Fish-borne trematode metacercariae detected in fish commonly used for raw consumption in Ninh Binh Province, Vietnam

@#Raw or undercooked fish dishes are the major sources of human infection of fishborne trematodes (FBT) and the situation of metacercarial infection in fish greatly affect the prevalence in humans, especially those fish that are commonly used for raw consumption. To investigate the situation of infection with metacercaria of FBT in fish often used to prepare raw fish dishes by local people to assess the risk of infection to humans in Ninh Binh province, Vietnam. 345 fish belonging to five species of freshwater and one species of brackish water fish were collected from fishermen or small-scale fish dealers in Kim Son and Yen Khanh districts, Ninh Binh province between May 2017 and May 2018. Metacercaria of FBT was discovered by pepsin and hydrochloric acid digestion techniques and identified by the morphological and molecular analysis. Among examined fish, 44.06% infected with FBT metacercaria and the highest prevalence was in Cyprinus carpio (86.54%), Ctenopharyngodon idellus (78.43%) and Hypophthalmichthys molitrix (66.67%) while Konosirus punctatus – the brackish water fish – were free from infection. Three species of FBT were found; namely Haplorchis pumilio (accounting for 99.84% of collected metacercariae), Haplorchis taichui and Clonorchis sinensis. The average density was 1.06 metacercariae per gram of freshwater fish and the highest number was of C. idellus (6.38 cysts/gram) followed by Cirrhinus molitorella and C. carpio. Results of the study show the high prevalence of infection of FBT metacercariae among freshwater fish often used to prepare raw fish dishes in Ninh Binh province. These findings suggest the need for greater awareness of the risk from raw fish dishes among public health authorities and people.

The situation of malaria along the Vietnam-Lao PDR border and some related factors.

This was a descriptive cross sectional study. It was done in 4 communes along the Vietnam-Lao PDR border of two mountainous provinces: Sonla and Nghean. The cluster multistage sampling technique was applied to choose the study sites. The results of the study show: Among the 2,441 persons given blood tests to find malaria parasites, 0.7% of them carry malaria parasite, of whom 0.6% carry P. falciparum and 0.1% carry P. vivax. The malaria morbidity in the year was 6.9%. The mortality due to malaria is 1.59 per 100,000 population per year. Among the 106 hamlet motivators being interviewed, only 75.5% knew that malaria is transmitted by mosquitos, 71.7% knew that malaria patients are a source of transmission, over 50% of the motivators have mistaken understanding about the living environment of malaria mosquitos. Most of them have had mistakes in diagnosis, treatment of malaria, mosquito-killing spraying. Among the 729 adults being interviewed, 59.0% did not know about the causes of malaria, 30.7% did not take part in malaria control activities. Only 69.3% of the adults regularly sleep inside mosquito nets, 68% of adults buy medicine to cure malaria, 39.9% referred patients to health facilities for cure, and 25% use forest herbs to cure malaria. The factors that increased the malaria morbidity in communes along Vietnam-Lao PDR border have been identified.

Paragonimiasis in Sin Ho District, Lai Chau Province, Viet Nam.

Forty-four cases of pulmonary paragonimiasis, two also with evidence of cerebral infection, were found in Sin Ho District in Northern Viet Nam. There were 30 males and 14 females, 2-30 years of age. The diagnosis was made by sputum examination. Pet dogs and wild dogs in the area were also found infected and the people often eat roasted crabs.