Clinical performance of rapid antigen tests in comparison to RT-PCR for SARS-COV-2 diagnosis in Omicron variant: A systematic review and meta-analysis.

The Omicron variant of concern has a high level of mutations in different genes that has raised awareness about the performance of immunological products such as vaccines and antigen detection kits. In this systematic review and meta-analysis, we investigated whether Omicron had a significant influence on rapid antigen test (RAT) performance in comparison to PCR. We registered this systematic review and meta-analysis in PROSPERO with the registration number CRD42022355510. We searched PubMed, Scopus, Embase, and Web of Science databases systematically to 1 August 2022. After article screening, we assessed the quality of the included studies based on the JBI checklist. Following data extraction, we performed a meta-analysis using R software. We included 18 qualified articles presenting sufficient data about RATs performance in comparison to RT-PCR in Omicron infections. The pooled specificity and sensitivity of RATs were 1.000 (0.997-1.000) and 0.671 (0.595-0.721), respectively. The FDA-approved kits showed a better performance than WHO-approved ones with a sensitivity of 0.728 (0.620-0.815). The use of RATs with nasal swabs showed a higher sensitivity compared with nasopharyngeal swabs. The sensitivity for samples with a CT-value >25 was 0.108 (0.048-0.227). Rapid antigen tests show impaired performance for COVID-19 diagnosis when the Omicron variant is circulating, particularly in samples with low viral loads.

Identification of ectoparasites of camels in Sabzevar City, Iran.

Ectoparasite infestation can transmit pathogens. They also cause economic losses and sometimes can cause mortality and reduce growth rates. Therefore, the objective of the present study was the determination of ectoparasite infestations on camels (C. dromedarius) in Sabzevar city, Iran. This survey was conducted from April 2017 to March 2018. A total of 75 camels were examined for ectoparasite infestation. All ectoparasites were collected in vials containing ethyl alcohol (70%) and were brought to the laboratory. The results showed that 25 camels (33.33%) were infested with hard ticks. There was not any infestation by other external parasites (mite, lice, flea, myias). The whole detected ticks were 130. The hard ticks on camels were identified as follows: Hyalomma anatolicum anatolicum (37/69%), Hyalomma dromedarii (34/61%), Rhipicephalus bursa (27/69%), In conclusion, appropriate tick control programs in Sabzevar city would seem a prerequisite for progressing camel milk and meat production.

Prevalence of hydatid cyst, Fasciola spp. and Dicrocoelium dendriticum in cattle and sheep slaughtered in Sabzevar abattoir, Iran.

Hydatid cyst, Dicrocoelium dendriticum, and Fasciola spp. are common parasites among ruminants. The current study was conducted to assess the prevalence of these parasites in cattle and sheep slaughtered in Sabzevar abattoir, from April 2014 to March 2016. Total of 1653 cattle and 26720 sheep were inspected for helminthic infections of liver and lung in different seasons. The prevalence rates were found to be 684 (2.55%) and 235 (14.21%) in sheep and cattle, respectively. The infection rate of liver in cattle was estimated to be 5.86%, 0.84% and 5.68% for hydatid cysts, Fasciola spp. and D. dendriticum, respectively and lung infection with hydatid cyst in cattle was 1.81%. Moreover, the liver infection rate of sheep was estimated to be 0.87%, 0.06% and 2.13% with hydatid cysts, Fasciola spp. and D. dendriticum, respectively and lung infection with hydatid cyst was 0.35%. The rate of infection with D. dendriticum was higher in the both animals than the other parasites. The results of this study indicated that the prevalence of the aforementioned parasites was high, which caused high economic losses. Therefore, sanitary and preventive measures should be taken.