Vietnam is recognized to be endemic for fasciolosis. However, most of the available publications have not been published in international journals. This review is based on national and international Vietnamese publications and highlights the current status of fasciolosis in Vietnam. It also provides some information available for neighbouring countries. Updated data on responsible species, distribution, transmission and control aspects are summarized. The central region of Vietnam is reported as being highly endemic for fasciolosis, with a high number of human patients (more than 20,000 in 2011). Fasciola gigantica is reported to be the main species in Vietnam. However, hybrids between F. gigantica and F. hepatica were identified. Both humans and animals are infected by the ingestion of raw vegetables and possibly contaminated drinking water. Three lymnaeid snail species (Austropeplea viridis, Radix auricularia and Radix rubiginosa) may act as intermediate hosts of Fasciola spp. However, due to the likely misidentification of snail species and cercariae during the past decade the critical analysis of published data is difficult. A better understanding of transmission aspects of fasciolosis would allow the implementation of preventive measures of this important neglected zoonotic disease.

Paragonimus westermani is one of the most medically important lung flukes and is widely distributed in Asia. It exhibits considerable variation in morphological, genetic and biological features. In central provinces of Vietnam, a high prevalence of metacercariae of this species has been reported from the crab intermediate host, Vietopotamon aluoiense. In this study, we detected P. westermani metacercariae in two additional crab hosts, Donopotamon haii in Quang Tri Province, central Vietnam and Indochinamon tannanti in Yen Bai Province in the north. The latter is a new locality for P. westermani in a northern region of Vietnam where P. heterotremus is the only species currently known to cause human paragonimiasis. Paragonimus westermani metacercariae found in Vietnam showed considerable morphological variation but slight genetic variation based on DNA sequences from the nuclear ribosomal ITS2 region and the mitochondrial 16S gene. Co-infection of the same individual crabs with P. westermani and P. heterotremus and/or some other Paragonimus species was found frequently, suggesting potential for co-infection in humans. The findings of the present study emphasize the need for highly specific molecular and immunodiagnostic methods to differentially diagnose between P. westermani and P. heterotremus infections.

In this study, Mn-doped ZnSe/ZnS core/shell quantum dots (CSQDs) were synthesized in aqueous solution using polyethylene glycol as a surface stabilizer and successfully applied in the detection of Escherichia coli O157:H7 and methicillin-resistant Staphylococcus aureus (MRSA) for the first time. The CSQDs were conjugated with anti-E. coli antibody and anti-MRSA antibody via protein A supported by 1-ethyl-3-(-3-dimethylaminopropyl)carbodiimide hydrochloride for fluorescent labeling of the intact bacterial cells. The detection was performed for the bacterial strains cultivated in Luria-Bertani liquid medium. The obtained results indicate that E. coli O157:H7 and MRSA can be detected within 30 min at a high sensitivity of 101 CFU/mL. This labeling method based on the highly fluorescent CSQDs may have great potential for use in the food industry to check and prevent outbreaks of foodborne illness.

Herein, the effect of three types of capping polymers, mercaptopropionic acid (MPA), polyethylene glycol (PEG), and starch on the photoluminescence of Mn(2+)-doped ZnSe (ZnSe:Mn) nanoparticles, has been investigated. ZnSe:Mn nanoparticles were successfully prepared with a green method of precipitation in aqueous solutions containing MPA, PEG, or starch as stabilizers. The X-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy had proved the formation of ZnSe:Mn particles and the interaction between them and the capping agents. The resultant nanoparticles with different capping polymers were identical in optical property; however, photoluminescence quantum yields (PLQY) as well as the photoluminescence lifetime varied by capping agents. Starch-capped ZnSe:Mn nanoparticles had the biggest size compared to others, which was confirmed using transmission electron microscopy, dynamic light scattering, UV-Vis absorbance and Raman spectroscopy. Also, the PL intensity was significantly enhanced with starch-capped ZnSe:Mn nanoparticles. The PLQYs of starch archived 26%, which was 1.23 or 1.8 times lower than that of ZnSe:Mn nanoparticles capping with MPA or PEG, respectively. Furthermore, the highest decline of PL intensity was detected in PEG, which completely diminished in the 19th week, while both MPA and starch endowed ZnSe:Mn nanoparticles with outstanding PL lifetimes diminished over seven weeks.