First report of human granulocytic ehrlichiosis from southern Europe (Spain).

Emerging Infectious Diseases Vol. 6, No. 4, July–August 2000 430 During a survey of parasitic helminths of wild vertebrates from Tres Palos Lagoon, in Guerrero, Mexico, we found Gnathostoma sp. advanced third-stage larvae (AdvL3) in the skeletal muscle of several fish species. Fish were caught from March to August 1999 in Tres Palos Lagoon (16° 41' to 16° 50'N and 99° 37' to 99° 47'W), Acapulco Municipality, 25 km south of Acapulco Bay (5). Fish muscle was ground individually, compressed between glass plates, and examined with a magnifying glass and a lamp. The infection was characterized as by Margolis et al. (6). Of nine fish species examined, five were positive for Gnathostoma AdvL3: Eleotridae: Dormitator latifrons (“popoyote,” n = 83), Gobiomorus maculatus (“guavina,” n = 66), Eleotris pictus (“alahuate,” n = 22); Cichlidae: Cichlasoma trimaculatum (“charra,” n = 62), and Ariidae: Cathorops caerulescens (“cuatete,” n = 62). The highest prevalence and mean abundance values (number of larvae per fish) were found in E. pictus (31.81%, 0.82 ± 1.99); in the other host species values were <7.22 and 0.072 ± 0.26, respectively. E. pictus mean abundance values differed significantly from those of the other host species (nonparametric KruskalWallis test, H = 27.125, 4 g.l., n = 337, p <0.0). The intermediate host transmitting the infection to humans in Mexico had previously been identified only in the Rio Papaloapan Basin, in Veracruz and Oaxaca (7,8). The presence of Gnathostoma AdvL3 in the muscle of fish species frequently eaten by humans in Acapulco suggests that these fish may have been the main source of infection in the 98 recorded cases of gnathostomosis (3,4). The popularity of “ceviche” (raw fish marinated in lime juice), prepared with the most commonly caught fish (including the three species of eleotrids studied), strongly supports this possibility. The identification of the source of human infection allows local health authorities to implement public information campaigns about the risk of eating raw or undercooked fish (in the form of sushi or ceviche) in this region. After this initial step in the study of this parasitic disease, the worm species must be accurately identified. In addition, understanding the parasite’s life cycle is important for control of a parasitic disease. Acknowledgments We thank F. Bertoni, E. Martínez, C. Castilla, A. Monet, E. Cabrera, and B. Mendoza for their help in field collections.

During a survey of parasitic helminths of wild vertebrates from Tres Palos Lagoon, in Guerrero, Mexico, we found Gnathostoma sp. advanced third-stage larvae (AdvL 3 ) in the skeletal muscle of several fish species. Fish were caught from March to August 1999 in Tres Palos Lagoon (16° 41' to 16° 50'N and 99° 37' to 99° 47'W), Acapulco Municipality, 25 km south of Acapulco Bay (5). Fish muscle was ground individually, compressed between glass plates, and examined with a magnifying glass and a lamp. The infection was characterized as by Margolis et al. (6).
The intermediate host transmitting the infection to humans in Mexico had previously been identified only in the Rio Papaloapan Basin, in Veracruz and Oaxaca (7,8). The presence of Gnathostoma AdvL 3 in the muscle of fish species frequently eaten by humans in Acapulco suggests that these fish may have been the main source of infection in the 98 recorded cases of gnathostomosis (3,4). The popularity of "ceviche" (raw fish marinated in lime juice), prepared with the most commonly caught fish (including the three species of eleotrids studied), strongly supports this possibility. The identification of the source of human infection allows local health authorities to implement public information campaigns about the risk of eating raw or undercooked fish (in the form of sushi or ceviche) in this region. After this initial step in the study of this parasitic disease, the worm species must be accurately identified. In addition, understanding the parasite's life cycle is important for control of a parasitic disease.

First Report of Human Granulocytic Ehrlichiosis from Southern Europe (Spain)
To the Editor: Human granulocytic ehrlichiosis (HGE) is a tickborne zoonosis described in the United States several years ago (1) and in Europe recently (2). Several hundred cases have been reported in the United States (3). In Europe, nine cases have been reported, six in Slovenia (2,(4)(5)(6), and three in Sweden (I. Eliasson, http:\\www.healthnet.org/programs/promed.html). We report a serologically confirmed case of HGE in La Rioja, a Lyme disease-endemic area in northern Spain (7)(8)(9).
On August 7, 1999, a 16-year-old man from La Rioja, who had been bitten by a tick 15 days before, was seen in an emergency room and treated with 100 mg of doxycycline twice a day. On August 9, he was hospitalized with a 3-day history of malaise, myalgias, headache, and fever (39ºC). The fever abated in the next 36 hours. The patient had not noticed any signs of inflammation or skin rash, and no signs of neurologic injury were evident. He had abdominal pain when the liver was palpated. Chest radiographs were normal, and abdominal ultrasonography showed no abnormalities. Laboratory studies showed a level leukocyte count (3, ; Coxiella burnetti (IFA); Ehrlichia chaffeensis (IFA); the agent of HGE (IFA); and hepatitis A, B, and C viruses (ELISA); and indicated immunity for Epstein-Barr virus. Four weeks later, the aminotransferase levels were normal, and the patient was asymptomatic. A new serum determination showed an HGE antibody titer of 1:64 (HGE IFA IgG MRL Diagnostics, California, USA); the serum tested negative for the other microorganisms tested, including with a new test for E. chaffeensis. Another serum sample from the patient taken 8 weeks later showed a titer of 1:256 to the HGE agent. An EDTA-treated sample of whole blood obtained from the patient on day 4 after start of doxycycline treatment was negative for the E. phagocytophila genogroup by polymerase chain reaction (PCR). We used a set of primers based on the published sequence of the 16s rNA of E. phagocytophila (E1: 5'-GGC ATG TAG GCG GTT CGC TAA GTT -3' and E2: 5'-CCC CAC ATT CAG CAC TCA TCG TTT A -3') (7). Multiple water samples and a positive blood sample from an experimentally infected lamb were used as controls for PCR amplicon contamination. Doxycycline was administered for 14 days, and the patient's clinical and laboratory abnormalities resolved.
Many tickborne diseases are present in La Rioja. The prevalence of E. phagocytophila genogroup in the tick Ixodes ricinus is high (24.1% of nymphs, determined by PCR) in La Rioja, and evidence of HGE infection in patients at risk has been reported (10,11). This patient's history of previous tick bite, flulike symptoms, seroconversion to HGE agent, aminotransferase elevation, and response to doxycycline suggest the diagnosis of HGE. As in other reported cases in Europe, no morulae suggestive of Ehrlichia infection in the acute phase were visible, the clinical manifestations were moderate, and the fever abated quickly with treatment. Also, as in other cases, the negative PCR result can be explained by the prior treatment with doxycycline. José A. Oteo,* José R. Blanco,* Victor Martínez de Artola,* and Valvanera Ibarra* *Hospital de La Rioja, Logroño, Spain