Epidemiologic profile and clinical course of four confirmed rickettsiosis cases in Southern Mexico during 2016

Abstract

Key Clinical MessageDomestic animals can carry ticks or fleas, which constitute common vectors of rickettsial infections. The contact with them should be considered as suggestive of rickettsial infections in symptomatic patients. Misdiagnosis might occur in regions where other vector‐borne diseases are endemic. Anamnesis is essential for an accurate clinical diagnosis.

Clinical Manifestations in a Fatal Case of Probable Rickettsia and Leptospira Coinfection in Yucatan, Mexico

“…In 2011, in a reservoir seroprevalence study, the majority of dogs and cats slept outdoors, and 45.2% of the free-roaming dogs and 15.2% of the cats were found to be positive for Leptospira [8,13]; however, dogs may be involved in not only the transmission of Leptospira, but also that of Rickettsia, as dogs are in contact with wild animals (such as deer or wild swine), as well as with other dogs, cattle, and their human owners. It is not uncommon to find them carrying ectoparasites such as ticks which may transmit Rickettsia, as previously reported in the studied region [4].…”

“…Although initial clinical manifestations consisted mainly of signs and symptoms of unspecific acute, severe infections (e.g., fever, malaise, lymph node enlargement, hepatomegaly, and gastrointestinal manifestations), photophobia and progression to renal failure had previously been reported in severe leptospiral infections, while dermatologic manifestations and neurological impairment have been evidenced in fatal pediatric cases due to Rickettsia in the studied region [ 3 , 4 , 5 , 6 , 18 ]. Additionally, our patient presented with positive Kernig’s and Brudzinski’s signs consistent with leptospiral meningitis, which has been reported in approximately one quarter of cases among younger patients [ 9 ].…”

“…Therapy for Rickettsia should be initiated within five days after observation of symptoms consistent with the signs and the epidemiological context. Penicillin, which was administered to the patient before hospitalization, if used in correct dosage, could have been useful against Leptospira , but doxycycline is commonly considered the most effective antibiotic against Rickettsia and has also proven to be useful against Leptospira [ 4 , 20 ]. Unfortunately, in the presented case, treatment with doxycycline had been delayed until the drug was available, by which time the patient had already had severe nonrefractory damage.…”

“…Leptospirosis is a zoonotic disease caused by aerobic spirochetes [ 2 ], while rickettsiosis is an arthropod-borne disease caused by Gram-negative bacteria [ 3 ]. In the region where the case took place, severe and fatal Rickettsia infections in pediatric and adult patients have been associated with ticks carried by cats and dogs [ 4 ]. Rickettsiosis in humans is characterized by clinical signs including fever, rash, and lymphadenopathy along with symptoms including malaise, myalgia accompanied by vomiting, diarrhea, and headache.…”

Molecular identification of zoonotic Rickettsia species closely related to R. typhi, R. felis, & R. rickettsii in bats from Mexico

“…Bats were captured in X’matkuil, Yucatan (20.865927-89.623794) during September 2018 with three mist nets (12×2.6 m). This area is part of the south suburban area of the city of Merida, Yucatan, in which several cases of rickettsiosis have been documented 1 10 . Somatic measurements, age (juvenile or adult), species, and sex were recorded 11 .…”