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The study of catastrophic costs incurred by people affected by tuberculosis (TB), conducted in Colombia during the COVID-19 pandemic, provided the opportunity to implement telephone surveys for data collection. This constitutes a methodological innovation regarding the standards established by the World Health Organization (WHO) which, for this type of study, usually rely on face-to-face surveys of patients attending health facilities. The study design, objectives, and methodology were adapted from the WHO publication Tuberculosis patient cost surveys: a handbook . A total of 1065 people affected by tuberculosis were selected as study participants and, by telephone, were administered a standard questionnaire adapted to the Colombian context. This allowed the collection of structured data on the direct and indirect costs faced by TB patients and their families. Greater than 80% completeness was achieved for all variables of interest, with an average survey duration of 40 minutes and a rejection rate of 8%. The described survey method to determine the baseline for further study of catastrophic costs in Colombia was novel because of its telephone-based format, which adheres to the information standards required to allow internationally comparable estimates. It is a useful means of generating standardized results in contexts in which the ability to conduct face-to-face surveys is limited., Competing Interests: Conflictos de intereses. Ninguno declarado por los autores.

Competing Interests: Conflict of interest statement: The authors declare that there is no conflict of interest.

The pork tapeworm, Taenia solium , is among the leading causes of preventable epilepsy in the world and is common in rural areas of developing countries where sanitation is limited and pigs have access to human feces. Prior studies in rural villages of Peru have observed clusters of T. solium cysticercosis among pigs that live near human tapeworm carriers. Such spatial analyses, however, have been limited by incomplete participation and substandard diagnostic tests. In this study, we evaluated the association between necropsy-confirmed cysticercosis in pigs and their distance to T. solium tapeworm carriers in six villages in northern Peru. A total of six (1.4%) tapeworm carriers were detected using copro-antigen enzyme-linked immunosorbent assay and seven of 10 (70%) pigs belonging to the tapeworm carriers were found with viable cyst infection on necropsy. This was significantly greater than the prevalence of viable cyst infection among pigs living < 500 m (11%) and > 500 m (0.5%) from a tapeworm carrier ( P < 0.001 for distance trend). Similar statistically significant prevalence gradients were observed after adjustment for possible confounders and for other pig-level outcomes including infection with > 10 viable cysts, degenerated cyst infection, and serological outcomes. This investigation confirms that porcine cysticercosis clusters strongly around tapeworm carriers in endemic rural regions of northern Peru and supports interventions that target these hotspots.

Objective: To identify 1) the main determinants of persistent Yersinia pestis circulation and the associated threat of plague at Hermelinda Market-a large farmers' market in the city of Trujillo, La Libertad, Peru-and the main actions taken against it, as perceived by local stakeholders; 2) the level of plague risk perception among local actors; and 3) recommended actions to solve the plague threat at the market ., Methods: A conceptual framework was developed combining a social determinants approach with a complex systems-thinking framework and a knowledge management perspective. A four-step qualitative protocol was carried out (literature review; stakeholder mapping; 37 semi-structured interviews; and coding/analysis). In the fourth step, the data collected in the semi-structured interviews were coded for eight social determinants of health (SDH) variables and analyzed with ATLAS.ti®, and an emerging category analysis was performed to identify risk perception levels ., Results: Based on analysis by SDH variable, the three main determinants of the plague threat at Hermelinda Market were: 1) local (Trujillo City) governance, 2) infrastructure and basic services, and 3) local culture. According to the same analysis, actions most frequently undertaken against plague involved 1) infrastructure and basic services, 2) social vigilance, and 3) communication. The emerging category analysis indicated local risk perception levels were low, with most of the data pointing to "unhygienic" ("naturalized") lifestyles and a general lack of awareness about the disease prior to plague-related health concerns at the market as the cause ., Conclusions: The results indicate that the persistent circulation of Yersinia pestis at Hermelinda Market is not simply a technical matter but more of a managerial and cultural problem. As local governance was found to be a main factor in the persistence of this public health threat, future efforts against it should focus on sustainable inter-sectoral planning and education. Actions taken exclusively by the health sector and the improvement of infrastructure and basic services alone will not be enough to reduce the threat of plague at the market ., Competing Interests: Conflicts of interest. None.

Background: Neurocysticercosis is a common helminthic infection of the central nervous system and an important cause of adult-onset epilepsy in endemic countries. However, few studies have examined associations between neurologic symptoms, serology and radiographic findings on a community-level., Methodology: We conducted a population-based study of resident's ≥2 years old in a highly endemic village in Peru (pop. 454). We applied a 14 -question neurologic screening tool and evaluated serum for antibodies against Taenia solium cysticercosis using enzyme-linked immunoelectrotransfer blot (LLGP-EITB). We invited all residents ≥18 years old to have non-contrast computerized tomography (CT) of the head., Principal Findings: Of the 385 residents who provided serum samples, 142 (36.9%) were seropositive. Of the 256 residents who underwent CT scan, 48 (18.8%) had brain calcifications consistent with NCC; 8/48 (17.0%) reported a history of headache and/or seizures. Exposure to T. solium is very common in this endemic community where 1 out of 5 residents had brain calcifications. However, the vast majority of people with calcifications were asymptomatic., Conclusion: This study reports a high prevalence of NCC infection in an endemic community in Peru and confirms that a large proportion of apparently asymptomatic residents have brain calcifications that could provoke seizures in the future., Competing Interests: The authors have declared that no competing interests exist.

Background: Taeniasis and cysticercosis are major causes of seizures and epilepsy. Infection by the causative parasite Taenia solium requires transmission between humans and pigs. The disease is considered to be eradicable, but data on attempts at regional elimination are lacking. We conducted a three-phase control program in Tumbes, Peru, to determine whether regional elimination would be feasible., Methods: We systematically tested and compared elimination strategies to show the feasibility of interrupting the transmission of T. solium infection in a region of highly endemic disease in Peru. In phase 1, we assessed the effectiveness and feasibility of six intervention strategies that involved screening of humans and pigs, antiparasitic treatment, prevention education, and pig replacement in 42 villages. In phase 2, we compared mass treatment with mass screening (each either with or without vaccination of pigs) in 17 villages. In phase 3, we implemented the final strategy of mass treatment of humans along with the mass treatment and vaccination of pigs in the entire rural region of Tumbes (107 villages comprising 81,170 people and 55,638 pigs). The effect of the intervention was measured after phases 2 and 3 with the use of detailed necropsy to detect pigs with live, nondegenerated cysts capable of causing new infection. The necropsy sampling was weighted in that we preferentially included more samples from seropositive pigs than from seronegative pigs., Results: Only two of the strategies implemented in phase 1 resulted in limited control over the transmission of T. solium infection, which highlighted the need to intensify the subsequent strategies. After the strategies in phase 2 were implemented, no cyst that was capable of further transmission of T. solium infection was found among 658 sampled pigs. One year later, without further intervention, 7 of 310 sampled pigs had live, nondegenerated cysts, but no infected pig was found in 11 of 17 villages, including all the villages in which mass antiparasitic treatment plus vaccination was implemented. After the final strategy was implemented in phase 3, a total of 3 of 342 pigs had live, nondegenerated cysts, but no infected pig was found in 105 of 107 villages., Conclusions: We showed that the transmission of T. solium infection was interrupted on a regional scale in a highly endemic region in Peru. (Funded by the Bill and Melinda Gates Foundation and others.).

Background: The prevalence of epilepsy added to inadequate treatment results in chronic morbidity and considerable mortality in poor populations. Neurocysticercosis (NCC), a helminthic disease of the central nervous system, is a leading cause of seizures and epilepsy in most of the world., Methods: Taking advantage of a cysticercosis elimination program, we performed two community-based cross-sectional studies between 2006 and 2007 in 58 rural communities (population 20,610) to assess the prevalence and characteristics of epilepsy and epileptic seizures in this endemic region. Serological and computed tomography (CT) data in individuals with epilepsy were compared to previous surveys in general population from the same region., Principal Findings: In two surveys, 17,450 individuals were evaluated. Lifetime prevalence of epilepsy was 17.25/1000, and prevalence of active epilepsy was 10.8/1000 inhabitants. The prevalence of epilepsy increased after age 25 years and dropped after age 45. Only 24% (45/188) of patients with active epilepsy were taking antiepileptic drugs, all at sub-therapeutic doses. Antibodies to cysticercosis were found in approximately 40% of individuals with epilepsy in both studies. In one survey only individuals presenting strong antibody reactions were significantly associated with having epilepsy (OR 5.74; p<0.001). In the second, the seroprevalence as well as the proportion presenting strong antibody reactions were both significantly higher in individuals with epilepsy (OR 2.2 and 4.33, respectively). Brain CT showed NCC-compatible images in 109/282 individuals with epilepsy (39%). All individuals with viable parasites on CT were seropositive., Conclusion: The prevalence of epilepsy in this cysticercosis endemic region is high and NCC is an important contributor to it.

It is unclear if the relationship of total serum IgE with asthma varies with degree of urbanisation. We hypothesised that the relationship of total serum IgE to asthma is more pronounced in an urban versus a rural environment. We enrolled 1441 children aged 13-15 years in a peri-urban shanty town in Lima, Peru (n=725) and 23 villages in rural Tumbes, Peru (n=716). We asked participants about asthma and allergy symptoms, environmental exposures and sociodemographics; and performed spirometry, and exhaled nitric oxide and allergy skin testing. We obtained blood for total serum IgE in 1143 (79%) participants. Geometric means for total serum IgE were higher in Lima versus Tumbes (262 versus 192 kU·L(-1); p<0.001). The odds of asthma increased by factors of 1.6 (95% CI 1.3-2.0) versus 1.4 (95% CI 0.9-2.1) per log unit increase in total serum IgE in Lima versus Tumbes, respectively. Atopy was an effect modifier of the relationship of total serum IgE on asthma. Among atopics and non-atopics, the odds of asthma increased by a factor of 2.0 (95% CI 1.5-2.7) and 1.0 (95% CI 0.7-1.4) per log unit increase in total serum IgE, respectively. Total serum IgE was associated with atopic asthma but not with non-atopic asthma. Urbanisation did not appear to be an effect modifier of this relationship.

Objectives: According to a large-scale international survey, Peru has one of the highest prevalences of asthma worldwide; however, data from this survey were limited to participants from urban Lima. The authors sought to characterise the epidemiology of asthma in Peru in two regions with disparate degrees of urbanisation. In this manuscript, the authors summarise the study design and implementation., Design: A cross-sectional study., Participants: Using census data of 13-15-year-old adolescents from two communities in Peru, the authors invited a random sample of participants in Lima (n=725) and all adolescents in Tumbes (n=716) to participate in our study., Primary and Secondary Outcome Measures: The authors asked participants to complete a questionnaire on asthma symptoms, environmental exposures and socio-demographics and to undergo spirometry before and after bronchodilator, skin allergy testing and exhaled nitric oxide testing. The authors obtained blood samples for haematocrit, total IgE levels, vitamin D levels and DNA in all participants and measured indoor particulate matter concentrations for 48 h in a random subset of 70-100 households at each site., Results: Of 1851 eligible participants, 1441 (78%) were enrolled and 1159 (80% of enrolled) completed all physical tests. 1283 (89%) performed spirometry according to standard guidelines, of which 86% of prebronchodilator tests and 92% of postbronchodilator tests were acceptable and reproducible. 92% of allergy skin tests had an adequate negative control. The authors collected blood from 1146 participants (79%) and saliva samples from 148 participants (9%). Overall amounts of DNA obtained from blood or saliva were 25.8 μg, with a 260/280 ratio of 1.86., Conclusions: This study will contribute to the characterisation of a variety of risk factors for asthma, including urbanisation, total IgE levels, vitamin D levels and candidate genes, in a resource-poor setting. The authors present data to support high quality of survey, allergic, spirometric and genetic data collected in our study.

Background: Neurocysticercosis is a leading cause of preventable epilepsy in the developing world. Sustainable community-based interventions are urgently needed to control transmission of the causative parasite, Taenia solium. We examined the geospatial relationship between live pigs with visible cysticercotic cysts on their tongues and humans with adult intestinal tapeworm infection (taeniasis) in a rural village in northern Peru. The objective was to determine whether tongue-positive pigs could indicate high-risk geographic foci for taeniasis to guide targeted screening efforts. This approach could offer significant benefit compared to mass intervention., Methods: We recorded geographic coordinates of all village houses, collected stool samples from all consenting villagers, and collected blood and examined tongues of all village pigs. Stool samples were processed by enzyme-linked immunosorbent assay (ELISA) for presence of Taenia sp. coproantigens indicative of active taeniasis; serum was processed by enzyme-linked immunoelectrotransfer blot for antibodies against T. solium cysticercosis (EITB LLGP) and T. solium taeniasis (EITB rES33)., Findings: Of 548 pigs, 256 (46.7%) were positive for antibodies against cysticercosis on EITB LLGP. Of 402 fecal samples, 6 (1.5%) were positive for the presence of Taenia sp. coproantigens. The proportion of coproantigen-positive individuals differed significantly between residents living within 100-meters of a tongue-positive pig (4/79, 5.1%) and residents living >100 meters from a tongue-positive pig (2/323, 0.6%) (p = 0.02). The prevalence of taeniasis was >8 times higher among residents living within 100 meters of a tongue-positive pig compared to residents living outside this range (adjusted PR 8.1, 95% CI 1.4-47.0)., Conclusions: Tongue-positive pigs in endemic communities can indicate geospatial foci in which the risk for taeniasis is increased. Targeted screening or presumptive treatment for taeniasis within these high-risk foci may be an effective and practical control intervention for rural endemic areas.

Neurocysticercosis, the infection of the human central nervous system by the larval stage of the cestode Taenia solium, is an important cause of epilepsy and other neurological manifestations in Peru and most developing countries. Since 1987, the Cysticercosis Working Group in Peru has performed a series of epidemiological studies which led to estimate the impact and to better understand the transmission of Taenia solium. This information was later applied to the design and execution of a control program in Tumbes, in the Northern Coast of Peru. This paper reviews the main epidemiological findings, as well as the conceptual framework of the elimination program and the tools used. Advances in the control of taeniasis/cysticercosis in our country open the road towards its elimination and potential eradication.

Background: Epilepsy is a serious neurological disorder and neurocysticercosis (NCC), the central nervous system infection by the larvae of Taenia solium, is the main cause of acquired epilepsy in developing countries. NCC is becoming more frequent in industrialized countries due to immigration from endemic areas. Previously reported epilepsy incidences range from 30 to 50/100,000 people in industrialized countries and 90 to 122/100,000 people in developing countries., Objectives: To determine the incidence of epilepsy in a cysticercosis endemic area of Peru., Methods: A screening survey for possible seizure cases was repeated biannually in this cohort for a period of 5 years (1999-2004) using a previously validated questionnaire. All positive respondents throughout the study were examined by a trained neurologist in the field to confirm the seizure. If confirmed, they were offered treatment, serological testing, neuroimaging (CT scans and MRI) and clinical follow-up., Results: The cohort study comprised 817 individuals. The overall epilepsy incidence rate was 162.3/100,000 person-years, and for epileptic seizures, 216.6/100,000 person-years. Out of the 8 individuals who had epileptic seizures, 4 had markers for NCC (neuroimaging and/or serology)., Conclusion: The incidence of epilepsy in this area endemic for cysticercosis is one of the highest reported worldwide., ((c) 2009 S. Karger AG, Basel.)

Advances in the field of neurocysticercosis continue to shape our understanding of the disease and our efforts to control it. Several attempts have been made to eradicate the disease with active interventions such as changing domestic pig-raising practices, mass chemotherapy of porcine cysticercosis and taeniasis, selective detection and treatment of taeniasis, and community health education. Moreover, ongoing progress in the diagnosis of taeniasis and the development of a porcine vaccine against cysticercosis in Australia, Mexico and Peru has yielded at least one effective vaccine that is currently available. Thus far, however, attempted interventions have only been successful in temporarily disrupting transmission of the disease. Controlled data on the efficacy and acceptability of the different interventions is urgently needed to provide a base-line schematic for intervention which could later be tailored to each particular endemic scenario.

A matched case-control study on clinical symptoms of Hymenolepis nana and an open trial of nitazoxanide treatment were conducted in a village on the northern coast of Peru. Interview data were obtained from 25 individuals with hymenolepiasis only and 46 matched controls. Individuals with other intestinal helminths or giardiasis were excluded. Twenty nitazoxanide-treated cases were followed with stool examination a month later. There were no significant differences between groups in the prevalence of symptoms except headache, which was less frequent in the cases. Treatment efficacy was 75%. Hymenolepiasis in this community did not have significant impact on specific symptoms.

The seasonal prevalence and container preferences of Aedes albopictus (Skuse) were studied in the park, Parque Mirador del Norte in Santo Domingo City, Dominican Republic, from January to December 1994. Tire ovitraps were set along a transect through the park and monitored weekly while two larval surveys were conducted in both the park and surrounding houses using standard entomological methodology. No seasonal pattern of oviposition was observed with similar numbers of positive tire traps collected in the wet and dry season. Most of the positive ovitraps were located in the middle of the park. Within ovitraps, Aedes aegypti (L.), Ae. albopictus, Culex corniger (Theobald), Ochlerotatus albonotatus (Coquillett), and Toxorhynchites sp. were collected. The larval surveys found 7 associated mosquito species, including Ae. aegypti, Ae. albopictus, Ochleotatus mediovittatus (Coquillett), Anopheles albimanus (Weidemann), Culex nigripalpus (Theobald), and Culex quinquefasciatus Say. The Ae. albopictus breeding sites were plastic buckets (4), rock holes (3), and Styrofoam lunch containers (3). We suggest that further studies should be conducted to determine its geographic distribution and vector potential in the Dominican Republic.

In an effort to develop a more effective measure for use in emergency control of the dengue vector Aedes aegypti. applications of a combination of a larvicide (Bacillus thuringiensis israelensis [B.t.i.]) and an adulticide (permethrin) were made using a truck-mounted forced-air generator (Scorpion 20) and evaluated in the Dominican Republic. This method has the potential to simultaneously control adults and larvae. In bioassay cages placed in household water containers at the time of application, larval mortalities were 95.1 and 100% for 2 application rates of permethrin mixed with B.t.i. Adult mortalities were not as impressive, probably because of resistance to permethrin. Higher adult mortality in caged specimens (78.5%) and a substantial reduction in the natural population (68.4%) of Ae. aegypti were obtained following a 2.1-g AI/ha application of deltamethrin alone.