Non- fumigatus Aspergillus infection associated with a negative Aspergillus precipitin test in patients with chronic pulmonary aspergillosis

Aspergillus antibody testing is key for the clinical diagnosis of chronic pulmonary aspergillosis (CPA) with high sensitivity. However, false-negative results in patients with CPA might be obtained, depending on the Aspergillus species. The aim of this study was to investigate which factors are associated with false-negative results in Aspergillus precipitin tests and whether the sensitivity of precipitin tests in CPA is influenced by Aspergillus fumigatus and non- fumigatus Aspergillus species. Between February 2012 and December 2020, 116 consecutive antifungal treatment-naïve patients with CPA were identified and included in this retrospective chart review. Aspergillus species isolated from the respiratory tract of patients were identified by DNA sequencing. Characteristics of patients with positive and negative results for Aspergillus precipitin tests were compared. The sensitivity of the Aspergillus precipitin tests was compared between patients with A. fumigatus -associated CPA and non- fumigatus Aspergillus -associated CPA. A non- fumigatus Aspergillus species was the only factor significantly associated with negative Aspergillus precipitin test results in patients with CPA in the multivariate analysis (hazard ratio: 8.3, 95% confidence interval: 3.2–22.1, p < 0.0001). The positivity of the Aspergillus precipitin test in patients with non- fumigatus Aspergillus -associated CPA was lower than that in patients with A. fumigatus -associated CPA (84.8% vs. 37.9%; p < 0.0001). These results revealed that the presence of non- fumigatus Aspergillus -associated CPA should be considered with a negative Aspergillus precipitin test; this finding may prevent diagnostic delay or misdiagnosis for CPA.

Prevention of trichinellosis on fur farms

The purpose of the research is analysing a complex of veterinary and sanitary preventive measures against trichinellosis on fur farms.Materials and methods. The system of measures against trichinellosis is based on creating conditions on fur farms that are aimed at prevention of the invasion, and includes occasional immunological screening of animals, examination of dead animals for trichinellosis and observation of veterinary, sanitary and zootechnical requirements for animal management.Results and discussion. The sero-epizootic monitoring methods of elderly animals implemented on farms based on ELISA and Capillary Ring Precipitin Test allows us to identify infected animals and exclude them from the technology system of maintenance and breeding. The general situation of trichinellosis can be determined by results of studies by a compression or enzyme methods of animal carcasses during the period of mass slaughter for fur.

Diseases connected with work in hay in Iceland. Causes and scientific studies

Diseases connected with work in hay have been known in Iceland for a long time. In 1981 scientific studies of these diseases were started in Iceland at the request of the Farmers Union. The results of these studies are summarized in this article. In studies of hay a great amount of storage mites, moulds and thermophilic actinomycetes (microlyspora faeni) were found in addition to allergens from mice and pollen. Symptoms caused by hay dust were mainly from nose and eyes in people with positive skin tests, but cough, dyspnea and fever were equally common in those with negative skin tests. The most common causes of allergy in farming families were storage mites and cattle, but allergy to cats, dogs and grass pollen were less common rurally than in the Reykjavik area. When comparing individuals working in heavy hay dust with those working in cleaner air, the former group had a higher likelihood of having a positive precipitin test against micropolyspora faeni, fever after work in hay and airway obstruction. It was shown that Icelandic farmers were more likely to get emphysema than other people irrespective of smoking. In a large study of homes in the Reykjavik area almost no mites were found. In spite of this, positive specific IgE tests against dust mites were equally common as in Uppsala, Sweden, where dust mites were found in 16% of homes. In further studies it was found, that 57% of people in the study had been more and less exposed to hay dust. They had either been raised on a farm, been on a farm in the summer during childhood or owned horses and fed them with hay. We have argued that cross allergy to storage mites may be the cause of a rather common allergy to house dust mites. A new study of middle-aged individuals has shown that allergy to storage mites is a little more common in the Reykjavik area than in Aarhus, Bergen or Uppsala. The most likely explanation is that they have more often been exposed to hay dust.

SURVEY OF ARIEMERELLA ANATIPESTIFEROUTBREAK IN SOUTHERN TAIWAN DUCK FARMS

A septicemic outbreak in southern Taiwan duck farms in 2014 resulted in high mortality of ducklings. Samples from oral or cloacal sites of affected Muscovy and Pekin ducks were collected and the identity of the field isolates was confirmed using Riemerella anatipestifer (RA) 16S rRNA and outer membrane protein A (OmpA)-specific primers in polymerase chain reactions (PCR), with 15 isolates found positive for both 16S rRNA and OmpA. Detection of both the 16S rRNA and OmpA genes could be a rapid PCR test for RA. Serotyping of the isolates using gel-diffusion precipitin test identified serotypes 1, 4, 6, 17, and 19 while a number of isolates were unidentifiable. Sequence analysis of the OmpA gene found high identity (99.0–99.7%) among isolates in Taiwan. These results indicate that RA remains as a significant cause of duck septicemic disease in southern Taiwan.

Deteksi porfirin besi pada pakan darah nyamuk liar antropofilik menggunakan uji benzidine

The existence of human blood in mosquito’s bloodmeal is the characteristic of mosquitoes that bite humans (anthrophophilic). Anthropophilic is one of the indicator to determine the vectorial competence to assess effective and efficient vector. The anthropophilic characteristic was measured by detection of human blood using precipitin test. Benzidine test can be used to detection iron porphyrin through oxidation reaction and catalyzed by hemoglobin as peroxidase enzyme. Heme detection of mosquitoe’s bloodmeal using benzidine in Indonesia has not been reported yet. This study was aimed to obtain the effectiveness of benzidine test to detection human blood in antrophophilic mosquito’s bloodmeal. The mosquitoes were collected using human bait and sweeping collection technique at morning (06:00-09:00), afternoon (15:00-18:00), and in the night (20:00-00:00), and then determine by benzidine test. The results showed that from the collected mosquitoes there were 158 female mosquitoes of Aedes spp and Culex spp. The benzidine test showed 155 female mosquitoes showed discoloration on the indicator and 3 female mosquitoes did not. Conclusion: Benzidine test was effective to detection human blood from the mosquito’s bloodmeal to determine anthrophophilic mosquitoes.Keywords: anthropophilic, bloodmeal, benzidine. Abstrak: Adanya darah manusia dalam pakan darah nyamuk merupakan ciri dari nyamuk yang memiliki kesukaan menggigit hospes manusia (antropofilik). Sifat antropofilik nyamuk adalah salah satu indikator dalam penilaian kompetensi vektorial untuk menilai vektor yang efektif dan efisien. Penilaian sifat antropofilik dilakukan melalui penilaian pakan darah dengan uji presipitasi. Tes benzidine adalah salah satu uji yang dapat dilakukan karena efektif dalam mendeteksi porfirin besi (heme) melalui reaksi oksidasi yang dikatalisis oleh heme sebagai enzim peroksidase. Deteksi porfitin besi pada pakan darah nyamuk menggunakan benzidine belum banyak dilaporkan di Indonesia. Tujuan penelitian ini yaitu untuk mengetahui apakah nyamuk yang mengisap darah hospes manusia (antropofilik) dapat dideteksi dengan uji benzidine. Penelitian dilakukan dengan menangkap nyamuk betina menggunakan umpan manusia dan sweeping pada jam puncak menggigit nyamuk yaitu pagi (06:00-09:00), sore (15:00-18:00), dan malam (20:00-00:00) lalu dilakukan tes benzidine. Hasil: Pada penangkapan nyamuk ditemukan 158 ekor nyamuk betina yang terdiri dari genus Aedes spp dan Culex spp. Pada uji presipitasi ditemukan 155 ekor nyamuk mengalami perubahan warna yang bervariasi pada indikator dan 3 ekor nyamuk tidak berubah warna. Simpulan: uji benzidine dapat dilakukan untuk penilaian sumber pakan darah nyamuk dalam menentukan sifat antropofilik nyamuk. Kata kunci: antropofilik, pakan darah, benzidine.

Evaluation of a Quantitative Serological Assay for Diagnosing Chronic Pulmonary Aspergillosis

The purpose of this study was to evaluate the clinical utility of a quantitativeAspergillusIgG assay for diagnosing chronic pulmonary aspergillosis. We examinedAspergillus-specific IgG levels in patients who met the following criteria: (i) chronic (duration of >3 months) pulmonary or systemic symptoms, (ii) radiological evidence of a progressive (over months or years) pulmonary lesion with surrounding inflammation, and (iii) no major discernible immunocompromising factors. Anti-AspergillusIgG serum levels were retrospectively analyzed according to defined classifications. MeanAspergillusIgG levels were significantly higher in the proven group than those in the possible and control groups (P< 0.01). Receiver operating characteristic curve analysis revealed that theAspergillusIgG cutoff value for diagnosing proven cases was 50 mg of antigen-specific antibodies/liter (area under the curve, 0.94; sensitivity, 0.98; specificity, 0.84). The sensitivity and specificity for diagnosing proven cases using this cutoff were 0.77 and 0.78, respectively. The positive rates ofAspergillusIgG in the proven and possible groups were 97.9% and 39.2%, respectively, whereas that of the control group was 6.6%. The quantitativeAspergillusIgG assay offers reliable sensitivity and specificity for diagnosing chronic pulmonary aspergillosis and may be an alternative to the conventional precipitin test.

Comparative Study of the Accuracy of Different Techniques for the Laboratory Diagnosis of Schistosomiasis Mansoni in Areas of Low Endemicity in Barra Mansa City, Rio de Janeiro State, Brazil

Schistosomiasis constitutes a major public health problem, with an estimated 200 million people infected worldwide. Many areas of Brazil show low endemicity of schistosomiasis, and the current standard parasitological techniques are not sufficiently sensitive to detect the low-level helminth infections common in areas of low endemicity (ALEs). This study compared the Kato-Katz (KK); Hoffman, Pons, and Janer (HH); enzyme-linked immunosorbent assay- (ELISA-) IgG and ELISA-IgM; indirect immunofluorescence technique (IFT-IgM); and qPCR techniques for schistosomiasis detection in serum and fecal samples, using the circumoval precipitin test (COPT) as reference. An epidemiological survey was conducted in a randomized sample of residents from five neighborhoods of Barra Mansa, RJ, with 610 fecal and 612 serum samples. ELISA-IgM (21.4%) showed the highest positivity and HH and KK techniques were the least sensitive (0.8%). All techniques except qPCR-serum showed high accuracy (82–95.5%), differed significantly from COPT in positivityP<0.05, and showed poor agreement with COPT. Medium agreement was seen with ELISA-IgG (Kappa = 0.377) and IFA (Kappa = 0.347). Parasitological techniques showed much lower positivity rates than those by other techniques. We suggest the possibility of using a combination of laboratory tools for the diagnosis of schistosomiasis in ALEs.