Molecular and immunological analyses of confirmed Plasmodium vivax relapse episodes.

Background: Relapse infections resulting from the activation hypnozoites produced by Plasmodium vivax and Plasmodium ovale represent an important obstacle to the successful control of these species. A single licensed drug, primaquine is available to eliminate these liver dormant forms. To date, investigations of vivax relapse infections have been few in number.

Leptospira species in floodwater during the 2011 floods in the Bangkok Metropolitan Region, Thailand.

Floodwater samples (N = 110) collected during the 2011 Bangkok floods were tested for Leptospira using culture and polymerase chain reaction (PCR); 65 samples were PCR-positive for putatively non-pathogenic Leptospira species, 1 sample contained a putatively pathogenic Leptospira, and 6 samples contained Leptospira clustering phylogenetically with the intermediate group. The low prevalence of pathogenic and intermediate Leptospira in floodwater was consistent with the low number of human leptospirosis cases reported to the Bureau of Epidemiology in Thailand. This study provides baseline information on environmental Leptospira in Bangkok together with a set of laboratory tests that could be readily deployed in the event of future flooding.

A single injection of 19 kda carboxy-terminal fragment of Plasmodium yoelii merozoite surface protein 1 (PyMSP1(19)) formulated with Montanide ISA and CpG ODN induces protective immune response in mice.

Objective: To investigate the efficacy of a vaccine formulation of the 19 kDa conserved carboxyl-terminal fragment of Plasmodium yoelii merozoite surface protein-1 (PyMSP1(19)) formulated with CpG ODN 1826 and Montanide ISA51 or ISA720 when used to immunize mice by a single injection.

Methods: Groups of BALB/c mice were immunized parenterally with one, two or four injections with PBS or PyMSP1(19) formulated with CpG ODN in ISA51 or ISA720. Sera were collected weekly and assessed for total IgG and IgG subclass titers.

Detection of Salmonella invA gene in shrimp enrichment culture by polymerase chain reaction.

Contamination of seafood with salmonellae is a major public health concern. Detection of Salmonella by standard culture methods is time consuming. In this study, an enrichment culture step prior to polymerase chain reaction (PCR) was applied to detect 284 bp fragment of Salmonella invA in comparison with the conventional culture method in 100 shrimp samples collected from four different shrimp farms and fresh food markets around Bangkok.

Haplotypes of IL12B promoter polymorphisms condition susceptibility to severe malaria and functional changes in cytokine levels in Thai adults.

Polymorphic variability in immune response genes, such as IL12B, encoding the IL-12p40 subunit is associated with susceptibility to severe malaria in African populations. Since the role of genetic variation in conditioning severe malaria in Thai adults is largely unexplored, the functional association between IL12B polymorphisms [i.e.