Lymphatic filariasis in the Philippines

Lymphatic filariasis caused by Wuchereria bancrofti and Brugia malayi is endemic throughout most of the southern half of the Philippine archipelago. Economic and manpower shortages prior to 1996 made it difficult to acquire new prevalence data and vector control data concurrently from all provinces. Nevertheless, analysis of cumulative prevalence data on filariasis indicates the persistence of filariasis in each of the three major island groups - Luzon, Visayas and Mindanao - including 45 out of 77 provinces. Here, Michael Kron and colleagues summarize the prevalence data, and review host, parasite and vector characteristics relevant to the design and implementation of disease control initiatives in the Philippines planned for the year 2000.     

Epidemiology of Cholera in the Philippines

Background

Despite being a cholera-endemic country, data on cholera in the Philippines remain sparse. Knowing the areas where cholera is known to occur and the factors that lead to its occurrence will assist in planning preventive measures and disaster mitigation.

Methods

Using sentinel surveillance data, PubMed and ProMED searches covering information from 2008–2013 and event-based surveillance reports from 2010–2013, we assessed the epidemiology of cholera in the Philippines. Using spatial log regression, we assessed the role of water, sanitation and population density on the incidence of cholera.

Results and Discussion

We identified 12 articles from ProMED and none from PubMed that reported on cholera in the Philippines from 2008 to 2013. Data from ProMed and surveillance revealed 42,071 suspected and confirmed cholera cases reported from 2008 to 2013, among which only 5,006 were confirmed. 38 (47%) of 81 provinces and metropolitan regions reported at least one confirmed case of cholera and 32 (40%) reported at least one suspected case. The overall case fatality ratio in sentinel sites was 0.62%, but was 2% in outbreaks. All age groups were affected. Using both confirmed and suspected cholera cases, the average annual incidence in 2010–2013 was 9.1 per 100,000 population. Poor access to improved sanitation was consistently associated with higher cholera incidence. Paradoxically, access to improved water sources was associated with higher cholera incidence using both suspected and confirmed cholera data sources. This finding may have been due to the breakdown in the infrastructure and non-chlorination of water supplies, emphasizing the need to maintain public water systems.

Conclusion

Our findings confirm that cholera affects a large proportion of the provinces in the country. Identifying areas most at risk for cholera will support the development and implementation of policies to minimize the morbidity and mortality due to this disease.     

Incidence of histoplasmin hypersensitivity in the Philippines

Long-term residents of the Philippines were skin tested with histoplasmin skin test material. This study was conducted with 143 electric company (MERALCO) employees from Manila, Philippines. We found that 37 (26 %) of the subjects were skin test positive. Characteristics of the positive group were: average age of 37 years; all except one were lifelong inhabitants of Metro Manila; 25 were male and 12 were female; one-half of the subjects reported extended contact with chickens. Despite these findings, histoplasmosis is considered to be a very rare disease in the Philippines. This survey indicates that Histoplasma capsulatum is sufficiently present in the Philippines to come in contact withone-fourth of the test population. This reinforces the hypothesis that histoplasmosis is present in the Philippines and is probably being misdiagnosed as granulomatous-inducing diseases such as tuberculosis, e.g., so-called “drug resistant” tuberculosis. We recommend larger surveys of this type and attempts to culture the etiologic agent from natural sources such as chicken and bat droppings. This revised version was published online in July 2006 with corrections to the Cover Date.     

Nematode Problems Affecting Agriculture in the Philippines

Nematodes are considered major pests on most economic crops in the Philippines, particularly on banana, pineapple, citrus, tomato, ramie, and sugarcane. Radopholus similis is the most destructive nematode on banana, while Meloidogyne spp. are more serious on various vegetable crops such as tomato, okra, and celery and on fiber crops such as ramie. Tylenchulus semipenetrans is a problem on citrus and Rotylenchulus reniformis on pineapple and some legume crops. Hirschmanniella oryzae and Aphelenchoides besseyi are becoming serious on rice, and Pratylenchus zeae is affecting corn in some areas. Lately, Globodera rostochiensis has been causing serious damage on potato in the highlands. Control measures such as crop rotation, planting resistant varieties, chemical nematicide application, and biological control have been recommended to control these nematodes.     

Copal and rattan collecting in the Philippines

Minor forest products such as rattan and Manila copal have long been an important source of cash income for indigenous forest collectors in Southeast Asia. Focusing on the Tagbanua of Palawan Island in the Philippines, the history and economic significance of forest collecting in the region are described. The paper also documents the growing scarcity of forest products in Palawan and discusses several policy options intended to help preserve rattan and copal resources.

     

Coral disease dynamics in the central Philippines

Limited quantitative research has been conducted on coral disease in the Philippines and baseline data are much needed. Field surveys for prevalence and distribution patterns were conducted from November 2002 to August 2003. Sites included the islands of Negros, Cebu, Siquijor, Panglao, Olango, Sumilon, Bantayan, Pescador, Balicassag and Palawan. In 154 belt transects, 10 026 Porites colonies were examined at 28 sites covering 3080 m2. Two syndromes, Porites ulcerative white spot (PUWS) and coral tumors, occurred at high prevalence. Tumors as high as 39.1% occurred among massive Porites, and PUWS was as high as 53.7% among massive and branching Porites. In 8 mo, 116 tagged colonies showed slow progression and low mortality. Along a 41 km human impact gradient centered on Dumaguete City (Negros), 15 sites were examined. Correlation analyses linked higher disease prevalence to anthropogenic influence (Spearman's rank correlation coefficient [r(s)] = -0.54, p = 0.04 for tumors and r(s) = -0.69, p = 0.005 for PUWS). In most sites disease prevalence was lower than in the sites near Dumaguete. High PUWS prevalence near uninhabited Sumilon Island appeared to be linked to the highly diseased reefs near Dumaguete City due to transmission of disease along a cross-shelf front formed between the Ta?on Strait and Bohol Sea. Other observations included 12 potential new host species for PUWS (4 new genera and 1 octocorallia) and 5 likely new hosts for black band disease (BBD) in the Philippines, and a relatively high prevalence (7.8%) of BBD in 1 site in western Palawan.     

Status of biomethanation development in the Philippines

Summary Two major agro-industrial enterprizes have commercialized the biomethanation technology in the Philippines: the Maya Farm and the Central Azucarera de Tarlac. The Maya Farm produces biogas from the manure of 25 000 pigs. The reactors are of the batch type. The gas production is used for electricity generation, water pumping and heating, solid wastes drying etc. The Central Azucarera de Tarlac produces biogas from distillery slops and filter cake. The principle of the treatment is decantation followed by thermophilic anaerobic digestion lagooning with and without aeration and finally, irrigation of the sugar-cane fields with the final liquid effluent. The pollution load of the influent is reduced by 80% after anaerobic digestion and by 99% at the end of the treatment. The biogas produced is used to reactivate the spent carbon in the refinery kilns and in the boilers.

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Resumen Dos importantes fábricas agro-industriales han comercializado la técnología de la biometanación en Filipinas: la Granja Maya y la Central Azucarera de Tarlac. La Granja Maya produce biogas a partir del estiercol de 25 000 marranos. Los reactores son de una sola fase. Elagas producido se utiliza para generar electricidad, bombear y calentar agua, secar residuos sólidos, etc. La Central Azucarera de Tarmac produce biogas a partir de desechos de destilerias y de posos de filtrado. El tratamiento consiste en una decantación seguida de una digestión termofílica anaerobia mediante encharcamiento con o sin aereación y finalmente el riego de los campos de caña de azucar con el efluente líquido resultante. El nivel de polución del afluente se reduce en un 80% después de la digestión anaerobia y en un 99% al final del tratamiento. El biogas producido se utiliza para reactivar el carbón gastado en los hornos y calderas de la refinería.

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Résumé Deux importantes agro-industries ont commercialisé, la technologie de la biométhanisation aux Philippines: la ferme Maya et la sucrerie Central Azucarera de Tarlac (CAT). La ferme Maya produit du biogaz à partir du lisier de 25 000 porcs. Les digesteurs sont du type batch et la production de gaz est utilisée pour la production d'électricité, le pompage et le chauffage de l'eau, le séchage, etc. La sucrerie CAT produit du biogaz à partir de boues de distilleries et de gâteaux de filtration. Le principe du traitement est une décantation suivie d'une digestion

     

Groundwater quality in karst regions in the Philippines

Groundwater in karst regions in the Philippines is inhabited by a diverse yet unique aquatic fauna. While this habitat is threatened by anthropogenic disturbances, basic physicochemical information is lacking. Here, we provide the first report of karst groundwater quality based on the characterization and assessment of samples collected from caves. Water samples from seven islands (Bohol, Calicoan, Luzon, Mindanao, Negros Oriental, Panglao, and Samar) were analyzed in order to obtain baseline information about and assess the environmental status of groundwater in karst areas. Although most of the sites showed no evidence of anthropogenic disturbance, excessive amounts of NO₂ ^?, NO₃ ^?, and Cl^? were detected in the samples from a few areas, particularly Panglao Island, Bohol. These pollutants likely originate from human-related activities such as the use of water treatment chemicals, detergents, and bleach, as well as the leakage of septic tanks. Further investigations and in-depth studies aimed at clearly understanding the dynamics of the karst groundwater, thus preventing the aggravation of problems with the groundwater in the future, are highly recommended.     

A Community-Based Validation Study of the Short-Form 36 Version 2 Philippines (Tagalog) in Two Cities in the Philippines

Objective

To evaluate the validity and reliability of the Philippines (Tagalog) Short Form 36 Health Survey version 2 (SF-36v2^®) standard questionnaire among Filipinos residing in two cities.

Study Design and Setting

The official Philippines (Tagalog) SF-36v2 standard (4-week recall) version was pretested on 30 participants followed by formal and informal cognitive debriefing. To obtain the feedback on translation by bilingual respondents, each SF-36v2 question was stated first in English followed by Tagalog. No revisions to the original questionnaire were needed except that participants thought it was appropriate to incorporate "po" in the instructions to make it more polite. Face-to-face interviews of 562 participants aged 20-50 years living in two barangays (villages) in the highly urbanized city of Makati City (Metro Manila) and in urban and rural barangays in Tanauan City (province of Batangas) were subsequently conducted. Content validity, item level validity, reliability and factor structure of the SF-36v2 (Tagalog) were examined.

Results

Content validity of the SF-36v2 was assessed to be adequate for assessing health status among Filipinos. Item means of Philippines (Tagalog) SF-36v2 were similar with comparable scales in the US English, Singapore (English and Chinese) and Thai SF-36 version 1. Item-scale correlation exceeded 0.4 for all items except the bathing item in PF (correlation: 0.31). In exploratory factor analysis, the US two-component model was supported. However, in confirmatory factor analysis, the Japanese three-component model fit the Tagalog data better than the US two-component model.

Conclusions

The Philippines (Tagalog) SF-36v2 is a valid and reliable instrument for measuring health status among residents of Makati City (Metro Manila) and Tanauan City (Province of Batangas).     

Serological analysis of human leptospirosis in the Philippines

Leptospirosis in the Philippines is an underrepresented disease. To achieve an accurate means of serodiagnosis, we demonstrated antibodies to the prevalent Leptospira serovars in sera of 71 patients from three major hospitals in Manila by the microscopic agglutination test and Western blot analysis. Sera of 53 patients contained antibody against 8 serovars poi, tarassovi, manilae, pyrogenes, australis, grippotyphosa, javanica, and autumnalis.     

Fatherhood, pairbonding and testosterone in the Philippines

In species with a high level of paternal care, including humans, testosterone (T) is believed to help mediate the trade-off between parenting and mating effort. This hypothesis is supported by the observation of lower T in pairbonded men or fathers compared to single, non-fathers; however, prior work has highlighted population variation in the association between T and pairbonding or fatherhood status. Here we evaluate this hypothesis in a large (n = 890), representative birth cohort of young men (age range 20.5–22.5 years) living in Cebu City, the Philippines. Bioavailable T was measured in saliva collected prior to bed and immediately upon waking the following morning. Plasma T and luteinizing hormone (LH) were measured in morning plasma samples. In this sample, 20% of men were pairbonded, defined as living with a partner or married, 13% were fathers, and roughly half of fathers reported involvement in childcare. Pairbonded men had significantly lower T at both times of day. Unlike in other populations, this relationship was accounted for entirely by fatherhood status: among the large sub-sample of non-fathers, mean T was nearly identical among pairbonded and single men. There was a strong association between self-reported involvement in childcare and lower evening T, supporting the idea that the evening nadir in T is related to social interactions across the day. Similar relationships were found for total plasma T and LH, suggesting that these relationships are coordinated by centrally-mediated changes in LH secretion. The relatively modest T difference in relation to fatherhood at Cebu, in comparison to other studies, may reflect a lower level of paternal involvement in childcare activities in this population. Our findings using a large, well-characterized birth cohort support the hypothesized role of T as a mediator of mating and parenting effort in humans, while contributing evidence for cultural variation in the relative importance of pairbonding and fathering to these relationships.