Epidemiological characteristics of spotted fever in Israel over 26 years

Spotted Fever Group Rickettsioses in Israel, 2010-2019

In a multicenter, nationwide, retrospective study of patients hospitalized with spotted fever group rickettsiosis in Israel during 2010-2019, we identified 42 cases, of which 36 were autochthonous. The most prevalent species was the Rickettsia conorii Israeli tick typhus strain (n = 33, 79%); infection with this species necessitated intensive care for 52% of patients and was associated with a 30% fatality rate. A history of tick bite was rare, found for only 5% of patients; eschar was found in 12%; and leukocytosis was more common than leukopenia. Most (72%) patients resided along the Mediterranean shoreline. For 3 patients, a new Rickettsia variant was identified and had been acquired in eastern, mountainous parts of Israel. One patient had prolonged fever before admission and clinical signs resembling tickborne lymphadenopathy. Our findings suggest that a broad range of Rickettsia species cause spotted fever group rickettsiosis in Israel.

Francisella-Like Endosymbionts and Rickettsia Species in Local and Imported Hyalomma Ticks

Hyalomma ticks (Acari: Ixodidae) are hosts for Francisella-like endosymbionts (FLE) and may serve as vectors of zoonotic disease agents. This study aimed to provide an initial characterization of the interaction between Hyalomma and FLE and to determine the prevalence of pathogenic Rickettsia in these ticks. Hyalomma marginatum, Hyalomma rufipes, Hyalommadromedarii, Hyalommaaegyptium, and Hyalommaexcavatum ticks, identified morphologically and molecularly, were collected from different hosts and locations representing the distribution of the genus Hyalomma in Israel, as well as from migratory birds. A high prevalence of FLE was found in all Hyalomma species (90.6%), as well as efficient maternal transmission of FLE (91.8%), and the localization of FLE in Malpighian tubules, ovaries, and salivary glands in H. marginatum Furthermore, we demonstrated strong cophylogeny between FLE and their host species. Contrary to FLE, the prevalence of Rickettsia ranged from 2.4% to 81.3% and was significantly different between Hyalomma species, with a higher prevalence in ticks collected from migratory birds. Using ompA gene sequences, most of the Rickettsia spp. were similar to Rickettsiaaeschlimannii, while a few were similar to Rickettsiaafricae of the spotted fever group (SFG). Given their zoonotic importance, 249 ticks were tested for Crimean Congo hemorrhagic fever virus infection, and all were negative. The results imply that Hyalomma and FLE have obligatory symbiotic interactions, indicating a potential SFG Rickettsia zoonosis risk. A further understanding of the possible influence of FLE on Hyalomma development, as well as on its infection with Rickettsia pathogens, may lead to novel ways to control tick-borne zoonoses.IMPORTANCE This study shows that Francisella-like endosymbionts were ubiquitous in Hyalomma, were maternally transmitted, and cospeciated with their hosts. These findings imply that the interaction between FLE and Hyalomma is of an obligatory nature. It provides an example of an integrative taxonomy approach to simply differentiate among species infesting the same host and to identify nymphal and larval stages to be used in further studies. In addition, it shows the potential of imported Hyalomma ticks to serve as a vector for spotted fever group rickettsiae. The information gathered in this study can be further implemented in the development of symbiont-based disease control strategies for the benefit of human health.

Emerging Infections and Pertinent Infections Related to Travel for Patients with Primary Immunodeficiencies

In today's global economy and affordable vacation travel, it is increasingly important that visitors to another country and their physician be familiar with emerging infections, infections unique to a specific geographic region, and risks related to the process of travel. This is never more important than for patients with primary immunodeficiency disorders (PIDD). A recent review addressing common causes of fever in travelers provides important information for the general population Thwaites and Day (N Engl J Med 376:548-560, 2017). This review covers critical infectious and management concerns specifically related to travel for patients with PIDD. This review will discuss the context of the changing landscape of infections, highlight specific infections of concern, and profile distinct infection phenotypes in patients who are immune compromised. The organization of this review will address the environment driving emerging infections and several concerns unique to patients with PIDD. The first section addresses general considerations, the second section profiles specific infections organized according to mechanism of transmission, and the third section focuses on unique phenotypes and unique susceptibilities in patients with PIDDs. This review does not address most parasitic diseases. Reference tables provide easily accessible information on a broader range of infections than is described in the text.

Israeli Spotted Fever in Sicily. Description of two cases and minireview

Mediterranean spotted fever (MSF) is endemic in Italy, where Rickettsia conorii subsp. conorii was thought to be the only pathogenic rickettsia and Rhipicephalus sanguineus the vector and main reservoir. R. conorii subsp. israelensis, which belongs to the R. conorii complex, is the agent of Israeli spotted fever (ISF); apart from Israel, it has also been found in Italy (Sicily and Sardinia) and in different regions of Portugal. We describe here two severe cases of ISF which occurred in otherwise healthy Italian adults. Their characteristics are analyzed and discussed in the light of other 91 cases found through a systematic review of international literature.

Genetic characterization of spotted fever group rickettsiae in questing ixodid ticks collected in Israel and environmental risk factors for their infection

This study aimed to genetically characterize spotted fever group rickettsiae (SFGR) in questing ixodid ticks from Israel and to identify risk factors associated with SFGR-positive ticks using molecular techniques and geographic information systems (GIS) analysis. 1039 ticks from the genus Rhipicephalus were collected during 2014. 109/1039 (10·49%) carried SFGR-DNA of either Rickettsia massiliae (95), 'Candidatus Rickettsia barbariae' (8) or Rickettsia conorii (6). Higher prevalence of SFGR was found in Rhipicephalus turanicus (18·00%) compared with Rhipicephalus sanguineus sensu lato (3·22%). Rickettsia massiliae was the most commonly detected species and the most widely disseminated throughout Israel (87·15% of all Rickettsia-positive ticks). GIS analysis revealed that Central and Northern coastal regions are at high risk for SFGR. The presence of ticks was significantly associated with normalized difference vegetation index and temperature variation over the course of the year. The presence of rickettsiae was significantly associated with brown type soils, higher land surface temperature and higher precipitation. The latter parameters may contribute to infection of the tick with SFGR. Health care professionals should be aware of the possible exposure of local communities and travellers to R. massillae. Molecular and geographical information can help professionals to identify areas that are susceptible to SFGR-infected ticks.

Rickettsia africae and Candidatus Rickettsia barbariae in ticks in Israel

DNA of several spotted fever group rickettsiae was found in ticks in Israel. The findings include evidence for the existence of Rickettsia africae and Candidatus Rickettsia barbariae in ticks in Israel. The DNA of R. africae was detected in a Hyalomma detritum tick from a wild boar and DNA of C. Rickettsia barbariae was detected in Rhipicephalus turanicus and Rhipicephalus sanguineus collected from vegetation. The DNA of Rickettsia massiliae was found in Rh. sanguineus and Haemaphysalis erinacei, whereas DNA of Rickettsia sibirica mongolitimonae was detected in a Rhipicephalus (Boophilus) annulatus. Clinicians should be aware that diseases caused by a variety of rickettsiae previously thought to be present only in other countries outside of the Middle East may infect residents of Israel who have not necessarily traveled overseas. Furthermore, this study reveals again that the epidemiology of the spotted fever group rickettsiae may not only involve Rickettsia conorii but may include other rickettsiae.

Spotted fever group rickettsiae in ticks collected from wild animals in Israel

We report molecular evidence for the presence of spotted fever group rickettsiae (SFGR) in ticks collected from roe deer, addax, red foxes, and wild boars in Israel. Rickettsia aeschlimannii was detected in Hyalomma marginatum and Hyalomma detritum while Rickettsia massiliae was present in Rhipicephalus turanicus ticks. Furthermore, a novel uncultured SFGR was detected in Haemaphysalis adleri and Haemaphysalis parva ticks from golden jackals. The pathogenicity of the novel SFGR for humans is unknown; however, the presence of multiple SFGR agents should be considered when serological surveillance data from Israel are interpreted because of significant antigenic cross-reactivity among Rickettsia. The epidemiology and ecology of SFGR in Israel appear to be more complicated than was previously believed.

Spotted fever rickettsiosis infection in a traveler from Sri Lanka

A case is reported of travel-acquired tick-borne spotted fever rickettsiosis from Sri Lanka. Little is known about rickettsial disease in Sri Lanka and this case may be the first documented instance of travel-acquired spotted fever group rickettsiosis from that origin.

Fatal Rickettsia conorii subsp. israelensis infection, Israel

Underdiagnosis of fatal spotted fever may be attributed to nonspecific clinical features and insensitive acute-phase serologic studies. We describe the importance of molecular and immunohistochemical methods in establishing the postmortem diagnosis of locally acquired Israeli spotted fever due to Rickettsia conorii subsp. israelensis in a traveler returning to Israel from India.

Clusters of Mediterranean Spotted Fever in Israel

Mediterranean spotted fever (MSF) usually occurs as sporadic cases. We report five clusters of MSF in Israel. Each cluster consisted of two to three patients. In two clusters, one patient died while the other recovered. In the other three clusters the patients presented with a benign course of the disease. The diagnosis of MSF in the fatal cases was confirmed by nested-polymerase chain reaction (PCR) tests performed on samples obtained from internal organs. Rickettsial DNA was also found in a tick obtained from a dog owned by one of the patients. MSF was diagnosed in the recovered patients by serology. The diagnosis of MSF fever in one family member should raise the awareness to the possibility of other cases in the vicinity.

[Neurological feature of Mediterranean spotted fever: a study of four cases]

BACKGROUND

Rickettsia conorii is the etiologic agent of Mediterranean spotted fever that is endemic in Mediterranean.

EXEGESIS

We report four cases of serious form of Mediterranean spotted fever with neurological feature. Two of them 56 and 62 years old had meningoencephalitis. Two others had cerebellitis, they are aged 43 and 56. The course has been favourable with ciprofloxacin.

CONCLUSION

It is a benign well-known illness in spite of apparition of severe visceral complications, which can drag the death in 2.5% of cases. Neurological feature is more frequent and present in 28% of cases. Precocious treatment prevents this unfavourable evolution.

Mediterranean spotted fever in Portugal: risk factors for fatal outcome in 105 hospitalized patients

Mediterranean spotted fever (MSF) is the most important tick-borne disease in Portugal. It is a notifiable disease and during 1989-2000 the annual incidence rate in Portugal was 9.8/10(5) inhabitants. Although recognized as a benign acute disease and treated mainly with ambulatory procedures, some cases are severe and fatalities have increased in the last few years. In 1997, MSF mortality became more evident in Beja, a Portuguese southern district, with a case fatality rate of 32.3% in hospitalized patients. Analysis of 55 variables regarding epidemiologic, clinical, laboratory, and therapeutic data of fatal and nonfatal MSF cases were compared to identify risk factors in 105 patients hospitalized in Beja District Hospital, between 1994 and 1998. It was statistically significant that the patients dying in 1997 were younger than those in other years. The risk of dying is statistically significant in those who presented with diabetes, vomiting, dehydration, and uremia. The interval between the onset of symptoms to administration of anti-rickettsial therapy was the same for all patients. Therapy delay, reported by some authors to be associated with mortality of MSF, was not a risk factor in our study. The patients who died in 1997 died faster than those in other years. The variables studied could not explain the higher mortality rates observed in our study. Although one may speculate that the pathogenic strain of Israeli tick typhus, isolated in 1997, could be responsible for this increase of fatality rate, inherited patient factors might also be strongly associated with mortality.

Mediterranean spotted fever during pregnancy: case presentation and literature review

Mediterranean spotted fever (MSF) is caused by Rickettsia conorii, an obligate intracellular parasite of eukaryotic cells. Although, usually this disease has a benign course, a rapidly fatal outcome can occur even in young healthy adults. We describe a case of a 40-year-old Bedouin woman gravida 11, para 10, who was admitted at 36 weeks gestation with this rickettsial disease. During pregnancy, the treatment of choice for Mediterranean spotted fever is chloramphenicol, but it seems that Azithromycin could be another possible option.