Dengue in Timor-Leste during the COVID-19 phenomenon.

Dengue is a significant public health problem in mostly tropical countries, including Timor-Leste. Dengue continues to draw attention from the health sector during the COVID-19 phenomenon. Therefore, the goal of this study is to evaluate the dengue incidence rate in comparison with the COVID-19 cumulative number and associated dengue risk factors, including the fatality rate of dengue infection in each municipality during the COVID-19 phenomenon in Timor-Leste, by applying the data processing program in Geographic Information Systems (GIS). A descriptive study using GIS was performed to provide a spatial-temporal mapping of dengue cases. Secondary data, which were sourced from the Department of Health Statistics Information under the Ministry of Health Timor-Leste, were collected for the period during the COVID-19 outbreak in 2020-2021. These data were grounded at the municipal (province) level. Quantum GIS and Microsoft Excel were used to analyze the data. During the COVID-19 outbreak (2020-2021), dengue spread nationwide. It was found that there was an increase in municipalities with high dengue cases and cumulative COVID-19 numbers. The high number of dengue cases associated with the COVID-19 cumulative number found in municipalities with an urban characteristic and in terms of severity, dengue fever (DF) is most commonly reported with a total of 1,556 cases and is followed by dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). Most cases were reported in the months of the monsoon season, such as December, January, and March. Dengue GIS mapping helps understand the disease's presence and dynamic nature over time.

Factors affecting preventive behavior against leptospirosis among the population at risk in Si Sa Ket, Thailand.

Leptospirosis is a major public health problem in Si Sa Ket, Thailand. Humans can become infected via direct contact with the urine of infected animal reservoir hosts or by indirect contact with contaminated soil and water in the environment. This study examined the factors affecting preventive behavior against leptospirosis among the population at risk in Si Sa Ket, Thailand. A cross-sectional questionnaire was conducted by a representative population survey using a four-stage stratified random sampling to select 350 respondents aged 18-65 years from the fifth districts with the highest morbidity rate in 2010-2019. Data were analyzed by descriptive statistics and stepwise multiple regression. The majority of the respondents were male (53.40%), aged 46-55 years (31.20%), and agricultural workers (76.00%). Their knowledge (M = 10.78, SD = 1.60), perceived severity (M = 2.91, SD = 0.60), perceived probability (M = 2.98, SD = 0.64), self-efficacy expectations (M = 3.18, SD = 0.63), responses-efficacy expectations (M = 3.16, SD = 0.71), social support (M = 3.19, SD = 0.52), and preventive behavior against leptospirosis (M = 3.29, SD = 0.49) were at moderate level. Significant factors affecting leptospirosis preventive behaviors were history of leptospirosis illness (ß = 0.312), social support (ß = 0.240), perceived probability (ß = 0.238), household members with a history of leptospirosis illness (ß = 0.158), perceived severity (ß = 0.114), self-efficacy expectations (ß = 0.094) and knowledge (ß = 0.088) regarding leptospirosis. All of these factors could together predict the preventive behavior against leptospirosis up to 42.8% (Adjusted R2 = 0.428). Public health interventions should be strengthening people's perception and awareness regarding leptospirosis and the promotion of preventive health behavior to prevent potential outbreaks.

Current status of helminthiases in Thailand: A cross-sectional, nationwide survey, 2019.

Helminthiases are common neglected tropical diseases in Thailand, thus regular surveillance is necessary for their control. During fiscal year 2019, the Thailand Ministry of Public Health carried out a cross-sectional nationwide survey in people of all age groups from the 12 Regional Health Offices in 76 provinces of Thailand. Multi-stage cluster random sampling design was employed to assess the prevalence of helminth infections and certain behavioural risk factors. A total of 16,187 stool samples and demographic data were obtained from the participants. Stool examination was done and parasite eggs/lavae were identified microscopically by experienced technicians. Positive stool samples for Opisthorchis viverrini, hookworms, or Ascaris lumbricoides were further quantified and expressed in eggs per gram feces (EPG). The results revealed an overall prevalence of helminthic infections of 9.79% with over 14 species identified. The highest prevalence was hookworms (4.47%) followed by O. viverrini (2.2%) with mean infection intensities of 222.7 EPG and 120.9, respectively. The majority of the infections were low intensity (97.4% for hookworms and 99.1% for O. viverrini). Similarly for A. lumbricoides, 93.9% of the positive cases were low infections. Two major helminthiases caused by hookworms and O. viverrini were highlighted in this report. While the liver fluke was highly endemic in Northeast Thailand, the hookworms were prevalent in the southmost region of the country. Association with demographic characteristics and risk behaviors of the two parasites were analyzed and presented in this study. Overall, this countrywide survey provides basic information of the current status of helminth infections in Thailand. Moreover, the data clearly indicates a dramatic reduction of O. viverrini prevalence likely due to extensive control activities under the national campaign against the liver fluke over the past five years.

Model-based spatial-temporal mapping of opisthorchiasis in endemic countries of Southeast Asia.

Opisthorchiasis is an overlooked danger to Southeast Asia. High-resolution disease risk maps are critical but have not been available for Southeast Asia. Georeferenced disease data and potential influencing factor data were collected through a systematic review of literatures and open-access databases, respectively. Bayesian spatial-temporal joint models were developed to analyze both point- and area-level disease data, within a logit regression in combination of potential influencing factors and spatial-temporal random effects. The model-based risk mapping identified areas of low, moderate, and high prevalence across the study region. Even though the overall population-adjusted estimated prevalence presented a trend down, a total of 12.39 million (95% Bayesian credible intervals [BCI]: 10.10-15.06) people were estimated to be infected with O. viverrini in 2018 in four major endemic countries (i.e., Thailand, Laos, Cambodia, and Vietnam), highlighting the public health importance of the disease in the study region. The high-resolution risk maps provide valuable information for spatial targeting of opisthorchiasis control interventions.

Discovery of Carcinogenic Liver Fluke Metacercariae in Second Intermediate Hosts and Surveillance on Fish-Borne Trematode Metacercariae Infections in Mekong Region of Myanmar.

Countries of lower Mekong regions are highly alarmed by the spread of fish-borne trematode infections, i.e., small liver flukes and minute intestinal flukes especially in Thailand, Lao People's Democratic Republic (Lao PDR), Vietnam, Cambodia and Myanmar. Moreover; the incidence of cholangiocarcinoma has also been increasing in the endemic area of liver fluke infections. Only a few reports have been published concerning the fish-borne trematodes infections in the central region of Myanmar. However; there is still a lack of information regarding the status of trematodes infections in second intermediate hosts in the Mekong region of Myanmar. Therefore, we conducted surveillance on the distribution of trematode metacercariae in small cyprinoid fishes collected from the Mekong region of Myanmar. A total of 689 fishes (12 different species of cyprinoid fishes) have been collected and examined by pepsin digestion methods. We discovered four species of fish-borne trematode metacercariae infections, i.e., carcinogenic liver fluke, Opisthorchis viverrini; minute intestinal flukes, Haplorchis taichui; Haplorchis pumilio and Haplorchoides sp. in Tachileik, the Mekong Region of Myanmar. The outcome of this study could be a useful index for the fish-borne zoonotic trematode epidemiology in the Mekong area. Besides, the results of our study contribute to filling the gap of information necessary for the control and prevention of fish-borne trematode zoonotic infections in the Mekong region.

Co-infection with Opisthorchis viverrini and Haplorchis taichui detected by human fecal examination in Chomtong district, Chiang Mai Province, Thailand.

Diseases caused by the liver fluke, Opisthorchis viverrini and the minute intestinal fluke, Haplorchis taichui, are clinically important, especially in the Northeast and North regions of Thailand. It is often difficult to distinguish between these trematode species using morphological methods due to the similarity of their eggs and larval stages both in mixed and co-infections. A sensitive, accurate, and specific detection method of these flukes is required for an effective epidemiological control program. This study aimed to determine the prevalence of O. viverrini and H. taichui infections in human feces by using formalin-ether sedimentation and high annealing temperature random amplified polymorphic DNA (HAT-RAPD) PCR methods. Fecal specimens of people living along the Mae Ping River, Chomtong district were examined seasonally for trematode eggs using a compound microscope. Positive cases were analyzed in HAT-RAPD, DNA profiles were compared with adult stages to determine the actual species infected, and specific DNA markers of each fluke were also screened. Our results showed that out of 316 specimens, 62 were positive for fluke eggs which were pre-identified as O. viverrini and H. taichui. In addition, co-infection among these two fluke species was observed from only two specimens. The prevalence of H. taichui infections peaked in the hot-dry (19.62%), gradually decreased in the rainy (18.18%), and cool-dry seasons (14.54%), respectively. O. viverrini was found only in the hot-dry season (6.54%). For molecular studies, 5 arbitrary primers (Operon Technologies, USA) were individually performed in HAT-RAPD-PCR for the generation of polymorphic DNA profiles. The DNA profiles in all 62 positives cases were the same as those of the adult stage which confirmed our identifications. This study demonstrates the mixed infection of O. viverrini and H. taichui and confirms the extended distribution of O. viverrini in Northern Thailand.

Prevalence and risk factors for pinworm infection in the kindergarten of Thammasat University, Thailand.

We studied the prevalence and risk factors for pinworm infection in children attending the kindergarten of Thammasat University, Pathum Thani, Thailand, using the Scotch-tape technique. Slides were examined by a standard light microscope; 20% of negative slides were reexamined for quality control. Symptoms and risk factor data were collected using a structured questionnaire. Three hundred thirty children age 3 to 6 years old were sampled (males=159). Sixty-five (19.7%) had symptoms consistent with pinworm infection. No pinworm eggs were detected. Most parents (73%) had a good socioeconomic status and 64% were university graduates. Pinworm infection may be uncommon in urban Thailand.

Prevalence of Haplorchis taichui and Haplorchoides sp. metacercariae in freshwater fish from water reservoirs, Chiang Mai, Thailand.

A parasitological investigation on trematode metacercariae was made on 62 freshwater fishes of 13 species in northern Thailand; Cyclocheilichthys apogon, Puntioplites proctozysron, Labiobarbus siamensis, Barbodes gonionotus, Barbodes altus, Henicorhynchus siamensis, Osteochilus hasselti, Notopterus notopterus, Mystacoleucus marginatus, Anabas testudineus, Systomus orphoides, Morulius chrysophykadian, and Hampala macrolepidota. The fish were caught over the summer period (February-May 2007) from 2 Chiang Mai water reservoirs, i.e., the Mae Ngad (UTM 47Q E 503200, 47Q N 2119300) and the Mae Kuang Udomtara (UTM 47Q E 513000, 47Q N 2092600) Reservoirs in Chiang Mai province, Thailand. The prevalence of heterophyid (Haplorchis taichui and Haplorchoides sp.) metacercariae in these fish was 83.9% and 74.2% in the Mae Ngad and Mae Kuang Udomtara Reservoirs, respectively. The highest intensity of heterophyid metacercariae in H. siamensis in the Mae Ngad was 120.4 and that in P. proctozysron in the Mae Kuang Udomtara was 180.0. The fish, A. testudineus, C. apogon, and M. chrysophykadian, were not found to be infected with H. taichui metacercariae. The results show that the freshwater fish in Chiang Mai water reservoirs are heavily infected with H. taichui and Haplorchoides sp. metacercariae.

Human intestinal capillariasis in Thailand.

Intestinal capillariasis caused by Capillaria philippinensis appeared first in the Philippines and subsequently in Thailand, Japan, Iran, Egypt and Taiwan; major outbreaks have occurred in the Philippines and Thailand. This article reviews the epidemiology, history and sources of C. philippinensis infection in Thailand. The annual epidemiological surveillance reports indicated that 82 accumulated cases of intestinal capillariasis were found in Thailand from 1994-2006. That made Thailand a Capillaria-prevalent area. Sisaket, in northeast Thailand, was the first province which has reported intestinal capillariasis. Moreover, Buri Ram presented a high prevalence of intestinal capillariasis, totaling 24 cases from 1994-2006. About half of all cases have consumed raw or undercooked fish. However, even if the numbers of the intestinal capillariasis cases in Thailand is reduced, C. philippinensis infection cases are still reported. The improvement of personal hygiene, specifically avoiding consumption of undercooked fish and promoting a health education campaign are required. These strategies may minimize or eliminate C. philippinensis infection in Thailand.

A study of ectoparasites of Canis lupus familiaris in Mueang district, Khon Kaen, Thailand.

We studied ectoparasites found on Canis lupus familiaris sampled in five areas in Mueang district, Khon Kaen Province, Thailand. The prevalence of fleas and ticks as well as their density were determined in 100 dogs that did not receive treatments. A total number of 458 ectoparasites was found corresponding to two species: 25.8% Ctenocephalides canis and 74.2% Rhipicephalus sanguineus. R. sanguineus was the most abundant species, and Ct. canis was the only flea species found. The stages of R. sanguineus were larvae (5.3%), nymphs (29.1%) and adults (39.1% in male and 26.5% in female). The stages of Ct. canis were larvae (41.5%) and adults (58.5%). Both species were commonly found on domestic dogs in all areas of the study. Ct. canis was not present on domestic dogs in one sub-district. The prevalence rates of tick-harboring domestic dogs was 80% (R. sanguineus), and flea-haboring domestic dogs was 26% (Ct. canis).

Malaria and enterobiasis among Karen Long-neck tribe in Mae Hong Son Province.

In Thailand, Mae Hong Son Province is highly endemic for malaria. Knowing this, the local Health Department has introduced a program to educate local residents about the risk factors, in particular the dangers and symptoms of malaria. This study was conducted to evaluate these efforts, by determining the number of malaria infections in a segment of the population, and also by testing for enterobiasis among a group of its children. Two villages in Mae Hong Son Province were chosen for this purpose with a combined population of about 300. Of these, 195 were screened for malaria. Two subjects were diagnosed positive for malaria by microscopy. One of these two villages was chosen to screen for Enterobius vermicularis infection in children as well. Out of 69 stool samples, five (7%) showed infection with E. vermicularis: three with a low number of eggs (1-50), and two with a high number of eggs (>100). Compared with infection rates in similar studies, the results of this study indicate that the Health Department's efforts are meeting with relative success. The low prevalence of infection indicates that the villagers are using the information they have received to help combat infection.

Parasitic infections among Karen in Kanchanaburi Province, western Thailand.

The purpose of this study was to determine the rate of intestinal parasitic and malarial infections during a period of low infection among the residents of remote Karen villages in Thailand. Fifty-five males and 64 females, aged 6 months to 70 years, were examined for malaria by thick blood smears using the Giemsa staining technique. Of the 119 subjects, 4 (3.36%) showed positive for malaria with vivax gametocytes. Results suggested that mass screening was not an effective way for diagnosing malaria. Stool samples were examined under a light microscope. The overall intestinal parasitic infection rates were 38.24% in 34 males, and 36.11% in 36 females. These were hookworm (17.14%), Ascaris lumbricoides (7.14%), Trichuris trichiura (1.43%), Strongyloides stercoralis (7.14%), Taenia spp (1.43%), Entamoeba histolytica (1.43%), Entamaeba coli (10.00%) and Giatdia lamblia (1.43%). The highest (55.55%) and lowest (16.66%) rates of infection were observed in age groups 0-5 and over 45, years respectively. In addition, A. lumbricoides and T. trichiura were found more frequently in children, while hookworms was found similarly in every age group. Results showed that the Karen living along the western border of Thailand possessed high rates of intestinal parasitic infections. Strict monitoring and control programs for these parasites should be implemented.