Pig delta coronavirus (PDCoV)

The pig delta coronavirus (PDCoV) overview

Pig delta coronavirus (Porcine deltacoronavirus, PDCoV) is a kind of important swine intestinal pathogens, belong to the coronavirus family, can cause acute diarrhea, vomiting and dehydration of newborn piglets, and even death. This virus is the earliest discovered in Hong Kong, and then are covered in many countries and regions in the world. Because of its high genetic diversity, and between different lineages and frequent within the restructuring of the phenomenon, which has increased the complexity of the research and prevention and control difficult. In addition, it also can infect many kinds of mammals, including humans, it puts forward a new challenge for prevention and control of zoonoses.

Pathogenic characteristics

PDCoV virus particles for single strands with posterior capsule is chain RNA virus, the virus encoded protein varied, including spike protein (S) and membrane protein (M protein), core-shell protein (N protein), etc. Methods, viral replication of the virus into the host cell process and evade the host immune system mechanism is an important part of its pathogenic characteristics. Studies have shown that PDCoV certain proteins such as S protein may be related to the host cell receptor, promoting viruses and spread.

epidemic

Reported for the first time since 2014, PDCoV broke out in several countries around the world, especially in Asia and North America caused significant economic loss in the pig industry. Virus is spread by the fecal-oral route, infection rates in different regions and time differences, but on the whole, especially in areas where no effective prevention and control measures infection rate is higher.

Route of transmission

PDCoV by infected animals is the main route of transmission of environmental pollution of excrement and urine, and then spread through the way such as food and water to healthy animals. The virus can also spread through contact with infected animals or their waste. In the intensive aquaculture environment, particularly high speed and efficiency for the spread of the virus.

clinical signs and symptoms

Animals infected PDCoV often exhibit symptoms, such as acute diarrhea, vomiting and dehydration. In newborn piglets, these symptoms are particularly serious, often leading to death. The symptoms of adult animals relatively light, but also become infected. The determination of the severity of the clinical symptoms and viral load can help assess the risk of the seriousness of the epidemic and the spread of the virus.

Pathological changes

Virus infection caused by pathological changes mainly in the digestive tract, especially in the small intestine. Pathological changes including intestinal villus atrophy, intestinal epithelial cell necrosis and inflammation, etc. These changes affect the intestinal absorption capacity, leading to the emergence of diarrhea and other symptoms.

Diagnostic methods

Diagnosis mainly depends on the combination of laboratory tests and clinical symptoms. Commonly used detection methods include reverse transcription-polymerase chain reaction (rt-pcr), real-time fluorescent quantitative PCR (RT - qPCR), ring mediated isothermal nucleic acid amplification technologies (RT - LAMP), etc. These methods can be used to detect the virus nucleic acid, which confirmed the infection. In addition, ELISA and serological detection method can be used to detect virus antibody in the body to aid diagnosis.

Prevention and control measures

There are currently no effective vaccine against PDCoV or drugs. The main prevention and control measures including improving the biological safety of farms, implementing strict cleaning and disinfection procedures, restrict the flow of personnel and items, to ensure that the animal welfare and health monitoring. In the case of the outbreak, isolation and culling control measures should be taken to prevent further spread of the virus. In addition, the need for scientific research to explore a more effective prevention and control strategy.

conclusion

To sum up, the pig delta coronavirus is a high genetic diversity and widely popular trend of pathogens, can bring significant economic impact to pig industry. Although there is currently no specific and vaccines, but through ascension, safety measures and optimized diagnosis method, can effectively control and reduce the spread of the virus. Future needs more research to further understand the basic biology of virus and pathogenic mechanism, in order to develop effective prevention and control measures.