Objective:To understand the status of intestinal helminth infections in Lunan area of Shandong Province (Jining City, Rizhao City, Linyi City, Heze City, and Zaozhuang City), and provide scientific basis for formulating parasitic disease prevention and control strategies.Methods:From 2016 to 2023, a stratified sampling method was used to conduct surveillance in 33 counties (cities, districts, hereinafter referred to as counties) in Lunan area of Shandong Province. Each county was divided into five areas (east, south, west, north, and center), with one administrative village (community) selected from each area. And ≥200 permanent residents (aged ≥3 years old, having lived locally for ≥6 months) were sampled from each village (community), and one stool sample was collected from each participant. The Kato-Katz method (two slides per sample) was used for parasite detection, and the results were analyzed.Results:From 2016 to 2023, a total of 49 436 people were surveyed, including 23 861 males and 25 575 females, with an age range of 3 - 105 years old. The testing identified 687 intestinal helminth infections, with an overall infection rate of 1.39%. The predominant infection was whipworm (582 cases), with an infection rate of 1.18%; followed by roundworm and hookworm, with infection rates of 0.13% (62 cases) and 0.05% (23 cases) respectively; other types of helminths ( Clonorchis sinensis and pinworm) totaled 20 cases, with an infection rate of 0.04%. From 2016 to 2023, the annual intestinal helminth infection rates were 2.76% (201/7 292), 0.90% (56/6 327), 0.84% (52/6 200), 1.70% (124/7 282), 1.23% (88/7 133), 1.45% (104/7 150), 0.34% (17/5 058), and 1.46% (45/3 084), showing an overall downward trend (χ 2trend = 42.40, P < 0.001). The ≥60 age group had the highest intestinal helminth infection rate (2.39%, 323/13 489), while the 30 - 39 age group had the lowest rate (0.68%, 48/7 016). There was statistically significant difference in infection rates among different age groups (χ 2 = 172.25, P < 0.001). There was no statistically significant difference in infection rates between genders (χ 2 = 0.03, P = 0.862). Farmers had the highest infection rate (1.69%, 560/33 118), with statistically significant differences among different occupational groups (χ 2 = 64.88, P < 0.001). Those with primary school education or below had the highest infection rate (1.82%, 445/24 469), with statistically significant differences among different education levels (χ 2 = 64.93, P < 0.001). Conclusions:In Lunan area of Shandong Province, whipworm is the predominant intestinal helminth infection, with elderly people being the high-risk group. Although the intestinal helminth infection rate in this region remains at a low level, there is still a risk of transmission. Continuous surveillance is needed, along with strengthened prevention and control measures for key populations.

Objective:To understand the status of intestinal helminth infections in Lunan area of Shandong Province (Jining City, Rizhao City, Linyi City, Heze City, and Zaozhuang City), and provide scientific basis for formulating parasitic disease prevention and control strategies.Methods:From 2016 to 2023, a stratified sampling method was used to conduct surveillance in 33 counties (cities, districts, hereinafter referred to as counties) in Lunan area of Shandong Province. Each county was divided into five areas (east, south, west, north, and center), with one administrative village (community) selected from each area. And ≥200 permanent residents (aged ≥3 years old, having lived locally for ≥6 months) were sampled from each village (community), and one stool sample was collected from each participant. The Kato-Katz method (two slides per sample) was used for parasite detection, and the results were analyzed.Results:From 2016 to 2023, a total of 49 436 people were surveyed, including 23 861 males and 25 575 females, with an age range of 3 - 105 years old. The testing identified 687 intestinal helminth infections, with an overall infection rate of 1.39%. The predominant infection was whipworm (582 cases), with an infection rate of 1.18%; followed by roundworm and hookworm, with infection rates of 0.13% (62 cases) and 0.05% (23 cases) respectively; other types of helminths ( Clonorchis sinensis and pinworm) totaled 20 cases, with an infection rate of 0.04%. From 2016 to 2023, the annual intestinal helminth infection rates were 2.76% (201/7 292), 0.90% (56/6 327), 0.84% (52/6 200), 1.70% (124/7 282), 1.23% (88/7 133), 1.45% (104/7 150), 0.34% (17/5 058), and 1.46% (45/3 084), showing an overall downward trend (χ 2trend = 42.40, P < 0.001). The ≥60 age group had the highest intestinal helminth infection rate (2.39%, 323/13 489), while the 30 - 39 age group had the lowest rate (0.68%, 48/7 016). There was statistically significant difference in infection rates among different age groups (χ 2 = 172.25, P < 0.001). There was no statistically significant difference in infection rates between genders (χ 2 = 0.03, P = 0.862). Farmers had the highest infection rate (1.69%, 560/33 118), with statistically significant differences among different occupational groups (χ 2 = 64.88, P < 0.001). Those with primary school education or below had the highest infection rate (1.82%, 445/24 469), with statistically significant differences among different education levels (χ 2 = 64.93, P < 0.001). Conclusions:In Lunan area of Shandong Province, whipworm is the predominant intestinal helminth infection, with elderly people being the high-risk group. Although the intestinal helminth infection rate in this region remains at a low level, there is still a risk of transmission. Continuous surveillance is needed, along with strengthened prevention and control measures for key populations.

Objective To investigate the prevalence of Anisakis infections in coastal marine fishes and awareness of anisakiasis control knowledge among local residents in Yantai City, Shandong Province in 2021, so as to provide insights into formulation of anisakiasis control interventions. Methods Marine fishes were purchased from Shunxin Port, Yantai City, Shandong Province in November 2021, and the presence of Anisakis was detected in different species of fishes and different fish sites. The correlations between body length and weight of marine fish and intensity of Anisakis infections were examined using Spearman’s rank correlation analysis, and the dietary habits and anisakiasis control knowledge were investigated using questionnaire surveys among local residents. Results A total of 201 marine fishes belonging to 20 species were dissected, and Anisakis was detected in 77 marine fishes (38.31%) belonging to 11 species (55.00%), with a mean infection intensity of 45.04 parasites per fish (3 468/77). Spearman’s rank correlation analysis revealed that the body length (r_s = 0.74, P < 0.05) and weight (r_s = 0.79, P < 0.01) of the monkfish correlated positively with the intensity of Anisakis infections, and the body length (r_s = 0.68, P < 0.05) of the flatfish correlated positively with the intensity of Anisakis infections, while no correlations were examined between the body length or weight of other marine fishes and the intensity of Anisakis infections. Of all respondents, 53.38% men and 56.67% women did not know anisakiasis control knowledge at all, and there was a significant difference in the proportion of respondents using separate chopping boards for raw and cooked food from different villages (χ² = 17.89, P < 0.01), while there was an age-specific proportion of respondents with habitats of eating raw or semi-raw seafood (χ² = 28.27, P < 0.01). Conclusions The prevalence and intensity of Anisakis infections were high in coastal marine fishes in Yantai City in 2021, and the awareness of anisakiasis control knowledge was low among local residents. Intensified health education pertaining to anisakiasis control knowledge is recommended to reduce the risk of Anisakis infections.