Association between Epstein-Barr virus infection and gastric cancer: a systematic review and meta-analysis.

BACKGROUND: Numerous studies conducted over the past 30 years have pointed to the presence of Epstein-Barr virus (EBV) in gastric cancer samples. This study was aimed to provide a meta-analytic review of the prevalence of EBV in gastric cancer patients, and to clarify the relationship between EBV infection and gastric cancer. METHODS: A literature search was performed electronically using online databases for English language publications until July 1, 2019. The pooled EBV prevalence and 95% confidence intervals (CIs) were estimated using a random-effects model. To determine the association between EBV and gastric cancer, pooled odds ratio (OR) and its 95% CI were computed for case-control studies. Two separate analyses were performed on data from case-control studies with matched and non-match pairs designs to calculate the pooled estimates of ORs. RESULTS: The pooled prevalence of EBV in 20,361 gastric cancer patients was 8.77% (95% CI: 7.73-9.92%; I2 = 83.2%). There were 20 studies with matched pairs design, including tumor and tumor-adjacent normal tissue pairs from 4116 gastric cancer patients. The pooled ORs were 18.56 (95% CI: 15.68-21.97; I2 = 55.4%) for studies with matched pairs design and 3.31 (95% CI: 0.95-11.54; I2 = 55.0%) for studies with non-matched pairs design. The proportion of EBV-associated gastric cancer among male cases was significantly higher than among female cases (10.83%, vs. 5.72%) (P < 0.0001). However, the pooled OR estimate for EBV-associated gastric cancer was significantly higher among females (21.47; 95% CI: 15.55-29.63; I2 = 0%) than in males (14.07; 95% CI: 10.46-18.93; I2 = 49.0%) (P = 0.06). EBV was more prevalent in the cardia (12.47%) and the body (11.68%) compared to the antrum (6.29%) (P = 0.0002). CONCLUSIONS: EBV infection is associated with more than 18 times increase the risk of gastric cancer. Although the prevalence of EBV was higher in male patients than in female patients with gastric cancer, women are more likely than men to develop EBV-associated gastric cancer. Our findings showed that using tumor-adjacent normal tissues as the control group provides more robust and accurate results regarding the relationship between EBV infection and gastric cancer.

Intestinal parasites among migrant barn swallows (Hirundo rustica) in the central region of Mazandaran Province, Northern Iran.

AIM: Swallows are a family of migratory birds found worldwide except Antarctica. Annually, a number of species of swallows migrate to Iran. As they make their nests close to human living places, this may be a potential risk for public health. Conversely, no study has been conducted on intestinal parasitic infections of these birds so far. Therefore, the objective of this study was to determine the prevalence of intestinal parasites in migratory swallows (Hirundo rustica) in the central region of Mazandaran Province, Northern Iran. MATERIALS AND METHODS: In this cross-sectional study, 205 feces samples from two districts (Sari and Qaemshahr) in the central region of Mazandaran were randomly collected during the summer and spring sessions of 2016-2017. The collected samples were examined using the routine direct fecal examination and formalin-ethyl acetate concentration. In addition, the samples were examined by cold acid-fast staining method to detect possible Cryptosporidium oocysts. RESULTS: The results of this study indicated that 38 samples (18.5%) were infected with intestinal parasites. Among the helminthic parasites, eight genera and species were identified as follows: Ascaridia galli, Syngamus trachea, Raillietina, Toxocara spp., Choanotaenia, Taenia spp., Ascaridia spp., and Moniezia spp. In addition, among protozoan parasites, only the Coccidia spp. oocysts were identified. CONCLUSION: Our findings showed a relatively high prevalence of parasitic infections in migratory barn swallows in Mazandaran Province. Given the presence of zoonotic parasites in the samples, further investigations are needed to identify all parasites fauna, particularly zoonotic species among swallows in the region.

Epidemiological aspects of cystic echinococcosis in slaughtered herbivores in Sari abattoir, North of Iran.

A study was conducted to assess the ruminants' hydatidosis in Mazandaran Province, Northern Iran. A total, 1,799 sheep, 985 goats and 362 cattle slaughtered at Sari industrial slaughter house were examined for hydatid cyst infection. The results indicated that 65.2% of sheep, 37.8% of goats and 40.1% of cattle were infected. The liver and lung infection rate in sheep were 18.8 and 4.3%, goats 17.2 and 12.6% and cattle 44.1 and 7.6%, respectively. The study showed that 766 (45.3%) out of 1,691 infected animals had moderate degree of infection. Geographical zone survey indicated that 1,381 (89.2%) out of 1,546 sheep and goats infected with hydatid cyst were non-indigenous and originated from north-eastern provinces of Iran. On the contrary, 50.3% of infected cattle originated from Mazandaran Province (indigenous).