A novel rhabdovirus isolated from the straw-colored fruit bat Eidolon helvum, with signs of antibodies in swine and humans.

UNLABELLED: Bats have been implicated as reservoirs of emerging viruses. Bat species forming large social groups and roosting in proximity to human communities are of particular interest. In this study, we sampled a colony of ca. 350,000 individuals of the straw-colored fruit bat Eidolon helvum in Kumasi, the second largest city of Ghana. A novel rhabdovirus (Kumasi rhabdovirus [KRV]) was isolated in E. helvum cell cultures and passaged to Vero cells as well as interferon-competent human and primate cells (A549 and MA104). Genome composition was typical for a rhabdovirus. KRV was detected in 5.1% of 487 animals, showing association with the spleen but not the brain. Antibody prevalence was 11.5% by immunofluorescence and 6.4% by plaque reduction virus neutralization test (PRNT). Detection throughout 3 sampling years was pronounced in both annual wet seasons, of which only one overlaps the postparturition season. Juvenile bats showed increased viral prevalence. No evidence of infection was obtained in 1,240 female mosquitos (6 different genera) trapped in proximity to the colony to investigate potential vector association. Antibodies were found in 28.9% (5.4% by PRNT) of 107 swine sera but not in similarly large collections of sheep, goat, or cattle sera. The antibody detection rate in human subjects with occupational exposure to the bat colony was 11% (5/45 persons), which was significantly higher than in unexposed adults (0.8% [1/118]; chi square, P < 0.001). KRV is a novel bat-associated rhabdovirus potentially transmitted to humans and swine. Disease associations should be investigated. IMPORTANCE: Bats are thought to carry a huge number of as-yet-undiscovered viruses that may pose epidemic threats to humans and livestock. Here we describe a novel dimarhabdovirus which we isolated from a large colony of the straw-colored fruit bat Eidolon helvum in Ghana. As these animals are exposed to humans and several livestock species, we looked for antibodies indicating infection in humans, cattle, swine, sheep, and goats. Signs of infection were found in swine and humans, with increased antibody findings in humans who are occupationally exposed to the bat colony. Our data suggest that it is worthwhile to look for diseases caused by the novel virus in humans and livestock.

No Evidence of Gouléako and Herbert Virus Infections in Pigs, Côte d'Ivoire and Ghana.

A recent report suggested that 2 novel bunyaviruses discovered in insects in Côte d'Ivoire caused lethal disease in swine in South Korea. We conducted cell culture studies and tested serum from pigs exposed to mosquitoes in Côte d'Ivoire and Ghana and found no evidence for infection in pigs.

Discovery of a unique novel clade of mosquito-associated bunyaviruses.

Bunyaviruses are the largest known family of RNA viruses, infecting vertebrates, insects, and plants. Here we isolated three novel bunyaviruses from mosquitoes sampled in Côte d'Ivoire, Ghana, and Uganda. The viruses define a highly diversified monophyletic sister clade to all members of the genus Orthobunyavirus and are virtually equidistant to orthobunyaviruses and tospoviruses. Maximal amino acid identities between homologous putative proteins of the novel group and orthobunyaviruses ranged between 12 and 25%. The type isolates, tentatively named Herbert virus (HEBV), Taï virus (TAIV), and Kibale virus (KIBV), comprised genomes with L, M, and S segments of about 7.4 kb, 2.7 kb, and 1.1 kb, respectively. HEBV, TAIV, and KIBV encode the shortest bunyavirus M segments known and did not seem to encode NSs and NSm proteins but contained an elongated L segment with an ∼500-nucleotide (nt) insertion that shows no identity to other bunyaviruses. The viruses replicated to high titers in insect cells but did not replicate in vertebrate cells. The enveloped virions were 90 to 110 nm in diameter and budded at cellular membranes with morphological features typical of the Golgi complex. Viral RNA recovered from infected cells showed 5'-terminal nontemplated sequences of 9 to 22 nt, suggestive of cap snatching during mRNA synthesis, as described for other bunyaviruses. Northern blotting identified RNA species of full and reduced lengths, suggested upon analogy with other bunyaviruses to constitute antigenomic-sense cRNA and transcript mRNAs, respectively. Functional studies will be necessary to determine if this group of viruses constitutes a novel genus in the bunyavirus family.

A randomized trial on effectiveness of artemether-lumefantrine versus artesunate plus amodiaquine for unsupervised treatment of uncomplicated Plasmodium falciparum malaria in Ghanaian children.

BACKGROUND: Numerous trials have demonstrated high efficacy and safety of artemisinin-based combination therapy (ACT) under supervised treatment. In contrast, effectiveness studies comparing different types of ACT applied unsupervised are scarce. The aim of this study was to compare effectiveness, tolerability and acceptance of artesunate plus amodiaquine (ASAQ) against that of artemether-lumefantrine (AL) in Ghanaian children with uncomplicated Plasmodium falciparum malaria. METHODS: A randomized open-label trial was conducted at two district hospitals in the Ashanti region, Ghana, an area of intense malaria transmission. A total of 246 children under five years of age were randomly assigned to either ASAQ (Arsucam) or AL (Coartem). Study participants received their first weight-adjusted dose under supervision. After the parent/guardian was advised of times and mode of administration the respective three-day treatment course was completed unobserved at home. Follow-up visits were performed on days 3, 7, 14 and 28 to evaluate clinical and parasitological outcomes, adverse events, and haematological recovery. Length polymorphisms of variable regions of msp1 and msp2 were determined to differentiate recrudescences from reinfections. Acceptance levels of both treatment regimens were assessed by means of standardized interviews. RESULTS: Adequate clinical and parasitological responses after AL and ASAQ treatment were similar (88.3% and 91.7%, respectively). Interestingly, more late clinical failures until day 28 occurred in AL-treated children than in those who received ASAQ (17.5% and 7.3%, respectively; Hazard Ratio 2.41, 95% CI 1.00-5.79, p < 0.05).Haematological recovery and drug tolerability were not found to be significantly different in both study arms. The acceptance of treatment with ASAQ was higher than that with AL (rank-scores 10.6 and 10.3, respectively; p < 0.05). CONCLUSION: Unobserved AL and ASAQ treatment showed high adequate clinical and parasitological responses, though AL was inferior in preventing late clinical failures.