Innate immune response of snakehead fish to Indian strain of snakehead rhabdovirus (SHRV-In) infection and the infectivity potential of the virus to other freshwater fishes.

A new virus known as snakehead rhabdovirus (SHRV-In) was discovered in South India in striped snakehead (Channa striata) that had hemorrhagic patches and cutaneous ulcerations. The virus is the most potentially harmful pathogen of snakehead because it could cause 100% mortality within 5 days. The goal of the current investigation was to evaluate the infectivity of rhabdovirus in freshwater fishes and to analyze the immune response in snakehead fish after challenge with SHRV-In. The infectivity study of SHRV-In against three freshwater fish such as tilapia, grass carp and loach showed that the virus could not induce mortality in any of them. Snakehead fish challenged with SHRV-In showed significant (p < 0.05) changes in haematological parameters such as red blood cell (RBC), haemoglobin (HGB), haematocrit (HCT), mean corpuscular haemoglobin concentration (MCHC), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), white blood cell (WBC), total platelet (PLT) counts, mean platelet volume (MPV) and immunological markers such as respiratory burst, superoxide dismutase, catalase activity and myeloperoxidase activity at 6, 12, 24 and 48 hpi. Real time PCR was executed to examine the expression profile of innate immune genes such as IRF-7, IL-8 and IL-12 in Snakehead fish at 6, 12, 24 and 48 h post SHRV-In infection. Immune gene expression of IRF-7, IL-8 and IL-12 were up-regulated in the spleen when compared to kidney at 6 and 12 hpi. However, the expression level of all the genes was down-regulated at 24 and 48 hpi. The down regulation of innate immune genes after 24 hpi in these tissues may be the result of increased multiplication of SHRV-In by interfering with the immune signaling pathway.

Occurrence of microplastics in gastrointestinal tracts of planktivorous fish from the Thoothukudi region.

Planktivorous fish are easily susceptible to passive microplastic ingestion during their feeding behaviour and may be transferred along with the marine food web. Hence, the present study was conducted to assess the microplastics prevalence in the planktivorous fish (677 individuals) collected from 2 landing centres in the Thoothukudi, Gulf of Mannar region, South Tamil Nadu, India. The prevalence of microplastics was detected in 118 out of 677 individuals, with a mean abundance and percent occurrence of 1.22 ± 0.47 items/individual and 17%, respectively. The ingestion of microplastics in planktivorous fish was primarily due to their feeding habitat, in which they were prone to the accidental or passive intake of microplastics regardless of the fish's length and body weight. The microplastics abundance was significantly higher in Sardinella gibbosa (1.34 ± 0.56 items/individual), which might be due to their pelagic and planktivorous feeding habitat, highest filtration capacity, presence of closed gill rakers, and also due to the passive ingestion of microplastics as food items. Fibres, blue, and 1 to 2mmsized microplastics were predominant in the guts of Sardinella gibbosa, accounting for 95.74, 47.87, and 46.80%, respectively, whereas in Leiognathus lineolatus, fragments, black, and 1 to 2mmsized microplastics were highly prevalent with 62.96, 72.22, and 79.62%, respectively. The predominance of various shapes (fragments, fibres), sizes (1-2 mm), and colours (blue and black) of microplastics in the guts of fish was influenced by their passive ingestion, ingestion of contaminated planktonic prey, lack of selectivity of prey particles and their resemblance to plankton species. Polypropylene polymers predominated (96.77% and 95.23%) in both fish, followed by polystyrene (3.22% and 4.76%). Furthermore, this study provides baseline data and insists that there is a need for continuous monitoring of the distribution of microplastics.

Correction: Assessment of lung function in successfully treated tuberculosis reveals high burden of ventilatory defects and COPD.

[This corrects the article DOI: 10.1371/journal.pone.0217289.].

Assessment of lung function in successfully treated tuberculosis reveals high burden of ventilatory defects and COPD.

BACKGROUND: Burden, phenotype and risk-factors of lung function defects in successfully treated tuberculosis cases are unclear. METHODS: We performed spirometry with bronchodilators in new drug-sensitive adult (≥18 years) pulmonary tuberculosis cases during the 12 months following successful treatment in India. Airflow obstruction was defined as pre-bronchodilator FEV1/FVC<5th percentile of Global Lung Initiative mixed-ethnicity reference (lower limit of normal [LLN]). Chronic obstructive pulmonary disease (COPD) was defined as post-bronchodilator FEV1/FVC