Murine typhus in Mexico City: report of an imported case.

Murine typhus is endemic in several countries. We herein report an imported case of murine typhus caused by Rickettsia typhi in Mexico City. This is the first report of a case after almost 20 years since the last report. The species was confirmed by DNA sequencing and phylogenetic reconstruction.

Murine Typhus with Marked Thrombocytopenia in a Child in Northern Greece and Literature Review.

We report a case of murine typhus in a 4-year-old boy living in northern Greece. Although the illness started with mild symptoms, a maculopapular rash appeared by the end of the first week of illness followed by marked thrombocytopenia. The detection of IgM antibodies against Rickettsia typhi in the patient's blood and a positive polymerase chain reaction result combined with sequencing confirmed the diagnosis of infection by Rickettsia typhi. Clinicians in northern Greece should be aware of the disease, even in cases presenting with no specific initial symptoms.

Typhus Group Rickettsiosis, Germany, 2010-20171.

Typhus group rickettsiosis is caused by the vectorborne bacteria Rickettsia typhi and R. prowazekii. R. typhi, which causes murine typhus, the less severe endemic form of typhus, is transmitted by fleas; R. prowazekii, which causes the severe epidemic form of typhus, is transmitted by body lice. To examine the immunology of human infection with typhus group rickettsiae, we retrospectively reviewed clinical signs and symptoms, laboratory changes, and travel destinations of 28 patients who had typhus group rickettsiosis diagnosed by the German Reference Center for Tropical Pathogens, Hamburg, Germany, during 2010-2017. Immunofluorescence assays of follow-up serum samples indicated simultaneous seroconversion of IgM, IgA, and IgG or concurrence in the first serum sample. Cytokine levels peaked during the second week of infection, coinciding with organ dysfunction and seroconversion. For 3 patients, R. typhi was detected by species-specific nested quantitative PCR. For all 28 patients, R. typhi was the most likely causative pathogen.

Reemergence of murine typhus in Galveston, Texas, USA, 2013.

Twelve patients with murine typhus were identified in Galveston, Texas, USA, in 2013. An isolate from 1 patient was confirmed to be Rickettsia typhi. Reemergence of murine typhus in Galveston emphasizes the importance of vector control and awareness of this disease by physicians and public health officials.

Murine typhus, Reunion, France, 2011-2013.

Murine typhus case was initially identified in Reunion, France, in 2012 in a tourist. Our investigation confirmed 8 autochthonous cases that occurred during January 2011-January 2013 in Reunion. Murine typhus should be considered in local patients and in travelers returning from Reunion who have fevers of unknown origin.

Murine typhus in child, Yucatan, Mexico.

A case of murine typhus in Yucatan was diagnosed in a child with nonspecific signs and symptoms. The finding of Rickettsia typhi increases the number of Rickettsia species identified in Yucatan and shows that studies are needed to determine the prevalence and incidence of rickettsioses in Mexico.

Three rickettsioses, Darnley Island, Australia.

We report 3 rickettsioses on Darnley Island, Australia, in the Torres Strait. In addition to previously described cases of Flinders Island spotted fever (Rickettsia honei strain "marmionii"), we describe 1 case of Queensland tick typhus (R. australis) and 2 cases of scrub typhus caused by a unique strain (Orientia tsutsugamushi).

Monitoring of humans and animals for the presence of various Rickettsiae and Coxiella burnetii by serological methods.

Serological examination of humans in Slovakia suspected of having rickettsial infections revealed the presence of antibodies to spotted fever group rickettsiae (R. conorii, R. slovaca, and R. typhi). Of interest is the finding of serological positivity to the newly recognized "IRS" agent. Antibodies to these rickettsiae and to C. burnetii were demonstrated also in domestic and hunting dogs and pet animals. These results confirm the occurrence and possible circulation of these rickettsiae and C. burnetii in the Slovak Republic.

Immunoblot studies to analyze antibody to the Rickettsia typhi group antigen in sera from patients with acute febrile cerebrovasculitis.

In 1986, an unusual syndrome of acute febrile cerebrovasculitis in the Piedmont Region of Virginia was reported. All patients had encephalopathy and prior exposure to both a sylvan environment and flea-infested animals. The initial serological studies suggested a rickettsial origin, corroborating clinical, epidemiological, and histopathological findings. Sera from four of five patients were subsequently studied by immunoblotting. Unabsorbed and absorbed sera were tested with electrophoresed and electroblotted Rickettsia typhi, Legionella bozemanii, and Proteus vulgaris OX19 antigens. The unabsorbed sera reacted with all three antigens. The P. vulgaris- and L. bozemanii-absorbed sera reacted with R. typhi only and without significantly less intensity. In contrast, the reactivity of R. typhi-absorbed sera was significantly lower with all three antigens. These results indicate that these patients had specific antibodies to a typhus group antigen. Although our findings suggest that a rickettsia of the typhus group may have caused this syndrome, no definitive diagnosis could be achieved because a rickettsial organism was not isolated.

Antigenic relationships among the rickettsiae of the spotted fever and typhus groups.

Using immunoblots to analyze antigenic relationships among the pathogenic spotted fever and typhus group rickettsiae, I found that the rickettsial lipopolysaccharide (LPS) was a group-specific antigen. All the rickettsiae examined had 135-kDa and 58-kDa protein antigens. The spotted fever rickettsiae and Rickettsia canada had, in addition, 190-kDa protein antigens which were antigenic analogs of previously described protective antigens of R. conorii and R. rickettsii.