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Knowledge about the duration of digestive carriage of ESBL- and carbapenemase-producing Enterobacteriaceae is an essential information, impacting clinical decisions (empiric treatment for known carriers) and infection control measures (preemptive precautions, sequential screening). Ten to 50% carriers are still colonized after one year, but these numbers might be overestimated. Use of genomic typing is required to distinguish endogenous long-term carriage from exogenous recolonization events. Median length of colonization appears to range between 0,5 and 13 months for E-ESBL and 0,7 to 10 months for CPE. We performed a narrative review of the literature on this topic. We finally suggest a few future perspectives., Competing Interests: Les auteurs n’ont déclaré aucun conflit d’intérêts en relation avec cet article.

Introduction: hepatitis C is an infection which can be passed from mother to child. The purpose of this study was to investigate the prevalence of colonization by anti-HCV antibodies in pregnant women living in Cotonou and to identify factors associated with it., Methods: we conducted a cross-sectional study of 253 pregnant women admitted for prenatal care in four major maternity hospitals in Cotonou (Benin) from 01/06/2018 to 01/09/2018. Anti-HCV antibodies were detected using rapid diagnostic tests. A venous blood sample was collected from pregnant women tested positive for anti-HCV before confirmatory serological tests and screening tests for gestational diabetes., Results: the prevalence of anti-HCV antibodies was 1.2% (3/253 pregnant women). Factors associated with HCV carriage couldn't be identified given the low number of positive cases. However, pregnant women who were carriers of hepatitis C antibodies had higher mean age (32 ± 3) compared to the remainder of the population (29.58 ± 5.5). Potential risk factors for HCV infection were scarifications, piercing, tattooing, sharing of manicure equipment, a history of surgery and blood transfusions. The prevalence of gestational diabetes in our study population was 7.9% (20/253). No association was found between gestational diabetes and hepatitis C., Conclusion: the prevalence of anti-HCV antibodies in pregnant women living in Cotonou was low. A national-level study is needed to identify factors associated with this infection., Competing Interests: Les auteurs ne déclarent aucun conflit d´intérêt., (Copyright: Moufalilou Aboubakar et al.)

The Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC) organizes annual workshops in the attempt to harmonize clinical practices among different francophone transplantation centers. Here we report our recommendations regarding detection of the multidrug-resistant bacteria in hematology., (Copyright © 2020 Société Française du Cancer. Published by Elsevier Masson SAS. All rights reserved.)

Malaria is a potentially life-threatening tropical infectious disease caused by a parasite that infects erythrocytes. Its transmission is vectorial, but the transfusion of infected red blood cells can cause a delicate diagnosis of transmitted malaria. Prevention is based on the selection of donors at risk by the search for antibodies reflecting past infection, in the absence of a sufficiently sensitive parasite detection technique to prevent all risks. Recent cases of transfusion malaria have reiterated that this preventive measure does not allow screening of all asymptomatic carriers., (Copyright © 2019 Société française de transfusion sanguine (SFTS). Published by Elsevier Masson SAS. All rights reserved.)

To assess the hepatitis B virus (HBV) serologic status of hospital health care personnel in Lome. From June 1 to August 31, 2007, 100 workers vaccinated against HBV and 50 unvaccinated workers participated in this comparative cross-sectional study. The data studied were: age, sex, vaccination status, history of accidental exposure to blood, and enzyme-linked immunoassay results for HBs antigen (Ag), total anti-HBc antibodies (Ab), and anti-HBs Ab. Vaccinated subjects had a mean age of 33.2 ± 8.2 years and unvaccinated subjects of 35.2 ± 9.6 years; their respective sex ratios (M:W) were 2:1 and 3:1. Protective levels (>10 IU/L) of anti-HBs Ab were found in 78% (n = 78) of vaccinated subjects compared with 44% (n = 22) of those unvaccinated. HBs Ag was found in 36% (n = 36) of vaccinated and 56% (n = 28) of unvaccinated subjects. Of subjects previously accidentally exposed to blood, 67% (n = 35) had HBs Ag compared with 30% (n = 29) of those subjects without such exposure. This study has proved the high prevalence of HBs Ag carrier status among health care workers in Lome and confirms the importance of vaccination against HBV.

Aim of the Study: Evaluate the feasibility of Staphylococcus aureus nasal colonization and bacteriuria screening in outpatients before realizing a decolonization treatment in S. aureus carriers and a bacteriuria treatment before hospitalization., Methods: All patients undergoing hip, knee or back surgery in which prosthesis were implanted between October 2007 until the end of June 2008 were included. Microbiological studies were performed before hospitalization. Notice for S. aureus decolonization regimen was delivered to each patient and to the general practitioner only if the patient had nasal carriage., Results: Only 91.2% (240/263) of patients had microbiological results. Prevalence of S. aureus colonization was 21.4% (48 positives/224). Three patients were colonized with methicillin-resistant staphylococci. Decolonization regimen was applied before surgery to 70.8% (n=34) of the colonized patients. Among the patients, 8.9% (20/225) had bacteriuria, Escherichia coli being the most frequent micro-organism (n=16)., Conclusion: Preoperative search and management of S. aureus colonization and of bacteriuria in outpatients is possible. Monitoring record must be performed by a member of the hospital staff., (Copyright 2009 Elsevier Masson SAS. All rights reserved.)

Objective: To evaluate the potential interest of screening of Pseudomonas aeruginosa on admission and during hospitalisation in intensive care units patients., Method: A retrospective study was carried out in two adult ICU of the University-Hospital of Besançon in 2007. P. aeruginosa screening was performed on admission and once a week during ICU stay. Clinical samples positive with P. aeruginosa were collected., Results: Among the 754 patients included, 146 had a screening sample positive giving an average incidence of 19.4 per 100 patients. Thirty-five were imported and 111 ICU-acquired. Sixty-one patients had at least one positive clinical sample, that is an incidence 8.1 cases per 100 admitted patients. Sensibility, specificity, positive and negative predictive values of screening as an indicator of subsequent infection were 54.1%, 86.9%, 26.6% and 95.6%, respectively., Conclusion: Screening samples are necessary to assess P. aeruginosa endemicity in intensive care units. The high negative predictive value of screening suggests that use of specifics anti-Pseudomonas antimicrobials could be reduced. However, the benefit of this strategy remains to be evaluated., (Copyright 2009 Elsevier Masson SAS. All rights reserved.)

Objectives: To compare and evaluate the new chromogenic StrepB Select (BioRad) medium to the Granada (bioMérieux) and Columbia horse blood agar plates (CH-BAP) for screening of Group B Streptococcus (GBS) vaginal colonization in pregnant women., Methods: One hundred and ninety vaginal swabs were processed and the three media inoculated. All plates were examined after 18-24h incubation at 37 degrees C and reincubated for an additional 24h. All suspected colonies were identified as GBS by using a commercial Lancefield group-specific latex agglutination test., Results: GBS were isolated in 32 samples (16.8%) by at least one medium. After 24h of incubation, GBS were recovered on CH-BAP in 16 samples (50%) compared to 28 (87.5%) for StrepB Select, and 27 (84.5%) for Granada. After 48h of incubation, 30 (93.7%) out of the 32 GBS vaginal carriers were positive with CH-BAP, StrepB Select and Granada. Other streptococcal and enterococcal species gave GBS-like colonies on StrepB Select medium implying the use of other tests to confirm GBS identification. We demonstrated that direct agglutination of GBS isolated all media with Pastorex StrepB accurately identified GBS. The two StrepB Select false-negative results corresponded to a very low colonisation rate. Two Granada false-negative results corresponded to non-haemolytic and non-pigmented GBS strains which were correctly identified on StrepB Select. Both selective media inhibit the growth of associated saprophytic flora., Conclusion: The use of the new StrepB Select chromogenic medium in routine laboratories may therefore markedly facilitate the rapid and accurate detection of GBS in vaginal samples.

Objectives: In a bid to combat methicillin-resistant Staphylococcus aureus (MRSA) more efficiently in our department, we performed a study to 1) clarify the MRSA carriage rate in patients hospitalized in the department; 2) evaluate the rate of MRSA acquisition during hospitalization; 3) describe the MRSA carrier profile; 4) study the morbidity and mortality associated with MRSA., Patients and Methods: We conducted a three-month prospective study in all patients hospitalized for more than 24hours in the dermatology department of the Saint-Louis Hospital. Nasal swab cultures were performed on the day of admission, once a week thereafter and on the day of discharge. Clinical and epidemiological data were individually reviewed by means of a standardized questionnaire., Results: In 310 patients, the prevalence of nasal MRSA carriage at admission was 6.5%. During hospitalization, 1.9% of our patients became colonized with MRSA. MRSA carriers were significantly older than non-carriers and had been hospitalized more frequently over the previous 12 months, principally in intensive care or in intermediate or long-term care facilities, and erosive and/or ulcerated dermatitis was more common in this population. Of the 27 patients colonized with MRSA, only three had MRSA infections, and these were successfully treated with antibiotics., Discussion: The observed rate of MRSA carriage was close to that seen in intensive care units (7%). While systematic screening for MRSA in patients with erosive and/or ulcerated dermatitis would allow detection of twice as many cases of MRSA than the usual screening recommendations, this would be associated with little tangible benefit and high costs, and we therefore decided not to change the usual MRSA screening politic in our dermatology department.

Aim of the Study: To describe specific difficulties to control a glycopeptide-resistant Enterococcus (GRE) outbreak occurring in an intensive care unit (ICU) during a regional epidemy., Patients and Methods: Following identification of a GRE clinical isolate in ICU, systematic screening was performed on admission and then weekly, by anal swabs. GRE carriers were isolated according to two processes: first (week [W] 2-W8), cohorting of carriers in a dedicated sector of the ICU, with dedicated HCW; this required closing four of the 16 ICU beds. Second (W8-W29), a specific unit was created outside the ICU. VanA-genotypes and pulsed-field gel electrophoresis (PFGE) profiles were analyzed., Results: During the first outbreak period (102 rectal swabs), two patients were found colonized at admission: the index case transferred from Nancy hospital, carrier of the Nancy epidemy PFGE profile strain, and one patient from the haemodialysis unit, carrier of a GRE strain presenting a different PFGE profile called the Thionville strain. Seven patients were newly identified as GRE colonized (2 by the Nancy strain and 5 by the Thionville strain). Defective running of the ICU was noted. During the second period (442 samples), six ICU patients were found colonized, including four at admission. No other case was identified in 16 weeks. Outbreak extension to other hospital units was checked at W19. The Thionville strain was not found in other regional hospitals., Conclusion: ICUs concentrate GRE colonization risk. This study demonstrates interest of PFGE. These low virulence bacteria have few direct pathological consequences, but they cause organizational problems in ICUs.

We investigated the prevalence of bacterial and parasitic infections among workers in a pastry factory in North Lebanon in 2004. We found 39% of the workers (n = 196) had nasal carriage of Staphylococcus aureus. Resistance of S. aureus isolates was 98.7% to penicillin G, 24.7% to fusidic acid, 14.3% to pefloxacine and tetracycline, 11.7% to erythromycin, 6.5% to oxacillin and amoxicillin-clavulanate. Salmonella typhi was not found in any of the workers. Prevalence of intestinal parasites was 57.8% (n = 308). Amoebae comprised 72.5% (68.3% Entamoeba coli, 15.5% E. histolytica), followed by flagellates (18.0 %) (37.5% Dientamoeba fragilis, 31.3% Giardia lamblia) and nematodes (7.8%) (only Ascaris lumbricoides). The tuberculin test was positive in 16.3% of the workers (n = 301).

Introduction: False-negative findings of polymerase chain reaction (PCR) for genuine pertussis as well as the numerous atypical forms of whooping cough make it difficult to diagnose this disease in young babies., Methods: For two years, real-time PCR was performed to test for Bordetella pertussis in 86 infants younger than 6 months hospitalized for apnea or paroxysmal and/or vomiting cough and in 205 of their household contacts, whether or not they coughed., Results: Group 1 included 30 infants for whom PCR detected B. pertussis (25 of whom were also RSV+). PCR was also positive for at least one household contact in 25/30 families. This group included 16 babies with apnea and 12 who developed a whooping cough during follow-up. Group 2 comprised 12 infants whose PCR was negative while at least one household contact had positive results. Five of these infants had severe apnea and 6 developed a whooping cough. Group 3 included 44 infants (28 RSV +) for whom PCR was negative in the index case and in the household contacts: none developed a whooping cough during follow-up. Only 3 of the 54 positive household contacts had a paroxysmal cough or a typical whooping cough and 12 had no cough at all., Conclusion: Positive PCR in a household contact, symptomatic or not, is helpful for the diagnosis of atypical whooping cough in young infants.

Objective: To determine the rate and risk factors for group B streptococcus (GBS) colonization in term pregnancies., Patients and Methods: Vaginal and anal cultures were prospectively conducted in 294 parturient on admission for term vaginal delivery., Results: Thirty-eight (12.92%) parturient had positive GBS cultures. None of the studied risk factors (age, education status, nulliparity, previous obstetric problem, twin pregnancy and diabetes) was statistically predictive of maternal colonization. All the isolated GBS were sensitive to the penicillin G., Discussion and Conclusion: Systematic screening strategy of GBS close to the delivery on all pregnant women is desirable.

Presymptomatic testing is available since 15 years for Huntington disease and it is now possible for a number of other neurogenetic disorders, mostly neurodegenerative disorders. The possibility of determining the genetic status of an at-risk person for the disorder which run in his family raises questions because of the absence of preventive and curative treatments in most instances. In addition, being carrier does not tell you when the disease will start and how it will evolve, impairing the possibilities of planning the future. A pluridisciplinary approach to predictive testing with care before, during and after the test taking into account the medical, social and psychological aspects of the disease is good practice. At the present time, only a minority of at-risk individuals request presymptomatic testing and almost 50 % do not pursue until the results. The consequences of the test may be harmful, more frequently after an unfavorable than after a favorable result. Although the motivations and the outcome in terms of request for prenatal testing after a carrier result are different in Huntington's disease and spinocerebellar ataxias, our experience underlines the benefit of pluridisciplinary care and of time for decision taking. For other disorders like familial Alzheimer's disease, or familial Creutzfeldt-Jakob disease, the experience in presymptomatic testing is still limited but the situation seems similar to Huntington's disease because of the presence of dementia. It will be interesting to study the motivations and the outcome of the tests in disorders like autosomal dominant spastic paraplegias which usually do not reduce the life expectancy. Nevertheless, the overall situation might change greatly when efficient treatments will become available in these disorders.

The aim of this study was to determine the transfusion transmitted Virus (TTV) prevalence in three groups of population from Abidjan, Côte d'Ivoire. The A group contained 39 multitransfused patients, the B group contained 10 blood donors supposed to be healthy persons which have never been transfused and the group C contained 43 patients with chronic liver pathology. In this last group, 33 patients had HBV positive serology and the 10 others, HCV positive serology. We used PCR to investigate TTV in patients serum. Detection rates were comprised between 67% and 82%. This is the first study to provide information about the high portage of TTV in ivorian population.

The aim of this study was to evaluate the prevalence rate and the risk factors for the carriage of hepatitis B markers in pregnant women in Bobo Dioulasso, Burkina Faso. Out of 917 pregnant women recruited during antenatal care, 98 (10.7%) were HBs antigen positive. Among these ones, 18.2% carded HBe antigen, 66.7% antiHBe antibodies and 95.6% antiHBc antibodies. Two risk factors were identified: maternal age of 23 and 28 (RR = 2.33, chi2 =12.21, p = 0.005) and widowage (Fisher test RR = 6.43, p = 0.0016). This high prevalence of HBs antigen calls for systematic screening for hepatitis B during antenatal care along with an immunization policy toward women of reproductive age and newborns.

Aim: Because there are few adoptable children in France, parents, for the last 20 years, have turned to international adoption. Alerted by the generally poor health of these children, we paid particular attention to their health problems and especially to infection by hepatitis B virus (HBV)., Population and Methods: The 60 internationally-adopted children seen from June 1993 to June 1997 were included in this study. All had hemogram and serum iron dosage, and search for intestinal parasites and tuberculosis was performed in each child, as were HBs antigen and HBs antibody screening. When HBs antigen was positive, HBe antigen and antibodies, HBV DNA and hepatitis C and delta serology were also studied., Results: Six out of the 60 children were HBV chronic carriers. The six presented HBs antigen and five out of the six presented viral DNA. One child was co-infected with delta virus. Serum aminotransferase was normal in three children and increased in the three others., Discussion: Some internationally adopted children are exposed to chronic infection by HBV. This concerns children coming from countries known for the high frequency of the disease, but also children with long stay in Eastern European nurseries. Chronic HBV carriage puts the child, as well as the family and other children in institutions and/or schools at risk, thus necessitating preventive measures.

Hepatitis C virus (HCV) is the main etiologic factor of post-transfusional and sporadic hepatitis, called non-A non-B in the past. These infections are characterized by a very high number of chronic carriers always with a persistent viral increase, but often at a slow pace. The seriousness of liver disease differs from one individual to another, varying from an asymptomatic form with minor or no liver injuries, to cirrhosis and hepatocellular carcinoma. Physiopathological mechanisms involved in liver injuries are still poorly understood. The direct role of immune response and of possible genetic factors is still under study. This review aims at summing up the discovery of HCV, its structure, and its variability in the various genome regions in the same individual and from one individual to another. The different methods and techniques to analyze this variability are also reviewed, as well as the various suggested ways of classifying the different types. The geographical distribution and both clinical and biological consequences of this variability are also discussed.

Dogs latently infected with Babesia canis were systematically detected amongst a population kept in an enzootic area over a year. Detection of parasite was carried out on 43 healthy dogs and identified by two blood cultures in an interval of a few months. A serological study was performed using indirect immunofluorescence and Western blot. This study distinguished two distinct groups: asymptomatic carrier dogs (latently infected or premunised-33%) and non-carrier dogs with sterilising immunity. There is no difference between carrier and non-carrier dogs concerning age, breed or history of babesial infection and 36 out of the 43 dogs studied are seropositive. The antibody titer did not completely correlate with the detection of parasitaemia. All carrier dogs are seropositive to Babesia canis, but half of the seropositive dogs are not carriers. This study confirms that serological detection is not a good indicator of latent babesial infection. This study did not detect any difference between antibody responses (quantitative response (IIF) or qualitative response (WB)), related to latent parasitaemia.

Creole goats and cattle in Guadeloupe can be carriers of cowdriosis (heartwater: Cowdria ruminantium) after recovery for a period as long as 11 months in goats and 2 months in cattle. The carrier status was demonstrated by feeding Amblyomma variegatum nymphs on recovered animals and the resulting adult ticks on susceptible goats. Cowdria ruminantium was not detected permanently during the carrier status.

HBsAg was detected in 152 pregnant women among 6,605 (2.3%) screened in the prenatal clinics of four hospitals representative of the Paris metropolitan area. In 98% of cases, HBsAg positivity indicated chronic HBV carrier status. Among patients born out of continental France (47% of screened women, 79% of positive women) relative risk of chronic infection was 6 in Asians, 5.5 in Africans, and 4 in French women born in non-continental France. No significant difference in medical history was seen between HBsAg-positive and HBsAg-negative patients, in any of the birthplace groups. In women born out of continental France, number of children and crowding in the home were correlated with HBsAg-positivity; these correlations were not found in French women born in continental France. In non-African, non-Asian women, screening on the basis of medical, social and familial criteria (simulated in this study) would not be effective. Routine screening for HBsAg in pregnancy is advocated. The cost of the prevention of each case of perinatally acquired chronic HBV infection by routine screening followed by prophylactic treatment of a risk neonates was estimated at 180,000 French Francs (35,000 dollars). This approach is the only means of preventing the long-term life-threatening complications of chronic HBV infection in the 600 neonates born each year in France to HBsAg-positive mothers.

There are more than 280 carriers of the hepatitis B virus worldwide. The risk of chronic carriers, and a fatal outcome due to hepatocarcinoma, is estimated to be about 50% in Asian children contaminated by materno-fetal transmission. Serovaccination of the neonatal infant born to a HBV carrying mother provides protection in nearly 100% of cases. Routine screening for HBV carriers at the Besançon teaching hospital maternity unit led to the vaccination of 1.12% of the babies born in 1990, which corresponds to the current national average.

This study was conducted to assess the usefulness of IgM anti-PGLI antibody test, for the diagnosis of leprosy and of the subclinical infection among contact population. Even if the specificity (97.7%), sensitivity (98% for the multibacillary, but 36% for the paucibacillary) and efficiency (97.7%) of the test for the diagnosis of patients are good, its positive predictive value which is the proportion of true patients among the seropositive subjects detected in the population was very low (1.17% in Polynesia), because of the very low prevalence of leprosy. For the diagnosis of the subclinical infection, our experience based on the follow up of a population of 1,123 contacts, showed that such a control program would have low feasibility and low cost-effectiveness. After 5 years, the proportion of individuals developing the disease was not different among the seropositive than among the seronegative subjects. Finally, only 17.5% of the new cases of leprosy detected, were issued from the contact population followed. In conclusion and in a practical point of view, although this test may contribute to the diagnosis of patients, it is not likely useful neither for the diagnosis nor for the prognosis of leprosy in a population.

CMV can be detected in blood with two techniques: isolation of CMV from the buffy-coat on human embryonic fibroblasts; CMV genome detection by DNA hybridization technique. Isolation of CMV from blood plated on embryonic fibroblasts necessitates a delay of 10-30 days. Using monoclonal antibodies we have developed a 96 hours test to diagnose viremia. Fibroblasts grown on coverslip in tubes are inoculated with buffy-coat. Indirect immunofluorescence test is performed using the monoclonal antibodies E 13, 48 and 96 hours post-infection. DNA-DNA hybridization technique necessitates purification of CMV DNA. CMV DNA is then labelled with 32 P by nick-translation. This labelled DNA is used as probe for detection of CMV genome in DNA extracted from leukocytes. The hybridization is virus-specific. Cytomegaloviremia correlates with active infection and is not indicate of the carrier state of blood donors. CMV genome research in blood can potentially identify infective donors. Further studies are needed to correlate CMV genome detection in blood with presence of CMV antibodies.

The authors relate their experience of integrating screening for African human trypanosomiasis (AHT) caused by T.b. gambiense in a network of multi-purpose health centres at Nioki, Zaire. Since 1983 the health centre nurses have been trained in the laboratory techniques for AHT screening and have been given the essential equipment (microscope, slides, coverslips). The strategy used was that of passive screening of patients who came of their own accord to the health centre: systematic palpation and aspiration of lymph nodes, and examination of wet and/or thick blood films from patients with AHT-like symptoms (fever not responding to antimalarials, headache for over a week, somnolence, arthralgias, pruritus, weight loss). When a trypanosome was detected, the patient was referred to the hospital for confirmation and lumbar puncture. From 1983 to 1987 the proportion of new cases detected by the health centres rose from 0% to 31.1%, while the returns of the mobile teams diminished as the disease regressed. Nevertheless, only 22.1% of the new cases detected by the health centres had normal CSF, as opposed to 64.8% of the new cases detected actively by the mobile teams. These two approaches therefore seem to be complementary: 83% of the new cases detected by the health centres were diagnosed on lymph node aspirates and/or wet films, and it is likely that better use of thick blood films could improve the performance of the health centres.(ABSTRACT TRUNCATED AT 250 WORDS)

One hundred and forty eight faecal specimens were collected from 40 newborn infants during an outbreak of rotavirus infections in a neonatal unit. Rotavirus was sought every 3 days by immunoelectron microscopy (IEM) and was found in 12 newborn babies. Rotavirus excretion persisted for up to 6 days after healing of the diarrhoea. No significant difference was found between infected (n = 12) and uninfected (n = 28) infants with regard to gestational age (35.2 +/- 3.7 vs 36.9 +/- 2.6 weeks), birth weight (2,064 +/- 693 vs 2,197 +/- 529 g), and postnatal ages at the time of the outbreak. The 148 stool specimens were analysed by IEM considered the reference technique and compared with two ELISA methods, and three Latex methods. Rotavirus was identified by IEM in 20 stools. Equivocal results were observed with Slidex Rotakit Polyclonal (16.9%), Slidex Rotakit Monoclonal (2.7%) and Rotalex (13.8%). The positive and negative predictive values were respectively 87.5% and 96.9% for the Slidex Rotakit Monoclonal test, 86.7% and 94.7% for the Rotazyme II test, 100% and 95.5% for the ELISA monoclonal test.

A global review of the problem of malaria accidentally transmitted by blood transfusion is reported in France during these last twenty years. A survey by IFA test of possible reservoir hosts of Plasmodium among 2571 donors from the blood transfusion Centers of Marseille and Nice is reported. The incidence of the stay (frequency and longtime) in infested countries and the interval from the last infestation possible to the IFA test are very important factors. Several preventive methods are discussed. The author proposes this scheme: the donors frequently going to infested countries will be used only for preparing chemical plasma fractions. For the other donors the blood will be used for preparing whole blood, red cells, fresh or frozen plasma, platelet and leucocyte preparations in which a few parasites can be present, only if IFA test is negative 4 months after their coming back in our country. Nevertheless this screening beginning by an interrogation can be fallible. Therefore, there is no absolute preventive method. Physicians, Surgeons and Anesthetists must be forewarned.

HBs Ag subtypes ad and ay were determined by counter-electrophoresis (CEP) among 301 persons from Casablanca found HBs Ag positive by CEP: 147 were asymptomatic HBs Ag carriers and 154 were patients with acute or chronic hepatitis. w and r determinants were investigated among 82 from them only. HBe antigen and antibody (AB) were investigated by gel double immunodiffusion among 294 persons. Into the whole population, the prevalence of ad and ay subtypes was respectively 20 and 80%. This distribution, intermediate between those reported in West Europe and West Africa, was in agreement with data previously reported by others in the Maghreb, but differing from these ones in the distribution of w and r determinants. ayr subtype was found dominant (39%) and adw rare (2.4%), the prevalences of adr and ayw being intermediate (25-30%). Among asymptomatic HBs carriers and patients only adr and ayr distribution differed: in the formers, adr was dominant and ayr rare and, in contrast, ayr was frequent and adr rare among patients. Elsewhere, some findings were in agreement with previously reported data by others, such as the frequent association of ad to chronic liver disease or long-term HBs Ag carriage, ay being rather associated to short-term carriage, the frequency of HBe Ab in ad subtype and the presence of ay among almost all HBs positive haemodialysed patients.

The purpose of this study was to compare the results of 3 reverse passive haemagglutination techniques currently used by blood centers for the HBS antigen screening in donors' blood. A comparison was also made with 3 other techniques: Radio-immuno-assay (RIA), Counter-electrophoresis (CEP), Complement fixation (CF). The sera from 2.028 blood donors were screened by all those techniques, as well as 105 known sera, used as references (87 HBS antigen positive sera with different titers, 18 HBS antigen negative sera) and coming from 4 origins: NIH-Bethesda, Centre National de Transfusion Sanguine, Paris; Hôpital de la Pitié-Salpêtrière, Paris; Hôpital Broussais, Paris. The reverse passive haemagglutination techniques were shown to be slightly less sensitive than RIA and definitely more sensitive than CEP and CF, since 18 sera were HBS antigen positive with RIA (0.88%), 10 or 12 with haemagglutination (0.40-0.59%), 8 with CF (0.39%) and 7 with CEP (0.34%). The frequency of false positive results changed with the haemagglutination technique used (0.84% for WH.HBS, to 2.3% for Hepanosticon) and involved confirmatory tests (absorption and/or neutralisation). In sum, the sensitivity, specificity and practicability of the 3 haemagglutination techniques were shown to be nearly identical, with a slight but sure advantage for the WH.HBS in our experiment. Thus reverse passive haemagglutination techniques seem, at the present time, to be the best ones for HBS antigen screening when RIA cannot be applied.