CU vaccine gumboro
22 Nov 2001

Granma International - Havana - NEXT year could see the registration and marketing of a Cuban anti-Gumboro vaccine - developed with recombinant DNA technology by experts at the Biological Pharmaceutical Laboratories (LABIOFAM) - which has received two international awards this year. Antonio Casas, director of LABIOFAM's associated company Virological Products, told Granma International that the vaccine project - the only one of its type in the country and the world - has been patented in Cuba's Patents and Trademarks Office. The disease of viral origin, discovered in 1962 in the U.S. town of Gumboro, affects the immunological system of chickens (by destroying B lymphocytes), leading to a high mortality rate worldwide and the consequent economic losses. Given the stability of the virus responsible for the disease, immunization is the only form of control. Mayelin Paneque, the biochemistry expert leading the project, told Granma International that with Gumboro DNA - the product's provisional name - the immune response lasts longer than that of conventional vaccines currently produced in the world, based on reduced strains of the virus. "Inoculation with specific genes means that antibodies against the virus are being "continually" produced within the organism, thus releasing an immunological response," she explained. Paneque highlighted that with this vaccine there is no need to avoid maternal antibodies that neutralize immunization, as is the case with established vaccines which require serological monitoring to determine an adequate immunization period. Cuba has Gumbolab - a vaccine taken from 11-day-old incubated embryos free of specific pathogens - from which LABIOFAM produces more than 60 million doses per year, administered orally in chickens' drinking water. It is well known that conventional vaccines offer no protection against new strains of the disease that have appeared from the 1980's onwards. Some of the more virulent strains were found in Europe, with so-called variants discovered in the United States.  Gumboro was reported on the island for the first time in 1983; although no variant strains exist, the Cuban company set to work discovering a product also capable of offering protection against them. Research began in 1996; experts first had to characterize all the strains circulating in the country in order to develop a vaccine. That labor was undoubtedly worthwhile. This year the Cuban project received the award for the best pathological undertaking at the 17th Latin American Poultry Farming Congress in Guatemala, and the Biovei prize from the Tarragona Veterinary Medical College, Spain. In 2000, it was awarded the Technical Youth Brigades national prize, whilst also winning the best research work award at the 16th Latin American Poultry Farming Congress in Peru, in 1999.  However this is not the first, nor will be the last, vaccine to be produced by this group that provides 90% of the island's veterinary medicine needs. Antonio Casas confirmed that LABIOFAM has developed 14 viral vaccines to protect sheep, goats, horses and poultry, producing "between two to three billion doses per year. The center is working on other research projects in order to substitute imports costing "tens of millions of dollars, without counting the risks implied by foreign biological products entering Cuba, taking into account the international situation," he pointed out. Casas commented that by the end of this year LABIOFAM should have a vaccine against infectious equine anemia registered for production and marketing in Latin America and the Caribbean. Unique in the world, it has been developed by specialists from China's Harbin Institute of Veterinary Research. He added that cooperative work with the Harbin Institute has been going into this project since 1994. Lionel Hernández, who heads the Cuban part of the project, explained that infectious equine anemia - known since 1845 - is caused by a virus from the retroviridae family which, among other symptoms, provokes recurrent fever plus weight and appetite loss. The Cuban expert indicated that even though this disease cannot be transmitted to people it has a high incidence throughout the world with the ensuing economic damage, as animals suffering from the disease are slaughtered. In that context, the vaccine developed in China and used successfully for more than 20 years, is an effective solution for controlling infectious equine anemia. Expert Fredis Lorenzo highlighted that a vaccine against Eastern equine encephalomyelitis is shortly be produced on a industrial scale. This vaccine is a result of technological improvements on traditional methods existing since 1967, guaranteeing high quality, greater biosecurity and savings in raw materials and labor. BHK-21, explained Lorenzo, is obtained from hamster kidney cell cultures, as distinct from conventional vaccines that use "some 60,000 embryonic eggs" in their production. The specialist pointed out that the country produces 500,000 doses of the vaccine annually. This disease, which damages the central nervous system and results in death, can also affect humans. The only form of control is inoculating all horses. Lorenzo also referred to other vaccines produced in the center including one developed on the island in 1992 to combat swine encephalomyocardium, another first for Cuba; the anti-swine leptospirosis vaccine previously imported from the former Soviet Union; and the vaccine against Auiezky disease, a condition affecting hogs' central nervous system that LABIOFAM developed in 1986.  He explained that last year a triple vaccine based on the three above-mentioned ones went into production with the resulting economic and immunization savings. Casas concluded by stating that this year the company is committed to contributing $11,000,000 USD in medicines to the state, pharmacological products that "fulfill all existing international quality control standards."