The microorganism generates a chronic degenerative infection, which causes dwarfism in these crustaceans, causing an economic loss to the producers, without affecting human health when consumed. The specialist of the Immunology and Molecular Biology Laboratory of Cinvestav-Mérida, Rossanna Rodríguez Canul, said that shrimp production in farms is an important source of income for Mexican aquaculturists.

 

But this activity is threatened by infection with infectious hypodermal and hematopoietic necrosis virus (IHHNV) and white spot virus (WSSV), which negatively affect the health of crustaceans and cause serious economic problems. She mentioned that in view of this situation she has carried out studies together with other institutions in the country, both in the Pacific and the Atlantic, with the purpose of observing the health conditions of farmed and wild shrimp.

 

In addition, the laboratory monitors the northern coast of the Yucatan Peninsula and has found that two species of wild shrimp are infected with IHHNV in a Yucatan port. Therefore, she suggests the need to carry out more exhaustive epidemiological studies on these viruses in the Gulf of Mexico, she said.

 

 

She expressed that the IHHNV and WSSV viruses are of the DNA type, but the second is highly pathogenic and lethal, it has been studied a lot in the world, but there is still no cure or something that can achieve its eradication. When it infects shrimp, mainly farmed ones, it can wipe out an entire batch of crustaceans within 10 days. Instead, the IHHNV virus generates a chronic degenerative infection that gradually deteriorates the health of the shrimp. Depending on the species, it can be lethal, but the one that completely kills is the Litopenaeus stylirostris or blue shrimp.

 

The L. vannamei variety or white shrimp, a species that is farmed almost everywhere, mainly in Mexico, is not killed by the virus, but it does affect its immune and physiological systems, causing dwarfism or Rostrum Deformity Syndrome (RDS)., with which the shrimp does not reach commercial size. She explained that this dwarfing effect on decapods causes huge economic losses to aquaculturists, because they cannot sell or export them as top quality.

 

 

IHHNV infection causes a shrimp not to reach its normal size, 15 to 20 centimeters, in a period of 10 months, and causes crustaceans to only develop a size of between four and five centimeters, Rodríguez Canul stressed. The researcher pointed out that both the white spot virus and the IHHNV need a cell to replicate and live.

 

Both use the cell's DNA machinery, begin to reproduce, and spread to other cells; At the moment there is no cure or treatment to eliminate it. If the human being or another higher vertebrate consumes a shrimp infected with these viruses, nothing happens to them, because they are harmless to them.

 

 

Most of the Litopenaeus vannamei white shrimp farms are concentrated in the Mexican Pacific, mainly in Sonora, Sinaloa and Nayarit, but there are reports of the presence of WSSV and IHHNV in farms and in wild shrimp. For the Gulf of Mexico there are no reports of WSSV; however, there is only one report of IHHNV in farms in Tamaulipas, an entity that concentrates the largest number of farms in the area.

 

The finding of IHHNV infection of wild shrimp in a Yucatan port has several interpretations: it is likely that the virus was spread through farm waste. But, it is also considered that it became enzootic, that is, it is already part of the fauna and is found in marine currents, from where it has spread among the fauna, in the first instance in the wild shrimp area where they cohabit with farmed ones. .

 

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