus - Early rickettsial illness looks like other tropical diseases sharing the same geography and season Source CDC Yellow Book 2026 "Rickettsial Diseases" (NBK620978) - the rickettsial chapter; endemic (murine, flea-borne) typhus is Rickettsia typhi within it, and this card is scoped to that plus the shared rickettsial features Status traced to the source above 1. DOXYCYCLINE [1st line] Adult 100 mg orally twice daily - At least 5 to 7 days Peds 2.2 mg/kg/dose (Children < 45 kg: 2.2 mg/kg per dose orally twice daily. Children >= 45 kg: 100 mg orally twice daily. Doxycycline is first-line for rickettsial infections in children of any age.) 3kg -> 6.6 mg/dose 4kg -> 8.8 mg/dose 5kg -> 11 mg/dose 6kg -> 13.2 mg/dose 7kg -> 15.4 mg/dose 8kg -> 17.6 mg/dose 9kg -> 19.8 mg/dose 10kg -> 22 mg/dose 11kg -> 24.2 mg/dose 12kg -> 26.4 mg/dose 13kg -> 28.6 mg/dose 14kg -> 30.8 mg/dose 15kg -> 33 mg/dose 16kg -> 35.2 mg/dose 17kg -> 37.4 mg/dose 18kg -> 39.6 mg/dose 19kg -> 41.8 mg/dose 20kg -> 44 mg/dose 21kg -> 46.2 mg/dose 22kg -> 48.4 mg/dose 23kg -> 50.6 mg/dose 24kg -> 52.8 mg/dose 25kg -> 55 mg/dose 26kg -> 57.2 mg/dose 27kg -> 59.4 mg/dose 28kg -> 61.6 mg/dose 29kg -> 63.8 mg/dose 30kg -> 66 mg/dose 31kg -> 68.2 mg/dose 32kg -> 70.4 mg/dose 33kg -> 72.6 mg/dose 34kg -> 74.8 mg/dose 35kg -> 77 mg/dose 36kg -> 79.2 mg/dose 37kg -> 81.4 mg/dose 38kg -> 83.6 mg/dose 39kg -> 85.8 mg/dose 40kg -> 88 mg/dose 41kg -> 90.2 mg/dose 42kg -> 92.4 mg/dose 43kg -> 94.6 mg/dose 44kg -> 96.8 mg/dose 45kg -> 99 mg/dose 46kg -> 101.2 mg/dose 47kg -> 103.4 mg/dose 48kg -> 105.6 mg/dose 49kg -> 107.8 mg/dose 50kg -> 110 mg/dose Source Egyptian National Drug Formulary - Antimicrobial 2023 (doxycycline monograph): adult "Usual dosage range: Oral: IR and most ER formulations: 100 to 200 mg/day in 1 to 2 divided doses" with 100 mg capsules, and paediatric "Children and Adolescents: Oral, IV: 2.2 mg/kg/dose every 12 hours, maximum dose: 100 mg/dose". The rickettsial indication and the course length are from the CDC Yellow Book 2026 rickettsial diseases chapter (NCBI Bookshelf NBK620978), now on disk, which states: "Doxycycline is the treatment of choice for all rickettsial infections (100 mg by mouth twice daily for a minimum of 5-7 days; or 2.2 mg/kg by mouth twice daily for children <45 kg)". Why Doxycycline is the definitive drug of choice for all rickettsial infections (murine typhus and tick-borne typhus) across all age groups, as short courses (< 14 days) do not cause dental staining. Caution In pregnancy the Yellow Book names chloramphenicol rather than azithromycin. In breastfeeding, the Egyptian formulary says a short doxycycline course is probably not harmful - so it is not an absolute bar. Initiate treatment immediately upon clinical suspicion of rickettsial typhus; delaying doxycycline therapy increases risk of severe organ dysfunction and mortality. Administer with food and plenty of water in an upright position to prevent esophageal irritation and ulceration. Advise patients to avoid direct sun exposure due to photosensitivity risk. Egypt FARCODOXIN 100MG 10 CAPS. PHARCO 11.00 EGP (1.10/unit) DOXY M.R.100 MG 10 CAPS. ADWIA 12.00 EGP (1.20/unit) GRANUDOXY 100MG 10 F.C. TAB. GLOBAL NAPI P... 12.00 EGP (1.20/unit) DOXYDOX 100 MG 10 CAPS. EIPICO 23.00 EGP (2.30/unit) DOXYMYCIN 100 MG 10 CAPS. EL NILE. 30.00 EGP (3.00/unit) TABOCINE 100MG 10 CAPS. TABUK PHARMAC... 46.00 EGP (4.60/unit) VIBRAMYCIN 100MG 10 CAPS. PFIZER 65.00 EGP (6.50/unit) Prices are indicative (dataset snapshot 2026-06); verify with the pharmacy. ``` --- Dawaa Reference is a reference for prescribers, not a medical device, and does not replace clinical judgement. [Privacy policy](/privacy)