Please welcome another guest post by Charles Ebikeme. –Beth
Chagas is a more dangerous and much more pervasive disease than we give it credit for. A tropical disease that is really no longer quarantined to the tropics, Chagas has been known to turn up in unlikely places — and those unlikely places are becoming more and more important.
Chagas is also known as American trypanosomiasis, and is found mainly in Latin America, where it is mostly transmitted to humans by the faeces of the triatomine “kissing bug”. About 7 to 8 million people are estimated to be infected with Chagas worldwide.
Recently, researchers at the Center for Clinical Epidemiology and Biostatistics demonstrated that bed bugs can transmit Trypanosoma cruzi, the infectious parasitic agent that causes Chagas disease. They found that bed bugs, a not too unrelated cousin of the kissing bug, can transmit the parasite in the same way by which humans are usually infected. Both bed and kissing bugs only feed on blood, and both hide in household cracks and crevices waiting for nightfall and the opportunity to feed on sleeping hosts.
The discovery that bed bugs can transmit Chagas is not the first time the disease has turned up via an unlikely route.
In March of 2001, a 37 year old woman went into surgery in the US to have a kidney and pancreas transplant from a donor that had already passed away. She would die six months later, on the first week of October from Chagas. The parasite had been contracted from the organ transplant.
Outside of the bite and faeces of the kissing bug the parasite can be transmitted in more (extra)ordinary ways — from mother to child, and through contaminated blood or organ donations. In the US blood supplies have only routinely been screened for Chagas since 2007.
In southern states of the US, the kissing bug also roams, and recent research has shown that some cases of Chagas disease are originating domestically. There’s a need to look more carefully for local infections in Texas and elsewhere in the South. And given the pathology of the disease, many people who are infected may not know they carry the parasite.
In recent years, it has become more apparent that Chagas is now not just confined to the Americas. It hasn’t been for some time. Chagas has now spread to other continents, and Europe is its most recent port of call.
The first reported case of Chagas in Europe was in 1981. Ever since then, sporadic cases have been detected in different European countries. Since the turn of the millennium the numbers of reported cases have only increased, particularly in Spain, Italy, and Switzerland. In Europe, the currently estimated number of people with Chagas is somewhere between 68,000 and 122,000, yet by 2009 only 4,290 had been diagnosed.
Chagas is a real threat. The global cost of the disease worldwide is thought to be at around 7.2 billion US dollars per year — an amount that is comparable to cervical cancer.
How prepared is Europe for Chagas?
Researchers, publishing in PLOS, sent out questionnaires on health policy for T. cruzi infection to about a dozen European countries. They wanted to gauge policy on the possibility of infection via blood transfusion, transplantation, and congenital transmissions. Some European countries are slowly beginning to acknowledge this growing public health problem, and some changes in health policies have been implemented.
Some, but not all, European countries have implemented national or regional measures to control transmission, but many countries still have no legislation about Chagas disease within their borders.
For risk of infection via blood transfusions seven European countries have either already implemented, or are in the process of, changing recommendations to enhance detection of cases of infection (France, Italy, Portugal, Spain, Sweden, Switzerland, and the United Kingdom).
No country in Europe has a specific health policy against the risk of infection by organ transplantation. Only in Italy, Spain, and the United Kingdom are donors at risk of the infection being screened.
Of all the three possible routes of extraordinary infection, it is the congenital route that is the least well developed in terms of health policy. This in the face of the fact that control of congenital transmission has been demonstrated to be one of the most cost-effective measures to control the disease, since newborns with acute disease can be cured easily if treatment and diagnosis is early.
The recommendation from authors is an evolving health policy to control Chagas disease transmission in Europe. Across Europe, the map of policies is a mixed one — some laws and directives concerning blood banks and transplant programmes are urgently needed to avoid and reduce the risk of transmission. The differences in regulations emanating from the European Commission are not always in line with the Council of Europe, which should be addressed to give some coherence. Where laws and regulations do exists, more effort needs to be made to evaluate their implementation and impact.
Charles Ebikeme is a science journalist with a PhD in parisitology who serves as a Science Officer with the International Social Science Council of UNESCO and writes frequently on global health, health policy, neglected tropical diseases and infectious diseases for The Huffington Post, The Guardian, Scientific American, and Think Africa Press. He is based in Paris. You can find him on Twitter @CEbikeme.