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J F Roux

Publications and source records attributed to J F Roux.

104 records · Page 6Linked to original sources
PubMedDate not supplied

Effect of two successive annual treatments with single doses of ivermectin on microfilaraemia due to Wuchereria bancrofti var. pacifica.

Between 1986 and 1988 a single-blind, dose-ranging study was carried out in French Polynesia to determine the efficacy and tolerability of single 50, 100, 150 and 200 micrograms/kg doses of ivermectin in Wuchereria bancrofti carriers. Forty male microfilariae (mf) carriers between 18 and 50 years of age, in whom mf density was greater than or equal to 20 mf/ml, were treated twice at a one-year interval. Twelve months after the second treatment, in carriers who were given a dose greater than or equal to 100 micrograms/kg, mean mf density was 4-7% of the initial pretreatment mf density. Therefore, several successive annual treatments with single doses greater than or equal to 100 micrograms/kg of ivermectin should result in reducing mf densities to a very low level. Nevertheless, at 9 months after the second treatment, residual parasitaemia ranged from 1 to 2182 mf/ml (median 85) in 30 patients. Finally, in patients with pretreatment mf counts less than or equal to 150 mf/ml, mean mf density was 2.8 and 8.9 mf/ml, respectively, during the 2 six-month periods following treatment, while in patients with pretreatment mf densities greater than 150 mf/ml (median 1500) it was 92.3 and 334.1 mf/ml during the same periods. These results suggest that, when implementing filariasis control programmes, the best strategy might be administration of several treatments with a single dose of ivermectin every 6 months to the entire population, at least in French Polynesia. Afterwards, when mf densities had been reduced to a relatively low level (100-150 mf/ml), annual treatments could be considered.

Adolescent↗
PubMedDate not supplied

One year evaluation of immunogenicity conferred by a Chinese hamster ovary cell recombinant hepatitis B vaccine in a French Polynesian newborn immunization programme.

In 1988, a hepatitis immunization programme, using a Chinese hamster ovary (CHO) cell recombinant vaccine, was implemented for newborn children in the Austral archipelago (French Polynesia). Three different schedules were used: (i) 4 vaccine doses at months (M) 0, M1, M2 and M12; (ii) 3 vaccine doses at M0, M1, M6; and (iii) 3 vaccine doses at M0, M1, M2. Results at the one year follow-up may be summarized as follows. Of 197 infants who received one or more doses of CHO-recombinant vaccine, (i) none was an HBsAg carrier; (ii) 89.5% had anti-HBs-antibody titres greater than 10 miu/ml; and (iii) 95.9% had seroconverted for at least one of the 2 antibodies studied (anti-HBs or anti-pre-S2). After 2 doses (M0, M1), anti-HBs seroconversion rate and geometric mean titre were, respectively, 82.6% and 98.47 miu/ml. After 3 doses, seroconversion rates and geometric mean titres were, respectively, 91.1% and 200.59 miu/ml using schedule M0, M1, M2, and 100% and 1253.4 miu/ml using the M0, M1, M6 schedule. None of the 7 vaccinated neonates born to HBsAg/HBeAg positive mothers was found to be an HBsAg carrier. These preliminary results indicate that, in field conditions, vaccination with a CHO-recombinant vaccine resulted in high immunogenicity.

Female↗
PubMedDate not supplied

Microfilariae recurrence in Polynesian Wuchereria bancrofti carriers treated with repeated single doses of 100 micrograms/kg of ivermectin.

Forty-six Polynesian carriers of Wuchereria bancrofti were treated with 3 successive single doses of ivermectin, 100 micrograms/kg, given every 6 months. Immediate microfilaricidal activity of ivermectin was excellent in all carriers, since residual mean microfilaraemia levels, 2 d after each of the 3 treatments, were less than 1% of pretreatment levels. Before initial treatment, geometric mean microfilaraemia was 500 microfilaria (mf)/ml for the whole group (range 21-6398 mf/ml); 6 months after each successive treatment it was 197, 108 and 87 mg/ml, respectively, 39.4, 21.6 and 17.4% of the pre-initial treatment level. By considering the mean percentage recurrent level at 6 months after the 3rd treatment (36.8%) as a threshold, it was possible to classify the carriers into 2 groups: 17 in whom the percentage recurrent level was > 36.8% and who were considered as 'fast repopulating' individuals, and the remaining 29 who were considered as 'slow repopulating' individuals. In the latter group, 6 months after each of the 3 treatments, the recurrent microfilaremia levels were 22.7%, 8.0% and 4.9% of the pre-initial treatment level, respectively, while they were 95.1%, > 100% and > 100% in the former. The constant recurrence of mf suggests that ivermectin, at a dosage of 100 micrograms/kg, had no effect on adult worms in 'fast repopulating' individuals, whereas the progressive lessening in recurrence of mf suggests some activity (sterilizing or killing) of ivermectin on W. bancrofti macrofilariae in 'slow repopulating' individuals.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMedDate not supplied

Population genetics of abnormal haemoglobins in Burkina Faso, west Africa.

The gene frequencies of haemoglobin A (HbA), HbS and HbC were studied in Burkina-Faso (BF) and in a neighbouring region of Niger, Ayorou. The frequency of HbS was higher in the Sahel region, (northern part of BF and Ayorou) than in the Savanna region. The reverse was true for the HbC gene. The major findings of this study are: (a) confirmation of a peak of HbC gene frequency in the central region of BF (Mossi plateau); (b) a possible negative correlation between the frequencies of HbS and HbC-Cavalli-Sforza and Bodmer have observed that this correlation is at a significantly different level from that expected because of the allelic relationship between HbS and HbC; (c) comparison with the data collected by Livingstone shows a modification in the fitness of the different genotypes in the last thirty years: AS individuals have a lower and AA and SS a higher fitness. Our data favour a partial selection relaxation in this region.

Burkina Faso↗
PubMedDate not supplied

[Technics of detection and diagnosis of African trypanosomiasis in humans].

The authors review the most recent and sophisticated laboratory techniques for screening and diagnosis of human african trypanosomiasis. Immunological screening: indirect immunofluorescence, card agglutination test. Parasitological diagnosis: hematocrit centrifuge technique, miniature anion exchange/centrifugation, cerebrospinal fluid centrifugation. For each of these techniques, the authors deal successively with principle and method, interest, possible applications.

Agglutination Tests↗
PubMedDate not supplied

[The HBs antigen carriage in blood donors of French Polynesia A new antigenic sub-type (author's transl)].

In the blood transfusion center of Papeete )Tahiti Island), a survey on HBs antigen has been made in 5 406 blood donors by reverse hemagglutination method. Its shown 2,53 p. 100 of carriers. In european donors recently arrived in the territory, the rate of carrier state is 0,27 p. 100 versus 3,01 in the autochtonous donors. From this point of view, the situation of Polynesia is better than that prevailing in some of the suroundings territories but worse than in developped countries. French Polynesia is too extended and too heterogenous to permit an extrapolation of our data to the whole territory. Anyway, the study of the geographical origin of the carriers, if compared to that of the donors, gives evidence that the prevalence of HBs antigen carriage is higher in remote archipelagos than in Tahiti. The research of subtypes of HBs antigen shown the presence of a new subtype adr q negative which seems very particular to South Pacific.. In french Polynesia it seems localized to some archipelagos. In addition, the frequence and preponderance of adw4 subtype in other archipelagos have been compiled. The data collected lead to ethnological hypothesis. More extensive epidemiological studies appear necessary to precise the frequency of HBs antigen carriage-state and the subtypes distribution in the various archipelagos of the territory.

Blood Donors↗
PubMedDate not supplied

[Control of hepatitis B in French Polynesia with a program of systematic vaccination of newborns with the Genhevac B vaccine].

In 1988, a 5-year vaccination program against hepatitis B was launched for all newborns in a pilot area, the Austral archipelago in French Polynesia. Genhevac B, a recombinant vaccine produced from mammalian cells was administered. Three different immunization schedules were used, none of them including additional specific immunoglobulin: i) four doses, one at each months (M) 0, 1, 2, and 12; ii) three doses one at each MO, M1 and M6; and iii) three doses one at each MO, M1 and M12. Each year during the 5 year period a serological survey was conducted. Of the 837 children who received at least one vaccine dose, 5 were HBsAg carriers. Seroprotection rates for anti-HBs and anti-PreS2 antibodies were 88% after one dose and 97% after two doses. After the third dose, seroprotection rates and geometric mean titers of anti-HBs antibodies were 95% and 217 mIU/ml for schedule (i) (three dose only); 92% and 389 mIU/ml for schedule (ii) and 93% and 344 mIU/ml for schedule (iii) respectively. After four doses (schedule i) the values were 100% and 1228 mIU/ml. Of the 18 newborns whose mothers were positive for both HBsAg and HBeAg, one was a HBsAg carrier. The estimated protective rate for prevention of perinatal transmission was 94%. This study suggests that in field conditions, systematic vaccination of newborns without using specific immunoglobulins can confer early protection. The schedule recommended for use in French Polynesia was three doses, at MO, M1 and M6-12 (between 6 and 12 months) with an additional booster dose at age 6 years, the last year of nursery school. Since April 1992, all children born in French Polynesia have been vaccinated according to this schedule. A catch-up program has been implemented for children aged 4 to 10 years old using a similar immunization schedule.

Child↗