Advice and guidance on the health needs of migrant patients for healthcare practitioners.
Chronic cases of Chagas disease are increasingly being reported in Europe in migrants from Latin America. So far, it has only rarely been reported in the UK, but may well be under-recognised.
Consider the possibility of Chagas disease in at risk migrants with cardiac and gastrointestinal symptoms, because patients may present with these symptoms in the chronic phase.
Refer the patient, where the disease is suspected, to:
Offer serological testing for Chagas disease to at risk pregnant women, and refer any positives to a specialist centre.
Follow up infants of seropositive mothers to detect and treat any cases of vertical transmission.
Be aware of the regulations around blood donation for migrants from countries which are endemic for Chagas disease.
Chagas disease (American trypanosomiasis) is a zoonosis caused by the flagellated protozoan parasite Trypanosoma cruzi, which:
- affects 6 to 7 million people worldwide
- is endemic in large parts of Central and South America, especially in poor rural areas
- kills more people than any other parasitic disease in Latin America
- has only rarely been reported in the UK, and all cases identified have been migrants from Latin America
As a result of population movements, cases of Chagas disease are increasingly being recognized in European countries, mainly those with strong historical links to countries in South and Central America.
It is likely that this disease is currently under-recognized in the UK, based on the:
- migration data
- known prevalence of the disease in endemic countries
Prevalence of Chagas disease by country
|Country||Prevalence per 100 population|
|French Guyana, Guyana & Suriname||0.838|
Source: WHO. Chagas disease in Latin America: an epidemiological update based on 2010 estimates. Weekly epidemiological record 2015: volume 90, pages 33-44.
Central and South America
Chagas disease is primarily transmitted to people by the infected faeces of a blood-sucking triatomine bug, through:
- the site of the insect bite
- another skin breach
- mucous membranes, including:
- oral or digestive mucosa
- contaminated food (only occasionally)
The triatomine bug thrives under poor housing conditions (for example, mud walls, thatched roofs).
The triatomine bug does not occur in the UK, so ongoing transmission from infected people by this route is not an issue. However, transmission in the UK is possible through:
- blood transfusion
- pregnancy and delivery
- organ transplantation
- laboratory accident (less frequently)
Find out about prevention and control of Chagas disease.
The acute phase of infection commonly lasts around 2 months immediately after infection. Most cases have few or no symptoms, but there may be:
- a skin chancre (chagoma)
- unilateral purplish orbital oedema (Romaña’s sign) with local lymphadenopathy and fever over several weeks
More general symptoms include:
- oedema in inferior limbs or face
- abdominal pain
- painful nodules
- generalized oedema
- multiple lymphadenopathy
- myocarditis (chest pain, heart failure)
- more rarely meningoencephalitis (seizures, paralysis)
The chronic phase is associated with no symptoms in the majority of patients, but 20 to 30% will go on to develop cardiac and/or digestive manifestations over the next decades.
Cardiac sequelae include:
- conduction disorders
- heart failure
- cardiac aneurysm
- secondary thromboembolism
Digestive lesions include:
Consider the possibility of Chagas disease in migrants from endemic South and Central American countries.
If the disease is suspected, request serology for Chagas disease (clotted blood sample).
If positive, and dependent upon the individual clinical presentation, refer the patient for:
- further management to the local cardiology or gastroenterology department
- definitive serological confirmation of the diagnosis, and consideration of anti-parasitic treatment, to one of several expert parasitology centres in the UK:
- the Hospital for Tropical Diseases at University College Hospital
- the Liverpool School of Tropical Medicine and the associated Tropical and Infectious Disease Unit in the Royal Liverpool University Hospital provide advice on prevention, diagnosis and management of tropical infections.
Two treatments are available for Chagas disease, both of which are used on a named patient basis by specialist parasitology centres, and available on request from WHO:
Treatment is generally considered to be more effective:
- for those in the acute or early chronic phase
- during reactivation if the patient becomes immunosuppressed
It is also used in cases of congenital infection.
The treatment schedule is long and is associated with frequent side effects. Once the characteristic pathology is established (eg dilated cardiomyopathy, mega-oesophagus), be aware that:
- antiparasitic treatment will not reverse it
- symptomatic treatment is the mainstay of management
Prevention and control
In the UK, the 2 main transmission risks are:
Transfusion or transplantation
Pre-donation (blood or transplant) screening has been in place in the UK since 1999.
In the UK, a potential donor must not donate if:
they were born in South America or Central America (including southern Mexico, but not the Caribbean Islands)
their mother was born in South America or Central America (including southern Mexico, but not the Caribbean Islands)
they had a blood transfusion in South America or Central America (including southern Mexico, but not the Caribbean Islands)
they lived and/or worked in rural subsistence farming communities in these countries for a continuous period of 4 weeks or more
However, a donor may donate, and the donation is used, if both of the following conditions apply:
- at least 6 months have elapsed since the last exposure
- a validated test for T.cruzi antibody is negative
There is currently no routine antenatal screening programme for Chagas in the UK.
Offer serological testing to pregnant women from the at-risk groups.
The World Health Organization (WHO) has further information on Chagas disease.
The National Travel Health Network and Centre (NaTHNaC) provides country specific travel advice.