ENDEMIC IN A LIBYAN ADULT

CASE REPORT

ENDEMIC TYPHUS () IN AN 18 YEAR OLD LIBYAN ADULT

Pavan Sable1 and Mohammed Maayuf2

1Liverpool School of Tropical Medicine, Liverpool, UK; 2Department of Infectious Diseases, Misurata Central Hospital, Misurata, Libya

Abstract. We present a case of an 18 year old Libyan with a history of fever, frontal headache, bodyache, malaise, abdominal pain, and , followed by macular to maculopapular rash. A diagnosis of endemic typhus (murine typhus) was made based on the typical clinical findings and epidemiological history given by the patient. Routine blood investigations were inconclusive and a chest x-ray was normal. The patient was treated by oral . The patient responded favorably to treat- ment.

INTRODUCTION tropical, and temperate zones throughout the world, principally in Southeast Asia, Endemic typhus (murine typhus) is a Africa, Central America, and the Mediterra- rickettsial infection caused by typhi. nean region. The disease is seen in seaports, The disease is transmitted by a , urban areas, and certain rural areas infested Xenopsylla cheopsis. However, other rodents by wild eg, grain storage facilities (Civen and their ectoparasites have been implicated and Ngo, 2008). Murine typhus is often un- as alternative competent reservoirs and vec- recognized and underreported in Africa; tors of R. typhi (Traub et al, 1978; Loftis et al, however, from northern Africa, 7 cases in 2006). House mice are highly susceptible to Tunisia were documented in 2005 (Letaief experimental infection with R. typhi (Philip et al, 2005) and in 2 cases in Algeria (Mouffok and Parker, 1938) and mice, in the absence et al, 2008).The seasonal incidence peak oc- of rats, have been implicated in several out- curs in late spring and early summer (Fauci breaks of murine typhus (Truab et al, 1978). et al, 1998). Globally, a drop in endemic ty- In United States, contrary to the classic rat- phus cases has occurred because of reduc- flea-rat cycle, the most important reservoirs tion in the oriental rat flea, X. cheopsis, by of infection are opossums and cats; the cat the use of DDT and improved rat control flea, Ctenocephalides felis, has been identified (Wallace et al, 1998). as the principal vector (Sorvillo et al, 1993). Endemic typhus occurs in tropical, sub- CASE REPORT

Correspondence: Dr Pavan Sable, DTM&H stu- An 18 year old unmarried Libyan pre- dent Liverpool School of Tropical Medicine, Pem- sented with a history of fever, frontal head- broke Place, L3 5QA, United Kingdom. ache, bodyache, malaise, abdominal pain, Tel: 0044 75 0174 2112 nausea and vomiting, followed by a macu- E-mail: [email protected] lar to maculopapular rash. The rash was ini-

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Routine blood investigations were not conclusive, urine examination and chest x- ray showed no major abnormalities. No se- rological tests were done. The diagnosis was made on clinical grounds and response to treatment. The patient was treated with doxycycline and his condition gradually improved.

DISCUSSION

Endemic typhus was postulated by Maxcy in 1926 to be a distinct disease, with rats as a reservoir and as the vector. Fig 1–Maculopapular rash of the right arm. Dyer isolated , the causative agents from rats and fleas in 1931 (Fauci et al, 1998). Endemic typhus is more prevalent in warm and coastal areas (Longmore et al, 2005). The patient was a resident of the periurban area of Misurata City where rat infestation is fairly common and the hous- ing conditions are favorable for transmis- sion. The actual mode of transmission is not the bite of the rat flea but by inoculation onto the skin feces of infected fleas, and possibly by inhalation of dried infective feces. How- ever, some authors (Shulman et al, 1997; Last and Wallace et al, 1998) have reported the Fig 2–Rash of the right leg. bite of infected fleas as a mode of transmis- sion as well. Although patients seldom re- call a bite or exposure to fleas, but exposure tially macular, started on the arms and legs, to animals such as cats or rats is usually then spread to the rest of the body, includ- present (Fauci et al, 1998). Dog and cat fleas ing the palms and soles. No eschar was seen. have been suspected as occasional vectors was absent. for humans. This case had documented close The patient gave a history of regular contact with cats and sheep prior to the on- contact with sheep and cats, but denied a set of illness. There have been no docu- history of insect bites. The patient also re- mented cases of person to person spread ported living in poor housing conditions and (Wallace et al, 1998). the presence of rat burrows and rat infesta- The incubation period ranges from 1 to tion around the house. The patient gave no 2 weeks, which is fairly constant (Park, 2005; history of a similar illness or contact with Bannister et al, 1996). The clinical features in- similar cases in past. clude fever, persistent headache, ,

786 Vol 40 No. 4 July 2009 ENDEMIC TYPHUS IN A LIBYAN ADULT nausea, vomiting, abdominal pain and or is usually effective macular rash or maculopapular rash (Axford (Souhami and Moxham, 1997). The drugs and O’ Callaghan, 1996). The initial rash is inhibit the organism’s growth rather than often seen in the axilla or inner surface of kill them; general supportive measures and the arm. Subsequently, the rash becomes the host’s immune response are important maculo-papular, involving the trunk more factors in recovery. Doxycycline is the drug than the extremities (Fauci et al, 1998). The of choice (Hardman and Limbird, 1995). signs and symptoms resemble that of louse Permanent sequelae are rare, and one at- borne typhus, but are milder, shorter in du- tack confers immunity (Shulman et al, 1997; ration and murine typhus is rarely fatal Wallace et al, 1998). Residual insecticide ap- (Axford and O’ Callaghan, 1996; Shulman plication (such as with malathion) and ro- et al, 1997; Haslett et al, 2002). The main pa- dent control measures should be imple- thology with this disease is endovasculitis mented to control the disease in the com- (Bannister et al, 1996), which causes a rash munity. No endemic typhus vaccine is cur- and bleeding. Rarely, the disease may rently available (Park, 2005). present as an acute febrile illness and retini- tis or neuroretinits (Hudson et al, 1997). REFERENCES Complications are rare and mortality is less st than 1% (Shulman et al, 1997). Axford JS, O’Callaghan CA, eds. Medicine. 1 ed. Sussex: Blackwell Science, 1996; 2: 76. The diagnosis is usually made by clini- cal findings, epidemiological history and Bannister BA, Begg NT, Gillespie SH. Infectious st response to treatment (Shulman et al, 1997). disease. 1 ed. Oxford: Blackwell science, 1996: 378-9. Sometimes a travel history may point to the diagnosis (Bannister et al, 1996). An exact di- Civen R, Ngo V. Murine typhus: an unrecognized agnosis is often difficult (Longmore et al, suburban vectorborne disease. Clin Infect Dis 2008; 46: 913-8. 2005). Serology is the mainstay of laboratory diagnosis and routine blood tests are usu- Fauci AS, Braunwald E, Isselbacher K, et al, eds. ally unhelpful (Haslett et al, 2002). An IFA Harrison’s principles of internal medicine, Vol 1. 14th ed. New York: McGraw Hill, 1998: test is the widely used serologic diagnostic 1045-52. method. However, R. typhi may cross-react with other rickettsial antigens, including Haslett C, Chilvers ER, Hunter JA, et al, eds. Davidson’s principles and practice of medi- group (SFG) rickettsiae, and cine. 19th ed. Philadelphia: Churchill especially, R. prowazekii, the agent of epi- Livingstone, 2002: 62-4. demic typhus (La Scola et al, 2000). The Hardman JG, Limbird LE. Goodmans and complement fixation test (CFT) and Weil- Gilman’s the pharmacological basis of thera- Felix reaction are also used, but both lack peutics. 10th ed (International edition). New sensitivity. Immunohistology may demon- Delhi: McGraw Hill, 1995: 1240-1. strate rickettsia in the skin lesions. Polychro- Hudson HL, Thach AB, Lopez PF. Retinal mani- matic stains, such as Giemsa stain, have been festations of acute murine typhus. Int used to identify intracellular rickettsia Ophthalmol 1997; 21: 121-6. (Shulman et al, 1997). PCR has a high sensi- La Scola B, Rydkina L, Ndihokubwayo JB, Vene tivity and specificity for the diagnosis of rick- S, Raoult D. Serological differentiation of ettsial infections (Singhsilarak et al, 2005; murine typhus and using Stenos et al, 2005). cross-adsorption and Western blotting. Clin Antibiotic treatment with Diagn Lab Immunol 2000; 7: 612-6.

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Letaief AO, Kaabia N, Chakroun M, Khalifa M, ed. Philadelphia: WB Saunders, 1997: 430-42. Bouzouaia N, Jemni L. Clinical and labora- Singhsilarak T, Leowattana W, Looareesuwan S, tory features of murine typhus in central et al. Detection of in Tunisia: a report of seven cases. Int J Infect clinical samples by a quantitative real-time Dis 2005; 9: 331-4. polymerase chain reaction. Am J Trop Med Loftis AD, Reeves WK, Szumlas DE, et al. Sur- Hyg 2005; 72: 640-1. veillance of Egyptian fleas for agents of Souhami RL, Moxham J. Textbook of medicine. public health significance: Anaplasma, Bar- 3rd ed. Philadelphia: Churchill Livingstone, tonella, Coxiella, Ehrlichia, Rickettsia, and 1997: 258-60. . Am J Trop Med Hyg 2006; 75: Sorvillo FJ, Gondo B, Emmons R, et al. A subur- 41-8. ban focus of endemic typhus in Los Ange- Long More M, Wilkinson IB, Rajagopalan S. Ox- les County: association with seropositive th ford handbook of clinical medicine. 6 ed. domestic cats and opossums. Am J Trop Med Oxford: Oxford University, 2005: 604-5. Hyg 1993; 48: 269-73. Mouffok N, Parola P, Raoult D. Murine Typhus, Stenos J, Graves SR, Unsworth NB. A highly sen- Algeria. Emerg Infect Dis 2008; 14: 676-8. sitive and specific real-time PCR assay for Park K. Park’s textbook of preventive and social the detection of spotted fever and typhus medicine. 18th ed. Jabalpur: Bhanot, 2005: group rickettsiae. Am J Trop Med Hyg 2005; 240. 73: 1083-5. Philip CB, Parker RR. The persistence of the vi- Traub R, Wisseman CL Jr, Farhang-Azad A. The ruses of endemic (murine) typhus, Rocky ecology of murine typhus: a critical review. Mountain spotted fever, and boutonneuse Trop Dis Bull 1978; 75: 237-317. fever in tissues of experimental animals. Last JM, Wallace RB, Doebbling BN, et al. eds. Public Health Rep 1938; 53: 1246-51. Maxcy-Rosenau-Last Public health and pre- Shulman ST, Phair JP, Peterson L, et al. Biological ventive medicine. 14th ed. New York: and clinical basis of infectious diseases. 5th McGraw Hill, 1998: 304-9.

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