Post by Mech on Mar 18, 2007 0:13:33 GMT -5
Chagas Disease Proliferating -
SoCal Headed To 'Hell'
From Patricia Doyle, PhD
3-16-7
Hello Bert,
Thank you for the article below. Given the fact that illegals from Chagas infected regions are flooding into the US every day, I think that we are going to see a full scale public health crisis in many areas of the US within 7-10 years.
Not only will public health officials become overwhelmed but hospitals will be forced share in this nightmare. I do not see how hospitals and the taxpayers are going to pay the bills of a Chagas-infected population. South and Central America are experiencing this very health crisis now.
Illegals are flocking into the US as 'workers.' There comes a time when a Chagas-infected person becomes unable to work. They then become in need of expensive, permanent medical care. The George Bush 'administration' is so shallow that it hasn't even begun to calculate the price of this 'CHEAP'(?) labor. Those who go onto the chronic stage of Chagas and the heart or colon problems will be unable to work and in need of assistance.
The local US kissing bug species have now demonstrated their ability to carry and vector the T. Cruzi parasite. These triatoma bugs have colonized homes and spread the parasite to local small animal populations and, as we saw in Louisiana, infected a 74 year old victim in her own home in New Orleans. Dogs, armidillos and other small animals serve as reservoir for the disease. This fact should have "served notice" that Chagas is capable of local spreading in the US. Triatoma bugs can be found in southern to mid latitudes in the US. These bugs can be found as far north as Maryland. There have been organ recipients who contracted Chagas from transplants and cases of simple blood transfusion transmission. Health authorities are not screening blood for Chagas.
Public health law would allow the government of the US to close down the border and stop anyone from entering the US from Chagas-infected regions. It is obvious that the US government is more concerned about 'cheap' labor for corporations and business entities than concern for the public health of its citizens. Furthermore, US the taxpayers will, as usual, receive the bill for medical care of Chagas infected, and the cost for Public health trying to deal with a crisis situation in the near future, let's say 2012. And what a bill that's going to be.
I just don't understand why, when we have a chance to stop the Chagas spread in the US, WHY are we not closing the borders? Deporting anyone who is infected with Chagas? This is a matter of the most basic common sense public health. This could just be the next pandemic and we have the power to stop it before it really gets rolling.
Once we allow the genie that is Chagas out of the bottle, there is NO stopping it. The CDC is misleading the public by calling Chagas a disease of poverty and poor living conditions. That's a lie. People from all walks of life and socioeconomic groups throughout Mexico, Central and South America have contracted Chagas. By telling Americans that the disease is one of poverty we are being lulled into believing we are immune to Chagas. Well, kissing bugs can colonize any home.
In Texas, triatoma bugs were found living under patio blocks. 24 of 31 triatomas were found positive for T. Cruzi. We have the vector, we have infected small animals and the vector had colonized homes within the US. This tells me we have a problem; we have conditions locally that favor Chagas spread within the US. Why are we allowing an influx of Chagas-infected people to continue to flood into the US, and do so ILLEGALLY?
2008 Presidential election is not far away. We need to DEMAND that prospective candidates take a stand on illegal immigration. If the current candidates won't take a stand than we need to find an anti-illegal immigration candidate who will.
Patricia
FYI
In the small community of San Benito, Texas (Figure 1), after three pet dogs died from Chagas cardiomyopathy, personnel from the Texas Department of Health, the Cameron County Health Department, Environmental Health Division, and the Centers for Disease Control and Prevention (CDC) inspected the owner's home, garage, and grounds for potential triatomine insect vectors (Figure 2). Blood was drawn from four dogs and two persons residing on the property and tested for antibodies to T. cruzi. A second site approximately 2 miles away was also inspected and blood drawn from three dogs, one of which had been diagnosed as positive for T. cruzi by the original veterinarian. A follow-up serologic survey was conducted to determine the percentage of the stray dogs in Cameron County that would test positive for Chagas disease antibodies. Once a week, samples from stray dogs were shipped to CDC for testing. Each sample was issued an identification number; and information on the animal's location, sex, age, health condition, and size was recorded. Serum specimens were tested for anti-T. cruzi antibodies by indirect immunofluorescence (IIF) (6,7).
Ecologic niches and potential geographic distributions were modeled by using the Genetic Algorithm for Rule-set Prediction (GARP) (8-10). In general, the procedure focuses on modeling ecologic niches, the conjunction of ecologic conditions within which a species is able to maintain populations without immigration. Specifically, GARP relates ecologic characteristics of known occurrence points to those of points randomly sampled from the rest of the study region, seeking to develop a series of decision rules that best summarizes those factors associated with the species' presence. Recently, this method has been used to study the distribution of species complex members and vector-reservoir relationships with respect to Chagas disease (11,12).
Inspection of the residence where the three dogs lived indicated a substantial infestation with the triatomine species T. gerstaeckeri (Figure 3). Triatomines were collected under cement slabs of a backyard patio adjacent to the house and from a garage located approximately 75 feet from the home (Figure 2). Of 31 live triatomines collected, including adults of both sexes and immature stages (i.e., two fifth-instar nymphs), 24 contained T. cruzi-like parasites in their hindgut (Figure 4). Cultures were established from triatomine urine collected from insects that were fed in the laboratory and placed in 1.5-mL microcentrifuge tubes. Approximately 50 µL of clear urine was injected into Novy, Nicolle, & MacNeal culture medium (13). The cultures were positive for parasites confirmed to be T. cruzi, on the basis of morphologic criteria. Inspection of the second residence failed to indicate a bug infestation; however, the pet owner recalled frequently observing both rats (Rattus spp.) and opossums (Didelphis virginiana) on the premises. At the first site, three of the four dogs tested positive for T. cruzi, with titers ranging from 1:128 to 1:256. Neither of the two persons had positive antibody titers against T. cruzi. At the second site, only the previously diagnosed dog tested positive, with a titer of 1:256. The other two dogs tested negative, as did the pet owner. Serum samples from stray dogs from Cameron County, Texas, were tested for antiT. cruzi antibodies. Of 375 dogs tested, 28 (7.5%) were positive by IIF, with titers ranging from 1:32 to 1:512. The sensitivity of this test in humans is 98.8% (pers. comm., Patricia P. Wilkins, Division of Parasitic Diseases, CDC). Because of the low specificity of serologic tests for distinguishing T. cruzi from Leishmania spp., all positive samples were tested for antibodies to L. donovani. A low level of cross-reactivity was observed in 17 of the 28 samples. In each case, however, the titer was 12 dilutions less than the titer to T. cruzi, indicating a primary response to T. cruzi rather than to Leishmania spp. Ecologic niche models for T. gerstaeckeri were developed by using GARP, based on published and unpublished collection records from Mexico and the southwestern United States. The model predicted a distribution for this species that extends from central Mexico, through central Texas, the Texas panhandle, into northern Texas and southeastern New Mexico (Figure 5).
Conclusions
Triatoma gerstaeckeri is considered a sylvatic species, most frequently associated with pack rat (Neotoma spp.) burrows (4). Although individual triatomine insects occasionally invade domestic dwellings throughout the southwestern United States and Mexico (4,5,14), this species has not been reported to colonize these habitats. In this investigation, colonization appears to have occurred, based on the observation of large numbers of bugs, including ones in immature stages. In the Chagas diseaseendemic regions of South and Central America, the primary risk for insect transmission to humans is related to the efficiency with which local vector species can invade and colonize homes, resulting in a domestic transmission cycle for what is otherwise exclusively a zoonotic disease in the southern United States. In disease-endemic countries, higher house infestation rates generally result in a higher risk of transmission. At the first site in south Texas, six dogs either died or tested positive for T. cruzi, and 24 of 31 bugs contained hindgut trypanosomes. These observations demonstrate the existence of a domestic transmission cycle for an insect species that is typically considered a zoonotic vector. Whether this observation represents an isolated case or actually occurs more frequently but remains unrecognized, indicating an emerging public health problem, remains to be determined. The serologic results in stray dogs are very similar to those reported in previous studies from the region, suggesting that the disease is stably maintained in this reservoir host (15,16). The distributional predictions based on GARP models indicate a potentially broad distribution for this species and suggest additional areas of risk beyond those previously reported (14), should this problem become of greater public health concern.
Dr. Beard is chief of the Vector Genetics Section in the Division of Parasitic Diseases, Centers for Disease Control and Prevention. His research focuses on the molecular biology of insect disease vectors and the molecular epidemiology of Pneumocystis pneumonia in HIV-infected persons.
Patricia A. Doyle DVM, PhD Bus
Admin, Tropical Agricultural Economics
Univ of West Indies
Please visit my "Emerging Diseases" message board at: www.emergingdisease.org/phpbb/index.php Also my new website: drpdoyle.tripod.com/ Zhan le Devlesa tai sastimasa Go with God and in Good Health
From: Bert To:
dr_p_doyle@hotmail.com>
Subject: article for you of possible interest from LA Times
Date: Fri, 16 Mar 2007
Hi. I appreciate all the material from you I see on Rense.
I'm sending this article from the Los Angeles Times in case you did not come across it elsewhere.
The Chagas-infected numbers are huge if you consider 1 in 3800 donors means perhaps 2 to 4x that in general population.
Los Angeles has 3.4 million people, so that works out to about 900 to 3600.
When you add up chagas, resistant TB, MRSA, pork parasite brain worms in food supplies to Mexican immigrants illegal and legal (responsible for a large number of the seizures cases showing up in SoCal ERs), and maybe 'Morgellons', Southern California is due to become a disease hell I figure. Very worrisome.
Thanks for your published work.
Bert
www.latimes.com/news/local/la-me-chagas15mar15,0,5645224.story?track= mostviewed-storylevel
Parasite Is a Growing Concern For Health Care Professionals
One in 3,800 donors in the L.A. area tested positive for Chagas, a deadly disease that is mainly found in Latin America.
By Rong-Gong Lin II Times Staff Writer
March 15, 2007
A little-known but potentially deadly parasite from Latin America has become one of the latest threats to the blood and organ supplies in the United States, especially in Los Angeles, where many donors have traveled to affected countries, health officials say.
Last year, two heart transplant patients at different Los Angeles hospitals contracted the parasitic disease, called Chagas, causing health authorities to issue a national bulletin. Within months, both patients subsequently died, although not directly from Chagas, according to the U.S. Centers for Disease Control and Prevention.
The parasite, which is generally passed to humans from a blood-sucking insect that looks like a striped cockroach, can feed over years on tissues of the heart and gastrointestinal tract. After decades, tissues can be eroded so much that the organs fail.
Insect transmission of the parasite in the United States is rare, but public health and blood bank officials have been concerned about its increasing prevalence in the blood supply.
In 1996, using an experimental test, the American Red Cross found that one in 9,850 blood donors in the L.A. area tested positive for the parasite, Trypanosoma cruzi. Two years later, it was one in every 5,400. By 2006, a more refined test detected the parasite in one in 3,800 donors. About 10% to 30% of infected people develop symptoms of chronic disease, experts say.
By contrast, HIV, which blood banks screen for, shows up in one of every 30,000 donors, said Susan Stramer, executive scientific officer for the Red Cross.
If caught early, strong anti-protozoal drugs such as nifurtimox can bring the parasite to undetectable levels or, in some cases, eliminate it entirely.
If the parasite is given the chance to multiply over years or decades, however, those infected may have to be treated with heart-regulating drugs or get a pacemaker or heart transplant.
The U.S. Food and Drug Administration approved a test suitable for widespread screening in December. Blood banks have now begun systematically checking their supplies for the Chagas parasite.
By late January, the American Red Cross and Phoenix-based Blood Systems, which collect about 65% of the U.S. blood supply, had started screening blood for T. cruzi. Other banks, including the Blood Bank of San Bernardino and Riverside Counties, have no immediate plans for screening but are monitoring test results from banks that are using the test. In late February, the CDC reported that the "FDA is expected to recommend implementation of the test by all blood-collection establishments."
No organ donors in the United States are now being screened for the parasite, although the organ procurement agency that covers much of Southern California plans to begin testing some donors in mid-April. At first, the screening will be focused on people who have lived in or traveled to rural parts of Latin America, said Thomas Mone, chief executive of the agency, OneLegacy.
In Latin America, about 10 million to 12 million people are believed to be infected with the Chagas parasite. As many as 1 million of them are expected to die from the disease unless there are advances in treatment, according to Dr. James Maguire, a University of Maryland expert on the disease.
"Chagas is very, very prevalent in South and Central America," said Marek Nowicki, a USC blood-disease expert who studied the effect of Chagas on the Southern California organ supply with the National Institute of Transplantation.
"The number of [immigrant] Latinos in Southern California, Texas and other parts of the United States are growing, but especially in L.A., a large proportion of organ donors are Latino," Nowicki said. "They're basically bringing with them the disease prevalence in the area they used to live."
The problem is not limited to immigrants. Tourists, too, can be carriers. The heart transplant cases in Los Angeles last year illustrate the problem.
One donor was a native of El Salvador living in Los Angeles, and the other was born in the U.S. but had traveled to Guadalajara, Mexico, where T. cruzi is endemic.
Richard Edward Russo, then 73, received the heart from the Salvadoran native. The Burbank retiree appeared to be recovering nicely last year when, several weeks after his transplant at St. Vincent Medical Center in Los Angeles, he developed a fever and a rash. He complained of being tired and couldn't eat or walk.
About the same time, a 64-year-old man developed similar symptoms after receiving a transplant at UCLA Medical Center. He had received the heart from the American tourist.
At both hospitals, doctors submitted the patients to a battery of tests, concluding separately that they had Chagas.
The CDC sent anti-parasitic medication out from Atlanta. The drug reduced the parasite in the blood of both men to undetectable levels. But Russo never got better, his wife, Carolyn, said. He suffered from other hospital-acquired infections and had pneumonia at least twice.
"It just went downhill," she said. Russo died in June 2006.
As a result of the cases, the CDC last summer warned doctors that the prevalence of infection might be higher than previously thought, especially in areas like Los Angeles County.
Chagas is a clear reminder that "diseases don't have geographic borders anymore," said Dr. Suman Radhakrishna, an infectious diseases expert in Los Angeles who helped treat Russo. Doctors need to be "cognizant that diseases happening elsewhere in the world can happen in our backyard too."
Another disease, cysticercosis, caused by tapeworm larvae, is believed to cause as many as 10% of the seizures reported to large urban emergency rooms in California and New Mexico. Dr. Ashok Jain, a USC emergency room doctor, said the figure may be as high as 20% at Los Angeles County USC Medical Center.
It is spread through ingestion, not the blood or organ supply.
"When I was in Cook County in Chicago, I didn't even know it existed," said Jain, an associate professor of clinical emergency medicine at USC. "Then I came to L.A. County . and oh, God, there were so many cases."
Diseases like Chagas and cysticercosis have emerged as an issue for some opponents of illegal immigration, who argue that exotic diseases are often spread by illegal immigrants.
"Curbing illegal entry will diminish the problem of exposure to such diseases because legal immigrants are medically screened to protect the U.S. public," said Jack Martin, special projects director for the Federation for American Immigration Reform, an immigration control group..
Public health officials say the migration of diseases has always been an issue - and is especially so today, in an increasingly mobile world with a global economy. Many urge caution, not alarm.
"I don't want people to overreact, but I don't want people to ignore it," said Victor Tsang, chief of the immunochemistry lab at the CDC's Division of Parasitic Diseases. "The more we pay attention to it, the better off we are."
ron.lin@latimes.com
SoCal Headed To 'Hell'
From Patricia Doyle, PhD
3-16-7
Hello Bert,
Thank you for the article below. Given the fact that illegals from Chagas infected regions are flooding into the US every day, I think that we are going to see a full scale public health crisis in many areas of the US within 7-10 years.
Not only will public health officials become overwhelmed but hospitals will be forced share in this nightmare. I do not see how hospitals and the taxpayers are going to pay the bills of a Chagas-infected population. South and Central America are experiencing this very health crisis now.
Illegals are flocking into the US as 'workers.' There comes a time when a Chagas-infected person becomes unable to work. They then become in need of expensive, permanent medical care. The George Bush 'administration' is so shallow that it hasn't even begun to calculate the price of this 'CHEAP'(?) labor. Those who go onto the chronic stage of Chagas and the heart or colon problems will be unable to work and in need of assistance.
The local US kissing bug species have now demonstrated their ability to carry and vector the T. Cruzi parasite. These triatoma bugs have colonized homes and spread the parasite to local small animal populations and, as we saw in Louisiana, infected a 74 year old victim in her own home in New Orleans. Dogs, armidillos and other small animals serve as reservoir for the disease. This fact should have "served notice" that Chagas is capable of local spreading in the US. Triatoma bugs can be found in southern to mid latitudes in the US. These bugs can be found as far north as Maryland. There have been organ recipients who contracted Chagas from transplants and cases of simple blood transfusion transmission. Health authorities are not screening blood for Chagas.
Public health law would allow the government of the US to close down the border and stop anyone from entering the US from Chagas-infected regions. It is obvious that the US government is more concerned about 'cheap' labor for corporations and business entities than concern for the public health of its citizens. Furthermore, US the taxpayers will, as usual, receive the bill for medical care of Chagas infected, and the cost for Public health trying to deal with a crisis situation in the near future, let's say 2012. And what a bill that's going to be.
I just don't understand why, when we have a chance to stop the Chagas spread in the US, WHY are we not closing the borders? Deporting anyone who is infected with Chagas? This is a matter of the most basic common sense public health. This could just be the next pandemic and we have the power to stop it before it really gets rolling.
Once we allow the genie that is Chagas out of the bottle, there is NO stopping it. The CDC is misleading the public by calling Chagas a disease of poverty and poor living conditions. That's a lie. People from all walks of life and socioeconomic groups throughout Mexico, Central and South America have contracted Chagas. By telling Americans that the disease is one of poverty we are being lulled into believing we are immune to Chagas. Well, kissing bugs can colonize any home.
In Texas, triatoma bugs were found living under patio blocks. 24 of 31 triatomas were found positive for T. Cruzi. We have the vector, we have infected small animals and the vector had colonized homes within the US. This tells me we have a problem; we have conditions locally that favor Chagas spread within the US. Why are we allowing an influx of Chagas-infected people to continue to flood into the US, and do so ILLEGALLY?
2008 Presidential election is not far away. We need to DEMAND that prospective candidates take a stand on illegal immigration. If the current candidates won't take a stand than we need to find an anti-illegal immigration candidate who will.
Patricia
FYI
In the small community of San Benito, Texas (Figure 1), after three pet dogs died from Chagas cardiomyopathy, personnel from the Texas Department of Health, the Cameron County Health Department, Environmental Health Division, and the Centers for Disease Control and Prevention (CDC) inspected the owner's home, garage, and grounds for potential triatomine insect vectors (Figure 2). Blood was drawn from four dogs and two persons residing on the property and tested for antibodies to T. cruzi. A second site approximately 2 miles away was also inspected and blood drawn from three dogs, one of which had been diagnosed as positive for T. cruzi by the original veterinarian. A follow-up serologic survey was conducted to determine the percentage of the stray dogs in Cameron County that would test positive for Chagas disease antibodies. Once a week, samples from stray dogs were shipped to CDC for testing. Each sample was issued an identification number; and information on the animal's location, sex, age, health condition, and size was recorded. Serum specimens were tested for anti-T. cruzi antibodies by indirect immunofluorescence (IIF) (6,7).
Ecologic niches and potential geographic distributions were modeled by using the Genetic Algorithm for Rule-set Prediction (GARP) (8-10). In general, the procedure focuses on modeling ecologic niches, the conjunction of ecologic conditions within which a species is able to maintain populations without immigration. Specifically, GARP relates ecologic characteristics of known occurrence points to those of points randomly sampled from the rest of the study region, seeking to develop a series of decision rules that best summarizes those factors associated with the species' presence. Recently, this method has been used to study the distribution of species complex members and vector-reservoir relationships with respect to Chagas disease (11,12).
Inspection of the residence where the three dogs lived indicated a substantial infestation with the triatomine species T. gerstaeckeri (Figure 3). Triatomines were collected under cement slabs of a backyard patio adjacent to the house and from a garage located approximately 75 feet from the home (Figure 2). Of 31 live triatomines collected, including adults of both sexes and immature stages (i.e., two fifth-instar nymphs), 24 contained T. cruzi-like parasites in their hindgut (Figure 4). Cultures were established from triatomine urine collected from insects that were fed in the laboratory and placed in 1.5-mL microcentrifuge tubes. Approximately 50 µL of clear urine was injected into Novy, Nicolle, & MacNeal culture medium (13). The cultures were positive for parasites confirmed to be T. cruzi, on the basis of morphologic criteria. Inspection of the second residence failed to indicate a bug infestation; however, the pet owner recalled frequently observing both rats (Rattus spp.) and opossums (Didelphis virginiana) on the premises. At the first site, three of the four dogs tested positive for T. cruzi, with titers ranging from 1:128 to 1:256. Neither of the two persons had positive antibody titers against T. cruzi. At the second site, only the previously diagnosed dog tested positive, with a titer of 1:256. The other two dogs tested negative, as did the pet owner. Serum samples from stray dogs from Cameron County, Texas, were tested for antiT. cruzi antibodies. Of 375 dogs tested, 28 (7.5%) were positive by IIF, with titers ranging from 1:32 to 1:512. The sensitivity of this test in humans is 98.8% (pers. comm., Patricia P. Wilkins, Division of Parasitic Diseases, CDC). Because of the low specificity of serologic tests for distinguishing T. cruzi from Leishmania spp., all positive samples were tested for antibodies to L. donovani. A low level of cross-reactivity was observed in 17 of the 28 samples. In each case, however, the titer was 12 dilutions less than the titer to T. cruzi, indicating a primary response to T. cruzi rather than to Leishmania spp. Ecologic niche models for T. gerstaeckeri were developed by using GARP, based on published and unpublished collection records from Mexico and the southwestern United States. The model predicted a distribution for this species that extends from central Mexico, through central Texas, the Texas panhandle, into northern Texas and southeastern New Mexico (Figure 5).
Conclusions
Triatoma gerstaeckeri is considered a sylvatic species, most frequently associated with pack rat (Neotoma spp.) burrows (4). Although individual triatomine insects occasionally invade domestic dwellings throughout the southwestern United States and Mexico (4,5,14), this species has not been reported to colonize these habitats. In this investigation, colonization appears to have occurred, based on the observation of large numbers of bugs, including ones in immature stages. In the Chagas diseaseendemic regions of South and Central America, the primary risk for insect transmission to humans is related to the efficiency with which local vector species can invade and colonize homes, resulting in a domestic transmission cycle for what is otherwise exclusively a zoonotic disease in the southern United States. In disease-endemic countries, higher house infestation rates generally result in a higher risk of transmission. At the first site in south Texas, six dogs either died or tested positive for T. cruzi, and 24 of 31 bugs contained hindgut trypanosomes. These observations demonstrate the existence of a domestic transmission cycle for an insect species that is typically considered a zoonotic vector. Whether this observation represents an isolated case or actually occurs more frequently but remains unrecognized, indicating an emerging public health problem, remains to be determined. The serologic results in stray dogs are very similar to those reported in previous studies from the region, suggesting that the disease is stably maintained in this reservoir host (15,16). The distributional predictions based on GARP models indicate a potentially broad distribution for this species and suggest additional areas of risk beyond those previously reported (14), should this problem become of greater public health concern.
Dr. Beard is chief of the Vector Genetics Section in the Division of Parasitic Diseases, Centers for Disease Control and Prevention. His research focuses on the molecular biology of insect disease vectors and the molecular epidemiology of Pneumocystis pneumonia in HIV-infected persons.
Patricia A. Doyle DVM, PhD Bus
Admin, Tropical Agricultural Economics
Univ of West Indies
Please visit my "Emerging Diseases" message board at: www.emergingdisease.org/phpbb/index.php Also my new website: drpdoyle.tripod.com/ Zhan le Devlesa tai sastimasa Go with God and in Good Health
From: Bert To:
dr_p_doyle@hotmail.com>
Subject: article for you of possible interest from LA Times
Date: Fri, 16 Mar 2007
Hi. I appreciate all the material from you I see on Rense.
I'm sending this article from the Los Angeles Times in case you did not come across it elsewhere.
The Chagas-infected numbers are huge if you consider 1 in 3800 donors means perhaps 2 to 4x that in general population.
Los Angeles has 3.4 million people, so that works out to about 900 to 3600.
When you add up chagas, resistant TB, MRSA, pork parasite brain worms in food supplies to Mexican immigrants illegal and legal (responsible for a large number of the seizures cases showing up in SoCal ERs), and maybe 'Morgellons', Southern California is due to become a disease hell I figure. Very worrisome.
Thanks for your published work.
Bert
www.latimes.com/news/local/la-me-chagas15mar15,0,5645224.story?track= mostviewed-storylevel
Parasite Is a Growing Concern For Health Care Professionals
One in 3,800 donors in the L.A. area tested positive for Chagas, a deadly disease that is mainly found in Latin America.
By Rong-Gong Lin II Times Staff Writer
March 15, 2007
A little-known but potentially deadly parasite from Latin America has become one of the latest threats to the blood and organ supplies in the United States, especially in Los Angeles, where many donors have traveled to affected countries, health officials say.
Last year, two heart transplant patients at different Los Angeles hospitals contracted the parasitic disease, called Chagas, causing health authorities to issue a national bulletin. Within months, both patients subsequently died, although not directly from Chagas, according to the U.S. Centers for Disease Control and Prevention.
The parasite, which is generally passed to humans from a blood-sucking insect that looks like a striped cockroach, can feed over years on tissues of the heart and gastrointestinal tract. After decades, tissues can be eroded so much that the organs fail.
Insect transmission of the parasite in the United States is rare, but public health and blood bank officials have been concerned about its increasing prevalence in the blood supply.
In 1996, using an experimental test, the American Red Cross found that one in 9,850 blood donors in the L.A. area tested positive for the parasite, Trypanosoma cruzi. Two years later, it was one in every 5,400. By 2006, a more refined test detected the parasite in one in 3,800 donors. About 10% to 30% of infected people develop symptoms of chronic disease, experts say.
By contrast, HIV, which blood banks screen for, shows up in one of every 30,000 donors, said Susan Stramer, executive scientific officer for the Red Cross.
If caught early, strong anti-protozoal drugs such as nifurtimox can bring the parasite to undetectable levels or, in some cases, eliminate it entirely.
If the parasite is given the chance to multiply over years or decades, however, those infected may have to be treated with heart-regulating drugs or get a pacemaker or heart transplant.
The U.S. Food and Drug Administration approved a test suitable for widespread screening in December. Blood banks have now begun systematically checking their supplies for the Chagas parasite.
By late January, the American Red Cross and Phoenix-based Blood Systems, which collect about 65% of the U.S. blood supply, had started screening blood for T. cruzi. Other banks, including the Blood Bank of San Bernardino and Riverside Counties, have no immediate plans for screening but are monitoring test results from banks that are using the test. In late February, the CDC reported that the "FDA is expected to recommend implementation of the test by all blood-collection establishments."
No organ donors in the United States are now being screened for the parasite, although the organ procurement agency that covers much of Southern California plans to begin testing some donors in mid-April. At first, the screening will be focused on people who have lived in or traveled to rural parts of Latin America, said Thomas Mone, chief executive of the agency, OneLegacy.
In Latin America, about 10 million to 12 million people are believed to be infected with the Chagas parasite. As many as 1 million of them are expected to die from the disease unless there are advances in treatment, according to Dr. James Maguire, a University of Maryland expert on the disease.
"Chagas is very, very prevalent in South and Central America," said Marek Nowicki, a USC blood-disease expert who studied the effect of Chagas on the Southern California organ supply with the National Institute of Transplantation.
"The number of [immigrant] Latinos in Southern California, Texas and other parts of the United States are growing, but especially in L.A., a large proportion of organ donors are Latino," Nowicki said. "They're basically bringing with them the disease prevalence in the area they used to live."
The problem is not limited to immigrants. Tourists, too, can be carriers. The heart transplant cases in Los Angeles last year illustrate the problem.
One donor was a native of El Salvador living in Los Angeles, and the other was born in the U.S. but had traveled to Guadalajara, Mexico, where T. cruzi is endemic.
Richard Edward Russo, then 73, received the heart from the Salvadoran native. The Burbank retiree appeared to be recovering nicely last year when, several weeks after his transplant at St. Vincent Medical Center in Los Angeles, he developed a fever and a rash. He complained of being tired and couldn't eat or walk.
About the same time, a 64-year-old man developed similar symptoms after receiving a transplant at UCLA Medical Center. He had received the heart from the American tourist.
At both hospitals, doctors submitted the patients to a battery of tests, concluding separately that they had Chagas.
The CDC sent anti-parasitic medication out from Atlanta. The drug reduced the parasite in the blood of both men to undetectable levels. But Russo never got better, his wife, Carolyn, said. He suffered from other hospital-acquired infections and had pneumonia at least twice.
"It just went downhill," she said. Russo died in June 2006.
As a result of the cases, the CDC last summer warned doctors that the prevalence of infection might be higher than previously thought, especially in areas like Los Angeles County.
Chagas is a clear reminder that "diseases don't have geographic borders anymore," said Dr. Suman Radhakrishna, an infectious diseases expert in Los Angeles who helped treat Russo. Doctors need to be "cognizant that diseases happening elsewhere in the world can happen in our backyard too."
Another disease, cysticercosis, caused by tapeworm larvae, is believed to cause as many as 10% of the seizures reported to large urban emergency rooms in California and New Mexico. Dr. Ashok Jain, a USC emergency room doctor, said the figure may be as high as 20% at Los Angeles County USC Medical Center.
It is spread through ingestion, not the blood or organ supply.
"When I was in Cook County in Chicago, I didn't even know it existed," said Jain, an associate professor of clinical emergency medicine at USC. "Then I came to L.A. County . and oh, God, there were so many cases."
Diseases like Chagas and cysticercosis have emerged as an issue for some opponents of illegal immigration, who argue that exotic diseases are often spread by illegal immigrants.
"Curbing illegal entry will diminish the problem of exposure to such diseases because legal immigrants are medically screened to protect the U.S. public," said Jack Martin, special projects director for the Federation for American Immigration Reform, an immigration control group..
Public health officials say the migration of diseases has always been an issue - and is especially so today, in an increasingly mobile world with a global economy. Many urge caution, not alarm.
"I don't want people to overreact, but I don't want people to ignore it," said Victor Tsang, chief of the immunochemistry lab at the CDC's Division of Parasitic Diseases. "The more we pay attention to it, the better off we are."
ron.lin@latimes.com