Taenia solium is a parasite causing porcine cysticercosis and human taeniosis and cysticercosis, parasitic zoonoses with a serious public health and economic influence. It has been globally ranked as the top foodborne parasite by the Food and Agriculture Organisation of the United Nations (FAO) and the World Health Organisation (WHO). This parasite is transmitted mainly in countryside regions where animals are free roaming, having access to human faeces, and infected pork is widely available. More developed countries eliminated cysticercosis; nonetheless, there are insufficient data about the current endemicity status of T. solium, due to increased human migration from endemic areas. Formally submitted statistics on cysticercosis in pigs are extremely inadequate. This is the result of not reporting all cases of the disease by some countries and lack of molecular verification during identification of the parasite. There is a need to develop diagnostic tests with increased sensitivity and specificity. The purpose of the present review is to summarise current knowledge about diagnostic and control methods concerning T. solium infection. The article does not address the diagnostics of human cysticercosis, since there is a distinct medical field which should be discussed separately. The paper focuses mainly on identifying the sources of T. solium infection, presenting the methods to detect and control porcine cysticercosis and taeniosis in humans.

Although ovine cysticercosis is not a zoonotic problem, it results in substantial economic losses due to the condemnation of infected tissues or entire carcasses. This study aimed to record preliminary data on the prevalence, and phylogenetic diversity of Cysticercus ovis isolates from slaughtered sheep in the province of Sulaymaniyah, Iraq. From January to September 2020, 6, 411 slaughtered sheep were examined for C. ovis by routine meat inspection. The amplification and sequence analysis of the COX1 gene for up to 35 specimens of C. ovis was performed using conventional PCR. The overall prevalence rate was 1.3%, and the prevalence was significantly higher in older sheep (>1 year) than younger ones (<1 year) (P< 0.05). The cardiac muscle showed a higher tendency to carry C. ovis infection compared to other examined muscles. Sequence analysis of the COX1 gene revealed six haplotypes, and the level of pairwise nucleotide diversity between individual haplotypes was 1–2%. Five out of six of the Taenia ovis haplotypes recovered could have been recorded for the first time globally. Phylogenetic interpretation indicated that all the T. ovis haplotypes clustered in a single clade, and it also indicated an extremely close similarity to Iranian and New Zealand isolates. Globally, this report adds new data on C. ovis genetic diversity, which provide an extremely useful molecular background with regard to future preventive as well as control strategies.

Cysticercosis caused by the larval stage of Taenia hydatigena is economically the most important endemic parasitic disease in Iraq. Few data are available relating to the genetic divergence of this helminth. This study aimed to molecularly characterise Cysticercus tenuicollis isolates from sheep in Sulaymaniyah province, Iraq. DNA extraction and amplification of specimens of C. tenuicollis from 46 sheep were conducted by PCR for the mitochondrial 12S rRNA gene. The 19 amplicons were subjected to purification and partial sequencing. Five 12S rRNA nucleotide sequence haplotypes were found. The pairwise nucleotide difference between haplotypes of 12S rRNA gene ranged from 0.2% to 0.7%. Four out of the five haplotypes of C. tenuicollis contained one to two base mutations and were discovered in Iraq for the first time, and this may be a unique mutation globally which has not been recorded previously. Three newly recorded haplotypes contained only one single mutation, and the other one contained two mutations. Phylogenetic analysis showed that all isolated strains were closely related to Iranian sheep isolates. Four new strains of T. hydatigena were discovered for the first time in the study area.

Taenia solium is a parasite causing porcine cysticercosis and human taeniosis and cysticercosis, parasitic zoonoses with a serious public health and economic influence. It has been globally ranked as the top foodborne parasite by the Food and Agriculture Organisation of the United Nations (FAO) and the World Health Organisation (WHO). This parasite is transmitted mainly in countryside regions where animals are free roaming, having access to human faeces, and infected pork is widely available. More developed countries eliminated cysticercosis; nonetheless, there are insufficient data about the current endemicity status of T. solium, due to increased human migration from endemic areas. Formally submitted statistics on cysticercosis in pigs are extremely inadequate. This is the result of not reporting all cases of the disease by some countries and lack of molecular verification during identification of the parasite. There is a need to develop diagnostic tests with increased sensitivity and specificity. The purpose of the present review is to summarise current knowledge about diagnostic and control methods concerning T. solium infection. The article does not address the diagnostics of human cysticercosis, since there is a distinct medical field which should be discussed separately. The paper focuses mainly on identifying the sources of T. solium infection, presenting the methods to detect and control porcine cysticercosis and taeniosis in humans.

In rats infected with the cestode Taenia taeniaeformis, hepatomegaly results from development of parasitic cysts in the liver. Diffuse nodular mucosal hyperplasia in the glandular region (corpus and antrum) of the stomach, and gross thickening of the intestinal mucosa also result. Between postinfection days (PID) 21 and 84, radiologic observations were made after oral administration of a barium sulfate suspension in T taeniaeformis-infected rats and in age/sex-matched controls. There was radiographic evidence of hepatic enlargement at PID 21. Enlargement of the gastric folds was first observed along the greater curvature of the stomach at PID 35. Fimbriation of small intestinal mucosal surfaces resulted from thickening of the intestinal villi and was observed in the duodenum at PID 21. Intestinal motility was assessed, and contractions were counted, using image intensification fluoroscopy, then were recorded on videotape. There were no significant differences between control and infected rats for gastric emptying time, intestinal transit time, and number of intestinal contractions per minute. Barium contrast radiography clearly indicated large gastric folds, thickening of the small intestinal villi, and hepatic enlargement, and was useful for assessing gastrointestinal motility.

Meat inspection is the routine method used to identify cattle infected with Taenia saginata; however, the sensitivity of this method is low. We investigated the prevalence of T. saginata infection in cattle slaughtered in low throughput abattoirs (LTs) in Gauteng province, South Africa, based on meat inspection and serology. A total of 188 cattle carcasses from three abattoirs underwent meat inspection for the presence of T. saginata cysticerci, while serum was tested for the occurrence of antigens using antigen enzyme-linked immunosorbent assay (Ag-ELISA). Polymerase chain reaction (PCR)-sequencing was performed to confirm T. saginata cysts identified during enhanced inspection and incision of 10 randomly selected hearts. Apparent and true prevalence were calculated, and a logistic regression model was fit to evaluate associations between abattoir, sex, animal origin, age and T. saginata serological status. Out of the 188 carcasses, no positive cases (0%) were identified during routine meat inspection, yet three cysticerci-like lesions were identified from three hearts following additional incisions, of which one was confirmed as T. saginata. Fifty-four of the sampled cattle carcasses tested positive using Ag-ELISA (apparent and true prevalence: 29.0%, 71.8%). Feedlot cattle were less likely (odds ratios [OR]: 0.33, p = 0.043) to have a positive serological test result for T. saginata compared to non-feedlot cattle, and the odds of a positive result differed between abattoirs (p  0.05). Contribution: Our results confirmed the low sensitivity of routine meat inspection in LTs, which may pose a public health risk, and therefore other diagnostic methods need to be included in the surveillance system for T. saginata.

Poverty, hunger and the need for production of pigs with meagre or zero inputs have made most farmers release their pigs to range freely, thus creating a pig-human cycle that maintains Taenia solium, the pig tapeworm and cause of porcine cysticercosis, in the ecosystem. A preliminary study was designed to establish the prevalence of porcine cysticercosis by postmortem examination of the tongue and carcass of free-range pigs from February to April 2014 in Arapai subcounty, Soroti district, eastern Uganda. The tongue of each pig was extended and examined before deep incisions were made and the cut surfaces were examined. The rest of the carcasses were examined for cysts. Out of 178 pigs examined, 32 were qualitatively positive for porcine cysticercosis, representing a prevalence of 18.0%. This high prevalence represents a marked risk to the communities in the study area of neurocysticercosis, a debilitating parasitic zoonosis. Proper human waste disposal by use of pit latrines, confinement of free-range pigs and treatment with albendazole and oxfendazole are recommended.

Data from slaughter plants (n = 3) and feedlots (n = 18) in eastern Washington were analyzed to characterize occurrence patterns of cysticercosis in Washington during 1984. Three concurrent peaks in cysticercosis rates (0.6/1,000 to 5/1,000 slaughtered cattle) were detected at 3 slaughter plants. Peaks were observed at 8 feedlots from December 1983 to March 1984, at 6 feedlots from April to July 1984, at 2 feedlots from August to October 1984, and at 3 feedlots from November 1984 to February 1985. Affected feedlots were not closely associated geographically and were feeding cattle from many, predominantely northwestern, origins. For 3 feedlots for which time in the feedlot was available for each slaughter shipment, an increase in cysticercosis rate with increasing time in the feedlot was noticed. Within these 3 feedlots, cases of cysticercosis were widely scattered spatially. The pattern of cysticercosis indicated human fecal contamination of a regionally available feed source. Of feedstuffs in use, potato waste, a byproduct of the processed potato industry, appeared to be the most likely source of Taenia saginata ova.

Taenia saginata cysticercosis is one of the zoonotic diseases that threaten food safety and food security, particularly in developing countries. A cross-sectional study was conducted to estimate the prevalence and cyst distribution in infected cattle, and food safety implications of Taenia saginata cysticercosis in Harari People’s National Regional State, eastern Ethiopia. Post-mortem inspection of carcasses and organs of slaughtered cattle in Harar Municipal Abattoir, cyst viability tests and interviews with randomly selected meat consumers were undertaken. The post-mortem inspection showed that of the 898 local zebu cattle slaughtered for human consumption and examined for the presence of cysticerci of T. saginata, 19.7% (177/898; 95% CI = 17.2–22.5) harboured at least one cyst in the muscles or organs inspected. Of the edible anatomical sites with cysticerci, shoulder muscle, liver and heart together represented 65.4%, 66.0% and 65.4% respectively of relative prevalence, total cyst count and cyst viability. These edible sites are preferred above others by local people for preparation and consumption of raw or inadequately cooked meat dishes that are locally served as kurt, kitffo and dullet. The interviews revealed that among the 300 study participants, 182 (60.7%) had been infected by taeniosis at least once during the previous year and of these 99.0% had eaten raw or undercooked beef, the majority (88.3%) obtained from butchers assumed to provide officially inspected meat that was fit for consumption. This indicated that existing meat inspection processes were inadequate to prevent carcasses infected with T. saginata cysticerci from reaching consumers. The high prevalence of viable cysts in the edible parts of beef together with the widespread consumption of raw or undercooked beef indicated the importance of T. saginata cysticercosis as a food safety problem in eastern Ethiopia. The promotion of policies to upgrade existing meat inspection procedures and public education to ensure effective prevention of T. saginata taeniosis in humans were recommended.