Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Seychelles”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources

Leptospirosis in the Seychelles.

OBJECTIVE: To ascertain the incidence of leptospirosis in the Seychelles, identify its sources, review diagnostic features and assess complications. DESIGN: A prospective survey over a two-year period 1988-1990 of all cases diagnosed as having leptospirosis at Victoria Hospital, the main referral hospital for the Islands. RESULTS: Eighty cases were diagnosed on clinical grounds with serological confirmation in 58 (73%). Leptospira interrogans serovar icterohaemorrhagiae was identified in 27 (33%) and serovar autumnalis in 2 (3%), there was broad cross-reactivity in the other specimens. In a further 7 (9%), the diagnosis was confirmed at autopsy. Useful diagnostic aids were the finding of myalgia in 68 (85%) and a raised creatine phosphokinase (CPK) level in 61 (76%). CPK elevation was found to be a more reliable indicator of disease the earlier in the illness it was measured. Other important clinical signs are reviewed. Sixty (76%) were regular drinkers suggesting a relationship with home-brewed alcohol, 48 (60%) were in at-risk occupations; 13 (16%) deaths resulted. CONCLUSIONS: Leptospirosis in the Seychelles is likely to be rat borne. An annual incidence of 60 per 100,000 was found with significant mortality. Muscle tenderness and raised CPK levels were the most reliable early diagnostic aids.

Adult↗

[Survey of application of acupuncture and moxibustion in Seychelles].

Survey of application of acupuncture and moxibustion in Seychelles are introduced from acupuncture and moxibustion methods, accepting degree of patients and therapeutic effects, etc.. The authors hold that acupuncture and moxibustion have superiority in treatment of pain diseases, especially bony arthritis of loin and knee in Seychelles, and indicate that application of acupuncture and moxibustion are influenced by recognition for acupuncture and moxibustion, medical system, problem in acupuncture and moxibustion, quality of acupuncturist, and other factors.

Acupuncture Therapy↗

Seroepidemiology of bancroftian filariasis in the Seychelles Islands.

Wuchereria bancrofti is the only human filarioid present in the Seychelles archipelago. The last parasitological survey carried out in Mahé revealed a microfilaraemia rate of 3.6%. Serum samples from 417 native individuals living in Mahé were tested for the presence of filarial antibodies by ELISA method, using crude soluble extract of Brugia pahangi adult worm as antigen. The results seem to show a proportion of the population (17%) has been exposed to W. bancrofti (with OD values greater than 0.5) and 7% (with OD greater than 0.7) have specific filarial antibodies. The pattern of distribution of antibody levels in the sample population studied strongly suggest that filariasis is still endemic in Seychelles (Mahé).

Adolescent↗

Field evaluation of a one-step dipstick assay for the diagnosis of human leptospirosis in the Seychelles.

OBJECTIVE AND METHOD: To compare the response of a dipstick assay (DSA) detecting Leptospira-specific immunoglobulin M (IgM) antibodies with that of an enzyme-linked immunosorbent assay (ELISA), an indirect haemagglutination assay (IHA), the microagglutination test (MAT) and a polymerase chain reaction assay (PCR) in patients with leptospirosis confirmed by MAT alone or by MAT and/or PCR (MAT/PCR). RESULT: In 75 patients with acute leptospirosis diagnosed by MAT (respectively, 90 patients diagnosed by MAT/PCR), the response in paired early and convalescent sera was positive in 78.9% (67.9%) by DSA, 76.0% (67.8%) by ELISA, 58.7% (55.6%) by IHA, 44.0% (53.3%) by PCR, and 100% (90.0%) by MAT. In early serum only, the response in patients diagnosed by MAT (respectively by MAT/PCR) was positive in 36.0% (38.9%) by DSA, 36.0% (37.8%) by ELISA, 14.7% (18.9%) by IHA, 39.2% (48.3%) by PCR, and 53.3% (58.9%) by MAT titre > or =1:100. DSA detected the main serogroups implicated in human leptospirosis in Seychelles and demonstrated sensitivity comparable to ELISA. In 124 single sera from control subjects without overt disease, the response was positive in 4.8% by DSA, 3.2% by ELISA, 3.2% by IHA, 13.8% by PCR, 37.9% by MAT titre > or =1:100, and 2.4% by MAT titre > or =1:800, giving evidence of the frequency of both past and current subclinical infection in Seychelles and that DSA was less sensitive than MAT to detect moderate levels of leptospiral antibodies. CONCLUSION: DSA is a simple and reproducible assay well adapted to field conditions and could usefully contribute to the evaluation of leptospirosis in areas devoid of serological laboratory facilities.

Acute Disease↗

Variability within the Seychelles cytoplasmic incompatibility system in Drosophila simulans.

In Drosophila simulans, we described a cytoplasmic incompatibility (CI) system (Seychelles) restricted to insular populations that harbor the mitochondrial type SiI. Since then, these populations have been shown to be heterogeneous, some being infected by one Wolbachia genetic variant only (wHa), while others are infected simultaneously by wHa and by another variant (wNo) always found in association with wHa. We have experimentally obtained two D. simulans strains only infected by the wNo variant. This variant determines its own cytoplasmic incompatibility type. In particular, the cross between wNo-bearing flies and wHa-bearing ones is bidirectionally incompatible. The Seychelles CI type, stricto sensu, is distinguished by being determined by the simultaneous presence of two Wolbachia variants that we found to be mutually incompatible. In addition, we observed incomplete maternal transmission of the Wolbachia.

Animals↗

Mate guarding in the Seychelles warbler is energetically costly and adjusted to paternity risk.

Males may increase their fitness through extra-pair copulations (copulations outside the pair bond) that result in extra-pair fertilizations, but also risk lost paternity when they leave their own mate unguarded. The fitness costs of cuckoldry for Seychelles warblers (Acrocephalus sechellensis) are considerable because warblers have a single-egg clutch and, given the short breeding season, no time for a successful replacement clutch. Neighbouring males are the primary threat to a male's genetic paternity. Males minimize their loss of paternity by guarding their mates to prevent them from having extra-pair copulations during their fertile period. Here, I provide experimental evidence that mate-guarding behaviour is energetically costly and that the expression of this trade-off is adjusted to paternity risk (local male density). Free-living males that were induced to reduce mate guarding spent significantly more time foraging and gained significantly better body condition than control males. The larger the reduction in mate guarding, the more pronounced was the increase in foraging and body condition (accounting for food availability). An experimental increase in paternity risk resulted in an increase in mate-guarding intensity and a decrease in foraging and body condition, and vice versa. This is examined using both cross-sectional and longitudinal data. This study on the Seychelles warbler offers experimental evidence that mate guarding is energetically costly and adjusted to paternity risk.

Animals↗

Pre-ovulation control of hatchling sex ratio in the Seychelles warbler.

Females of some bird species have a high degree of control over the sex ratio of their offspring at laying. Although several mechanisms have been put forward to explain how females might control the sex of their eggs, virtually nothing is known. As females are the heterogametic sex in birds, adjustment of the clutch sex ratio could arise either by pre- or post-ovulation control mechanisms. The Seychelles warbler (Acrocephalus sechellensis) exhibits extreme adaptive egg sex ratio bias. Typically, warblers produce only single-egg clutches, but by translocating pairs to vacant habitat of very high quality, most females were induced to produce two-egg clutches. Overall, females skewed clutch sex ratios strongly towards daughters (86.6%). This bias was evident in the first egg, but critically, also in the second eggs laid a day apart, even when all absent, unhatched, or unsexed second eggs were assumed to be male. Although a bias in the first egg may arise through either pre- or post-ovulation mechanisms, the skew observed in second eggs could only arise through pre-ovulation control. Post-ovulation adjustment may also contribute to skewed hatchling sex ratios, but as sex-biased release of gametes is likely to be a more efficient process of control, pre-ovulation mechanisms may be the sole means of adjustment in this species. High fitness differentials between sons and daughters, as apparent in the Seychelles warblers, may be necessary for primary sex ratio adjustment to evolve.

Animals↗

Human T-lymphotropic virus type I antibodies in the serum of patients with tropical spastic paraparesis in the Seychelles.

Tropical spastic paraparesis (TSP), a chronic myelopathy of unknown etiology, was studied in the Seychelles. Human T-lymphotropic virus type I (HTLV-I) and human immunodeficiency virus antibodies were determined using an enzyme-linked immunosorbent assay and confirmed with an indirect fluorescent antibody test in serum samples of 20 patients with TSP and 16 controls. Test results indicated that 17 patients (85%) and two controls (transverse myelopathy and clinically probable multiple sclerosis) were positive for HTLV-I. Serum samples of nine healthy controls and five with other neurologic diseases were negative for HTLV-I. No serum samples were positive for human immunodeficiency virus. Estimated relative risk for TSP in those subjects whose serum is positive for HTLV-I antibodies is 40. This result is highly statistically significant. Although primarily associated with adult T-cell leukemia and non-Hodgkin's lymphoma, HTLV-I could also be an etiologic agent of TSP.

Adult↗

Secondary analysis from the Seychelles Child Development Study: the child behavior checklist.

Human exposure to methylmercury (MeHg), a known neurotoxin, is primarily from fish consumption. As part of a large study examining the association between MeHg exposure and child development in a population with high fish consumption we examined school-age behavior using the Achenbach Child Behavior Checklist (CBCL). The CBCL Total T score was a primary endpoint and was reported earlier to show no adverse association with prenatal or postnatal MeHg exposure. In this study we analyzed the T scores of the CBCL subscales to determine if more discrete aspects of measured behavior were associated with exposure. The Seychelles Child Development Study (SCDS) is a prospective, double blind, longitudinal evaluation of over 700 children. The index of prenatal exposure was maternal hair total mercury (T-Hg) in a segment growing during gestation. Postnatal exposure was T-Hg in the child's hair taken at 66 months of age. The child's primary caregiver completed the CBCL during the 66-month evaluation. No association between prenatal or postnatal MeHg exposure and the CBCL subscales was found. In Seychellois children exposed to MeHg from consumption of ocean fish we found no association between either prenatal or postnatal MeHg exposure and behavior as measured by the CBCL subscales.

Adult↗

Pediculus humanus capitis on children in Mahé, Seychelles.

The incidence of Pediculus humanus capitis infestation in pre-school and schoolchildren in Mahé, Seychelles, was investigated. High infestation rates were discovered, particularly in urban schoolchildren at district schools. Infestation in pre-schoolchildren increased with age. Girls were more infested than boys. Control of infestation will not be possible using only the child health service and the school health service. A combined approach is necessary based on the family unit.

Age Factors↗

Birth weight of infants in The Seychelles.

In 1977, a retrospective survey was made of all singleton live births in one year at Victoria Hospital, Seychelles. The mean weight of male infants was 3105 (S.D. 526 g) and of female infants was 3019 (S.D. 498 g). Birth weight of females increased with maternal age and parity whilst males showed a peak birth weight at maternal age 21 to 30 years and at parity one to two.

Adult↗

Prenatal methyl mercury exposure from fish consumption and child development: a review of evidence and perspectives from the Seychelles Child Development Study.

Evidence from an outbreak of methyl mercury (MeHg) poisoning in Iraq suggested that adverse effects of prenatal exposure on child development begin to appear at or above 10ppm measured in maternal hair. To test this hypothesis in a fish-eating population, we enrolled a cohort of 779 children (the main cohort) in the Seychelles Child Development Study (SCDS). The cohort was prenatally exposed to MeHg from maternal fish consumption, and the children started consuming fish products at about 1 year of age. Prenatal exposure was measured in maternal hair and recent postnatal exposure in the child's hair. The cohort has been examined six times over 11 years using extensive batteries of age-appropriate developmental tests. Analyses of a large number of developmental outcomes have identified frequent significant associations in the appropriate direction with numerous covariates known to affect child development, but only one adverse association between prenatal MeHg exposure and a developmental endpoint. Because such results could be ascribed to chance, there is no convincing evidence for an association between prenatal exposure and child development in this fish-eating population. Secondary analyses have generally supported the primary analyses, but more recently have suggested that latent or delayed adverse effects might be emerging at exposure above 10-12ppm as the children mature. This suggests that the association between prenatal exposure and child development may be more complex than originally believed. This paper reviews the SCDS main cohort study results and presents our current interpretations.

Animals↗

Methylmercury and neurodevelopment: longitudinal analysis of the Seychelles child development cohort.

BACKGROUND: The Seychelles Child Development Study (SCDS) has been longitudinally following a cohort of over 700 children enrolled in 1989. Their mothers consumed a diet high in fish during pregnancy. Repeated examination of the SCDS cohort at six different ages through age 11 years has shown no pattern of adverse effects. Some early appearing beneficial associations between both prenatal and postnatal hair MeHg and several child development endpoints were noted. We hypothesized these might be related to micronutrients in the fish, but they were not found when the children reached middle school age. These findings suggest that the associations observed between MeHg and developmental outcomes may vary with developmental stage. METHOD: We examined the main cohort of the SCDS to determine if this might be true using a longitudinal multiple regression analysis design that focused on those endpoints that were repeatedly measured at different ages. The primary endpoint analyzed was global cognition, involving a measure of developmental quotient or IQ. Secondary analyses included other domains such as Reading and Mathematics scholastic achievement, social behavior, and memory. Analyses involved two different approaches, one including incorporation of a passage of time variable, the other including a difference of scores across time points. RESULTS: No significant associations were found between prenatal MeHg exposure and any of the repeatedly measured endpoints. CONCLUSIONS: These results suggest that even when individual subject variance is controlled there was no consistent pattern of associations between child development outcomes and prenatal exposures to MeHg from maternal consumption of a diet high in fish. The Seychellois diet contains about 10 times more ocean fish than is typically consumed by US citizens. Our primary focus on IQ should further inform growing scientific interest in the analysis of the risks and benefits of fish consumption on overall cognitive ability.

Child↗

Pulmonary haemorrhage as a predominant cause of death in leptospirosis in Seychelles.

We examined the cause of death during a 12-month period (1995/96) in all consecutive patients admitted to hospital with leptospiral infection in Seychelles (Indian Ocean), where the disease is endemic. Leptospirosis was diagnosed by use of the microscopic agglutination test and a specific polymerase chain reaction assay on serum samples. Seventy-five cases were diagnosed and 6 patients died, a case fatality of 8%. All 6 patients died within 9 days of onset of symptoms and within 2 days of admission for 5 of them (5 days for the 6th). On autopsy, diffuse bilateral pulmonary haemorrhage (PH) was found in all fatalities. Renal, cardiac, digestive and cerebral haemorrhages were also found in 5, 3, 3 and 1 case(s), respectively. Incidentally, haemoptysis and lung infiltrate on chest radiographs, which suggest PH, were found in 8 of the 69 non-fatal cases. Dengue and hantavirus infections were ruled out. In conclusion, PH appeared to be a main cause of death in leptospirosis in this population, although haemorrhage in other organs may also have contributed to fatal outcomes. This cause of death contrasts with the findings generally reported in endemic settings.

Adult↗

MHC diversity in two Acrocephalus species: the outbred Great reed warbler and the inbred Seychelles warbler.

The Great reed warbler (GRW) and the Seychelles warbler (SW) are congeners with markedly different demographic histories. The GRW is a normal outbred bird species while the SW population remains isolated and inbred after undergoing a severe population bottleneck. We examined variation at Major Histocompatibility Complex (MHC) class I exon 3 using restriction fragment length polymorphism, denaturing gradient gel electrophoresis and DNA sequencing. Although genetic variation was higher in the GRW, considerable variation has been maintained in the SW. The ten exon 3 sequences found in the SW were as diverged from each other as were a random sub-sample of the 67 sequences from the GRW. There was evidence for balancing selection in both species, and the phylogenetic analysis showing that the exon 3 sequences did not separate according to species, was consistent with transspecies evolution of the MHC.

Animals↗

Seroepidemiology of infection with hepatitis A virus and hepatitis B virus in the Seychelles.

A batch of 417 serum samples obtained from native-born subjects were tested for the presence of hepatitis B surface antigen (HBsAg) and corresponding antibody (anti-HBs), by enzyme-linked immunosorbent assay (ELISA); and antibodies to hepatitis B core antigen (anti-HBc), e-antigen (anti-HBe), and hepatitis A virus (anti-HAV), by radioimmunoassay (RIA). HBsAg was found in only two of the 417 subjects studied. Anti-HBs was detected in 112 samples (26.8%), anti-HBc in 114 (27.3%) and anti-HBe in 31 samples (7.4%). Serologic evidence of a previous or present infection by hepatitis B virus (HBV) was found in 34.5% of the samples studied. Males showed a greater prevalence of anti-HBs and anti-HBc, while anti-HBe was more common in females; however, these differences were not significant. With regard to age, a significantly higher prevalence of anti-HBs (p less than 0.05), anti-HBc (p less than 0.025) and anti-HBe (p less than 0.025) was found in the older age groups. Anti-HAV antibodies were present in 90% of the subjects studied, with no variation between the sexes. The anti-HAV rate in the group under 20 years was similar to that found in the older age groups. The total infection rate of hepatitis B virus in the Seychelles is lower than in other tropical areas, HBs antigen/antibody ratio approaching that in temperate areas. Elucidation of the reasons for the low prevalence of hepatitis B virus carriers among the Sevchelles population requires further investigation.

Adolescent↗

Experimental evidence that kin discrimination in the Seychelles warbler is based on association and not on genetic relatedness.

In cooperative breeding systems driven by kin selection, effective kin-recognition cues are important. Recognition could be achieved by the direct assessment of the genetic relatedness of individuals or by learning through association. In the Seychelles warbler, Acrocephalus sechellensis, female subordinates maximize indirect fitness by preferentially helping genetically related nestlings. Help seems to be based on the continued presence of the primary female who previously fed the subordinate in the nest but it has, so far, been impossible to discount the direct assessment of genetic relatedness. We used a cross-fostering experiment to separate the two possible cues. Adult birds did not discriminate between their own and cross-fostered eggs or nestlings. Cross-fostering resulted in nestlings that were unrelated to the primary female that raised them, but control nestlings were closely related to their primary females. The proportions of cross-fostered and control female offspring that stayed and became helpers on their 'natal' territory were similar. However, for both groups the chance of becoming a subordinate helper was associated with the continued presence of the primary female and not with any other factor tested. Our study provides strong evidence that helping decisions are based on associative-learning cues.

Animals↗

Testosterone, cuckoldry risk and extra-pair opportunities in the Seychelles warbler.

In male birds, testosterone (T) plays an important role in aggressive and mate-attraction behaviour. In the cooperatively breeding Seychelles warbler, Acrocephalus sechellensis, extra-group copulations (EGCs) occur frequently, but are not accompanied by sexual courtship displays as in within-pair copulations. Paternity is nearly always gained by primary males. We investigated whether T levels and sperm storage capability (cloacal protuberance (CP)) in adult primary and subordinate males were related to timing of egg laying, levels of cuckoldry and extra-group paternity (EGP) opportunities. During the sexually active period before egg laying, T levels and CP were only elevated or enlarged (respectively) in primary males, and some suggestion was found that subordinate males do not invest in elevated T levels. The peak in T occurred during the fertile period of the female partner and corresponded to the peak period of male sexual displays and mate guarding, but was independent of cuckoldry risk (density of neighbouring primary males). CP was also enhanced during this period; however, CP but not T remained elevated after egg laying by their mates, and CP but not T was positively related to EGP opportunities (density of neighbouring fertile females). We conclude that T is involved in sexual courtship displays and mate guarding, but not in gaining EGCs. These findings contrast with those in other species where EGP involves elaborate sexual displays.

Age Factors↗