UNASSIGNED: Parasites of the genus Echinococcus are common worldwide and are important cestodes that cause serious infections in humans and animals. This retrospective study evaluated the indirect hemagglutination (IHA) test results of serum samples obtained from patients with a pre-diagnosis of cystic echinococcosis (CE) within ten years. In addition, the role of the IHA test results of the patients in the follow-up of the treatment and determining possible recurrences was investigated.
UNASSIGNED: The IHA test results of 2426 serum samples of patients with a pre-diagnosed CE admitted to Trakya University Health Center for Medical Research and Practice in Edirne, Turkey, between January 2011 and December 2020 were evaluated retrospectively. The data of 53 patients with CE who had medical treatment and/or postoperative follow-up serological records were evaluated.
UNASSIGNED: Of 2426 IHA tests, 376 (15.5%) were seropositive, and 2050 (84.5%) were seronegative. It was determined that 376 serum samples detected as positive belonged to 207 patients with CE. Of 207 CE patients, 109 (52.7%) were female and 98 (47.3%) were male. The most common organ involvement was the liver in 186 (89.9%) cases. Of 53 patients, 16 were considered relapse cases. The median follow-up period for 16 recurrent cases was 31.8 (1-77) months. Our results showed a statistically significant correlation between long-term serological follow-up and recurrence detection (P=0.034).
UNASSIGNED: Long-term serological follow-up after treatment is considered useful in determining possible recurrent cases. CE is an important public health problem for endemic regions, including our country, and we think our study results will contribute to the status and follow-up of the disease.

Although great strides have been achieved, schistosomiasis japonica remains a major public health concern in China. Immunodiagnostics have been widely accepted as the first choice in large-scale screening of Schistosoma japonicum human infections, and indirect hemagglutination test (IHA), enzyme-linked immunosorbent assay (ELISA), and dipstick dye immunoassay (DDIA) are currently the three most common immunological tests for the diagnosis of S. japonicum human infections in China. This meta-analysis aimed to comprehensively assess the performance of IHA, ELISA, and DDIA for the field diagnosis of S. japonicum human infections. A total of 37 eligible publications were enrolled in the final analysis, including 29 Chinese publications and 8 English publications. No significant heterogeneities were detected among the studies reporting ELISA (I2 = 88%, p < 0.05), IHA (I2 = 95%, p < 0.05), or DDIA (I2 = 84%, p < 0.05). DDIA showed the highest pooled sensitivity (90.8%, 95% CI: 84.6% to 94.7%) and IHA presented the highest pooled specificity for detection of S. japonicum human infections (71.6%, 95% CI: 65.9% to 76.7%). Summary receiver operating characteristic (SROC) curve analysis showed that IHA exhibited the highest area under the SROC curve (AUC) (0.88, 95% CI: 0.85 to 0.9), and ELISA presented the lowest AUC (0.85, 95% CI: 0.82 to 0.88). Deeks’ funnel plots indicated no publication bias. IHA presented the highest sensitivity in medium-endemicity regions and the highest specificity for diagnosis of S. japonicum human infections in low-endemicity regions, and ELISA showed the highest diagnostic sensitivity in high-endemicity regions and the highest specificity in medium-endemicity regions, while DDIA exhibited the highest diagnostic sensitivity in high-endemicity regions and the highest specificity in low-endemicity regions. IHA and DDIA presented a higher efficiency for the diagnosis of S. japonicum human infections in marshland and lake regions than in hilly and mountainous regions, while ELISA showed a comparable diagnostic sensitivity between in marshland and lake regions and hilly and mountainous regions (88.3% vs. 88.6%), and a higher specificity in marshland and lake regions than in hilly and mountainous regions (60% vs. 48%). Our meta-analysis demonstrates a comparable diagnostic accuracy of IHA, ELISA, and DDIA for S. japonicum human infections, and the diagnostic sensitivity and specificity of IHA, ELISA, and DDIA vary in types and infection prevalence of endemic regions. DDIA combined with IHA is recommended as a tool for screening chemotherapy targets and seroepidemiological surveys during the stage moving towards schistosomiasis elimination in China. Further studies to examine the effectiveness of combinations of two or three immunological tests for diagnosis of S. japonicum human infections are warranted.

Toxoplasma gondii and Chlamydia are common protozoan pathogens, which can pose health risks to people around the world and cause considerable economic losses. Although information on the seroprevalence of T. gondii and Chlamydia in chickens can be found in China, knowledge on the infection of these two diseases in rural chickens, ducks, and geese is limited. Therefore, blood samples from 377 chickens, 268 ducks, and 379 geese were taken from rural areas in seven cities in northeastern China, and their seropositivity was analyzed by the indirect hemagglutination antibody (IHA) test with a cutoff titer of 1:64. The overall seroprevalence of T. gondii and Chlamydia was 10.6% and 21.0%, respectively. Moreover, the free-range poultry (20.75% and 30.55%) have significantly higher seroprevalences than caged poultry (5.47% and 15.66%) (p < 0.001). Moreover, the seroprevalence of T. gondii in older and younger poultry was found to be 5.48% and 12.89%, and those in Chlamydia were 23.53% and 15.16%, respectively. There were significant differences between different ages (p < 0.05). But regarding the prevalence of both, it is not clear in this way which one is the prevalence for younger and older for each specific pathogen. Logistic regression analysis suggested that geography were considered as a risk factor for T. gondii infection in this study. Our study is the first report on the seroprevalence of T. gondii and Chlamydia in poultry in rural areas of Jilin Province, China. These data reflect that T. gondii and Chlamydia are widespread in poultry in northeastern China, leading to a risk of infection in human health. Therefore, the prevention and control of Toxoplasma and Chlamydia infection in poultry, other animals, and humans should be strengthened.

OBJECTIVE: This study aimed to assess available assay methods for infectious bursal disease (IBD) diagnosis and seromonitoring in local birds. It also sought to know the prevalence of IBD antibodies among local chickens and guinea fowls in Kwara state, North Central Nigeria.
METHODS: Sera were obtained from local chickens and guinea fowls and IBD virus (IBDV) antibodies were assayed using enzyme-linked immunosorbent assay (ELISA), indirect hemagglutination (IHA) test, and agar gel immunodiffusion (AGID) test.
RESULTS: A total of 265 sera were obtained from local birds during dry and wet seasons. ELISA recorded the highest prevalence of 81.1% (215/265) while IHA and AGID detected IBDV antibodies in 183 (69.1%) and 122 (46%) birds, respectively. Significant differences were established for IBD-positive sera based on the assay method used, bird species, and seasons.
CONCLUSIONS: This study indicated that ELISA is the most sensitive and reliable assay method while AGID is the least. It also showed that there is a high prevalence of IBDV antibodies among local birds which were not vaccinated, and this implies a high IBDV activity among these bird species in the study area. This may have significant epidemiological implications on the spread of the virus to exotic bird reared in the rural areas on a commercial scale. Thus, this study suggests continuous surveillance, awareness campaign, and advocacy for vaccination of indigenous birds against IBD.

An indirect hemagglutination (IHA) test that could detect antibodies against Haemophilus parasuis was developed. The full-length cDNA sequence of the oligopeptide permease ABC transporter membrane protein (OppA) gene was cloned, and inserted into the prokaryotic expression vector pET-30a(+) to construct recombinant plasmid pET-30a-OppA. The recombinant OppA protein was expressed partly in soluble form in Escherichia coli BL21 (DE3) and then purified by Ni(2+) column. Furthermore, the recombinant OppA protein was used as an antigen to develop an IHA assay for detecting antibodies against H. parasuis. Results showed that this IHA test could detect species-specific antibodies against H. parasuis. Compared with currently available ELISA, the IHA test had a sensitivity of 85.0% and a specificity of 95.0%. The overall agreement between these two methods was 90.0%. The developed IHA test was used to evaluate the seroprevalence of H. parasuis in Hubei Province, China. The H. parasuis seroprevalence rate ranged from 5.5% to 26.2% in 325 tested clinical serum samples that were collected from three different pig farms in Hubei Province, China. The IHA test developed in this study will greatly contribute to the epidemiological surveys and immunization surveillance of H. parasuis.

A case of primary pneumonic plague (PPP) caused by Yersinia pestis is reported. This case occurred in the largest plague area in China. The patient died after contact with a dog that had captured an infected marmot. Three of 151 contacts were shown to be positive for antibody against F1 antigen by indirect hemagglutination assay, but none had clinical symptoms. There was no secondary case.

Toxoplasma gondii (T. gondii), a zoonotic parasite infects almost all warm-blooded animals and causes significant economic losses. To date, however, it is still unclear whether yaks from the Qinghai-Tibetan plateau of China are exposed to T. gondii. On the present study, a survey was conducted for the first time, to investigate the seroprevalence of T. gondii infection in yaks (Bos grunniens) on the Qinghai-Tibetan Plateau (Qinghai, Tibet, Hongyuan area of Sichuan province). A total of 905 and 736 serum samples were collected from yaks in these areas in 2012 and 2013, respectively and assayed for T. gondii antibodies by an indirect hemagglutination test (IHA). The results showed that seroprevalence on plateau was 21.7% and 29.1% in 2012 and 2013, respectively with the prevalence of 22.4%, 19.4% and 25.5% in 2012 for Qinghai, Tibet and Hongyuan of Sichuan, respectively and of 26.4%, 27.0% and 33.7% for these three regions in 2013, respectively. The present survey indicated that the infection with T. gondii in yaks was widely spread in recent years on the plateau causing a high risk factor for animals and humans.