Eggs appear in the feces first between 9–11 weeks post-infection. The cause of this is unknown, and it is also difficult to distinguish between the different species of fasciola as well distinguishing them from echinostomes and Fasciolopsis. Most immunodiagnostic tests detect infection with very high sensitivity, and as concentration drops after treatment, it is a very good diagnostic method. Clinically it is not possible to differentiate from other liver and bile diseases. Radiological methods can detect lesions in both acute and chronic infection, while laparotomy will detect lesions and also occasionally eggs and live worms.Because of the size of the parasite, as adult F. hepatica: 20–30 × 13 mm (0.79–1.18 × 0.51 inches) or adult F. gigantica: 25–75 × 12 mm (0.98–2.95 × 0.47 inches), fasciolosis is a big concern. The amount of symptoms depend on how many worms and what stage the infection is in. The death rate is significant in both cattle (67.55%) and goats (24.61%), but generally low among humans. Treatment with triclabendazole has been highly effective against the adult worms as well as various developing stages. Praziquantel is not effective, and older drugs such as bithionol are moderately effective but also cause more side effects. Secondary bacterial infection causing cholangitis  has also been a concern and can be treated with antibiotics, and toxaemia may be treated with prednisolone.Humans are infected by eating watergrown plants, primarily wild-grown watercress in Europe or morning glory in Asia.
According to Robert E. Black of the Johns Hopkins School of Public Health (JHSPH), "Underweight status ... and micronutrient deficiencies also cause decreases in immune and non-immune host defenses, and should be classified as underlying causes of death if followed by infectious diseases that are the terminal associated causes." People who are malnourished raise special concerns, as not only gross caloric intake may be inadequate, but also intake and absorption of other vital nutrients, especially essential amino acids and micronutrients such as vitamins and minerals.In women, being severely underweight, as a result of an eating disorder or due to excessive strenuous exercise, can result in amenorrhea (absence of menstruation), infertility or complications during pregnancy if gestational weight gain is too low.Malnourishment can also cause anemia and hair loss. Being underweight is an established risk factor for osteoporosis, even for young people. This is seen in individuals suffering from relative energy deficiency in sport, formerly known as female athlete triad: when disordered eating or excessive exercise cause amenorrhea, hormone changes during ovulation leads to loss of bone mineral density. After this low bone mineral density causes the first spontaneous fractures, the damage is often irreversible. Although being underweight has been reported to increase mortality at rates comparable to that seen in morbidly obese people, the effect is much less drastic when restricted to non-smokers with no history of disease, suggesting that smoking and disease-related weight loss are the leading causes of the observed effect. Treatment
Diet
Underweight individuals may be advised to gain weight by increasing calorie intake.