Incidence of white muscle disease, a viral like disease associated with mortalities in hatchery reared postlarvae of the giant freshwater prawn Macrobrachium rosenbergii (De Man) from the south east coast of India

Incidence of post-larval mortalities of 30- 100% was reported from commercial freshwater prawn Macrobrachium rosenbergii (De Man) hatcheries in Andhra Pradesh and Tamil Nadu (south-eastern states of India) since 2001. Infec ted postlarvae (PL) exhibited clinical symptoms with lethargy, anorexia and whitening of abdominal muscles and the disease was identified as white muscle disease (WMD)

Effect of temperature and salinity on the infectivity pattern of white spot syndrome virus (WSSV) in giant tiger shrimp Penaeus monodon (Fabricius, 1837)

White spot disease (WSD) caused by the lethal white spot syndrome virus (WSSV) continues to be the major cause of mortality among farmed tiger shrimp in India and elsewhere, resulting in an annual loss of about 4-6 billion US$. Among the environmental variables, temperature and salinity of the rearing water are considered to be major triggering factors for white spot disease outbreak. In order to characterise the effect of salinity and temperature on the pathogenecity of WSSV infection in giant tiger shrimp Penaeus monodon, a laboratory challenge study was conducted at different levels of temperature (16, 25, 27, 28, 30, 32 and 36 ºC) and salinity (0.5, 5, 10, 15, 30 and 45 g l-1) with virulent white spot syndrome virus. Significant influence of temperature (p<0.05) on the percentage mortality and time until death of shrimp affected by the virus was observed, whereas salinity did not show any effect. Significantly higher survival rate was recorded in animals exposed at 32 ºC (37%) and 36 ºC (14%), 21 days post-challenge (dpc). All the shrimp challenged at other temperature levels, however, died after 21 dpc. These results demonstrated preference of WSSV for lower temperatures and higher survival in temperature ranges of 32 ºC to 36 ºC. The present observation may help to develop a management option to control the WSSV inflicted mortalities by selecting favorable hyperthermic rearing conditions for the shrimp

Involvement of Enterobacter cloacae in the mortality of the fish, Mugil cephalus

Enterobacter cloacae, an enteric bacterium that belongs to the family Enterobacteriaceae, is widely distributed in nature. It is found in faeces of humans and animals, water, soil, plants, plant materials, insects and dairy product

Proteomic and functional analyses of the virion transmembrane proteome of cyprinid herpesvirus 3

Virion transmembrane proteins (VTPs) mediate key functions in the herpesvirus infectious cycle. Cyprinid herpesvirus 3 (CyHV-3) is the archetype of fish alloherpesviruses. The present study was devoted to CyHV-3 VTPs. Using mass spectrometry approaches, we identified 16 VTPs of the CyHV-3 FL strain. Mutagenesis experiments demonstrated that eight of these proteins are essential for viral growth in vitro (ORF32, ORF59, ORF81, ORF83, ORF99, ORF106, ORF115, and ORF131), and eight are non-essential (ORF25, ORF64, ORF65, ORF108, ORF132, ORF136, ORF148, and ORF149). Among the non-essential proteins, deletion of ORF25, ORF132, ORF136, ORF148, or ORF149 affects viral replication in vitro, and deletion of ORF25, ORF64, ORF108, ORF132, or ORF149 impacts plaque size. Lack of ORF148 or ORF25 causes attenuation in vivo to a minor or major extent, respectively. The safety and efficacy of a virus lacking ORF25 were compared to those of a previously described vaccine candidate deleted for ORF56 and ORF57 (Δ56-57). Using quantitative PCR, we demonstrated that the ORF25 deleted virus infects fish through skin infection and then spreads to internal organs as reported previously for the wild-type parental virus and the Δ56-57 virus. However, compared to the parental wild-type virus, the replication of the ORF25 deleted virus was reduced in intensity and duration to levels similar to those observed for the Δ56-57 virus. Vaccination of fish with a virus lacking ORF25 was safe but had low efficacy at the doses tested. This characterization of the virion transmembrane proteome of CyHV-3 provides a firm basis for further research on alloherpesvirus VTPs. IMPORTANCE Virion transmembrane proteins play key roles in the biology of herpesviruses. Cyprinid herpesvirus 3 (CyHV-3) is the archetype of fish alloherpesviruses and the causative agent of major economic losses in common and koi carp worldwide. In this study of the virion transmembrane proteome of CyHV-3, the major findings were: (i) the FL strain encodes 16 virion transmembrane proteins; (ii) eight of these proteins are essential for viral growth in vitro; (iii) seven of the non-essential proteins affect viral growth in vitro, and two affect virulence in vivo; and (iv) a mutant lacking ORF25 is highly attenuated but induces moderate immune protection. This study represents a major breakthrough in understanding the biology of CyHV-3 and will contribute to the development of prophylactic methods. It also provides a firm basis for the further research on alloherpesvirus virion transmembrane proteins

Microneedle array delivered recombinant coronavirus vaccines: Immunogenicity and rapid translational development

Background: Coronaviruses pose a serious threat to global health as evidenced by Severe Acute Respiratory Syndrome (SARS), Middle East Respiratory Syndrome (MERS), and COVID-19. SARS Coronavirus (SARS-CoV), MERS Coronavirus (MERS-CoV), and the novel coronavirus, previously dubbed 2019-nCoV, and now officially named SARS-CoV-2, are the causative agents of the SARS, MERS, and COVID-19 disease outbreaks, respectively. Safe vaccines that rapidly induce potent and long-lasting virus-specific immune responses against these infectious agents are urgently needed

Longitudinal disease studies in small-holder black tiger shrimp (Penaeus monodon) farms in Andhra Pradesh, India. I. High prevalence of WSSV infection and low incidence of disease outbreaks in BMP ponds

A longitudinal study was conducted from January to August 2005 in small-holder black tiger shrimp (Penaeus monodon) ponds in the West Godavari District of Andhra Pradesh, India (16°25′ N, 81°19′ E). The study involved 457 ponds owned by low-income farmers participating in a better management practice (BMP) programme. Disease outbreaks occurred in 16.6% of ponds. There was significant spatial clustering of disease outbreaks with 31 (40.8%) of the 76 recorded disease outbreaks occurring in a single village block. Bivariate analysis indicated a 1.6-fold higher likelihood of disease outbreaks from nursery-stocked ponds but this was not significant in multivariate analysis due to the confounding effect of pond location. There was evidence of increasing prevalence of WSSV infection during grow-out. WSSV was detected in 5.9% of 119 batches of postlarvae tested at stocking, 38.2% of 34 juvenile batches collected at the time of transfer to grow-out ponds, and 47.0% of 336 pond stock tested at normal harvest or crop failure. WSSV was detected in 43 of 59 (72.9%) disease outbreak ponds tested and 115 of 277 (41.5%) non-outbreak ponds tested. Heavy WSSV infection was detected at harvest in 116 of the 336 (34.5%) of the ponds tested, including 78 ponds for which no outbreak was recorded. Duration of crop was recorded for 431 ponds with a mean of 117.0 days and a range of 20 to 176 days. Median duration was significantly shorter for disease outbreak ponds (68.5 days) compared to nonoutbreak ponds (119.0 days). Duration of crop also varied according to WSSV detection levels at harvest, with median duration for ponds classified as heavy WSSV infection (108.5 days) significantly shorter than for ponds classified as either light WSSV infection (116.0 days) or WSSV-negative (116.5 days). The study indicated a high risk of WSSV infection during grow-out but a relatively low incidence of disease despite a high prevalence of heavy WSSV infection in non-outbreak ponds

Enteric coronavirus in ferrets, the Netherlands

No abstract foun

Middle East respiratory syndrome coronavirus specific antibodies in naturally exposed Israeli llamas, alpacas and camels

Thus far, no human MERS-CoV infections have been reported from Israel. Evidence for the circulation of MERS-CoV in dromedaries has been reported from almost all the countries of the Middle East, except Israel. Therefore, we aimed to analyze MERS-CoV infection in Israeli camelids, sampled between 2012 and 2017. A total of 411 camels, 102 alpacas and 19 llamas' sera were tested for the presence of antibodies to MERS-CoV. Our findings indicate a lower MERS-CoV seropositivity among Israeli dromedaries than in the surrounding countries, and for the first time naturally infected llamas were identified. In addition, nasal swabs of 661 camels, alpacas and lamas, obtained from January 2015 to December 2017, were tested for the presence of MERS-CoV RNA. All nasal swabs were negative, indicating no evidence for MERS-CoV active circulation in these camelids during that time period

Deletion variants of middle east respiratory syndrome coronavirus from humans, Jordan, 2015

We characterized Middle East respiratory syndrome coronaviruses from a hospital outbreak in Jordan in 2015. The viruses from Jordan were highly similar to isolates from Riyadh, Saudi Arabia, except for deletions in open reading frames 4a and 3. Transmissibility and pathogenicity of this strain remains to be determined