Macular and papular cold-damage disease (typhus) is an acute pestilential disease caused by Rickettsia. Epidemic macular and papular cold-damage disease is caused by Rickettsia prowazekii, transmitted by body lice, and is more common in winter and spring. Endemic spotted cold-damage disease is caused by Rickettsia mooseri infection, with rats and rat fleas as vectors, and is more common in summer and autumn. The endemic form is milder in severity compared to the epidemic form.

bubble_chart Clinical Manifestations

1. The onset is abrupt, with fever reaching 39-40°C within 1-2 days and persisting at high levels for about a week.
2. The rash appears between days 3-6, predominantly on the trunk and both upper arms, spreading across the entire body within hours, peaking on day 8, rarely affecting the face, and fading by day 12, leaving pigmentation.
3. Neurological symptoms are prominent, including severe headache, dizziness, insomnia, dysphoria, muscle pain, possible limb tremor, impaired consciousness, and meningeal irritation signs.
4. When the cardiovascular system is involved, the pulse accelerates, and myocarditis or circulatory failure may occur.
5. Splenomegaly is common, while hepatomegaly is rare.

bubble_chart Auxiliary Examination

1. The blood picture shows normal or slightly elevated white blood cells, with a minority showing decreased levels. Eosinophils are reduced or absent, platelet counts are decreased, and there may be grade I or grade II anemia. 2. Weil-Felix reaction: An antibody titer of 1:160 is diagnostically significant. A positive reaction may appear as early as the 5th day of illness, but generally occurs during the 2nd to 3rd week of the disease course. In endemic macula and papule cold-damage disease, the titer is lower and the duration of positivity is shorter. 3. Rickettsial agglutination test: For epidemic macula and papule cold-damage disease, agglutination is performed using Proteus OX19 antigen with the patient's serum. A positive reaction (titer ≥1:40) can often be detected by the 5th day of illness, with the titer declining after one month. For the endemic form, agglutination must be performed using Rickettsia mooseri antigen. 4. Complement fixation test: Using Proteus OX19 antigen with the patient's serum, this test is highly specific and does not cross-react with the endemic form, making it useful for distinguishing between epidemic and endemic macula and papule cold-damage disease. A titer of ≥1:40 is considered positive. 5. Animal inoculation test: Guinea pigs inoculated with rickettsiae show severe scrotal swelling (grade I for Proteus OX19, severe for Rickettsia mooseri) within 5–6 days.

bubble_chart Diagnosis

Epidemiological history: epidemic season, local epidemic situation, human body lice or rodent fleas in Chinese Taxillus Herb.

bubble_chart Treatment Measures

(1) General and Symptomatic Treatment Isolate strictly and individually, bathe, change clothes, trim hair, and eliminate lice and fleas. Bed rest is advised. Maintain oral and skin hygiene. Avoid large doses of antipyretics for high fever to prevent excessive sweating and collapse. For severe cases, consider using adrenal corticosteroids (hydrocortisone, prednisone, or dexamethasone) and ensure adequate hydration. (2) Pathogenic Treatment 1. Chloramphenicol: 50 mg/(kg·d) for adults, 25 mg/(kg·d) for children, divided into 4 oral doses, continued for at least 7 days. 2. Tetracycline antibiotics (aureomycin, terramycin, and tetracycline) are highly effective for this condition. Dose: 30–40 mg/(kg·d), course of treatment: 5–7 days. For children under 8 years old, Jinfu tetracycline. 3. TMP (trimethoprim, an antibacterial synergist): 5–10 mg/(kg·d), divided into 2 daily doses. Efficacy is enhanced when taken with tetracycline antibiotics. 4. Doxycycline: 2–4 mg/(kg·d), taken once or twice daily for 3 consecutive days.

bubble_chart Prevention

(1) Strengthen personal and environmental hygiene, and eliminate rats, lice, and fleas. (2) Conduct preventive vaccination in affected areas to alleviate symptoms and shorten the course of the disease. (3) Strictly isolate patients and carry out rat, lice, and flea control on their clothing and living quarters.