675

Salmonella in poultry SIR,-As Professor Nurmi and his colleagues indicate (Jan 12, p 118) there is now ample evidence that the competitive exclusion (CE) technique has an important part to play in the reduction of silent carriage of food-poisoning salmonellae in poultry. The advantages of CE include the rapidity with which protection against salmonellae becomes evident (within a few hours of administering the normal microflora) and the broad antiserovar spectrum of activity obtained. In the many studies on this topic, newly hatched chicks have been protected against at least twenty different Salmonella serovars, including the organisms of greatest concern, S enteritidis and S typhimurium.1 The Finnish (and Swedish) experience shows that both the frequency of flock infection and salmonella contamination of processed carcasses can be greatly reduced and maintained at a low level with CE treatment. Other work suggests that any worthwhile control of cross-contamination in the processing plant can only be achieved when flock infection is suitably reducedThe need for a comprehensive and coordinated programme for salmonella control should be recognised, together with measures taken during rearing and processing, and such a programme should be implemented within the UK industry as soon as possible. The prospects for success are greatly assisted by the fact that a commercial CE product (’Broilact’, Orion Corporation Farmos) is now available in the UK. If this programme is carried out we see no reason why salmonella contamination of UK poultry meat with any serovar should be any higher than that produced in Finland-ie, well below 5% of carcasses contaminated with less than ten organisms per carcass. Orion Corporation Farmos,

Patient 1, the first patient seen, had had symptoms for over 15 years that sometimes woke her up at night with a need to defaecate. She had been working all this time at the routine parasitology

laboratory, Roslagstull Hospital. Her stools had been repeatedly checked for pathogenic parasites but only large numbers of Ent coli had been found. Indeed these amoebae were so typical that they had been used for teaching purposes during diploma courses in tropical medicine at the Karolinska Institute. She was given diloxanide furoate and the intestinal symptoms disappeared, along with the amoebae. Her stools were checked for more than 8 weeks during and after treatment and amoebae did not reappear. She has remained well, without any gastrointestinal symptoms, for 2 years. The other patient with severe symptoms (patient 2) had loose stools and stomach pain which had led to radiological examination of the colon and sigmoidoscopy. All ten patients had had their symptoms for a long time. Typical complaints were loose, but not watery, stools without blood or mucus, flatulence, and sometimes colicky pain. Ent coli should be borne in mind with patients who have diarrhoeal disease. Whether the parasites themselves or a factor associated with them cause disease remains to be established. at 1 year

Department of Infectious Diseases, Karolinska Institutet,

Roslagstull Hospital, S-114 89 Stockholm, Sweden, and Department of Immunology, University of Stockholm

Lack of association between circulating HCV-RNA and anti-HCV positivity in

primary biliary cirrhosis

River House,

Bridge, Canterbury, Kent CT4 5LA, UK

NORMAN G. FOWLER

SIR,-The specificity of the C100-3 ELISA test for hepatitis C virus

University of Bristol, School of Veterinary Science, Langford House, Langford,

GEOFFREY C. MEAD

Bristol

MATS WAHLGREN

1. Mead GC, Impey CS The present status of me Nurmi concept for reducing carriage of food poisoning salmonellae and other pathogens in live poultry. In: Smulders FJM, ed. Elimination of pathogenic organisms from meat and poultry. Amsterdam: Elsevier, 1987. 57-77. 2. Prucha JS, Hollingsworth JM, James WO. The application of HACCP to poultry inspection—a status report of a feasibility study. (Proceedings of the 10th International Symposium of the World Association of Veterinary Food Hygienists, Stockholm, 1989). 201-05.

Entamoeba coli as cause of diarrhoea? SIR,-Entamoeba coli, unlike Ent histolytica, is not thought to intestinal disease, and textbooks refer to Ent coli as a harmless commensal of the intestinal tract. However, I have seen eight patients with Ent coli and mild persistent diarrhoea and two patients with Ent coli, persistent diarrhoea, and more severe symptoms: cause

antibody (anti-HCV) has been questioned.l-4 Unexpectedly high prevalence rates of anti-HCV have been found in autoimmune chronic liver disease,s and figures as high as 42% have been reported for primary biliary cirrhosis (PBC).1,6-9 However, high concentrations of serum immunoglobulins could interfere with the assay,1,6 and no data about circulating HCV-RNA, a true marker for infection, are available. We tested serum samples for anti-HCV collected from 106 consecutive patients with PBC who attended our centre from January to December, 1990. Of these, 88 patients had been followed for a median of 32 months (range 2-125) and samples from their first visit were also available. All samples had been frozen at - 20°C until tested by conventional ELISA (’Raritan’, Ortho Diagnostics, New Jersey, USA). Positive samples (optical density [OD] 0-459) were retested in duplicate, and then with the recombinant immunoblot assay (RIBA).3 To detect the HCV genome, RNA was extracted from ELISA-positive samples obtained in 1990, reversetranscribed, and amplified by the polymerase chain reaction (PCR) with primers of the non-structural region. By ELISA, 12 of 106 (11 %) patients were positive for anti-HCV (mean OD [SD] 1-7 the compared with a 68% prevalence (2-7 [0’7]) in a series of 135 patients with a clinical diagnosis of chronic non-A, non-B hepatitis (NANBH) followed by us and tested by the same method. We found no significant differences between PBC patients with and without anti-HCV with respect to age, presence of cirrhosis, or serum bilirubin. Serum IgG values were significantly higher in the anti-HCV-positive group (2750 [782] vs 1691 [524] mg/dl, p < 0-00 1, Mann-Whitney test), and the correlation between OD values and serum IgG concentrations was r 0-422 (p < 0-001). =

All were treated with diloxanide furoate (’Furamide’) 500 mg three times daily for 10 days and the amoebae and the intestinal symptoms disappeared. Before a patient was included in the study stools were repeatedly checked for other protozoa, helminths, or pathogenic parasites (light microscopy), for pathogenic bacteria (aerobic culture), for pathogenic viruses (electronmicroscopy), and for composition of anaerobic flora. No patient had an abnormal faecal flora or pathogens other than Ent coli in stools. Serum IgA levels and white cell counts were normal. Stools were checked weekly for 4 weeks after diloxanide treatment had started, and the patients returned for physical examination 1 month after treatment.

PCR AND RIBA TEST IN RELATION TO ELISA OD VALUES

676

Of the 88

patients who were being regularly followed, 11 (13%) anti-HCV positive by ELISA (OD 1.4 [1’0]) at the initial visit. 2 of these were ELI SA negative in 1990, whereas 1 patient, who was initially negative, had become ELISA positive by 1990. The latter had no identifiable source of infection. 3 of these ELISA-positive samples were reactive by RIBA, 2 were indeterminate (1 RIBA C100-3 reactive, 1 RIBA 5-1-1 reactive), and 6 were non-reactive. This corresponds to about a 3% prevalence of anti-HCV positivity for the group as a whole. For 7 of the 11 patients ELISA-positive in 1990, serum was available for HCV RNA determination. None had detectable HCV-RNA. The table shows ELISA OD values to RIBA and PCR data for these 7 patients. We conclude that the frequency of apparent anti-HCV positivity in Italian patients with PBC is somewhat higher than in the general population.10 However, since none of the patients with PBC tested by PCR, unlike those with autoimmune chronic active hepatitis5 had detectable HCV-RNA in serum, it is unlikely that HCV plays a part in the pathogenesis of PBC. were

Istituto di Scienze Biomediche, Ospedale S. Paolo, 20142 Milan, Italy

E. BERTOLINI P. ZERMIANI P. M. BATTEZZATI S. BRUNO

Division of Gastroenterology, University of Modena, Modena

E. VILLA F. MANENTI

Blood Transfusion Centre,

Ospedale S Paolo, Milan

F. MARELLI G. A. MORONI

Department of Medicine, Ospedale S. Paolo, Milan

M. ZUIN M. PODDA

Department of Internal Medicine,

1. McFarlane IG, Smith HM, Johnson PJ, Bray GP, Vergani D, Williams R. Hepatitis C virus antibodies in chronic active hepatitis: pathogenic factor or false-positive result? Lancet 1990; 335: 754-57. 2. Theilmann L, Blazek M, Goeser T, Gmelin K, Kommerell B, Fiehn W. False-positive anti-HCV tests in rheumatoid arthritis. Lancet 1990; 335: 1346. 3. Weiner AJ, Truett MA, Rosenblatt J, et al. HCV testing in low-risk population. Lancet 1990; 336: 695. 4. Wong DC, Diwan AR, Rosen L, et al. Non-specificity of anti-HCV test for seroepidemiological analysis. Lancet 1990; 336: 750-51. 5. Magrin S, Craxi A, Fabiano C, et al. Are autoimmune chronic active hepatitis (CAH) and HCV-infection related diseases? J Hepatol (in press). 6. Housset C, Hirschauer C, Courouce AM, Calvo A, Degos F, Benhamou JP. High prevalence of false positive anti HCV tests in primary biliary cirrhosis. J Hepatol 1990; 11: S30. 7. Fusconi M, Lenzi M, Ballardini G, et al. Anti-HCV testing in autoimmune hepatitis

and primary biliary cirrhosis. Lancet 1990; 336: 823. 8. Chiaramonte M, Floreani A, Giacomini A, et al. Anti-HCV in primary biliary cirrhosis. Gut 1990; 31: A626. 9. Schrumpf E, Elgjo K, Fausa O, Haukenes G, Rollag H. The significance of anti-HCV antibodies measured in chronic liver disease. J Hepatol 1990; 11: S111 10. Sirchia G, Bellobuono A, Giovannetti A, Marconi M. Antibodies to hepatitis C virus in Italian blood donors. Lancet 1989; ii: 797.

Horizontal transmission of

hepatitis

B virus

SiR,—Dr Gill and colleagues (Jan 26, p 247) highlight their findings of high prevalence of hepatitis B markers in former far eastern prisoners-of-war (POWs). We too have done such a study, examining specimens taken from all POWs who presented to Royal Air Force hospitals for health screening during 1990. The patients had been held in various geographical locations throughout south-east Asia for variable periods of time. Our findings agree with those of Gill et al,l showing a similar rate of past infection with hepatitis B (44% of 107). However, 4 (3-7%) of our study group proved to be carriers of HBsAg, whereas none was in Gill and colleagues’ group. Investigation of the prevalence of hepatitis B infection in the British Armed Forces (unpublished data) indicate that past infection with and carriage of HBsAg is very rare, being even lower than that cited for selected UK populationsThis may reflect the smaller "at risk" groups within the military (ie, intravenous drug abusers, homosexuals), and a different ethnic profile, from that of the UK in general. From a practical viewpoint this means that the POW patients form a major group of patients within military hospitals in this country that is likely to pose a risk for hepatitis B transmission. Although they may be a small proportion of such

patients elsewhere, their importance in respect of infection control should not be forgotten. Pathology and Tropical Medicine, Halton, Aylesbury, Bucks HP22 5PG, UK RAF Institute of

A. D. GREEN

S. J. HARBOUR

GV, Bell DR, Vamdervelde EM. Horizontal transmission of hepatitis B virus amongst British 2nd World War soldiers in South-East Asia Postgrad Med J 1991, 67: 39-41. 2. Tedder RS, Cameron CH, Barbara JAJ, Howell D Viral hepatitis markers in blood donors with history of jaundice. Lancet 1980; i: 595-96. 1. Gill

Rickettsia conorii isolated from ticks introduced to northern France by a dog SiR,—A 53-year-old man presented in October, 1989,2 months after his return from a stay on the French Riviera, with a severe form of Mediterranean spotted fever. He had a widespread rash with black eschar on the anterior chest, pneumonia, lymphocytic meningitis, nephritis, hepatitis, and conjunctival injection. Serological tests, with immunofluorescence techniques, were positive with titres of 10 240 for IgG and 640 for IgM. After treatment with ofloxacin for 3 weeks he was cured. The time that had elapsed between the end of his stay on the French Riviera and the onset of clinical signs was too long for the infection to have been acquired while he was in that endemic area.’1 In November, 1989, the patient’s dogs, which had been on the French Riviera during that summer, were found to be seropositive for Rickettsia conorii (IgG titre 2560). In May, 1990, three ticks (Rhipicephalus sanguineus) were found on the dogs. After culture on primary chicken embryo cells and inoculation in guineapigs, R conorii was identified (Dr M. Tibon, Rickettsia Laboratory, Institute Pasteur, Paris). This observation confirms the possibility of Mediterranean spotted fever being "exported" from an endemic area (here southeastern France) via dogs carrying tick-bome R conorii.2,3 The mild 1989-90 winter and early spring probably helped dog ticks to survive.4-6 This form of Mediterranean spotted fever, with a seemingly uncharacteristic incubation period, may mislead the physician and delay the onset of specific treatment. When Mediterranean spotted fever is suspected, an unusual incubation period (more than 15 days) should not exclude the diagnosis.

Department of Infectious Diseases, University of Lille, Centre Hospitalier de Tourcoing 59208 Tourcoing, France

E. SENNEVILLE F. AJANA P. LECOCQ

C. CHIDIAC Y. MOUTON

1. Font-Creus B, Bella-Cueto F, Espero-Arenas E, et al Mediterranean spotted fever, a cooperative study of 227 cases. Rev Infect Dis 1985; 7: 635-42. 2. Lambert M, Dugernier T, Bigaignon G, Rahier J, Piot P. Mediterranean spotted fever in Belgium. Lancet 1984; ii: 1038 3. Peter O, Burgdorfer W, Aeschlimann A, Cuatelannat P. Rickettsia conoru isolated from Rhipicephalus sanguineus introduced m Switzerland on a pet dog. Z Parasit 1984. 70: 265-70 4. Esero-Arenas E, Font-Creus B, Bella-Cueto F, Segura-Porta F Climatic factors in resurgence of Mediteranean spotted fever. Lancet 1986; i 1333 5. Brouqui P, Toga B, Raoult D. La fièvre boutonneuse Méditerranéenne en 1988 Méd Mal Infect 1988; 6/7: 323-28. 6. Segura-Porta F, Font-Creus B. Resurgence of Mediterranean spotted fever in Spain Lancet 1982; ii. 280.

Q fever: from deer to

dog to man

SIR,-Cattle, sheep, and goats are the main reservoirs of Coxiella burnetii in man.1 Human infection commonly takes place when an infected animal gives birth, since high concentrations of the organism are found in the products of conception.2We now report the first outbreak of Q fever after exposure to a deer and an infected pregnant dog. In late November, 1989,7 members (A-G) of a family from New Brunswick became ill with headache, fever, myalgia, fatigue, sweats, and a mild non-productive cough. 6 had multiple small round opacities on chest radiography. 6 had a greater than four-fold rise in phase II antibody titre to C burnetii antigen with the indirect immunofluorescence test (IFA). The seventh family member had a

Lack of association between circulating HCV-RNA and anti-HCV positivity in primary biliary cirrhosis.

675 Salmonella in poultry SIR,-As Professor Nurmi and his colleagues indicate (Jan 12, p 118) there is now ample evidence that the competitive exclus...
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