San José, Costa Rica, since 1956

Threatening Diseases Re-emerge , Irresponsible Antibiotics Use Blamed

While avian flu and the West Nile viruscould reach Costa Rica “at any moment,” thecountry is inadvertently pumping so manyantibiotics into the wild that the country’showler monkeys, and perhaps other animals,are becoming hothouses of antibiotic-resistantbacteria, scientists warned Monday.Newly evolved and newly discovered diseasesare plaguing humanity and its entourage of animals– from pets to livestock – faster than ever before,according to a panel of four scientists from thenation’s two largest universities, the UniversidadNacional (UNA) and the University of Costa Rica(UCR), and the Agriculture Ministry.At the same time, they said, diseases such as tuberculosisare becoming progressively resistant to antibioticsand re-emerging from the history books as crediblepublic health threats.“Through most of the second half of the 20th century,scientific advances diminished the prevalence of diseases,”said Gaby Dolz, professor of UNA’s veterinaryschool. However, “in the past few years scientists havetried to explain the sudden increase of new diseases andinfections and the re-emergence of diseases we had IN Costa Rica, certain medical andagricultural practices may be breedingantibiotic-resistant bacteria, according toFernando García, a microbiologist atUCR’s Center for Tropical DiseaseResearch.As a member of Monday’s panel,García warned such resistance could be anew trend in disease evolution.“In 1942, doctors began to use antibioticstherapeutically,” he said. “Now, only60 years later, many of the drugs are notuseful.”Tuberculosis has re-emerged, newlyresistant to some antibiotics. How did itand other diseases develop their defensesso readily? The blame falls not just on the“impressive lack of discipline” in antibioticsuse in hospitals, he said, the drugs arealso used recklessly on crops and in livestock.Hospitals are colonies of antibiotics resistantbacteria that latch onto their hosts– the patients – and are transmitted to thepatients’ friends and families when they gohome, García said. Because Costa Ricanhospitals don’t treat their wastewater, thelarge amount of antibiotics in patients’urine are released into the country’s rivers,where they can breed resistant bacteria inwild animals.FIELDS and livestock have the sameeffect. Three kinds of antibiotics are usedin agriculture, two of which are approvedfor that kind of application by the U.S.Environmental Protection Agency (EPA)and one of which, called gentamicine, isnot EPA approved, but is used here.“The EPA respected the impact (gentamicine)has in medicine – it’s very usefulfor the treatment of certain infections. InCosta Rica, the body that authorized its usewas the Agriculture Ministry after consultingthe Health Ministry,” García told TheTico Times.The only right move to make fromhere, he said, is to discontinue its use inagriculture.“One policy on antibiotic use is to haveto no policy. That’s the current policy inCosta Rica,” García said. “The only strategyfrom a public health point of view is todiminish the use of antibiotics.”Limiting their use on people impliesvaccinations and cleanliness, he said.THE irresponsible use of antibioticsmay have already taken its toll. Garcíarecently led research on howler monkeysin Costa Rica in which scientists foundthe monkeys carry antibiotic-resistantbacteria of human origin. This couldmean that not only antibiotics, but alsohuman diseases, are leaking into wildspaces.The study did not determine how thisdevelopment could affect humans, but,García, said, the possibility that itcould indirectly affect either human ormonkey health is one that “we cannotdiscard.”Most of the diseases that havescourged humanity for decades comefrom the wild, the panel agreed. HIV, thevirus that causes AIDS, is thought tohave originated in African chimpanzeesand crossed into human bloodstreamsthrough a zoonosis – a viral transferbetween species.According to the U.S. Centers forDisease Control, there is evidence thatSevere Acute Respiratory Syndrome(SARS) crossed over to people frominfected wild and domestic animals inChina, and that African rodents wereresponsible for the transmission of theinfamous Ebola virus.In fact, Dolz said as many as 75% ofnew and newly discovered diseases havewild origins. They become problems forpeople often because people intrude onwild areas or mishandle wild animals.THE rise in infections and outbreaksin the last several decades has its roots inmedical advances and population growth,the panel agreed. Dolz used the Marburgvirus, a hemorrhagic fever-inducing viruslike Ebola, as an example of scientificstudy gone wrong. The virus first began toravage the western world in 1967 whenscientists in Marburg and Frankfurt,Germany, and Belgrade, Yugoslavia (nowSerbia), simultaneously developed hemorrhagicfevers after exposure to Africangreen monkeys they imported for researchon a polio vaccine.The Nipah virus, first detected inMalaysia in 1999, is an example of a diseasepeople brought on themselves whengrowing populations expanded into wildareas. The World Health Organizationreports that fruit bats likely transmit thedisease to livestock, where it can infectpeople.Habitat change, such as climaticchanges and deforestation, causes shifts inwild animal populations, which can putthem in contact with humans for the firsttime – another means of transmitting disease,Dolz said.SHE also blames the rise of internationaltravel by both people and theirdomestic animals. Diseases that wouldhave stayed in isolated regions in the pastare now distributed throughout the worldby jet, she said.Through viral evolution, another factor,diseases like the flu, distemper, SARSand others change genetically and resistmedical treatments that worked on theirformer incarnations, she said.West Nile virus and avian flu havebeen reported in Mexico and El Salvador,and “it’s just a matter of time before theycome down here,” she told The TicoTimes.She attributes Costa Rica’s avoidanceof the diseases thus far to “a lot of luck”and the Agriculture Ministry’s portcontrols. The country has careful safeguardsin place at its ports and borders,she said.Last year, at the height of the avian fluscare, Alejandro Hernández, director of theCosta Rican Organization of PoultryFarmers, said Costa Rica’s defense measuresagainst the virus are the mostadvanced in the region (TT, Feb. 13,2004).

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