[Influenza-like illness outbreaks in China during 2017-2018 surveillance season].

Objective: To analyze epidemiological characteristics of influenza-like illness outbreaks in mainland China during 2017-2018 surveillance season, and to provide scientific evidence for developing influenza prevention and control strategies. Methods: We collected the data on reported influenza outbreaks in 2017-2018 surveillance season from China Influenza Surveillance Information System and China Public Health Emergency Management Information System and analyzed the data of laboratory-confirmed influenza-like illness outbreaks by descriptive epidemiological methods. Results: During the surveillance season, a total of 2 398 influenza-like illness outbreaks (with 10 or more incidences in an outbreak) in mainland China were reported, involving 87 084 patients, of which 2 323 were influenza outbreaks, involving 85 531 patients. The reported influenza-like illness outbreaks occurred most frequently from November 2017 to January 2018 in both the southern and northern regions and the highest peaks were in December 2017. During the period 1 850 influenza-like illness outbreaks (77.15%) were reported in the southern region, and 548 influenza-like illness outbreaks (22.85%) were reported in the northern region. The most of the outbreaks occurred in primary, secondary schools and nursery care schools, with a total of 2 210 reports (92.16%). And the majority of the outbreaks involved 10-29 incident cases. The dominant isolated virus strains for the outbreaks were influenza B (1 505 outbreaks, 62.76% of all the outbreaks). Conclusion: Seasonality of influenza outbreaks were observed in mainland China during 2017-2018 surveillance season and the reported influenza outbreaks were most frequently occurred in autumn-winter season and in southern China. Primary, secondary schools and nursery care schools are high-risk places for outbreaks, and the dominant isolated virus strains for the outbreaks were influenza B.

[Clinical characteristics of 6 children with idiopathic interstitial pneumonia].

Objective: To analyze the clinical characteristics and prognosis of 6 children with idiopathic interstitial pneumonia (IIP). Methods: This retrospective study analyzed the clinical manifestations, examinations, treatment and prognosis of 6 children with IIP who were hospitalized in Children's Hospital of Nanjing Medical University from January 2015 to March 2020. Results: Of the 6 children, 2 were males and 4 were females, aged 4.8 to10.6 years. All children had a subacute onset, and presented with cough, shortness of breath and cyanosis. The lung high-resolution CT (HRCT) showed diffuse patchiness in bilateral lung fields in all the children and reticular pattern in 2 cases. Pulmonary function test found moderate to severe mixed defect in 5 children. Lung biopsy was performed in 4 children. All of the 6 children were treated with systemic glucocorticoids, of whom 2 cases had additional inhaled glucocorticoids. Four children were finally diagnosed as cryptogenic organizing pneumonia (COP), whose lung HRCT return to normal in 1-11 months. Two children were finally diagnosed as nonspecific interstitial pneumonia (NSIP), and had long-term residual fibrosis on lung HRCT. The 6 children were followed up for 1 year to 6 years and 5 months after discontinuation of systemic glucocorticoids, and all had no recurrence. Conclusions: The clinical characteristics of IIP in children are subacute onset presented with cough, shortness of breath, cyanosis and diffuse patchiness in bilateral lungs on HRCT. The common subtypes of IIP in children are COP and NSIP. Systemic glucocorticoid is effective for IIP in children and there is a good prognosis overall.

Prevalence of Ehrlichia chaffeensis (Rickettsiales: Rickettsiaceae) in Amblyomma americanum (Acari: Ixodidae) from the Georgia coast and Barrier Islands.

Human monocytic ehrlichiosis is an emerging zoonosis caused by infection with Ehrlichia chaffeensis Anderson, Dawson, Jones & Wilson, which is transmitted to mammals by ixodid ticks. Prevalence of infected ticks and distribution of infection foci indicate relative risk of human exposure to ehrlichiosis and may be influenced by factors such as geographic isolation, human disturbance, and the availability of suitable mammalian reservoir hosts. To test, this, individual and pooled lone star ticks, Amblyomma americanum (L.), were collected from three populations from the Georgia coast (1 mainland site and two barrier islands) and screened for E. chaffeensis. A species-specific, nested polymerase chain reaction (PCR) assay was used to amplify a 572 bp fragment of the E. chaffeensis 16S rRNA gene from infected ticks. PCR product specificity was confirmed by nucleotide sequencing. Our results showed the prevalence of infected ticks to be 0.0% (n = 151), 0.9% (n = 111), and 9.3% (n = 129) for Sapelo Island, St. Catherine's Island, and Fort McAllister, respectively.

Wolbachia endosymbionts in fleas (Siphonaptera).

Intracellular endosymbionts, Wolbachia spp., have been reported in many different orders of insects and in nematodes but not previously in fleas. This is the first conclusive report of Wolbachia spp. within members of the Siphonaptera. Using nested polymerase chain reaction (PCR) targeting of the 16S ribosomal RNA gene, we screened for Wolbachia spp. in fleas collected from 3 counties in Georgia and 1 in New York. The prevalence of Wolbachia spp. detected varied among the 6 different species screened: 21% in the cat flea Ctenocephalides felis (n = 604), 7% in the dog flea C. canis (n = 28), 25% in Polygenus gwyni (n = 8), 80% in Orchopeas howardi (n = 15), 94% in Pulex simulans (n = 255), and 24% in the sticktight flea Echidnophaga gallinacea (n = 101). Wolbachia spp. infection in fleas was confirmed by sequencing positive PCR products, comparing sequenced 16S ribosomal DNA (rDNA) with Wolbachia spp. sequences in GenBank using BLAST search, and subjecting sequence data to phylogenetic analysis. For further confirmation, 16S rDNA-positive samples were reamplified using the wsp gene.

Evolution and phylogenetic utility of the period gene in Lepidoptera.

Evolution and phylogenetic utility of the period gene are explored through sequence analysis of a relatively conserved 909-bp fragment in 26 lepidopteran species. Taxa range from tribes to superfamilies, primarily within the putative clade Macrolepidotera plus near outgroups, and include both strongly established and problematic groupings. Their divergence dates probably range from the late Cretaceous through much of the Tertiary. Comparisons within the same set of closely related species show that amino acid substitutions in period occur 4.9 and 44 times as frequently as they do in two other nuclear genes--dopa decarboxylase and elongation factor-1 alpha, respectively. In contrast, rates of observed synonymous substitution are within 60% of each other for these three genes. Synonymous changes in period approach saturation by the family level, whereas nonsynonymous and amino acid divergences across the Macrolepidoptera are less than half the maximal values reported for this gene. Phylogenetic analyses of period strongly supported groupings at the family level and below. In contrast to previous analyses at this level with other nuclear genes, much of the information lies in nonsynonymous change. Relationships up to the superfamily level were recovered with decreasing effectiveness, and little, if any, signal was apparent regarding relationships among superfamilies. This could reflect rapid radiation of the superfamilies, however, rather than saturation in the period locus; thus, period, in combination with other genes, remains a plausible candidate for approaching the difficult problems of lepidopteran family and superfamily relationships.

Two nuclear genes yield concordant relationships within Attacini (Lepidoptera: Saturniidae).

To extend initial characterizations of their phylogenetic utility, sequences from the nuclear genes for elongation factor-1 alpha (EF-1 alpha) and dopa decarboxylase (DDC) are tested for phylogenetic concordance with each other and with previous morphological evidence within the giant silk moth tribe Attacini (Lepidoptera: Saturniidae). The sampling of DDC is expanded from the 690 basepairs of previous studies to 1051 basepairs in the current study. All nine attacine genera are sampled. EF-1 alpha and DDC agree in the placement of seven of nine genera, with placement of the other two not in strong conflict. Combination of the gene sequences results in a nearly fully resolved tree that is consistent with EF-1 alpha alone and agrees with morphology in five of eight groups. Conflict between molecules and morphology is confined to deeper-level relationships within Attacini, where node support for the molecular hypotheses, but not the morphological hypotheses, is generally very strong. A strong signal is contributed by synonymous substitutions in both genes, and by nonsynonymous change particularly in DDC. The molecular phylogeny supports a revision of attacine biogeography in that neither East Asian nor New World genera form monophyletic groups.

Phylogenetic utility of the nuclear gene dopa decarboxylase in noctuoid moths (Insecta: Lepidoptera: noctuoidea).

Phylogenetic utility for the nuclear gene encoding dopa decarboxylase (DDC), little used in systematics, was recently demonstrated within the noctuid moth subfamily Heliothinae. Here we extend the test of the utility of a 709-bp DDC fragment to deeper levels, analyzing 49 species representing major groups across the superfamily Noctuoidea. Parsimony, distance, and maximum-likelihood analyses recover all or nearly all of a set of "test clades" supported by clear morphological synapomorphies, spanning a wide range of taxonomic levels. DDC also upholds a recent proposal that the Noctuidae are paraphyletic. Nt3 contributes a majority of the signal and recovers the basal split between Notodontidae and all other noctuoids, despite a plateau of nt3 divergence at this level. However, nonsynonymous changes also support groups at all levels, and in contrast to nt3, amino acid divergence shows no plateau. The utility of DDC promises to extend back to the early Tertiary and Cretaceous, a time span for which few suitable genes have been identified.

A new nuclear gene for insect phylogenetics: dopa decarboxylase is informative of relationships within Heliothinae (Lepidoptera: Noctuidae).

The lack of a readily accessible roster of nuclear genes informative at various taxonomic levels is a bottleneck for molecular systematics. In this report, we describe the first phylogenetic application of the sequence that encodes the enzyme dopa decarboxylase (DDC). For 14 test species within the noctuid moth subfamily Heliothinae that represent the previously best-supported groupings, a 690-bp fragment of DDC resolved relationships that are largely concordant with prior evidence from elongation factor-1 alpha (EF-1 alpha), morphology, and allozymes. Although both synonymous and nonsynonymous changes occur in DDC substantially more rapidly than they do in EF-1 alpha, DDC divergences within Heliothinae are below saturation at all codon positions. Analysis of DDC and EF-1 alpha in combination resulted in increased bootstrap support for several groupings. As a first estimate of previously unresolved relationships, DDC sequences were analyzed from 16 additional heliothines, for a total of 30 heliothine species plus outgroups. Previous relationships based on DDC were generally stable with increased taxon sampling, although a two- to eightfold downweighting of codon position 3 was required for complete concordance with the 14-species result. The weighted strict consensus trees were largely resolved and were congruent with most although not all previous hypotheses based on either morphology or EF-1 alpha. The proposed phylogeny suggests that the major agricultural pest heliothines belong to a single clade, characterized by polyphagy and associated life history traits, within this largely host-specific moth subfamily. DDC holds much promise for phylogenetic analysis of Tertiary-age animal groups.