Latest Research Progress on Porcine High Fever Syndrome

The "high fever syndrome" that first broke out in southern China in the summer of 2006 has not yet subsided, and it is currently the issue of greatest concern to us @#@227@#@ people. Some readers have also called our editorial office to inquire about research progress on the disease! At the "Beijing Animal Husbandry Association Pig Industry Annual Meeting", Academician Chen Huanchun of Huazhong Agricultural University and Professor Yang Hanchun of China Agricultural University were invited to each express their personal views on the currently prevalent "high fever syndrome".

1 Epidemic situation

First, geographically it spread from south to north and from east to west, eventually sweeping the whole country. Pigs of all ages and breeds are susceptible; it occurs easily in farm households and small specialized households, and also occurs in medium and large pig farms.

2 Clinical symptoms

The body temperature of sick pigs is all around 40-42 degrees, with clear to purulent nasal discharge, decreased appetite, vomiting, rapid breathing, redness of the whole body, dry and hard feces, and neurological symptoms appearing before death.

3 Necropsy changes

Acute septicemia, poor blood coagulation, subcutaneous gelatinous exudate, pericardial effusion, enlarged and fragile spleen, enlarged kidneys, bladder hemorrhage, laryngeal hemorrhage, pulmonary hemorrhage, pleural effusion, gastric mucosal detachment with extensive hemorrhage, and intestinal mucosal detachment and hemorrhage.

4 Etiological analysis

Regarding the pathogen of this disease, there is currently no definitive conclusion, but based on laboratory research, the two experts each have their own views. First, after laboratory testing, Academician Chen's research group isolated Escherichia coli from the tissue samples of diseased pigs. After drug sensitivity testing, it was found that this Escherichia coli had developed resistance to most drugs. The isolated Escherichia coli, when subjected to animal sensitivity testing, produced symptoms similar to those of clinically diseased pigs, but whether this disease is caused by Escherichia coli still requires further experiments to prove. In addition, Professor Yang's experiments indicated that there may be two possibilities: one is a variant strain of porcine reproductive and respiratory syndrome, and the other is an unknown virus, but he leans more toward the latter. Many legends about this disease (such as influenza, streptococcus, etc.) do not hold up, and Professor Yang explained and ruled them out one by one. However, what this unknown virus is is still unknown and remains to be further studied. The views of these two experts may give us some inspiration, and it is hoped that through the unremitting efforts of experts, a conclusion will be reached in the near future.

5 Prevention and control recommendations

The two experts gave prevention and control recommendations. First, routine disinfection work should be done well. Restrict the movement of personnel, and dead pigs should be deeply buried or incinerated. Second, for diseased pigs, antipyretic drugs should not be used in the early stage; instead, some electrolyte multivitamins can be added to the drinking water, and symptomatic treatment can be adopted after 5-7 days. Autogenous tissue inactivated vaccines can be prepared under the guidance of experts. The situation of each pig farm is different, so treatment must be determined according to specific circumstances. The vast number of farmers should strengthen management and firmly believe that we can certainly overcome this disease!