A decade of vector control activities: Progress and limitations of Chagas disease prevention in a region of Guatemala with persistent Triatoma dimidiata infestation

Abstract

IntroductionChagas disease, a neglected tropical disease that affects millions of Latin Americans, has been effectively controlled in Guatemala after multiple rounds of indoor residual insecticide spraying (IRS). However, a few foci remain with persistent Triatoma dimidiata infestation. One such area is the municipality of Comapa, Department of Jutiapa, in the southeastern region of Guatemala, where control interventions appear less effective. We carried out three cross sectional entomological and serological surveys in Comapa to evaluate a decade of vector control activities. Baseline serological (1999) and entomological (2001–2) surveys were followed by three rounds of insecticide applications (2003–2005) and intermittent focal spraying of infested houses, until approximately 2012. Household inspections to determine entomological indices and construction materials were conducted in 2001, 2007 and 2011. Seroprevalence surveys were conducted in school-age children in 1999, 2007 and 2015, and in women of child bearing age (15–44 years) only in 2015. After multiple rounds of indoor residual sprayings (IRS), the infestation index decreased significantly from 39% (2001–2) to 27% (2011). Household construction materials alone predicted <10% of infested houses. Chagas seroprevalence in Comapa declined in school-aged children by 10–fold, from 10% (1999) to 1% (2015). However, seroprevalence in women of child bearing age remains >10%.ConclusionAfter a decade of vector control activities in Comapa, there is evidence of significantly reduced transmission. However, the continued risk for vector-borne and congenital transmission pose a threat to the 2022 Chagas disease elimination goal. Systematic integrated vector control and improved Chagas disease screening and treatment programs for congenital and vector-borne disease are needed to reach the elimination goal in regions with persistent vector infestation.

Biopharmaceutical Characteristics of Nifurtimox Tablets for Age‐ and Body Weight‐Adjusted Dosing in Patients With Chagas Disease

“…The most common TEAEs observed during the studies were gastrointestinal disorders (vomiting, nausea, and abdominal pain) and headache, which are known side effects of nifurtimox. 4 All nifurtimoxrelated TEAEs were mild or moderate in intensity and resolved, mostly within a day, as has previously been reported with the drug. 15,25,26 Although it is difficult to draw conclusions about safety and tolerability from relatively small, single-dose studies, the frequency and type of TEAEs were broadly the same across all intervention groups, and no severe or serious events were reported.…”

“…3 Currently, vector transmission is partially controlled, and most of the new cases occur in urban areas through congenital transmission. 4 A study was conducted in 2008 in 12 776 children aged 1-5 years in contiguous rural areas in which uninterrupted vector-control measures had been in place since 1999. The study determined that the seroprevalence rate of Chagas disease in this pediatric population was 0.24% and was attributable to vertical transmission of the parasite.…”

Cruzipain and Its Physiological Inhibitor, Chagasin, as a DNA-Based Therapeutic Vaccine Against Trypanosoma cruzi

“…Despite vector control programs effectively reducing the level of infestation, when they are not sustained over time, reinfection of treated households reaches levels like the initial one ( 6 ). This was mainly seen in rural areas, when constructions are poor or in peridomestic areas with domestic animals ( 7 ). Several concerns remain a challenge, namely, disease globalization due to migration ( 1 , 8 ); the existence of alternative routes of transmission, such as mother-to-child or oral transmission through contaminated food or beverages ( 9 ); and the high variability in drug sensitivity across multiple strains of T. cruzi ( 10 ).…”

Population Pharmacokinetics of Nifurtimox in Adult and Pediatric Patients With Chagas Disease

“…2 Chagas disease may also be spread through blood transfusion and organ transplantation, ingestion of food contaminated with parasites, and from a mother to her fetus. 3,4 Thus, the patient population that is affected by this disease ranges from newborn pediatric patients to adults.…”

“…T cruzi is commonly transmitted to humans and other mammals by insect vectors, the bloodsucking so‐called “kissing bugs” of the subfamily Triatominae (family Reduviidae) 2 . Chagas disease may also be spread through blood transfusion and organ transplantation, ingestion of food contaminated with parasites, and from a mother to her fetus 3,4 . Thus, the patient population that is affected by this disease ranges from newborn pediatric patients to adults.…”