Epidemiology of hydatid disease in Najaf province / Iraq

One hundred and twenty four patients infected with hydatid cyst were clinically and surgically proved . Follow up was done in Al-Sadder Medical City, Najaf / Iraq during January to December 2014 . The incidence of hydatidosis in female was higher than that in males . The youngest was 5 years and the oldest was more than 70 years old . The highest age distribution of hydatidosis patients was between 21 – 30 years . The percentage of liver hydatidosis was higher ( 40.32 % ) than other organs . Patients with large size(> 5 cm) cyst were more than those with small cyst (< 5 cm) .


Gender distribution
The total number of hydatidosis patients included in this study was 124, 97(78.3% females) and 27(21.7% males) (Table 1.) . The result showed that more females were found to be infected than males .

Age distribution
The ages of patients studies were between 5 and more than 70 years . The majority of cases 32(25.8%) which were found to be infected (male and female) at the age groups 21-30 years . The youngest age was 5 years and the oldest was more than 70 years old ( Table 2) .

Size and site of cyst
Only 50 cyst were measured from the total of 124 patients . 23 (46.00 %) had cysts less than 5 cm in diameter, whereas the remaining 27(54.00%) had cysts larger than 5 cm in diameter, ( Table 4) . From a total of 22 liver cyst, 12(70.58%) has less than 5 cm in diameter and 10(45.45%) has more than 5 cm, whereas from a total of 17 lungs cyst, 5(29.41%) had less than 5 cm in diameter, 12(54.54%) had more than 5 cm in size (Table 5) .

Discussion
In this study, there are a marked increase in the incidence of the hydatid disease in Najaf province, this may due to lack appropriate personal hygiene practice to prevent ingestion of the eggs, and the practice of feeding dogs potentially contaminated viscera . Poor educational program for inhabitant in area (at risk) for transmission of parasite (11) . Insufficient meat inspection, poor dog management and in appropriate legislation (12) . No active collaboration between veterinarians and public health workers (13) . Available stray dogs or sheep dogs (14) . All these are responsible for transmission of disease .The gender distribution showed that the predominance of hydatidosis was in females (78.3%) than in males (21.7%) . This has been also observed by (8,16,17), where they found that the infection rate was higher in females than in males . This may be due to the social life in our district where the females are confined to house working and this will make them more exposed to the source of infection especially in rural area .The age range of the cases studies was from 5 years up to 70 years . The highest prevalence with regard to age distribution was between 21-30 years . It was shown that the age range between 11-40 years was the age of highest incidence (18,19), while (8) and (17) showed that the highest rate of infection was between 20-30 years .
The study showed that most of the patients had hydatidosis of the liver, followed by the lungs, kidney, spleen, brain, omentum and leg . This finding is well documented by (2,19) . This is probably because most frequently the oncosphere enters the portal vein in the liver, the first capillary filter . If it passes the liver, it reaches the lung and other distant foci (19,20) .The cysts of E.granulosus never infilterate or invade the tissues of the host and hence exist as a foreign body . In this study a high percentage of our patients had large size cyst (more than 5 cm in diameter) . These large cysts were seen more in the lung than in the liver . The cyst morphological characteristics are largely determined by the resistance offered by the involved organs . In the soft parenchymatous tissues of the lungs, the cysts expand rapidly and may 08 become very large . The firm texture of the liver, on the other hand, exerts a definite restraining influence on the expansion of the cyst, hence, they remain rather small (21) .