Evaluation of the Impact of the COVID-19 Pandemic on Cystic Echinococcosis Indirect Hemagglutination Test Dynamics: A Single-center Experience.

OBJECTIVE: Cystic echinococcosis (CE) is one of the neglected tropical diseases announced by the World Health Organization. In the period entered with the Coronavirus disease-2019 pandemic, the fight against such diseases has become even more difficult. In our study, we aimed to make inferences about the effects of the pandemic on the diagnosis of the disease by evaluating the number and results of CE indirect hemagglutination test (IHA) before and during the pandemic. METHODS: The number of IHA test requests and positivity rates in the 30-month periods before and after March 11, 2020, when the first case was seen in our country, were evaluated retrospectively. Statistical analysis was made with SPSS version 23 (SPSS, Chicago, IL, USA) program. RESULTS: The results of 1444 patients before the pandemic and 870 patients during the pandemic period were examined. The difference between IHA positivity rates, which was found to be 18.49% before the pandemic and 14.6% during the pandemic, was statistically significant (p=0.016). The positivity rates of women and men were found to be statistically similar in both periods (pbefore=0.621, pafter=0.238). The age group with the highest IHA positivity rate was 20-39 in both periods, and the difference between the positivity rates of the age groups was statistically significant (p<0.001). CONCLUSION: A significant decrease was observed in the rate of IHA positivity during the pandemic period. The status of no increase in positivity rates despite a significant decrease in IHA tests makes us think that the diagnosis may be missed in some patients or that there could be disruptions in their follow-up. For this reason, in order to continue the fight successfully against CE, which is an important public health problem for our country, early diagnosis and regular follow-ups should be emphasized with educations, and the laboratory-clinician communication should be strengthened in order to use tests more efficiently.

Seroprevalence and risk factors of Toxoplasma gondii infection in domestic raccoon dogs in four provinces in northern China.

Toxoplasma gondii is an obligate intracellular apicomplexan parasite that can infect almost all homoiothermal animals, including domestic raccoon dogs (Nyctereutes procyonoides). However, related reports on T. gondii infection in domestic raccoon dogs were limited in China. Therefore, a serological investigation was undertaken to investigate the seroprevalence and risk factors for T. gondii infection in domestic raccoon dogs. A total of 962 serum samples were collected from Jilin, Liaoning, Heilongjiang and Hebei provinces, northern China between April 2016 and November 2017, and were detected by the indirect hemagglutination test (IHA). The seroprevalence of T. gondii infection was 7.28% in the overall surveyed raccoon dogs by IHA, which was different among the four provinces ranging from 6.54% to 7.57%. The seroprevalence of T. gondii infection in male and female raccoon dogs was 6.62% and 7.79%, respectively. Based on statistical analysis, age was regarded as an important risk factor for T. gondii infection in raccoon dogs in this study (P < 0.05). This study reported the seroprevalence and risk factors of T. gondii infection in domestic raccoon dogs in northern China, which provided essential data for prevention and control of T. gondii infection in raccoon dogs in Jilin province, Liaoning province, Heilongjiang province and Hebei province.

Serological diagnosis methods of schistosomiasis japonica at different preva-lence:a meta-analysis / 中国血吸虫病防治杂志

Objective To comprehensively evaluate the effects of indirect hemagglutination test(IHA),enzyme?linked im?munosorbent assay(ELISA),and dipstick dye method(DDIA)in the diagnosis of schistosomiasis japonica at different preva?lence by using Meta?analysis. Methods Through the literature review according to the inclusion and exclusion criteria,a data?base was established,and by using Meta?disc and R software,the Meta?analysis was performed including the threshold test,het?erogeneity test,weighted by the quantitative effect of merger,SROC curve fitting,etc. Results A total of 60 papers were in?cluded in the final analysis. The sensitivities of IHA were 0.84,0.76 and 0.94 in heavy,medium and low endemic areas,and specificities were 0.73,0.64 and 0.73 respectively;the sensitivities of ELISA were 0.88,0.80 and 0.93 in heavy,medium and low endemic areas,and the specificities were 0.59,0.59 and 0.62 respectively;the sensitivities of DDIA were 0.93,0.81 and 0.93 in the heavy,medium and low endemic areas,and specificities were 0.66,0.69 and 0.59 respectively. The weighted sensi?tivities of IHA,ELISA and DDIA were 0.83,0.87 and 0.90 respectively;the weighted specificities were 0.69,0.60 and 0.62 re?spectively. The areas under the curve of SROC were 0.89,0.96 and 0.92 in IHA,ELISA and DDIA respectively. Conclusions In different prevalence,the effectiveness of different methods for serological diagnosis of schistosomiasis is different. The sensi?tivity and specificity of all diagnostic methods of schistosomiasis need to further improve.

Efficiency of three methods for detecting Toxoplasma IgG antibody / 中国血吸虫病防治杂志

Objective To discuss the test efficiency of three methods for detecting Toxoplasma IgG antibody. Methods To-tally 304 specimens were detected parallelly for Toxoplasma IgG antibody by using the gold marked method,indirect hemagglutina-tion test(IHA),and enzyme-linked immunosorbent assay(ELISA),and the sensitivity,specificity and Youden index of these methods were compared. Results The detection sensitivities of gold marked method,IHA,and ELISA for Toxoplasma IgG anti-body were 85.5%,89.8%and 91.9%respectively(χ2=4.12,P>0.05);the specificities were 92.4%,96.6%and 97.5%respec-tively(χ2=4.06,P>0.05). The detection efficiency and Youden index of ELISA were 94.1%and 0.89 respectively,being high-er than those of IHA and gold marked method. Conclusion The sensitivity and specificity of the ELISA method for Toxoplasma IgG antibody are higher,and in addition,it can be automated. Therefore,it is suitable for large-scale Toxoplasma IgG antibody screening.