Dr Antonia Margarita Lavenia: Physician of the Chagas Disease Control Programme in Tucumán. Associate Professor in charge of the Chair of Parasitology of the School of Medicine of the National University of Tucumán (UNT).
Main transmission route
Chagas disease is an important cause of morbidity and mortality in the Americas; 6 to 8 million people are estimated to be infected at present, with an annual incidence of 200,000 cases in the 21 endemic countries.
Vertical transmission continues to be the main transmission route in Tucumán, an Argentine province that was certified as Free of Vectorial Transmission in 2015.
Strategies to diagnose and treat children of positive mothers:
- First, training the health team and raising their awareness. The commitment of all the members of the health team is a key factor to make this neglected disease visible.
- National Law 26281, article 4, establishes that every pregnant women must be screened for Chagas disease.
- Doing the test before the first year of life of the child born to a reactive mother, with Direct Parasitological studies (Micro strout or micromethod) and PCR at birth, at one month of age, and Serology at 10 months of age.
- Performing serological tests to the rest of the children of the reactive mother.
- Treating every positive child and providing treatment to that reactive woman, of childbearing age, during the puerperium, preferably six months after delivery.
In Tucumán, at present, prevalence of connatal Chagas disease decreased from 6% to less than 3.5%.
Training of primary health care teams
We start the workshops by asking whether the team of medical doctors, biochemists or health agents suspect that a child or an adult may be infected with Trypanosoma cruzi. In addition, we ask whether they can treat that suspected patient and who would treat that patient. This is because the patient must be treated at the Primary Care level; patients should not need to seek care from a specialist in Infectious diseases at a Third-level Hospital.
Information, education and communication to the community
A community that is not aware of this, if we do not make it visible, will not be ready to control it. Therefore, the community is informed and educated and receives communication about Chagas disease.
Indication of etiological treatment of infection with T. Cruzi
Indications have diverse strength of recommendation and level of evidence to prescribe any of the two currently available drugs, Benznidazole and Nifurtimox.
Criteria for prescription:
- Patients in the acute phase or reactivation.
- Children and patients under 19 years of age in chronic phase.
- Adults in chronic phase, up to 50 years of age, provided that they do not have organ damage.
- Patients with surgery or laboratory accidents.
- Organ transplant recipients or donors.
Trypanocidal drugs
We still use them; we are hopeful that the ongoing studies on new drugs to shorten treatment duration will be successful.
We know the contraindications: they cannot be administered to pregnant women, patients with renal or hepatic failure, or patients with sensitivity to the drugs; alcohol consumption is forbidden. Among the adverse effects of Benznidazole are skin rashes, headaches, peripheral neuropathies, which are reversible upon withdrawal of the drug. The adverse effects of Nifurtimox are more related to gastrointestinal symptoms.
In turn, when the Ministry of Health of Argentina published the Guidelines for the Treatment of patients infected with Trypanosoma cruzi in 2012, we noticed how patients with chronic Chagas disease started to spontaneously demand trypanocidal treatment, since the disease can be treated and cured.
Finally, I would like to stress that a child that is not treated today may be an adult with Chagas disease in the future.