Accessibility of Soil-transmitted Helminthiasis Control Strategies in Selected Indigenous People Communities in the Philippines.

Background: Indigenous peoples (IPs) remain vulnerable to soil-transmitted helminthiasis (STH) due to limited access to sanitary toilets, clean water, quality health education, and services. The World Health Organization recommends periodic mass drug administration (MDA) of anthelminthics, health education, and improvements in water, sanitation, and hygiene (WASH) as control strategies to reduce morbidities caused by STH in target populations such as school-age children (SAC).This paper complements the published results of the parasitological survey (prevalence and intensity of STH) conducted in selected Aeta and Ata-Manobo communities. Objectives: This study aimed to describe the accessibility of STH control strategies to respond to the needs of SAC in IP communities in Pampanga and Davao del Norte, the Philippines. It likewise intended to describe access of these IP communities to STH control strategies. Methods: Data on accessibility of and access to STH control strategies were collected using key informant interviews (KIIs) and focus group discussions (FGDs). Eleven officials and workers from the departments of health and education, local government units, and two IP leaders were interviewed on the existing STH burden in SAC, implementation of STH control strategies, particularly of MDA, health education campaigns, and improvements in WASH including good practices and challenges in program implementation.Three FGDs with parents, elementary school teachers of IP schools, and rural health midwives were conducted separately. Guide questions focused on accessibility of and access to STH prevention and control strategies for SAC in IP communities. Informed consent to conduct and record KIIs and FGDs were obtained from participants prior to participation.Analysis of a multi-disciplinary team was based on the accessibility framework for IPs accessing indigenous primary health care services by Davy et al. (2016). Results: The characteristics of the STH control strategies and the target populations are interrelated factors that influence accessibility. Challenges in the availability of the MDA program, particularly, inadequate staffing, drug shortages, and delays in delivery affect accessibility of and access to the free STH control strategies. Perceived harm, adverse events, stigma, beliefs, and practices likewise affect access. Lack of information on the similarity of treatment through community- and school-based MDA programs also affected engagement of SAC.IP communities are special settings where geographic isolation, peace and order situation as well as water supply need to be considered to help ensure access to STH control strategies, high MDA coverage, and improvements in WASH leading to desired outcomes. Conclusions: Considering the context of IP communities and addressing the challenges in the accessibility of and access to STH control strategies are necessary to ensure successful implementation of an integrated approach in STH prevention and control strategies. Challenges in the accessibility of STH control strategies are inadequate staffing, poor inventory, and delays in the delivery of drugs, as well as poor sanitation and hygiene. Access of SAC is likewise affected by misconceptions on safety and efficacy of anthelminthics, including stigma and cultural practices. The similarity of the MDA programs based in school or community need to be disseminated.

Worldwide absence of canonical benzimidazole resistance-associated mutations within ß-tubulin genes from Ascaris.

BACKGROUND: The giant roundworm Ascaris is an intestinal nematode, causing ascariasis by infecting humans and pigs worldwide. Recent estimates suggest that Ascaris infects over half a billion people, with chronic infections leading to reduced growth and cognitive ability. Ascariasis affects innumerable pigs worldwide and is known to reduce production yields via decreased growth and condemnation of livers. The predominant anthelminthic drugs used to treat ascariasis are the benzimidazoles. Benzimidazoles interact with ß-tubulins and block their function, and several benzimidazole resistance-associated mutations have been described in the ß-tubulins of ruminant nematodes. Recent research on ascarids has shown that these canonical benzimidazole resistance-associated mutations are likely not present in the ß-tubulins of Ascaris, Ascaridia or Parascaris, even in phenotypically resistant populations. METHODS: To further determine the putative absence of key ß-tubulin polymorphisms, we screened two ß-tubulin isotypes of Ascaris, highly expressed in adult worms. Using adult and egg samples of Ascaris obtained from pigs and humans worldwide, we performed deep amplicon sequencing to look for canonical resistance-associated mutations in Ascaris ß-tubulins. Subsequently, we examined these data in closer detail to study the population dynamics of Ascaris and genetic diversity within the two isotypes and tested whether genotypes appeared to partition across human and pig hosts. RESULTS: In the 187 isolates, 69 genotypes were found, made up of eight haplotypes of ß-tubulin isotype A and 20 haplotypes of isotype B. Single nucleotide polymorphisms were seen at 14 and 37 positions for ß-tubulin isotype A and isotype B, respectively. No evidence of any canonical benzimidazole resistance-associated mutations was found in either human- or pig-derived Ascaris isolates. There was, however, a difference in the genetic diversity of each isotype and distribution of ß-tubulin genotypes between human- and pig-derived Ascaris. Statistical tests of population differentiation show significant differences (p < 0.001) between pig- and human-derived worms; however, more diversity was seen between worms from different populations than worms from different hosts. CONCLUSIONS: Our work suggests an absence of canonical ß-tubulin mutations within Ascaris, but alternative modes of anthelminthic resistance may emerge necessitating continued genetic scrutiny alongside monitoring of drug efficacy.

Low schistosomiasis and soil-transmitted helminthiasis prevalence and intensities in selected communities in Davao de Oro and Davao del Norte, the Philippines: A setting for interruption of transmission?

Parasitic neglected tropical diseases, such as schistosomiasis and soil-transmitted helminthiasis (STH), remain as significant public health concerns in developing countries such as the Philippines. This study aimed to determine the prevalence and intensity of schistosomiasis and STH among school-age children (SAC) and adults in two co-endemic provinces in Mindanao in southern Philippines as part of monitoring of national control programs. Stool samples were collected, processed using Kato-Katz technique, and examined microscopically for presence of intestinal helminth ova. A total of 776 SAC and 526 adults participated in the study. Low schistosomiasis prevalence was generally observed in SAC (0.8%) and adults (0.4%). Generally low STH prevalence was reported in both SAC (3.9%) and adults (3.4%). Only three SAC had heavy intensity STH, which was not seen in adults. Results indicate a state of good morbidity control, which may be a result of effective implementation of mass drug administration (MDA) strategy for schistosomiasis, STH, and lymphatic filariasis in the last several years. The low prevalence and intensities of infections may also be partly attributed to the low diagnostic sensitivity of Kato-Katz technique in detecting low intensity intestinal helminth infections. While results of this study also indicate similarly low levels of both these infections in previous studies, sustaining high MDA coverage rates and addressing remaining challenges related to intensified case finding and treatment, improvements in safe water, sanitation, and hygiene, veterinary public health, and vector ecology and management will be necessary to interrupt transmission in these areas.

A Qualitative Study on the Implementation of the Workplace TB Program in the Philippines: Challenges and Way Forward.

Tuberculosis (TB) is a chronic infectious disease that remains to be a primary health concern globally. The Philippines is among the top TB-burdened countries. Workplace TB prevention and control programs are essential to ensure the health and safety of workers and economic security. There remains a knowledge gap regarding the Philippine workplace TB prevention and control program implementation. This qualitative study involving key informant interviews reviewed the implementation of the workplace TB program in selected companies in a high TB burden region in Eastern Philippines. Results were presented under four themes in accordance with the components of the workplace TB policy: preventive strategies, medical management, data recording and reporting, and social policy. Various good practices, opportunities, and challenges in the implementation of the workplace TB program were identified. There is a need to strengthen the enforcement of policy across different components. Compliance with guidelines on preventive strategies and recording and reporting schemes needs to be intensified. Coordination across different levels and agencies may also be enhanced to allow more efficient implementation. Increased awareness of corporate decision-makers may improve company ownership of the program leading to improved implementation while increased awareness of employees on their rights and entitlements may likewise enhance compliance.

Critical medical ecology and intersectionality perspectives in schistosomiasis prevention and control in selected communities in Mindanao, the Philippines.

Schistosomiasis japonica remains a public health concern in many areas of the Philippines. Periodic Mass Drug Administration (MDA) to at-risk populations is the main strategy for morbidity control of schistosomiasis. Attaining MDA coverage targets is important for the reduction of morbidity and prevention of complications due to the disease, and towards achieving Universal Health Care. The study employed a qualitative case study design. Key informant interviews and focus group discussions were conducted to provide in-depth and situated descriptions of the contexts surrounding the implementation of MDA in two selected villages in known schistosomiasis-endemic provinces in Mindanao in the Philippines. Data analysis was done using the Critical Ecology for Medical Anthropology (CEMA) model coupled with the intersectionality approach. It was found that within various areas in the CEMA model, enabling as well as constraining factors have been encountered in MDA in the study settings. The interplay of income class, geographical location, gender norms and faith-based beliefs may have led to key populations being missed during the conduct of MDA in the study sites. The constraints faced by the target beneficiaries of MDA, as well as programme implementers, must be addressed to enhance service delivery and to control morbidity due to schistosomiasis. Improving compliance with MDA also requires a holistic, integrated approach to addressing barriers to participation, which are shaped by wider socio-political and power structures.

Co-infection of intestinal helminths in humans and animals in the Philippines.

BACKGROUND: A large number of studies have assessed risk factors for infection with soil-transmitted helminths (STH), but few have investigated the interactions between the different parasites or compared these between host species across hosts. Here, we assessed the associations between Ascaris, Trichuris, hookworm, strongyle and Toxocara infections in the Philippines in human and animal hosts. METHODS: Faecal samples were collected from humans and animals (dogs, cats and pigs) in 252 households from four villages in southern Philippines and intestinal helminth infections were assessed by microscopy. Associations between worm species were assessed using multiple logistic regression. RESULTS: Ascaris infections showed a similar prevalence in humans (13.9%) and pigs (13.7%). Hookworm was the most prevalent infection in dogs (48%); the most prevalent infection in pigs was strongyles (42%). The prevalences of hookworm and Toxocara in cats were similar (41%). Statistically significant associations were observed between Ascaris and Trichuris and between Ascaris and hookworm infections in humans, and also between Ascaris and Trichuris infections in pigs. Dual and triple infections were observed, which were more common in dogs, cats and pigs than in humans. CONCLUSIONS: Associations are likely to exist between STH species in humans and animals, possibly due to shared exposures and transmission routes. Individual factors and behaviours will play a key role in the occurrence of co-infections, which will have effects on disease severity. Moreover, the implications of co-infection for the emergence of zoonoses need to be explored further.

Evaluation of loop-mediated isothermal amplification assay and enzyme-linked immunosorbent assay in detecting Schistosoma japonicum in Siargao Island, Surigao del Norte, the Philippines.

OBJECTIVES: This study aimed to describe the prevalence and seroprevalence of schistosomiasis in Siargao Island, Surigao del Norte and to compare the performance of enzyme-linked immunosorbent assay antibody test (ELISA Ab) and loop-mediated isothermal amplification assay (LAMP) for diagnosis of schistosomiasis. METHODS: The study was conducted in selected barangays (villages) in five municipalities in Siargao Island, Surigao del Norte and included school-age children (SAC) who submitted stool and blood samples. Stool samples were examined using the Kato-Katz technique. Blood samples were collected through venipuncture. The stool samples and the blood samples collected were tested using LAMP assay and polymerase chain reaction (PCR). The blood samples were examined using ELISA Ab. Diagnostic performance of LAMP assay using stool specimen was evaluated using Kato-Katz technique and PCR assay as the composite reference standard, while PCR assay was used as the reference standard to evaluate LAMP assay and ELISA Ab using blood specimens. RESULTS: A total of 417 stool samples from SAC were examined. The prevalence of schistosomiasis and moderate-heavy intensity (MHI) schistosomiasis were 3.8% and 1.4%, respectively. Schistosomiasis and soil-transmitted helminthiases (STH) coinfection prevalence were 2.6%. A total of 425 blood samples were examined using ELISA Ab. Seroprevalence was 61.6%. The municipality of San Isidro had the highest seroprevalence at 84.8%, while Burgos had the lowest seroprevalence at 48.5%.LAMP assay had higher sensitivity and positive predictive value but lower specificity when using stool than when using blood samples. Its negative predictive value was similar regardless of the specimen used. ELISA Ab has higher sensitivity and negative predictive value than LAMP assay although it has lower specificity and positive predictive value. This may be due to ELISA Ab measuring Schistosoma exposure and is thus unable to distinguish past from active infection. CONCLUSIONS: Schistosomiasis remains a public health concern in Siargao Island, Surigao del Norte. The locally developed LAMP assay offers a simpler diagnostic test for schistosomiasis compared with PCR, while minimizing the risk of misdiagnosis compared with Kato-Katz technique. It could serve as a point of care diagnostics for schistosomiasis. ELISA Ab is more useful in surveillance particularly in low-endemicity areas where determination of exposure is more important than differentiating past from active infection. ELISA Ab may be helpful in the clinical setting when coupled with the expertise of a physician who is familiar with schistosomiasis.

Prevalence of soil-transmitted helminth infections, schistosomiasis, and lymphatic filariasis before and after preventive chemotherapy initiation in the Philippines: A systematic review and meta-analysis.

OBJECTIVE: To estimate the impact of preventive chemotherapy on the prevalence and intensity of soil-transmitted helminth (STH) infections, schistosomiasis, and lymphatic filariasis in the Philippines, using systematic review and meta-analysis. METHODS: We included reports reporting prevalence of STH infections, schistosomiasis, or lymphatic filariasis in the Philippines published until 31 March 2021. Peer-reviewed studies were identified in electronic databases. Grey literature reports by the University of the Philippines and the Department of Health were also included. Pooled infection prevalence, before and after the initiation of preventive chemotherapy, stratified by age group, was calculated using the inverse variance heterogeneity model. FINDINGS: A total of 109 reports were included in the review and meta-analysis. Overall prevalence of moderate-heavy intensity Ascaris lumbricoides (6.6%) and Trichuris trichiura (2.7%) infection after initiation of preventive chemotherapy were significantly lower than the prevalence prior to initiation (23.6% for A. lumbricoides and 12.2% for T. trichiura). Prevalence reductions were also found in school and preschool-age children for A. lumbricoides and T. trichiura. Studies conducted after preventive chemotherapy initiation had significantly lower overall prevalence of moderate-heavy intensity schistosomiasis (3.1% vs 0.2%) and of schistosomiasis in school-age children (30.5% vs 1%). Pooled prevalence of lymphatic filariasis prior to preventive chemotherapy initiation was 3.2% across 12 provinces, while currently only two provinces still have prevalence of more than 1%. There were no published studies reporting prevalence of lymphatic filariasis after initiation of preventive chemotherapy. Heterogeneity was high with I2 mostly above 90%. CONCLUSION: The burden of STH infections and schistosomiasis in children were significantly lower in studies conducted following the initiation of preventive chemotherapy. Eliminating morbidity and interrupting transmission, however, may require expanded control initiatives including community-wide treatment, and improved water, sanitation, and hygiene. Lymphatic filariasis burden has decreased since the implementation of preventive chemotherapy, with all but two provinces having reached the elimination of lymphatic filariasis as a public health problem.

Sensitive and semiquantitative detection of soil-transmitted helminth infection in stool using a recombinase polymerase amplification-based assay.

BACKGROUND: Soil-transmitted helminths (STHs) are parasitic nematodes that inhabit the human intestine. They affect more than 1.5 billion people worldwide, causing physical and cognitive impairment in children. The global strategy to control STH infection includes periodic mass drug administration (MDA) based on the results of diagnostic testing among populations at risk, but the current microscopy method for detecting infection has diminished sensitivity as the intensity of infection decreases. Thus, improved diagnostic tools are needed to support decision-making for STH control programs. METHODOLOGY: We developed a nucleic acid amplification test based on recombinase polymerase amplification (RPA) technology to detect STH in stool. We designed primers and probes for each of the four STH species, optimized the assay, and then verified its performance using clinical stool samples. PRINCIPAL FINDINGS: Each RPA assay was as sensitive as a real-time polymerase chain reaction (PCR) assay in detecting copies of cloned target DNA sequences. The RPA assay amplified the target in DNA extracted from human stool samples that were positive for STH based on the Kato-Katz method, with no cross-reactivity of the non-target genomic DNA. When tested with clinical stool samples from patients with infections of light, moderate, and heavy intensity, the RPA assays demonstrated performance comparable to that of real-time PCR, with better results than Kato-Katz. This new rapid, sensitive and field-deployable method for detecting STH infections can help STH control programs achieve their goals. CONCLUSIONS: Semi-quantitation of target by RPA assay is possible and is comparable to real-time PCR. With proper instrumentation, RPA assays can provide robust, semi-quantification of STH DNA targets as an alternative field-deployable indicator to counts of helminth eggs for assessing infection intensity.

A mathematical model of the dynamics of lymphatic filariasis in Caraga Region, the Philippines.

Despite being one of the first countries to implement mass drug administration (MDA) for elimination of lymphatic filariasis (LF) in 2001 after a pilot study in 2000, the Philippines is yet to eliminate the disease as a public health problem with 6 out of the 46 endemic provinces still implementing MDA for LF as of 2018. In this work, we propose a mathematical model of the transmission dynamics of LF in the Philippines and a control strategy for its elimination using MDA. Sensitivity analysis using the Latin hypercube sampling and partial rank correlation coefficient methods suggests that the infected human population is most sensitive to the treatment parameters. Using the available LF data in Caraga Region from the Philippine Department of Health, we estimate the treatment rates r 1 and r 2 using the least-squares parameter estimation technique. Parameter bootstrapping showed small variability in the parameter estimates. Finally, we apply optimal control theory with the objective of minimizing the infected human population and the corresponding implementation cost of MDA, using the treatment coverage γ as the control parameter. Simulation results highlight the importance of maintaining a high MDA coverage per year to effectively minimize the infected population by the year 2030.

High burden of soil-transmitted helminth infections, schistosomiasis, undernutrition, and poor sanitation in two Typhoon Haiyan-stricken provinces in Eastern Philippines.

This study aimed to describe: 1) soil-transmitted helminthiasis (STH) and schistosomiasis prevalence and intensity in preschool-age children (PSAC) and school-age children (SAC), 2) schistosomiasis seroprevalence in SAC, 3) undernutrition prevalence in SAC, 4) sanitary toilet coverage in households, and 5) association between STH, Schistosoma japonicum exposure, nutritional status, and sanitation. PSAC and SAC in two Haiyan-stricken provinces were examined using Kato-Katz technique and ELISA Antibody test. Anthropometric and hemoglobin measurements were also obtained. The reported sanitary toilet coverage was validated in a survey. The prevalence of any STH in PSAC and SAC was 50.2% and 41.3%, respectively. Moderate-heavy intensity (MHI) STH prevalence in PSAC and SAC was 20.8% and 5.9%, respectively. The prevalence of any STH, MHI STH, ascariasis, MHI ascariasis, and MHI trichuriasis was significantly higher in PSAC. Stunting, underweight, wasting, overweight/obesity, and anemia prevalence was 38.4%, 24.5%, 4.8%, 2.7%, and 34.7% in PSAC, while the prevalence was 34.3%, 21.6%, 8.7%, 3.0%, and 19.2% in SAC, respectively. Anemia and wasting prevalence were significantly higher in PSAC and SAC, respectively. There were five schistosomiasis cases found (0.8% prevalence), while schistosomiasis seroprevalence was 60.1%. Validated and reported sanitary toilet coverage was significantly different in eight out of 13 barangays. Stunting and anemia were associated with STH. STH and anemia prevalence were significantly higher in non-ZOD barangays. High STH burden in PSAC and SAC persists. A more coordinated response addressing STH, undernutrition, and WASH in disaster-stricken areas will require strengthening local health systems and promoting intersectoral collaboration.

Use of geographic information system as a tool for schistosomiasis surveillance in an endemic Municipality in Eastern Samar, The Philippines.

This study aimed to demonstrate the use of geographic information systems (GIS) in identifying factors contributing to schistosomiasis endemicity and identifying high-risk areas in a schistosomiasis- endemic municipality in the Philippines, which was devastated by Typhoon Haiyan in 2013. Data on schistosomiasis determinants, obtained through literature review, the Philippine Department of Health, and concerned local government units, were standardized and incorporated into a GIS map using ArcGIS. Data gathered included modifiable [agriculture, poverty, sanitation, presence of intermediate and reservoir hosts, disease prevalence and mass drug administration (MDA) coverage] and nonmodifiable (geography and climate) determinants for schistosomiasis. Results showed that most barangays (villages) are characterized by favourable conditions for schistosomiasis transmission which include being located in flood-prone areas, presence of vegetation, low sanitary toilet coverage, presence of snail intermediate host, high carabao (water buffalo) population density, previously reported ≥1% prevalence using Kato-Katz technique, and low MDA coverage. Similarly, barangays not known to be endemic for schistosomiasis but also characterized by the same favourable conditions for schistosomiasis as listed above and may therefore be considered as potentially endemic, even if not being high-risk areas. This study demonstrated the importance of GIS technology in characterizing schistosomiasis transmission. Maps generated through application of GIS technology are useful in guiding program policy and planning at the local level for an effective and sustainable schistosomiasis control and prevention.

Health and Education Officials' Perspectives on the Impact of Typhoon Haiyan on Mass Drug Administration for Soil-Transmitted Helminth Infections in the Philippines.

OBJECTIVES: In the Philippines, morbidity control of soil-transmitted helminth (STH) infections is done through mass drug administration (MDA) of anthelmintics to school-age children (SAC). In 2013, the Philippines was devastated by the deadliest cyclone ever recorded, Typhoon Haiyan. The study aimed to understand the impact of Typhoon Haiyan on the MDA of anthelmintics to SAC in the provinces of Capiz and Iloilo in the Philippines from the perspectives of local health and education officials. METHODS: The study was conducted in the municipalities of Panay and Pilar in Capiz and the municipalities of Estancia and Sara in Iloilo, areas that were devastated by Typhoon Haiyan. Qualitative, semi-structured key informant interviews were conducted with 16 total participants, which included officials of the Department of Health, Department of Education, and concerned local government units. All interviews were transcribed verbatim and coded in an open, iterative manner. Codes were reviewed to identify patterns and themes. RESULTS: Participants described the following themes: (1) their perception that the typhoon had no effect on the MDA program or on resources necessary to complete the program; (2) the program's simple design allowed for 1-time administration to a pre-assembled population; (3) the program allowed a sense of community cohesiveness; (4) the program served as a vehicle for altruism, particularly regarding helping needy children, in this time of calamity. CONCLUSIONS: Our informants perceived that the MDA program in Region VI was not affected by Typhoon Haiyan. They attributed the resilience to the program's simple procedure, attitudes of altruism, program importance, and community cohesiveness. Despite Typhoon Haiyan's mass destruction of infrastructure and livelihood leading to incredible challenges, mobilization of the community allowed for the continuation and successful implementation of the MDA program. The experience of Region VI may serve as a model for other low- and middle-income countries prone to natural disasters.

Zoonotic transmission of intestinal helminths in southeast Asia: Implications for control and elimination.

Intestinal helminths are extremely widespread and highly prevalent infections of humans, particularly in rural and poor urban areas of low and middle-income countries. These parasites have chronic and often insidious effects on human health and child development including abdominal problems, anaemia, stunting and wasting. Certain animals play a fundamental role in the transmission of many intestinal helminths to humans. However, the contribution of zoonotic transmission to the overall burden of human intestinal helminth infection and the relative importance of different animal reservoirs remains incomplete. Moreover, control programmes and transmission models for intestinal helminths often do not consider the role of zoonotic reservoirs of infection. Such reservoirs will become increasingly important as control is scaled up and there is a move towards interruption and even elimination of parasite transmission. With a focus on southeast Asia, and the Philippines in particular, this review summarises the major zoonotic intestinal helminths, risk factors for infection and highlights knowledge gaps related to their epidemiology and transmission. Various methodologies are discussed, including parasite genomics, mathematical modelling and socio-economic analysis, that could be employed to improve understanding of intestinal helminth spread, reservoir attribution and the burden associated with infection, as well as assess effectiveness of interventions. For sustainable control and ultimately elimination of intestinal helminths, there is a need to move beyond scheduled mass deworming and to consider animal and environmental reservoirs. A One Health approach to control of intestinal helminths is proposed, integrating interventions targeting humans, animals and the environment, including improved access to water, hygiene and sanitation. This will require coordination and collaboration across different sectors to achieve best health outcomes for all.

Identification of suspected paragonimiasis-endemic foci using a questionnaire and detection of Paragonimus ova using the Ziehl-Neelsen technique in Zamboanga Region, the Philippines.

Improving paragonimiasis surveillance, which is crucial for disease control, requires adopting new tools and techniques useful in mapping endemic areas. This study aimed to (1) develop a questionnaire to identify suspected paragonimiasis-endemic foci, (2) describe the epidemiology of paragonimiasis, and (3) evaluate Ziehl-Nielsen Staining technique (ZNS) in detecting Paragonimus ova. The questionnaire, which municipal health officers filled out, was based on proposed site inclusion criteria utilized in the integrated tuberculosis (TB)-paragonimiasis surveillance and control project. Newly deployed medical technologists in Zamboanga Region underwent training, which included laboratory diagnosis of paragonimiasis using preserved and fresh specimens and an integrated tuberculosis-paragonimiasis survey in nine selected barangays (villages). Paragonimiasis cases were found in seven out of the nine barangays identified by the questionnaire. Of the 373 patients, three (0.80%) were TB-positive, and 29 (7.77%) were paragonimiasis-positive. The highest paragonimiasis prevalence (27%) was found in Barangay Libato. Ziehl-Neelsen Staining technique (ZNS) correctly detected 8 out of the 29 samples positive (sensitivity - 27.59%; 95% CI: 12.73-47.24%) and all the 334 samples negative (specificity - 100%; 95% CI: 98.90-100%) for Paragonimus ova. The questionnaire may be improved by refining the inclusion criteria. In paragonimiasis-endemic areas, the ZNS and the NaOH concentration technique may be used for detecting Paragonimus ova. Modifying the ZNS, for instance by including a concentration step, may improve its sensitivity. The model for the integrated capacity building of health workers and surveillance and research demonstrated in this project may contribute to improving surveillance and control of paragonimiasis and other neglected tropical diseases.

Formative research to inform development of a new diagnostic for soil-transmitted helminths: Going beyond the laboratory to ensure access to a needed product.

Soil-transmitted helminths (STHs) affect more than 1.5 billion people. The global strategy to control STH infections requires periodic mass drug administration (MDA) based on prevalence among populations at risk determined by diagnostic testing. Widely used copromicroscopy methods to detect infection, however, have low sensitivity as the prevalence and intensity of STH infections decline with repeated MDA. More sensitive diagnostic tools are needed to inform program decision-making. Using an integrated product development process, PATH conducted qualitative and quantitative formative research to inform the design and development of a more sensitive test for STH infections. The research, grounded in a conceptual framework for ensuring access to health products, involved stakeholder analysis, key opinion leader interviews, observational site visits of ongoing STH surveillance programs, and market research including market sizing, costing and willingness-to-pay analyses. Stakeholder analysis identified key groups and proposed strategic engagement of stakeholders during product development. Interviews highlighted features, motivations and concerns that are important for guiding design and implementation of new STH diagnostics. Process mapping outlined current STH surveillance workflows in Kenya and the Philippines. Market sizing in 2016 was estimated around half a million tests for lower STH burden countries, and 1-2 million tests for higher STH burden countries. The cost of commodities per patient for a molecular STH diagnostic may be around $10, 3-4 times higher than copromicroscopy methods, though savings may be possible in time and staffing requirements. The market is highly price sensitive as even at $5 per test, only 27% of respondents thought the test would be used by surveillance programs. A largely subsidized STH control strategy and a semi-functional Kato-Katz test may have created few incentives for manufacturers to innovate in STH diagnostics. Diverse partnerships, as well as balancing needs and expectations for new STH diagnostics are necessary to ensure access to needed products.

Child development center-based sentinel surveillance of soil-transmitted helminthiases in preschool-age children in selected local government units in the Philippines.

Soil-transmitted helminthiasis (STH) remains a public health concern in developing countries, such as the Philippines. Preschool-age children (PSAC) are among the high-risk groups for STH. Data on the status of STH in PSAC are needed to help guide policy formulation and program implementation; however, in the usual setting, such data may remain limited. This study aimed to describe the parasitologic status of PSAC in selected local government units (LGUs) in the Philippines through sentinel surveillance methodology in a child-development center (CDC)-based setting. This cross-sectional study, which included 1732 PSAC in selected barangays (a village or the smallest administrative unit in the country) in the provinces of Cavite, Guimaras, Iloilo, Negros Occidental, and Davao del Norte and cities of Iloilo and Lapu-Lapu in the Philippines, utilized Kato-Katz technique to determine parasitologic status. A single Kato-Katz smear was prepared from the adult-thumb sized stool sample submitted by each participant. Ten percent of Kato-Katz slides examined by field microscopists were re-examined by a reference microscopist as part of quality control. Results showed a prevalence of any STH infection and a moderate-heavy ((M-H)) intensity prevalence of 24.9% and 10.3%, respectively. Five cases of schistosomiasis were found in Lapu-Lapu City and Davao del Norte. While the Philippines' Department of Health (DOH) - Integrated Helminth Control Program (IHCP) target for prevalence of any STH of less than 50% was attained, none of the barangays or villages met the World Health Organization (WHO) target for (M-H) intensity STH prevalence of less than 1%, despite the program being implemented for almost a decade. Sentinel surveillance in PSAC, possibly adopting a CDC-based approach, may be implemented biannually in the Philippines and other countries where a similar early child care development system exist to generate data needed to guide policy formulation and program implementation. Preventive chemotherapy through facility-based mass drug administration (MDA), such as CDC-based MDA, may be explored to improve the mode of MDA delivery and coverage in PSAC.