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Background: Amoebiasis, the cause of dysentery and extra-intestinal abscesses, now becomes second fatal parasitic disease in the world. As routine microscopic diagnosis cannot differentiate causative Entamoeba histolytica from non-pathogenic E. dispar and E. moshkovskii , better diagnosis has to be searched., Materials and Methods: Multiplex single round PCR was tested and compared with results of microscopy of wet preparation on 30 samples of diarrheic stools and extra intestinal lesions from amoebiasis suspected patients., Results: Microscopy examination showed that 21 (70%) of the samples were positive for E. histolytica/E. dispar/E. moshkovskii complex and 18 (86%) of them contained hematophagous trophozoites. Multiplex single round PCR showed 12 positive results, from which seven were positive for E. histolytica , two were positive for E. moshkovskii , and three showed mixed of E. histolytica and E. moshkovskii . No samples were positive for E. dispar . High positive rate of microscopy might be related with highly suspected amoebiasis cases, while lower positive PCR might be caused by low parasite density and time-related trophozoite disintegration., Conclusion: The study showed that multiplex single-round PCR is a valuable diagnostic tool for species differentiation, but cannot replace microscopy in the diagnosis of amoebiasis because of its low sensitivity and impossibility to discriminate the form of E. histolytica and whether it is in the disease-causing stage, while microscopic examination is capable to demonstrate the presence of hematophagous trophozoites that indicates it is invasive and at the disease-causing stage of E. histolytica ., Competing Interests: Conflict of Interest: The authors of this manuscript declare that there is no conflict of interest with this study.

Background: Sulawesi in Indonesia has a unique geographical profile with assumed separation from Sundaland. Studies of Helicobacter pylori in this region are rare due to the region's rural location and lack of endoscopy equipment. Indirect methods are, therefore, the most appropriate for measuring H. pylori infection in these areas; with the disposable gastric brush test, we can obtain gastric juice as well as small gastric tissue samples for H. pylori culture. We investigated the prevalence of H. pylori infection and evaluated human migration patterns in the remote areas of North Sulawesi., Methods: We recruited a total of 251 consecutive adult volunteers and 131 elementary school children. H. pylori infection was determined by urine antibody test. A gastric brush test was used to culture H. pylori. We used next-generation and polymerase chain reaction based sequencing to determine virulence factors and multi-locus sequence typing (MLST)., Results: The overall H. pylori prevalence was only 14.3% for adults and 3.8% for children, and 13.6% and 16.7% in Minahasanese and Mongondownese participants, respectively. We isolated a single H. pylori strain, termed -Manado-1. Manado-1 was East Asian type cagA (ABD type), vacA s1c-m1b, iceA1 positive/iceA2 negative, jhp0562-positive/β-(1,3) galT-negative, oipA "on", and dupA-negative. Phylogenetic analyses showed the strain to be hspMaori type, a major type observed in native Taiwanese and Maori tribes., Conclusions: Our data support that very low H. pylori infection prevalence in Indonesia. Identification of hspMaori type H. pylori in North Sulawesi may support the hypothesis that North Sulawesi people migrated from north.

Wild isolates of malaria parasites were preserved in wet ice for 2-12 days and cultivated by a candle jar method. In four isolates of Plasmodium falciparum collected from Myanmar and preserved for 12 days, all failed to grow. In 31 isolates preserved for 5-10 days, nine were transformed to young gametocytes, but 22 isolates grew well. From Ranong, Thailand, nine isolates preserved for 7 days were examined, and six grew well. On the other hand, all of the 59 isolates collected from eastern Indonesian islands failed to establish as culture-adapted isolates, even most of them were preserved only for 2-3 days: 10 isolates stopped to grow, and 49 isolates were transformed to sexual stages by Day 10. These results indicated that a great difference in adaptation to in vitro culture may exist between wild isolates distributed in continental Southeast Asia and in eastern Indonesia and that gametocytogenesis might be easily switched on in Indonesian isolates. In wild isolates of P. vivax, P. malariae and P. ovale preserved for 2-9 days, ring forms or young trophozoites survived, but adaptation to in vitro culture failed. These results indicate that wild isolates can be preserved in wet ice for 9-10 days.

We conducted a field survey of glucose-6-phosphate dehydrogenese (G6PD) deficiency in the eastern Indonesian islands, and analyzed G6PD variants molecularly. The incidence of G6PD deficiency in 5 ethnic groups (Manggarai, Bajawa, Nage-Keo, Larantuka, and Palue) on the Flores and Palue Islands was lower than that of another native group, Sikka, or a nonnative group, Riung. Molecular analysis of G6PD variants indicated that 19 cases in Sikka had a frequency distribution of G6PD variants similar to those in our previous studies, while 8 cases in Riung had a different frequency distribution of G6PD variants. On the other hand, from field surveys in another 8 ethnic groups (Timorese, Sumbanese, Savunese, Kendari, Buton, Muna, Minahasa, and Sangirese) on the islands of West Timor, Sumba, Sulawesi, Muna and Bangka, a total of 49 deficient cases were detected. Thirty-nine of these 49 cases had G6PD Vanua Lava (383T＞C) of Melanesian origin. In our previous studies, many cases of G6PD Vanua Lava were found on other eastern Indonesian islands. Taken together, these findings may indicate that G6PD Vanua Lava is the most common variant in eastern Indonesian populations, except for Sikka.

We conducted field surveys for malaria and glucose-6-phosphate dehydrogenase (G6PD) deficiency in the eastern part of Flores Island, East Nusa Tenggara Province, Indonesia. A total of 1,108 volunteers (642 males and 466 females) belonging to three ethnic groups (Sikka, Ende and Bajo) were examined, and 55 G6PD-deficient individuals (38 males and 17 females) were detected. Among them, 50 samples were analyzed molecularly, in addition to three deficient cases in a Bajo family. In the Sikka population, G6PD Kaiping (1388G>A), one of the two common variants in the Chinese population, was unexpectedly found as the most dominant variant (11/22, 50.0%), followed by G6PD Chatham (1003G>A, 36.4%), G6PD Coimbra (592C>T, 9.1%) and G6PD Vanua Lava (383T>C, 4.5%). Frequency of G6PD Kaiping in the Sikka might be the highest among non-Chinese populations reported so far. In the Ende population, G6PD Vanua Lava (9/14, 64.3%) was the highest, followed by G6PD Kaiping (14.3%), G6PD Chinese-5 (1024C>T, 14.3%) and G6PD Chatham (7.1%). In the Bajo population, a total of 18 deficient cases were analyzed, and a novel mutation (844G>T) in exon 8 with a predicted amino acid change of 282 Asp>Tyr was found in a 7-year-old boy at a Bajo village near Maumere. This new Class II (mild type) variant was also confirmed in his mother and sister, and designated as G6PD Bajo Maumere. The missense mutation at the same nucleotide 844 has been known as G6PD Seattle/Lodi/Modena/Ferrara II, but this mutation is caused by a G>C substitution (282 Asp>His). In the Bajo population, G6PD Viangchan (871G>A, IVS 11 nt93 T>C, 1311C>T), the most common variant in continental Southeast Asian populations, was found to be the dominant (11/18, 61.1%), followed by G6PD Vanua Lava and the new variant (each 16.7%), and G6PD Coimbra (5.6%). These results strongly suggest that the Bajo peoples may have different ancestors from those for Sikka and Ende, and may be much closer to continental Southeast Asian populations. It is interesting that G6PD Canton (1376G>T), another common variant in Chinese, was not seen in the Flores population.

We conducted a survey for malaria diagnosis and treatment in four primary schools in Flores Island, one of the Indonesian Islands with an area of 17000 km(2) and a population of 1.8 million. Of those examined, 24.4% were diagnosed as having malaria (90/363) and administered medicine immediately. A glucose-6-phosphate dehydrogenase (G6PD) test was performed at the same time, and 16 persons (4.4%) were diagnosed as G6PD deficient. Eleven persons consented to analysis of the G6PD genome. We analyzed these subjects and found one case of G6PD Vanua Lava (383T>C), five cases of G6PD Coimbra (592C>T), one case of G6PD Viangchan (871G>A), one case of G6PD Chatham (1003G>A), and three cases of G6PD Kaiping (1388G>A). These were unexpected findings because five different G6PD variants were found in such a small population. This suggests that people of Flores Island are derived from various ancestries.