[The last offensive of leprosy in the South Pacific Ocean: the epidemic on Rapa (1922-1950)]. / Ultime offensive de la lèpre dans le Pacifique sud: l'épidémie de Rapa (1922-1950).

The observations of leprosy outbreaks are exceptional and always situated in isolated countries. The authors give the example of Rapa, small island in French Polynesia, where an epidemic has occurred from 1922 to 1950. They made the study of the different parameters by retrospective methods and fieldwork. After an 11% incidence rate and an 68% prevalence rate, the outbreak seems today off. Now leprosy is endemosporadic.

HLA in two islands of French Polynesia.

The HLA-A, B, and C antigens of 243 individuals from two Polynesian islands, Maiao and Hiva Oa, have been characterized. 328 haplotypes were defined by family analysis. Most frequent antigens were A2, A11, Aw24, A26 , Aw34 ; Bw38, Bw39 , Bw48 , Bw55 , Bw56 , Bw60 ; Cwl, Cw3, and Cw4. Several other antigens were present at low frequency or were present on only one island. New variants of Bw22 and B40 were found. Despite an overall similarity in antigens of the two islands, the combination of HLA-A, B and C antigens on the haplotype were distinctive. Of 328 total haplotypes identified, 65 were unique. Thirteen of these (20%) were present on both islands. Twenty-eight (43%) were unique to Hiva Oa and 24 (37%) were unique to Maiao . Significant, positive linkage disequilibrium values (delta) for HLA-A, B and HLA-B, C antigens were also different for the two populations.

The use of mosquitoes (Aedes aegypti) to detect ciguatoxin in surgeon fishes (Ctenochaetus striatus).

A new animal assay to detect ciguatoxin in fishes was developed. Mosquitoes were subjected to intrathoracic injection of serial dilutions of ciguatoxin crude extracts. Toxicity of the fishes was expressed as the mosquito LD50 (g of flesh per mosquito). A significant correlation between the mosquito bioassay and the mouse bioassay performed on the same extracts was shown (r = 0.72, n = 80). We were able to detect 96% of the toxic fishes, while 91% of the fishes non-toxic in mice were also non-toxic in mosquitoes.

[Assay for detection of ciguatoxin using an immunoenzyme technic]. / Essai de détection de la ciguatoxine par une méthode immunoenzymatique.

The ELISA method has been used to detect possible anticiguatoxin antibodies in the tissues of toxic fishes. Thin lamellae of toxic fish muscles have been brought into contact on the one hand with antibodies obtained after immunization of the rabbit and the mouse by a human serumalbumine ciguatoxin conjugate and on the other hand with human sera of ciguatera convalescent. These various antibodies have been recognized by peroxydase labelled anti-rabbit, -mouse and -human antibodies. It has been not possible to show off specific antibodies of the ciguatoxin in the various immune sera tested by this immuno-enzymatic method.

[Dengue outbreak by virus type 4 in French Polynesia. I. General epidemiology - clinical specific aspects (author's transl)]. / La dengue due au virus de type 4 en Polynésie Francaise. I.--Epidémiologie générale aspects cliniques particuliers.

Authors describe an extensive outbreak of dengue 4 virus which is observed for the first time out of its Asian original focus. The whole archipelagos of French Polynesia have been contaminated in a space of four months. Usual form of the disease is typical with lightness of the symptoms. This outbreak has been implicated in the death of a child by shock; and two cases of reversible encephalitis have been certainly caused by this virus. The neurotropism is the main characteristic of dengue virus type 4.

[Dengue outbreak by virus type 4 in French Polynesia. II. Preliminary biological observations on epidemiology and physiopathology of the disease (author's transl)]. / La dengue due au virus de type 4 en Polynèsie Francaise. II.--Observations biologiques liminaires sur quelques points prècis d'èpidèmiologie et de physiopathologie.

Authors report some accurate epidemiologic and physiopathologic data about dengue 4. Thanks to virus intrathoracic inoculation in Toxorhynchites amboinensis (Doleshall, 1857), 202 viral strains have been isolated from 633 sera samples. The incidence of the disease has decreased very early after immunization of the whole population and resulted in an eradication of dengue type 1 virus which was endemic in French Polynesia since 1976. Only one type of dengue virus seems to be tolerated in French Polynesian ecosystem in the same time. There is no crossing protection with dengue 1. Clinically, the picture has been the same in both new and previously infected by dengue 1 patients. Duration of viremia during the secondary dengue fever is not shorter than in the primary one. The hemagglutination inhibiting antibodies do not protect patients, but do not result in immune-complexes pathology.

[The HBs antigen carriage in blood donors of French Polynesia A new antigenic sub-type (author's transl)]. / Le portage de l'antigène HBs chez les donneurs de sang de Polynesie françaisse. Un nouveau sous-type antigenique.

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.

[Enzyme immunoassay for the detection and identification of dengue viruses from infected mosquitoes (author's transl)]. / Méthode immunoenzymatique de détection et typage des virus de la dengue à partir de moustiques infectés.

The authors deal with a "double sandwich" enzyme immunoassay for the detection and identification of dengue viruses 1, 2 and 4. They use ground glass-beads (7 mm diameter) coated with human heterospecific anti-dengue antibodies, to bind viruses obtained from infected mosquitoes (Toxorhynchites amboinensis). The mouse antibodies bound to the viruses coated on the beads are revealed by anti-mouse 7S immunoglobulins labelled with peroxydase. The method is practical, sensitive and confident. The standard curves obtained with each type show significant differences from one another until very high dilutions of the viral suspension. Inhibition tests by human immune antibodies and dengue antigens demonstrate the specificity of the reaction. This method is certainly applicable to others arboviruses and allows a large scale epidemiological survey.

[Neurologic complications of ciguatera]. / Complication neurologique de la ciguatera.

The authors report a case of severe two phases fish poisoning, treated at hospital and ruled by a complex neurological picture with both central and peripheric manifestations. The detailed data, they have got about the disease, are an opportunity to discuss the various pathogenic procedures of human ciguatera.