Ziehl-Neelsen Staining Technique Research Articles

Performance of fine needle aspiration cytology and Ziehl-Neelsen staining technique in the diagnosis of tuberculosis lymphadenitis

IntroductionProper diagnosis of tuberculosis (TB) lymphadenitis is critical for its treatment and prevention. Fine needle aspirate cytology (FNAC) is the mainstay method for the diagnosis of TB lymphadenitis in Ethiopia; however, the performance of FNAC has not been evaluated in the Eastern Region of Ethiopia. This study aimed to evaluate the performance of FNAC and Ziehl-Neelsen (ZN) staining compared with that of GeneXpert for the diagnosis of TB lymphadenitis.MethodsFine needle aspiration (FNA) specimens collected from 291 patients suspected of having TB lymphadenitis were examined using FNAC, ZN, and GeneXpert to diagnose TB lymphadenitis. Gene-Xpert was considered the reference standard method for comparison. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and kappa coefficient were determined using SPSS version 25.ResultsThe sensitivity, specificity, PPV, and NPV of ZN for diagnosing TB lymphadenitis were 73.2%, 97.4%, 96.2%, and 80.1% respectively. There was poor agreement between ZN and GeneXpert (Kappa=-0.253). The sensitivity, specificity, PPV, and NPV of FNAC were 83.3%, 94.8%, 93.5%, and 86.3% respectively. There was moderate agreement between the FNAC and GeneXpert (Kappa = 0.785).ConclusionThe fine needle aspiration cytology (FNAC) is a more sensitive test for the diagnosis of TB lymphadenitis than ZN. The FNAC showed a moderate agreement with the GeneXpert assay. This study recommends the FNA GeneXpert MTB/RIF test in preference to FNAC for the diagnosis of TB lymphadenitis to avoid a missed diagnosis of smear-negative TB lymphadenitis.

Cryptosporidium infection in captive wild animals at Sanda Kyarimi Zoo in Maiduguri, Nigeria

Wild mammals are essential food sources for man and animal predators. Cryptosporidium species have a broad host range, including wildlife, which serve as crucial disease reservoirs for domestic animals and humans with a potential public health concern. The scarcity of information on the incidence of cryptosporidiosis among wild animals in North-eastern Nigeria necessitated the present study, which investigated the occurrence of Cryptosporidium oocysts among captive wild mammals in Maiduguri. Faecal samples collected from Artiodactyla/Proboscidae (n=9), Carnivores (n=7), Primates (n=9), Reptilia (n=4), and Rodentia (n=2) were examined using the ZiehlNeelsen staining technique to detect Cryptosporidium oocyst. Of the 31 captive mammals examined, 17 (54.8%), 14 (45.2%), 9 (29.0%) and 22 (71.0%) were respectively classified as males, females, young and adults. A total of 12 (38.7%; 95% CI: 23.7, 56.2) out of the 31 examined samples were positive, with a higher prevalence of 57.1% (95% CI: 25.0, 84.2) observed among carnivores compared to the other animals. There was no statistical association (p > 0.05) between the occurrence of Cryptosporidium oocysts and sex as well as the age of the individual mammal species examined. This paper underscores the role of anthroponotic and zoonotic transmission at the human-wildlife interface in zoological gardens (Zoo) and parks worldwide.

Prevalence and risk estimates of Cryptosporidium oocysts infection associated with consumption of raw-eaten vegetables in Maiduguri metropolis LGAs, Northeast Nigeria

Cryptosporidium is one of the most important protozoan parasitic pathogens, and it is a common cause of diarrhoea in humans, domestic animals, and wild vertebrates and has serious public health threats. A cross-sectional study was designed to determine the prevalence of Cryptosporidium oocysts in raw-eaten vegetables in Maiduguri Metropolitan Council (MMC) and Jere Local Government Areas (LGAs). A total of 400 samples were collected from four (4) different locations, namely Tashan Bama, Gomboru, and Monday Markets (n = 100), while fifty (n = 50) each from 202-Vegetable-Vendors and Unimaid Commercials. A total of 16 visits were conducted in all the sampling areas (twenty-five samples per visit). The Cryptosporidium oocysts were detected using the Modified Ziehl–Neelsen Staining Technique. The locations, sources, and types of raw-eaten vegetables were also assessed. The oocysts were confirmed (100×) as bright pink spherules. Data generated were analyzed using IBM-SPSS V23.0, and p ≤ 0.05 was considered significant. Out of the total samples (n = 400) analyzed, cabbage appeared to have the highest number of 10 (12.5%) of Cryptosporidium oocysts detected, while Tomato and garden egg had 9 (11.3%) and 1 (1.2%), respectively. There was a statistically significant association (χ2 = 12.5, P = 0.014) between the presence of Cryptosporidium oocysts in raw-eaten vegetables and vegetable types. Among the sources of the vegetables sampled, Alau had the highest number of Cryptosporidium oocysts, 15 (12.5%), followed by Kilari-Abdullahi and Zabarmari sources with 4 (10.0%) and 4 (5.0%), respectively. However, Jetete appeared to have the least number 2 (2.5%) of oocysts, and there was a statistically significant association (χ2= 10.4, P = 0.034) between the presence of Cryptosporidium oocysts and the sources of vegetables and fruits. The study concludes that the raw-eaten vegetables sampled from Maiduguri Metropolis were contaminated with Cryptosporidium oocysts. The study recommends that all raw-eaten vegetables should be from cleaned sources and washed before consumption. Consumers should be enlightened on the hygienic measures in the food chain in line with the Hazard Analysis and Critical Control Points (HACCP) principles.

Enteric Protozoan Parasitosis and Associated Factors among Patients with and without Diabetes Mellitus in a Teaching Hospital in Ghana.

Enteric protozoa infections (EPIs) could worsen clinical outcomes in patients with diabetes mellitus and therefore requires prompt and accurate diagnosis and attention. This study aimed to determine the burden of EPIs and their associated factors among patients with and without diabetics at the Komfo Anokye Teaching Hospital (KATH) in Ghana. Again, the diagnostic performance of parasitological techniques routinely used for diagnosis was assessed. A total of 240 participants (made up of 140 patients with diabetes and 100 patients without diabetes) were recruited into the study by simple random sampling from November 2020 to May 2021. Stool samples of participants were collected, along with their demographic information, and examined using the saline direct wet mount (DWM), formol-ether concentration (FEC), and modified Ziehl-Neelsen staining (ZNS) techniques for the presence of enteric protozoans. Enteric protozoa were found among 62/140 (44.3%) diabetic patients and 13/100 (13.0%) nondiabetic patients. The predominant protozoa identified were Cryptosporidium spp. (17.86%) among patients with diabetes and Blastocystis hominis (7.0%) among patients without diabetes. EPI was associated with diabetes mellitus status (AOR = 3.48, 95% CI, 1.55-7.79), having diabetes for more than five years (AOR = 3.83, 95% CI, 1.65-8.86) and having comorbidity (AOR = 2.93, 95% CI, 1.33-6.45). The FEC technique had the highest sensitivity (100.0%), specificity 94.3% (95% CI, 91.35-97.22), and accuracy 95.0% (95% CI, 88.54-98.13) when compared to other techniques for diagnosis. EPIs are a significant health problem among patients with diabetes at KATH, and therefore antiparasitic drugs should be included in their treatment protocols for better health outcomes. Again, the FEC technique has demonstrated better performance in detecting EPIs and is therefore recommended to achieve early and accurate diagnosis of EPIs.

The diagnosis of nontuberculous cervicofacial lymphadenitis: A systematic review

BackgroundNontuberculous mycobacterial cervicofacial lymphadenitis (NTMCL) is an uncommon condition detected in young immunocompetent children who typically present with a nontender neck mass. Various tests have been proposed to assist in the work-up of suspected NTMCL, with varying diagnostic utility. This systematic review investigates the sensitivity of the various diagnostic methods used in the work-up of pediatric NTMCL. MethodsA systematic review in accordance with PRISMA guidelines was performed using the Pubmed, EMBASE, and Web of Science databases. Searches were filtered for English language studies published prior to 05/10/22. Studies meeting criteria included studies featuring 15+ pediatric patients with confirmed or suspected NTMCL. Studies with any reported diagnostic methodology used in the workup of NTMCL were included. ResultsOf 836 abstracts/articles reviewed, 21 studies met inclusion criteria. Diagnostic methods included culture(n = 11 studies), PPD-Tb(Tuberculin)(n = 12), PPD-Scrofulaceum, −Avium, or -Kansasii(n = 6), staining techniques(n = 4), IGRA(n = 3), and ultrasound(n = 2). All studies had an overall low risk of bias.Among patients confirmed to have NTMCL based on PCR and/or culture, the most sensitive tests were PPD-A(0.94, 95 % CI 0.91 to 0.97; n = 210 patients) and PPD-S(0.75, 95 % CI 0.68 to 0.81; n = 171). Auramine and Ziehl-Neelsen staining techniques had moderately high sensitivity(0.85 and 0.60 respectively), though were limited by low patient numbers(n = 20). PPD-Tb(0.45, 95 % CI 0.39 to 0.50; n = 300) and IGRA(0.02; 95 % CI 0 to 0.06; n = 48) demonstrated poor sensitivity.Among patients suspected to have NTM lymphadenitis based on global assessment, the most sensitive tests included combined PPD-S + A + K(0.92, 95 % CI 0.86 to 0.98; n = 85), PCR(0.82, 95 % CI 0.75 to 0.88; n = 136), and PPD-A(0.72, 95 % CI 0.62 to 0.81; n = 84). Culture showed a sensitivity of 0.54(95 % CI 0.50 to 0.58; n = 494). PPD-K, PPD-S, IGRA, and staining techniques demonstrated lower sensitivity. ConclusionsThis systematic review is the largest study investigating the sensitivity of the various diagnostic methods used in the work-up of pediatric NTMCL. Patients with clinical suspicion for NTMCL and a positive PPD-Tb should first have tuberculous lymphadenitis ruled out with IGRA. Patients with a positive PPD-Tb and negative IGRA and high clinical suspicion for NTMCL can undergo presumptive surgical intervention. Patients with a negative PPD-Tb can undergo NTM antigen skin testing if available, or if high clinical suspicion exists, surgical intervention to reduce tissue burden and elicit additional tissue data.

The Intensity of Infection and Public Health Perception of Potentially Zoonotic Intestinal Parasites of Dogs in Kwara Central, Nigeria

Background: The close relationship between dogs and humans and the possibility of intestinal parasite transmission from dogs to humans calls for frequent assessment of these potential zoonotic intestinal parasites in dogs and the possibility of their transmission to humans. Objectives: This study aimed to determine the presence, intensity of infection, and public health perception of potentially zoonotic intestinal parasites in dogs of Kwara Central, Nigeria. Methods: The study was conducted in 28 locations in Kwara Central Senatorial District of Kwara State, Nigeria. Three hundred and five healthy dogs were sampled. Two hundred and thirty respondents (dog owners or handlers) were questioned using a well-structured questionnaire containing open-ended and closed-ended questions. Fecal samples from the sampled dogs were subjected to the direct fecal smear technique, simple fecal centrifugation flotation technique, formalin-ethyl acetate concentration technique, and the modified Ziehl-Neelsen staining technique. Oocysts or eggs per gram of feces were counted using the modified McMaster technique. Results: Seven different intestinal parasites (Ancylostoma spp., Cryptosporidium spp., Dipylidium caninum, Isospora spp., Strongyloides stercoralis, Toxocara spp., and Uncinaria stenocephala) were detected, with a prevalence ranging from 2.30% to 25.25%. Of these parasites, 6 were zoonotic. The mean intensities of infection were 91.43 eggs per gram (EPG) for D. caninum¸ 96.52 EPG for S. stercoralis, 129.36 ±28.12 oocysts per gram (OPG) for Isospora spp., 165.17±19.88 for Toxocara spp., 240.00±44.42 for EPG for U. stenocephala, and 303.64±31.83 EPG for Ancylostoma spp. Some dog owners and handlers were not cautious about possible zoonotic parasite transmission from dogs. Conclusion: Zoonotic intestinal parasites of dogs are present and prevalent in Kwara Central, Nigeria. There is a need to educate the public on the possibility of zoonotic parasite transmission to humans.

Occurrence of Gastrointestinal Parasites among Patients Attending Designated Tuberculosis Clinics in Rivers State, Nigeria

Diseases of gastrointestinal parasites remain a major public health concern. This study was aimed at determining the occurrence of gastrointestinal parasites among patients attending designated tuberculosis clinics in Rivers State, Nigeria. The clinics included Chest clinic, Rumuigbo, General hospital, Ahoada and Meridian hospital. The study was conducted between July 2020 and August 2021. Stool and blood samples were collected from 1288 participants and examined for the presence of ova, cysts, oocyst and trophozoites of gastrointestinal parasites using formol-ether concentration and Modified Ziehl-Neelsen staining techniques. ELISA was used to examine the blood samples for the presence of Cryptosporidium spp. and Giardia lamblia. Out of the 1288 patients examined, 580 (45%) were infected and this was statistically significant (p<0.05). Gastrointestinal parasites identified included Ancyclostoma spp., Ascaris lumbricoides, Cryptosporidium spp, Entamoeba histolytica, and Giardia lamblia. Cryptosporidium spp. was the most prevalent (p<0.05). Females had a higher prevalence (55.9%) than males (44.1%), and the age group 11-20 years were most infected. The occurrence of gastrointestinal parasite infection was higher in the wet season (p<0.05). Sources of drinking water and housing types were risk factors that had a significant influence on the infection (p<0.05). The gastrointestinal parasite was not influenced by the occupation, as well as the educational levels of the participants. The study showed that tuberculosis patients were more infected than non-tuberculosis patients, and occurrence was higher in rural areas than in urban areas; both were significant (p<0.05). Detection of Giardia lamblia and Cryptosporidium using non-ELISA and ELISA techniques were not statistically significant (p>0.05). The study showed a higher prevalence of infection; therefore, there is a need to enhance health education on the mode of transmission of gastrointestinal parasites and improve on personal and environmental hygiene of tuberculosis patients and the population as a whole; to reduce the occurrence of infection

Role of Bleach Concentration Method for Detection of Acid-fast Bacilli (AFB) in Sputum using Conventional Ziehl-Neelsen (ZN) Staining Technique

Sputum microscopy is the most important tool for the detection of Mycobacterium tuberculosis in peripheral laboratories. Sodium hypochlorite concentration technique prior to sputum microscopy may improve the detection of AFB bacilli over direct Ziehl Neelsen’s staining method. A prospective study was conducted at Kasturba Medical College, Manipal. Consecutive sputum samples were collected for 3 months. ZN stained smears were made directly of fresh specimens and of specimens that were processed with 3.5% sodium hypochlorite (NaOCl), from each patient. Then, ZN stained smears were observed under light microscopy. A total of 239 samples were collected. The yield of positive smears with ZN staining after NaOCl centrifugation was higher than that with microscopy after direct ZN stain. The percentage increase yield of ZN staining after NaOCl centrifugation over direct ZN staining was 3.3% (8/239). Bleach centrifugation can help in increasing the yield of positivity in sputum smear.

Epidemiological studies of gastrointestinal parasites infecting dogs in Kwara Central, North Central, Nigeria

Dogs are the most cosmopolitan pets of humans and as such a means of transmitting zoonotic parasites to their owners. This study was designed to investigate the diversity, prevalence, pattern of infection, intensity of infections, and the risk factors associated with gastrointestinal parasites of dogs in Kwara Central, North Central, Nigeria. Three hundred and five clinically healthy dogs were sampled. Faecal samples were subjected to the direct smear, simple faecal centrifugation flotation, formol-ether concentration, and the Modified Ziehl-Neelsen staining techniques. Oocysts/eggs per gram of faeces were counted using the modified McMaster technique. Data were analysed using univariate logistic regression, multivariate logistic regression, and the one-way analysis of variance (ANOVA). A p -value of < 0.05 was considered significant for all analyses. One hundred and sixty-six dogs were positive for at least one species of gastrointestinal parasite, representing 54.43% (95% CI: 44.81 – 59.96) of the sampled population. The study identified Cystoisospora species (15.41%), Cryptosporidium species (25.25%), Ancylostoma species (25.25%), Toxocara canis (19.02%), Strongyloides stercoralis (7.54%), Uncinaria stenocephala (6.89%), and Dipylidium caninum (2.30%) as the gastrointestinal parasites infecting dogs in the study area. Coinfection with more than one species of gastrointestinal parasites was a common finding in dogs. The intensity of Cystoisospora spp. among infected dogs ranged between 40 and 980 oocysts per gram of faeces, while that of helminth parasites was 40 – 1560 eggs per gram of faeces. Age, sex, breeds, body condition score, presence of ticks on dogs, the purpose of keeping dog(s), types of housing, types of feed consumed, vaccination status, and treatment with antiparasitics were predators associated with the prevalence and intensity of gastrointestinal parasites infections. Due to the zoonotic nature of most of the encountered gastrointestinal parasites, there is need for regular antiparasitic treatment, proper dog management, and adequate personal hygiene to prevent zoonosis.

Endoparasites of Leopardus pardalis (Carnivora, Felidae) rescued in the State of Rio de Janeiro.

Wild cats play an important role as top predators in the food chain and act as ecosystem regulators. However, in recent decades, many studies have demonstrated the potential effects of parasitic diseases on wild carnivore populations, including cats. This study reports on the endoparasites found in an injured and rescued specimen of Leopardus pardalis in the state of Rio de Janeiro. Fecal samples were collected and processed using five coproparasitological techniques: a simple flotation centrifugation, a zinc sulfate flotation centrifugation, a formalin-ether sedimentation centrifugation, a conical centrifuge tube technique, and a modified Ziehl-Neelsen staining technique for fecal smears. Helminth eggs belonging to the families Trichuridae and Diphyllobothriidae and the genus Toxocara were found in both sedimentation flotation techniques. Protozoan oocysts belonging to the genus Cryptosporidium were identified by modified Ziehl-Neelsen staining. These findings show that ocelots can harbor potentially zoonotic and pathogenic endoparasites. Further studies on the helminths and protofauna of these animals are necessary.

Evaluation of the genexpert Mycobacterium tuberculosis/Rifampicin assay for early detection of extrapulmonary tuberculosis and rifampicin resistance in aligarh region of Northern India

Purpose: Early diagnosis of extrapulmonary tuberculosis (TB) with simultaneous detection of rifampicin (RIF) resistance (RR) directly from the sample is a revolution brought by GeneXpert Mycobacterium TB (MTB/RIF) assay. Line probe assay (LPA) is not recommended for extrapulmonary/nonsputum specimens; GeneXpert MTB/RIF provides a diagnostic option for these. Hence, the following study aimed to evaluate the performance of GeneXpert MTB/RIF assay in nonsputum samples. Materials and Methods: A total number of 642 extrapulmonary and nonsputum respiratory samples were subjected to Ziehl–Neelsen (ZN) staining technique, fluorescent microscopy (FM), and GeneXpert MTB/RIF Assay. All samples were cultured on a solid Lowenstein–Jensen (LJ) medium and culture-positive samples were subjected to GenoType MTBDRplus LPA and drug susceptibility testing by 1% proportion method on a solid LJ medium. Results: GeneXpert MTB/RIF assay detected MTB in 25.9% (166/642) of the samples. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of ZN staining technique and FM were 21.52%, 99.35%, 91.89%, and 78.77% and 27.22%, 99.78%, 97.73%, and 80.07%, respectively. Sensitivity, specificity, PPV, and NPV of GeneXpert MTB/RIF in the detection of MTB were 93.75%, 96.53%, 90.36%, and 97.80%, and RIF RR was 92.0%, 97.74%, 88.46%, and 98.48%, respectively. LPA performed on positive culture growth showed 100% sensitivity and specificity in the detection of RIF and isoniazid resistance. Conclusion: GeneXpert MTB/RIF showed high sensitivity and specificity in detecting MTB and simultaneous RIF RR among the nonsputum samples which had a good concordance to LPA. It provides a judicious option for early detection of multidrug-resistant TB in extrapulmonary and nonsputum respiratory samples.

Detection, prevalence, and risk factors associated with Cryptosporidium infection among cattle in Kwara State, Nigeria

Cryptosporidium species cause high morbidity and sometimes high mortality rates among cattle, resulting in serious economic threats. This present study is aimed at investigating the presence, prevalence, distribution, and risk factors associated with Cryptosporidium species infection among cattle in Kwara State, Nigeria. To achieve this, 333 apparently healthy cattle were sampled from abattoirs and different cattle herds over a one-year period. Faecal samples were collected and subjected to the formalin-ethyl acetate (formol-ether) sedimentation technique. Sediments from the formol-ether sedimentation method were used for the modified Ziehl-Neelsen staining technique. The Microsoft Excel (2016) spreadsheet and the Statistical Package for the Social Sciences (SPSS, Chicago, Illinois, USA) for Windows version 22.0 were used for the data analysis. Of the cattle sampled, 99 were positive for the enteric protozoan (29.73%; 95% confidence interval (CI) = 25.07–34.85). There was no distinct pattern in the monthly prevalence of Cryptosporidium infection in cattle. Breeds of cattle, physiological status, and seasons were statistically associated with the prevalence of Cryptosporidium species in cattle. There is a need to educate pastoralists on the control and preventive measures of this enteric protozoan to improve the economy of the cattle industry and prevent possible transmission to humans in Kwara State and Nigeria in general.

Comparison of Ziehl-Neelsen Microscopy Technique and Genexpert in the Diagnosis of Tuberculosis in Sudanese Patients

Aim: The quality of tuberculosis diagnosis service is indispensable for early infection control and preventing unnecessary anti-tubercular therapy use. TB diagnosis in Sudan mainly relies on detecting tubercule bacilli using the Ziehl-Neelsen (ZN) staining technique. Thus, the current study aimed to compare the ZN microscopy with GeneXpert in diagnosing pulmonary tuberculosis (PTB) in TB laboratories center in Khartoum state, Sudan. Methods: A cross-sectional study was carried out at the TB laboratories diagnosis center in Khartoum state from April 2019 to January 2020. A total of 183 sputum samples were processed and examined by the Ziel-Neelsen (ZN) technique and GeneXpert assay for the detection of tubercle bacilli. Results: Out of 183 sputum samples analyzed, 80.9% were AFB smear-positive, of which 65.6% were male patients. Most patients (57.4%) were within the age group of 20 – 39 years old. All smear-positive samples were detected positive for Mycobacterium tuberculosis by GeneXpert. However, one case of smear-positive PTB was given a negative result by GeneXpert. These results demonstrate that GeneXpert is crucial for confirming TB cases to control TB infection and avoid unnecessary anti-tubercular drug use. Conclusion: ZN microscopy can result in false positivity, which may lead to the misuse of anti-tuberculosis drugs. A positive test should also be confirmed by the GeneXpert and culture techniques. Keywords: Mycobacterium tuberculosis, Tuberculosis, GeneXpert, Ziel-Neelsen stain

Faecal shedding of cryptosporidium oocysts in goats in Nsukka, Enugu State: a potential threat to man

Cryptosporidiosis is one of the most important diseases in young ruminants causing diarrhoea in neonates and immune-compromised animals leading to substantial economic losses both directly and indirectly in animals and animal products and also imposing public health threats as a zoonotic disease. This study aimed at investigating the occurrence of cryptosporidium oocyst in goats in Nsukka metropolis to facilitate further studies on the zoonotic transmission of the disease agent. Faecal samples were collected from household WAD goats from three randomly selected villages in Nsukka L.G.A of Enugu State. A total of 100 goats were purposively sampled, and faecal samples were collected par rectum using disposable latex gloves and transported to the Veterinary Parasitology laboratory, University of Nigeria, Nsukka for further analysis. Faecal samples were concentrated using the Formol-ether concentration method and cryptosporidium oocysts were detected using a modified Ziehl-Neelsen staining technique. The sample was considered positive when at least one oocyst with the correct morphologic characters was observed. Data obtained were analysed using the Chi-square test and the differences in the prevalence of cryptosporidium oocysts within each variable (Age, sex, and stool consistency) were compared. A probability of less than 0.05 was considered significant. The overall prevalence of cryptosporidium oocysts was 24%. There was a significant association between the prevalence of cryptosporidium oocysts and the sex of the goats sampled, while there were no significant associations between the prevalence of cryptosporidium oocysts and the age of the goats sampled and consistency of the faeces. The wide presence of these oocysts is of public health significance as apparent healthy goats were also shedding the oocysts. Efforts should be directed towards improving our management systems in order to prevent the menace of the public health threat. Further studies are recommended to provide evidence for other sources and factors that might influence cryptosporidiosis in the area.

Dairy Farm Management Practices as Risk Factors Linked to Cryptosporidium spp. Infection in Dairy Calves

Background: Cryptosporidiosis is the disease of zoonotic importance and is considered to be third major cause of diarrhoeal disease of calves worldwide causing significant economic losses. The present study aimed to link Cryptosporidium spp. infections in dairy calves with the management practices as a major risk factor. Methods: Total 401 faecal samples from dairy calves were collected from eight large (100-1000 animals) and eight medium size (30-100 animals) dairy farms located in Jabalpur (Madhya Pradesh, India). Cryptosporidium oocysts were identified in faeces by modified Ziehl-Neelsen staining (mZN) and formal ether concentration techniques. Result: The prevalence of Cryptosporidium spp. was 28.7% in dairy calves. A higher prevalence and risk of cryptosporidiosis was associated with large farms (24.9% vs. 3.74%, OR=1.96), intensive farming system (27.7% vs. 0.99%, OR=1.86), drinking ground water (27.7% vs. 0.99%, OR=1.86), dirty farms (16.7% vs. 11.6%, OR=1.90), presence of other animals at farm (15.9% vs. 12.7%, OR=1.36), absence of deworming (14.7% vs.13.9%, OR=5.09) and diarrhoea treatment practice (16.2% vs. 12.5%, OR=1.07). Multi-animal calving area, dirty calving pen and cemented floor were also identified as risk factors. Practices like feeding colostrum within one hour of birth, @ 10% b.wt./day, weaning the calves within 24 hrs and using detergent to wash feeding utensils decreased the risk of infection from 1.4 to 2 times. Calves kept confined with their dam had greater prevalence and risk of infection (17.2% vs. 11.5%, OR=5.20). The findings highlight that proactive managemental practices are beneficial for decreasing the environmental contamination and improving calf health.

Screening of specimens by Ziehl-Neelsen staining technique for the diagnosis of extra spinal musculoskeletal tuberculosis: A retrospective study

Introduction: Musculoskeletal tuberculosis is a significant form of extra pulmonary tuberculosis (EPTB) which has substantial consequences if not diagnosed and treated early. Reliable and rapid confirmation of the diagnosis is now possible by advent of Polymerase Chain Reaction (PCR), Cartridge Based Nucleic Acid Amplification Test (CB-NAAT/Gene-Xpert) and radiometric method (BACTEC) However, most of these sensitive technologies are not available at places with constrained resources. Hence, diagnosis of tuberculosis at these places, continues to rely on smear microscopy using Ziehl-Neelsen (ZN) staining. Specificity of ZN staining and microscopy is high, but its overall sensitivity is variable (20-53%). Despite of low sensitivity, it is still an easy, cheap, efficient and accessible tool due to its high specificity. Aim: Aim of the present study was to assess the role of ZN staining in diagnosis of extra-spinal musculoskeletal tuberculosis in resource limited settings. Material and methods: A retrospective study was done from 1st January 2016 to 31st December 2019 on specimens received in microbiology laboratory for ZN staining from clinico-radiologically suspected cases of extra-spinal musculoskeletal tuberculosis. The clinical information of the cases was noted from the Orthopaedics Department case files, while results of ZN microscopy were retrieved from the records maintained in Microbiology Department. Results: Specimens from 95 patients with clinico-radiologically suspected extra-spinal musculoskeletal tuberculosis were examined for Acid Fast Bacillus (AFB) by ZN staining technique. Out of 95 patients; 11 patients (11.58 %) were found to be AFB positive. Conclusion: Owing to low yield percentage of ZN staining in extra spinal musculoskeletal tuberculosis; ZN stain alone cannot be used as a tool for diagnosis of this form of tuberculosis.

Prevalence and Risk Factors of Cryptosporidium Infection Among Cats and Dogs in Qom Province, Iran

Cryptosporidiosis is an important parasitic disease that is a major health concern for animals and humans in most countries. This cross-sectional study was performed to evaluate the factors associated with the prevalence of Cryptosporidium spp. in cats and dogs in the urban and suburban regions of Qom province, Iran. Faecal samples of 220 dogs and 120 cats were examined for oocysts by formalin ether sedimentation method and Ziehl-Neelsen staining technique. The prevalence was 3.18% for dogs and 10.83% for cats. The oocysts were found in 8.16% diarrhoeic dogs and 27.27% diarrhoeic cats compared to 1.75% and 4.59% non-diarrhoeic dogs (P = 0.024) and cats, respectively (p<0.001). Prevalence was significantly higher in cats below one-year of age (27.77%) than in older cats (7.84%, P = 0.012). There was a significant difference between prevalence of cryptosporidiosis between indoor or outdoor reared animals. Dogs in rural areas had a higher infection rate (5.66%) than dogs in urban regions (0.87%, P = 0.043). The results showed that cryptosporidiosis is an important infection to be considered in differential diagnosis for diarrhoea in cats and dogs in this region. As cryptosporidiosis is a zoonotic disease, owners and veterinarians should be aware of its health considerations.

Prevalence of Intestinal Parasitic Infection among Pre-School and School-Aged Children Attending to Fann University Hospital, Dakar: Results from Retrospective Analysis

Background: Intestinal parasitic infections represent a major public health problem worldwide. Pre-school and school children have a high risk of infection. The study aimed to determine the epidemiological aspects of intestinal parasitic infections in preschool and school-aged children in Dakar, Senegal. Methods: A retrospective analysis of laboratory records from preschool and school-aged children referred to the Laboratory of Parasitology at the Fann University Hospital in Dakar, Senegal, was carried out. The analysis of the period from 2016 to 2020. Stool samples were examined for the presence of parasites using direct, formal-ether concentration method and the Modified Ziehl Neelsen staining technique. Descriptive and analytic analysis was performed with Stata MP 16.1 software. Results: The overall prevalence of intestinal parasitic infection was 26.8% (429/1603). Blastocystis sp. (34%), Entamaeba coli (28%), Giardia intestinalis (9.6%), Endolimax nana (4.9%) and Ascaris lumbricoides (3.5%) were the common parasites found. Out of the 429 children positive for intestinal parasites, protozoa parasites represent 93.9%. Single infection and mixed infection represent 83.7% and 16.3%. The most prevalent associations were E. coli + Blastocystis sp. (6.3%), E. coli + E. nana (3.3%), and G. intestinalis + Blastocystis sp. (1.9%). Children between the ages of 5 - 10 years and those over 10 years had the most parasitic infections with 28.1% [aOR = 1.91; 95% CI (1.25 - 2.89)] and 27.4% [aOR = 11.92 (1.07 - 3.07)]. According to the year of sample collection, the prevalence was higher in 2017, 32.6% [aOR = 1.49 (1.11 - 2.01]. The prevalence of intestinal parasitic infection was not significantly related to gender (p = 0.87), season (p = 0.85) and symptomatology (p = 0.19). The main clinical symptoms were dysenteric syndrome, dyspeptic disorders, constipation and abdominal pain. Intestinal parasite carriage in patients with acute diarrhea was 20.4%. In HIV positive with chronic diarrhea, the prevalence was 28.6%. Conclusion: The results showed the frequency of intestinal parasites in preschool and school-aged children with a high proportion of protozoa parasites. Children aged over 5 years were more affected. Preventive measures such as health education, improved socio-economic conditions and environmental sanitation are required for reducing their frequency.

Epidemiology and public health implications of parasitic contamination of fruits, vegetables, and water in Kwara Central, Nigeria.

Fruits and vegetables are sources of parasitic infections in humans. This study was designed to determine the epidemiology of parasitic contamination of fruits, vegetables, and water, as well as the perception of retailers, buyers, and consumers about its contamination in Kwara Central, Nigeria. A cross-sectional study design was employed for this study. A total of 160 fruits, 349 vegetables, and 51 water samples were randomly purchased/collected from thirty different markets. The samples were subjected to sedimentation and modified Ziehl-Neelsen staining techniques. All the types of fruits and vegetables sampled were contaminated with one or more parasites. Eleven different species of zoonotic parasites (6 protozoans and 5 helminths) were detected. Entamoeba coli (39.8%) and Strongyloides stercoralis (9.6%) were the most prevalent protozoan and helminth respectively. The prevalence of other protozoan parasites ranged between 21.3% (Entamoeba histolytica) and 2.3% (Balantidium coli), while that of helminths was between 5.7% (Ascaris lumbricoides) and 2.1% (Trichuris trichiura). Source of fruits and vegetables, source of manure for cultivation, the source of water for washing/wetting purpose, market type, washing of fruits and vegetables before display, the presence of children at home and in the market, and knowledge of parasitic contamination were the risk factors associated (P<0.05) with parasitic contamination of fruits and vegetables among sellers. There is a need to educate the general public on the possibilities of parasitic contamination of fruits and vegetables and its public health implications.

Determination of microsporidia infection in larvae and adult anopheles mosquitoes (Diptera: Culicidae) Northwest Ethiopia

Microsporidia are a diverse group of obligate intracellular, spore-forming parasites that infect invertebrates including mosquitoes. A few studies showed that microsporidia infection of mosquitoes is associated with larval mortality or reduced adult fecundity and lifespan. This phenomenon might be used to protect against vector-borne disease transmission. This study aimed to determine microsporidia infection in field-collected Anopheles larvae and reared adults. Anopheles larvae were collected from the field and analyzed from February to April 2022. After determining the species identity of the 4th stage larvae, they were dissected to extract their midgut while the early-stage larvae were transported to an entomological laboratory for rearing the adult in the insectary room. Similarly, after determining the species identity of adult female Anopheles mosquitoes, they were dissected to extract their midgut. Then, two thin smears for each dissected larvae and/ adults were made. Fixed preparations were stained with Giemsa and modified Ziehl-Neelsen staining techniques to detect the microsporidia. Descriptive statistics and an independent t-test were used to analyze the data. Anopheles gambiae complex was identified as the most predominant species from field-collected larvae and insectary reared adults. From the total 258 larvae and 258 adults An.gambiae complexes tissue smears examined, microsporidia were detected in 2.7% [7/258, (95%, CI: 0.8-5)] and 1.2% [3/258, (95%, CI: 0.01-2.7)] of larvae and adults respectively. The mean density of microsporidia in larvae and adults was 64.9 (± 23.4 SD) and 36 (± 8.5SD) respectively. The difference in microsporidia density between infected larvae and adults was statistically significant (F=1.77, P= 0.02). Conclusion: Significant level of microsporidia infection was detected using light microscopy. Further microsporidia identification in the genus and species level is needed.