Immaculada Pons

Seroprevalence of Bartonella spp. infection in HIV patients in Catalonia, Spain

BackgroundAlthough the first clinical descriptions of Bartonella infection were associated with immunocompromised patient with bacillary angiomatosis, we currently know that this organism is directly involved in diseases affecting a large number of patients, regardless of their immune status. Cat scratch disease, hepatic peliosis, and some cases of bacteraemia and endocarditis, are directly caused by some species of the genus Bartonella. The purpose of this study was to determinate the prevalence of IgG antibodies against Bartonella henselae and B. quintana in HIV patients and to identify the epidemiological factors involved.MethodsSerum samples were collected from HIV patients treated at Hospital de Sabadell. Antibodies to B. henselae and B. quintana from 340 patients were examined by indirect immunofluorescence assay (IFA). Significance levels for univariate statistical test were determined by the Mann-Whitney U test and χ2 test.ResultsOf 340 patients, 82 were women and 258 men, with a median age of 42.21 ± 10.35 years (range 16–86 years). Seventy-six (22.3%) patients reacted with one or more Bartonella antigens. Of all the factors concerning the seroprevalence rate being studied (age, sex, intravenous drugs use, alcohol consumption, CD4 levels, AIDS, HCV, HBV, residential area), only age was statistically significant.ConclusionA high percentage of HIV patients presents antibodies to Bartonella and is increasing with age.

Molecular detection of Rickettsia typhi in cats and fleas.

Background Rickettsia typhi is the etiological agent of murine typhus (MT), a disease transmitted by two cycles: rat-flea-rat, and peridomestic cycle. Murine typhus is often misdiagnosed and underreported. A correct diagnosis is important because MT can cause severe illness and death. Our previous seroprevalence results pointed to presence of human R . typhi infection in our region; however, no clinical case has been reported. Although cats have been related to MT, no naturally infected cat has been described. The aim of the study is to confirm the existence of R . typhi in our location analyzing its presence in cats and fleas. Methodology/Principal Findings 221 cats and 80 fleas were collected from Veterinary clinics, shelters, and the street (2001-2009). Variables surveyed were: date of collection, age, sex, municipality, living place, outdoor activities, demographic area, healthy status, contact with animals, and ectoparasite infestation. IgG against R . typhi were evaluated by indirect immunofluorescence assay. Molecular detection in cats and fleas was performed by real-time PCR. Cultures were performed in those cats with positive molecular detection. Statistical analysis was carried out using SPSS. A p < 0.05 was considered significant. Thirty-five (15.8%) cats were seropositive. There were no significant associations among seropositivity and any variables. R . typhi was detected in 5 blood and 2 cultures. High titres and molecular detection were observed in stray cats and pets, as well as in spring and winter. All fleas were Ctenocephalides felis. R . typhi was detected in 44 fleas (55%), from shelters and pets. Co-infection with R . felis was observed. Conclusions Although no clinical case has been described in this area, the presence of R . typhi in cats and fleas is demonstrated. Moreover, a considerable percentage of those animals lived in households. To our knowledge, this is the first time R . typhi is detected in naturally infected cats.

The role of cats in the eco-epidemiology of spotted fever group diseases

BackgroundMediterranean Spotted Fever (MSF), whose etiological agent is R. conorii, is one of the oldest described vector-borne infectious diseases. Although it is endemic in the Mediterranean area, clinical cases have also been reported in other regions. R. massiliae- Bar29 is related to MSF cases. This strain is distributed worldwide. R. conorii and R. massiliae- Bar29 are transmitted by ticks. Dogs are considered the sentinel of R. conorii infection. Cats could also be involved in their transmission. Rickettsia felis, etiological agent of Flea-borne spotted fever, is mainly transmitted by the cat flea, Ctenocephalides felis. Up to now, the role of cats in its transmission is not entirely elucidated. The aim of the study is to analyze the infection in cats by these microorganisms.MethodsThe study was undertaken in Northeastern Spain. Twenty municipalities of seven regions participated in the study. 212 cats (pets and stray cats) were analyzed. Variables surveyed were: date of collection, age, sex, municipality, source, living place, outdoor activities, health status, type of disease, contact with other animals, and ectoparasite infestation. Sera were evaluated by indirect immunofluorescence antibody assay (IFA). Molecular detection (real-time PCR and sequencing) and cultures were performed on blood samples.ResultsThere were 59 (27.8%) cats seroreactive to one or more microorganisms. Considering cross-reactions, the seroprevalences were 15.6%-19.5% (R. massiliae-Bar29), 1.9%-6.2% (R. conorii), and 5.2%-7.5% (R. felis). A weak association was observed between SFG seropositivity and tick infestation. Ticks found on seropositive cats were Rhipicephalus pusillus, R. sanguineus and R. turanicus. DNA of Rickettsia was detected in 23 cats. 21 of them could be sequenced. Sequences obtained were identical to those sequences of SFG rickettsiae similar to R. conorii and R. massiliae. No amplification of R. felis was obtained.ConclusionsCats can be infected by SFG rickettsiae and produce antibodies against them. Cats may play a role in the transmission cycle of R. conorii and R. massiliae-Bar29, although the role in the R. felis cycle needs further analysis.

Seroprevalence of Rickettsia typhi and Rickettsia felis in dogs from north-eastern Spain.

Rickettsia typhi is the aetiological agent of murine typhus (MT). This disease is often acute and mild, although some fatal cases have been observed [1]. In Spain, clinical cases and serological evidence of exposure to R. typhi in humans have been described [2,3]. In the past, MT has been associated with rodents and rat fleas. Later, a peridomestic animal cycle involving cats, dogs, opossums and their fleas [1] was described. In Spain, R. typhi seropositivity has been shown in dogs [4] from the central region. Rickettsia felis, transmitted by fleas, produces flea-borne spotted fever, a clinical syndrome indistinguishable from MT. Serological evidence of R. felis infection in humans has been observed in Spain [2,3]. R. felis has been detected in fleas commonly found on domestic cats and dogs in Spain [5]. Prevention of these infections depends on recognition of routes of transmission, risk factors for infection, and reservoirs. The aim of this study was to determine the prevalence of both rickettsiae in dog populations from the north-east of Spain.

The dog as an epidemiological marker of Rickettsia conorii infection.

Department of Medicine, Universitat Auto`noma de Barcelona(UAB), Barcelona, SpainINTRODUCTIONDogs are considered to be the sentinels of Rick-ettsia conorii infection, which is the causative agentof Mediterranean spotted fever, one of the mostprevalent tick-transmitted disease in our area. It istransmitted by the dog tick, Rhipicephalus sanguin-eus. This tick is relatively host-specific, and rarelyfeeds on people unless its preferred host—thedog—is not available [1]. This tick is active fromspring to autumn, but climatic changes influenceits activity and, consequently, Mediterraneanspotted fever epidemiology [2].As canine serology constitutes a useful epide-miological marker [3], the objective of this studywas to evaluate the presence of R. conorii in dogpopulations subjected to different exposure toR. sanguineus. For this purpose, three seroepide-miological studies were designed: serosurvey indogs with close contact with ticks, seasonaldifferences in antibodies to R. conorii in dogssubjected to natural tick infestation, and a com-parison of canine seroprevalence rates obtained in1997 and in 2007 in dogs regularly treated forectoparasites.MATERIALS AND METHODS

Serological evidence of Bartonella henselae infection in healthy people in Catalonia, Spain

Cat scratch disease (CSD), bacillary angiomatosis, hepatic peliosis and some cases of bacteraemia, endocarditis, and osteomyelitis are directly caused by some species of the genus Bartonella. The purpose of this study was to determine the prevalence of IgG antibodies against Bartonella henselae in healthy people and to identify the epidemiological factors involved. Serum samples from 218 patients were examined by indirect immunofluorescence assay (IFA). Significance levels for univariate statistical analysis were determined by the Mann-Whitney U test, chi2 test and Fishers exact test. Of 218 patients, 99 were female and 119 male, with a median age of 34.36 years (range 0-91 years). Nineteen (8.7%) reacted with B. henselae antigens. Of all the factors concerning the seroprevalence rate being studied (age, sex, contact with animals, residential area), only age was statistically significant. Our serological data seems to indicate that B. henselae is present in Catalonia and could be transmitted to humans.

Diagnóstico microbiológico de las infecciones por patógenos bacterianos emergentes: Anaplasma, Bartonella, Rickettsia, Tropheryma whipplei

Ehrlichia/ Anaplasma, Bartonella, Rickettsia y Tropheryma whipplei (antes llamado whippelii ) constituyen un claro ejemplo de bacterias de dificil cultivo que causan enfermedades emergentes y reemergentes de potencial gravedad e importancia en salud publica. En los ultimos anos la disponibilidad de tecnicas de biologia molecular y de cultivo celular ha permitido que muchas de estas especies se hayan implicado en patologia humana. El desarrollo de todos estos aspectos, con especial hincapie en las tecnicas microbiologicas y criterios diagnosticos, se puede consultar en el procedimiento microbiologico SEIMC numero 27: “Diagnostico microbiologico de las infecciones por patogenos bacterianos emergentes: Anaplasma, Bartonella, Rickettsia y Tropheryma whippelii ” (2.a ed., 2007) ( www.seimc.org/documentos/protocolos/microbiologia/ ).

Endemic meningococcal disease in Cerdanyola, Spain, 1987–93: molecular epidemiology of the isolates of Neisseria meningitidis

OBJECTIVE: To establish the relationships between 30 Neisseria meningitidis strains isolated in Cerdanyola (Spain) from 30 out of 36 sporadic cases of meningococcal disease (MD) during 1987--93 and their spread in this population by multilocus enzyme electrophoresis (MEE) and by pulsed-field gel electrophoresis (PFGE), and to evaluate the usefulness of PFGE versus serologic typing methods and MEE as an alternative epidemiologic marker to study meningococcal infection. METHODS: Serotyping, electrophoretic mobility of seven isoenzymes determined by MEE and chromosomal DNA macrorestriction with NheI resolved by PFGE were analyzed. RESULTS: Of these 30 strains, 25 were serogroup B and the remaining five were serogroup C, with the 4:P1.15 and the 2b:NT as the most common antigenic phenotypes, respectively. There were 13 electrophoretic types (ETs) by MEE, with 14 isolates showing an identical ET, 8. Sixteen pulse types (PTs) were generated by PFGE. The 14 ET 8 isolates were clustered into six PTs, A1, A2, A4, A5, A6 and A8. However, by combining both methods, 19 genetically distinct groups were obtained. Eleven of these groups (20 serogroup B strains) and two of these (four serogroup C strains) were genetically related. CONCLUSIONS: We conclude that, according to the clonal population structure, these 30 N. meningitidis strains are heterogeneous although a great number are related. Moreover, PFGE is a useful method to establish clonal structure in N. meningitidis strains under endemic conditions. Finer discrimination of these strains was achieved by combining both MEE and PFGE methods.

The role of dogs in the eco-epidemiology of Rickettsia typhi, etiological agent of Murine typhus

Rickettsia typhi, etiological agent of Murine typhus (MT), is transmitted to humans from an animal reservoir through two cycles: a classic rat-flea-rat cycle, and a peridomestic animal cycle. There are not many studies concerning which animals are involved in the peridomestic cycle, and most of them are focused on cats. The aim of this study was to determine the presence of R. typhi in dogs, not only by serological methods but also by direct methods such as culture and molecular detection. Two hundred and one dog blood samples were collected from Veterinary clinics, kennels, and shelters in Northeastern Spain (2006-2008). Age, sex, municipality, living place, healthy status, contact with animals, and ectoparasite infestations were surveyed. IgG was measured by IFA. Titers ≥ 1/64 were considered positive. Cultures were carried out using samples of dogs with titers ≥ 1/128. The molecular detection was performed by real-time PCR. Nine dogs (4.5%) were positive according to IFA (5: 1/64; 3: 1/128; 1: 1/512). There were no significant differences in the rates of antibodies related to any of the variables. Rickettsial DNA was detected in two cultures. Sequences obtained were identical to those of R. typhi. The results show direct and indirect evidences of the presence of R. typhi infection in dogs.

Rickettsia felis in Fleas from Catalonia (Northeast Spain)

INTRODUCTION Rickettsia felis produces a syndrome indistinguishable from murine typhus, which has been described in Spain. R. felis is transmitted to humans by fleas. Although no clinical case has been described so far, serologic evidence of infections in humans, cats, and dogs has been obtained in our area. However, no study has been conducted regarding its presence in vectors. Recognition of routes of transmission is of great importance to prevent infection in humans. Taking into account these results, R. felis seems to be present in animals that are in contact with humans. The aim of this study was to determine the presence of R. felis in the fleas of cats and dogs from Northeast Spain, to show the presence of peridomestic cycle in our area. MATERIALS AND METHODS Between May 2006 and July 2008, 78 fleas were collected. Sixty-three fleas were recovered from kennels. Most of them were collected from cages and a few of them on dogs and cats living in kennels. Fifteen fleas were collected from dogs and cats attended at a veterinary clinic. Fleas were rinsed with ethanol, dried, identified, and stored at 4°C. DNA was extracted from each flea individually. Rickettsial DNA was determined by quantitative real-time polymerase chain reaction. OmpB-specific primers and molecular beacon probes targeting specifically R. felis were used. RESULTS All 78 fleas were identified as Ctenocephalides felis. R. felis was detected in 34 (43.6%) fleas. No nucleic acids were amplified from negative controls and expected results were obtained from positive controls. Eight positive samples were also confirmed by sequencing. CONCLUSIONS R. felis was found in a high percentage of Ct. felis from cats and dogs. It seems that there is a peridomestic cycle in Northeast Spain, which would allow contact of R. felis with humans.