Large-scale HEV genotype 3 outbreak on New Caledonia Island.

BACKGROUND AND AIMS: Several symptomatic cases of HEV infections were reported to the New Caledonia Island Public Health Service between August and December 2023. This prompted epidemiological and virological investigations to identify the source of infection. APPROACH AND RESULTS: HEV RNA was assessed in symptomatic patients, various food items, and pig farms on the Island. HEV strains were characterized by sequencing. A seroprevalence study was also conducted on asymptomatic blood donors before and after the outbreak. One hundred twenty-seven symptomatic cases were reported. Hospitalization was required for 29/127 patients (22.8%). Hospitalized patients presented more frequently with comorbidities, including liver and cardiovascular diseases (80.7% vs. 27%, p < 0.01), and 3 persons died (2.3%). Among the 100 HEV RNA-positive samples received at the French National Reference Centre for HEV, viral sequencing was possible for 76 samples. All strains were identified as HEV genotype 3, and 74/76 strains were grouped together (nucleotide identity: 98%-100%). Full-length sequencing indicated a new HEV-3 subtype within HEV-3 subclade abk. Only genotype 3f strains were detected on the Island's pig farms. No food items tested positive for HEV RNA. The seroprevalence of HEV IgG and IgM in blood donors was 9.2% (9/98) and 0%, respectively, in 2020, rising to 17.3% (17/98) and 2% (2/98) in 2024. CONCLUSIONS: Although all previous large-scale epidemics in Asia and Africa were associated with HEV-1 or 2, the New Caledonia outbreak was linked to HEV-3. A high number of symptomatic cases were admitted to the hospital, with a case-fatality rate of 2.3%.

The novel HLA-DQA1*03:01:12 allele identified using next-generation sequencing in a Melanesian individual.

HLA-DQA1*03:01:12 differs from HLA-DQA1*03:01:01:01 by one nucleotide substitution in codon 21 in exon 2.

Enterovirus meningitis in Mayotte French Comoros Island, March-June 2019.

BACKGROUND: Enteroviruses (EV) are the most frequent cause of acute meningitis worldwide, and regularly responsible for outbreaks. Human parechoviruses (PeV) are associated with sepsis and meningitis in young infants. In Mayotte, a French department located in the Comoros archipelago, EVs and PeVs are not part of the routine screening of cerebrospinal fluids (CSFs) of patients with meningitis. Consequently, no data is available on EV or PeV epidemiology. AIM: Assess the need for EV and PeV diagnosis in Mayotte. METHODS: CSFs collected between March and June 2019 from patients addressed to Mayotte Hospital were retrospectively screened for EV and PeV by PCR. If positive for EV, genotyping was attempted. RESULTS: EV and PeV RT-PCR were performed on 122/263 (46%) CSFs (45 adults, 77 children). EV meningitis was diagnosed in 16/77 children (21%) with a median age of 32 days (8-62). One 30-days-aged infant presented with a PeV infection. Fever was reported in 94% cases (16/17), followed by gastrointestinal disorders in 29% cases (5/17). EV genotyping achieved identification for 10/16 (63%) EV-positive samples. Four different EV types were identified: Echovirus 16 (E-16, n = 6), EV-B100 (n = 2), and E-14 and E-18 (n = 1, each). CONCLUSION: EV/PeV prevalence of 14% highlights the importance of implementing this diagnosis which can impact duration of hospitalization and administration of antibiotics thus reducing risk of antimicrobial resistance. Surveillance of circulating EV types is needed to understand the range of enteroviruses detected in meningitis cases in places that have been underrepresented in enterovirus surveillance studies.

A prospective study evaluating congenital CMV infection in Mayotte and La Reunion Islands (France).

OBJECTIVES Congenital cytomegalovirus infection (cCMV) affects around 3400 newborns each year in France, of whom 700 will develop sequelae, primarily sensorineural hearing loss. Our objectives were (1) to evaluate incidence of cCMV in two French departments located in the Indian Ocean: Mayotte and La Reunion, and (2) evaluate interest and feasibility/acceptability of universal screening of cCMV at birth. MATERIAL AND METHODS We implemented a universal neonatal CMV screening in Mayotte during 7 months in 2019 and in La Reunion during one month in March 2020. Saliva swabs were collected in the first three days of life, and tested for CMV DNA by PCR. A short survey allowed evaluating whether this screening is acceptable and feasible. RESULTS: A total of 1026 newborns were screened: 854 in Mayotte and 172 in La Reunion. In Mayotte, cCMV incidence was evaluated at a minimum of 1.6 % (95 % CI 0.94-2.81). In La Reunion, cCMV incidence was evaluated at a minimum of 1.2 % (95 % CI -0.20-4.57). All cCMV infants were born to mothers with non-primary CMV infection. Only 0.7 % parents refused the screening. CONCLUSIONS cCMV incidence in Mayotte and La Reunion is higher than in metropolitan France. This diagnosis should not be overlooked, especially since the time dedicated to screening and its feeling by the parents seem to be acceptable.