Relationships Between Clinico-Epidemiological Patterns of Invasive Meningococcal Infections and Complement Deficiencies in French South Pacific Islands (New Caledonia).

PURPOSE: Invasive Meningococcal Disease (IMD) is three fold more common in New Caledonia (NC) than in metropolitan France and many IMD cases (35.7%) are due to Y and W135 serogroups. The purpose of our study was to identify IMD risk factors in NC. METHODS: A retrospective study of all IMD cases that occurred in NC between 2005 and 2011 was conducted. Socio-environmental, clinical and biological data were collected. A search for immune deficiency was proposed to all cases. IMD presentation and outcome were compared according to meningoccal serogroups and the complement deficiency status (C-deficiency). RESULTS: Sixty-six sporadic IMD cases (29 B serogroup, 20 Y or W135, 6 C, 1 A, 10 unknown) occurred in 64 patients often <24 years-old and of Melanesian origin. Five patients died (7.8%). No socio-environmental risk factors were identified. No asplenia, HIV infection or immunoglobulin deficiencies were found. Two patients had diabetes and 28 of 53 (52.8%) patients had C-deficiency including 20 (71.4%) cases of late complement component deficiency. Patients with C-deficiency were mainly Melanesian (92.8%) originating from the Loyalty Islands (62.1%). They were mostly infected with Y/W135 (42.9%) or B serogroups (32.1%). They often developed later and more severe disease than patients without C-deficiency (need for intensive cares in 60% versus 28.0% of cases, p = 0.01). CONCLUSIONS: A high prevalence of C-deficiency in the Melanesian population may explain epidemiological and clinical features of IMD in NC. Our results imply an adaptation of meningococcal vaccine strategies in NC.

Divergent KSHV/HHV-8 subtype D strains in New Caledonia and Solomon Islands, Melanesia.

BACKGROUND: KSHV/HHV-8 is the etiological agent of Kaposi's sarcoma, primary effusion lymphoma and most multicentric Castleman's disease cases. KSHV exhibits a high genetic variability comprising five genotypes (A-E). Few data are yet available concerning the situation of KSHV, its genetic variability and the associated diseases in Melanesia. OBJECTIVES: We performed a study on 626 natives Melanesians from New Caledonia and Vanikoro Island to evaluate KSHV seroprevalence and characterize molecularly the viral strains. STUDY DESIGN: Plasma from 343 males and 283 females (age range: 15-86 years, mean age: 60) were tested for KSHV latent antibodies by an immunofluorescence assay (IFA) using BC-3 cells. DNAs extracted from peripheral blood buffy-coat of KSHV seropositive individuals were amplified to obtain a 737-bp fragment of the ORF-K1 gene. Phylogenetic analyses were then performed. RESULTS: Among 626 samples, 148 were IFA positive (dilution≥1:80). The overall seroprevalence was 23.6% (25.2% in New Caledonia, 17.5% in Vanikoro). Fifteen (8 men and 7 women, mean age 69 years) out of 148 DNA samples were found PCR positive. All ORF-K1 sequences belonged to KSHV genotype D. A geographic clustering according to the island of origin of KSHV infected persons was clearly observed with sequences from New Caledonia clustering with most Vanuatu strains. CONCLUSIONS: New Caledonia and Vanikoro are endemic for KSHV with a high diversity of genotype D variants. These strains were probably introduced into New Caledonia during multiple waves of migrations of Melanesian and Polynesian individuals that have colonized this archipelago.

Influenza A(H1N1)2009 in the French Pacific territories: assessment of the epidemic wave during the austral winter.

The three French territories in the Pacific (New Caledonia [NC], French Polynesia [FP] and Wallis and Futuna [WF]) have been affected by an outbreak of influenza A(H1N1)2009 during the austral winter of 2009. This wave of influenza-like illness was characterized by a short duration (approximately 8 weeks) and high attack rates: 16-18% in NC and FP, 28% in Wallis and 38% in Futuna. The number of infected patients requiring hospitalization in critical care services and the number of deaths were, respectively, 21 and 10 in NC and 13 and 7 in FP (none in WF). Diabetes, cardiac and pulmonary diseases, obesity in adults, neuromuscular diseases in children, and Oceanic origin were frequently observed among severe cases and deaths. A significant proportion of the population remains susceptible to A(H1N1)2009, making the occurrence of a second wave likely. A state of preparedness and control efforts must be implemented, based on preventive measures (immunization), as well as combined clinical and virological surveillance and health organization.