Prevalence of parasitic contamination of raw vegetables in Nakhon Si Thammarat province, southern Thailand

Abstract

BackgroundSoil-transmitted helminth (STH) infections are major public health problems in poor and developing countries that require fecal contamination of the environment for transmission. The consumption of raw vegetables without proper washing is one of the main routes of intestinal parasite acquisition. Therefore, this study was designed to detect the prevalence of intestinal parasitic contamination in commonly consumed raw vegetables sold in three central open-air markets in Nakhon Si Thammarat province, southern Thailand.MethodsA total of 265 fresh vegetable samples consisting of peppermint, lettuce, coriander, leek, gotu kola, celery, Chinese cabbage, culantro, Thai basil, and Chinese morning glory were purchased from three central open-air markets in the Mueang, Thasala and Sichon districts from December 2016 to March 2017. Each sample was washed with physiological saline, shaken for 15 min, and then allowed to sediment. Finally, sedimentation was performed via the sedimentation concentration technique and examined using light microscopy for the detection of pathogenic parasites.ResultsThe overall prevalence of parasitic contamination was 35.1% (93/265). The most predominant parasite was hookworms (42.9%), followed by Strongyloides stercoralis (10.6%), Trichuris trichiura (2.6%), Ascaris lumbricoides (2.6%), and Toxocara spp. (2.6%). The highest level of contamination was found in celery, with a prevalence rate of 63.3% (19/30), while the lowest contamination level was found in Chinese morning glory, with a prevalence rate of 2.0% (2/30). The prevalence of intestinal parasite contamination in Mueang district (51.5%) was significantly higher than that in Thasala district (17.9%) and Sichon district (30.6%) (P < 0.001).ConclusionThe results of the present study demonstrate that consumption of vegetables with parasite contamination in this area represents a potential route for the transmission of parasitic infection, particularly hookworm infection. Therefore, it is necessary for health authorities to educate consumers about the proper washing of vegetables prior to consumption. Preventive methods such as wearing gloves and washing hands after handling vegetables should also be advocated to sellers who are at risk of acquiring STH infections via skin penetration.

Seroprevalence of Toxocara canis infection and associated risk factors among primary schoolchildren in rural Southern Thailand

“…This study emphasizes the importance of hand hygiene to prevent parasite eggs from entering the body. Despite the report of Toxocara egg contamination in raw vegetables in Nakhon Si Thammarat Province in a previous study [26], eating fresh vegetables was not significantly associated with T. canis infection in the current study. This may be explained by the small number of schoolchildren who ate fresh vegetables (36, 20.3%); thus, contamination from vegetables was not a likely route of transmission among these children.…”

“…In Thailand, previous reports revealed that Toxocara eggs were found in the stool of dogs and cats [24,25]. Furthermore, Toxocara eggs were identified in raw vegetables from markets in southern Thailand [26]; however, their impact on humans has not been investigated. In this study, we aimed to assess the seroprevalence of Toxocara canis infection and the associated risk factors among schoolchildren in rural areas of southern Thailand.…”

Seroprevalence and associated risk factors of Toxocara canis infection among primary schoolchildren from rural areas of southern Thailand

“…This study emphasizes the importance of hand hygiene to prevent parasite eggs from entering the body. Despite the report of Toxocara egg contamination in raw vegetables in Nakhon Si Thammarat Province in a previous study [22], eating fresh vegetables was not significantly associated with T. canis infection in the current study. This may be explained by the small number of schoolchildren who ate fresh vegetables 36 (20.3%); thus, contamination from vegetables was not a likely route of transmission among these children.…”

“…In Thailand, previous reports revealed that Toxocara eggs were found in the stool of dogs and cats [20,21]. Furthermore, Toxocara eggs were identified in raw vegetables from the markets in southern Thailand [22]; however, its impact on humans has not been investigated. In this study, we aimed to assess the seroprevalence and associated risk factors of Toxocara canis infection among schoolchildren in rural areas of southern Thailand.…”

Egg genotyping reveals the possibility of patent Ancylostoma caninum infection in human intestine

“…It has also to be considered that the potential uptake of animals A. caninum eggs does not necessarily mean that relevant amounts of animals faeces need to be taken up, since eggs may have been attached to food. In fact, many studies report the presence of hookworm eggs in food 43,44 and also in water 45 . However, this a very low probability since twelve A. caninum eggs were found in the respective patient.…”