Isolation of Mycobacterium avium and other nontuberculous mycobacteria in chickens and captive birds in peninsular Malaysia.

BACKGROUND: Mycobacterium avium complex (MAC) causes a chronic infectious in the birds known as avian mycobacteriosis. Almost all species of the birds are susceptible to MAC which consists of two closely related species of mycobacteria, that is, M. avium and M. intracellulare. This study aimed to determine the occurrence of Mycobacterium avium subsp. avium (MAA) in chickens and captive birds in selected states of Peninsular Malaysia. RESULTS: A 300 fecal samples were collected from village chickens (n = 100), layer chickens (n = 100) and captive birds (n = 100). Fecal samples were split into two aliquots for microbiological and molecular detection of MAA. Microbiology detection consisted of microscopy (Ziehl-Neelsen staining) and culture of samples decontaminated with 1% Cetylperidinium chloride and vancomycin, nalidixic acid and amphotericin B (VNA) antibiotic cocktail [vancomycin (VAN) 100 µg/ml, nalidixic acid (NAL) 100 µg/ml and amphotericin B (AMB) 50 µg/ml] onto Löwenstein-Jensen (L-J). Molecular detection (PCR-IS901) was performed to detect MAA DNA from the feces and PCR-16S rRNA and IS901 for identification of genus Mycobacterium and Mycobacterium avium sub species avium isolated onto L-J. All samples (296) were AFB negative smear. M. avium was isolated in 0.3% (1/296) samples by culture and detected in 2.5% (6/242) samples by PCR (IS901). Other mycobacteria were found in 1.7% (5/296) chickens. Of five isolates, two were identified as Mycobacterium terrae and M. engbaekii and remaining isolates were not sequenced. Birds positive for M. avium included White Pelican (n = 1) Black Hornbill (n = 1), Macaw (n = 2), Cockatoo (n = 2) and village chicken (n = 1). CONCLUSION: It is concluded that chickens and birds were infected with M. avium in selected areas of Peninsular Malaysia. Although, PCR is rapid, reliable and cost effective method for detection of M. avium in a subclinical stage, the culture of the avian feces should still be used as a reference test for the diagnosis of avian tuberculosis.

Avian mycobacteriosis in captive brolgas (Antigone rubicunda).

CASE SERIES: Avian mycobacteriosis is a significant disease of a wide range of bird species worldwide. The most common causative agent, Mycobacterium avium, is reported to also infect a range of mammals, including humans. Of 11 brolgas (Antigone rubicunda) submitted to the University of Melbourne for postmortem examination over a 10-year period, 7 were diagnosed with mycobacteriosis. All were from a wildlife park and kept in permanent enclosures as part of a breeding program. Most of the brolgas with mycobacteriosis were in poor body condition and had widely disseminated granulomas throughout the body, especially within the liver, spleen and gastrointestinal tract. Respiratory tract involvement was common, with all disseminated cases having pulmonary or air sac granulomas. Rare to moderate numbers of acid-fast organisms were detected in granulomas by histological examination. Where examined by appropriate bacteriological examinations, M. avium complex was isolated from affected tissues. CONCLUSION: This case series is the first known report of mycobacteriosis in brolgas and highlights the pathological changes seen. The complications in maintaining an avian mycobacteriosis-free breeding program and in eradication of the disease from an enclosed wildlife environment are discussed.

Prevalence of bovine and avian tuberculosis in camel herds and associated public health risk factors in Isiolo County, Kenya.

A cross-sectional study was conducted among 308 lactating camels selected from 15 herds from three different camel milk clusters in Isiolo County, Kenya, to determine prevalence of bovine and avian tuberculosis using Single Comparative Intradermal Tuberculin Skin test. Seventy-five (75) questionnaires were administered to pastoralists/herders, and focus group discussions were conducted among 3-5 pastoralists/herders selected from each camel herd to collect information on camel husbandry and health management practices and knowledge on tuberculosis in livestock and wildlife. An overall prevalence of bovine and avian reactors was 3.57 and 18.18%, respectively, with bovine and avian reactors for different clusters being 2.38, 3.82, and 4.48% and 25, 17.2, and 11.94%, respectively. There was significant difference (p < 0.05) in prevalence of bovine and avian reactors between different clusters. There was a negative correction (r = -0.1399) between herd size and bovine reactors, while there was a positive correlation (r = 0.0445) between herd size and avian reactors. The respondents indicated that camel herds are exposed to several risk factors like close contact with other herds or livestock or wildlife during grazing and at watering points. Pastoralists have poor knowledge on mode of infection and transmission of bovine or avian tuberculosis. The high prevalence of bovine and avian reactors and pastoralists' poor knowledge on mode of transmission signify potential risk to public health.

Identification and genetic characterization of polyomaviruses in estrildid and fringillid finches.

Polyomavirus infections were detected in 40 companion bird individuals belonging to a broad species range of estrildid and fringillid finches and originating from 21 different bird aviaries. Based on partial virus protein 1 (VP1) sequences, the viruses were identified as Serinus canaria polyomavirus 1 and Pyrrhula pyrrhula polyomavirus 1. Serinus canaria polyomavirus 1 was found in 18 birds belonging to one estrildid and four fringillid species. Pyrrhula pyrrhula polyomavirus 1 was detected in 22 birds of six estrildid and three fringillid species. There was a large overlap in host range. Increased mortality was frequently found in the affected bird aviaries while clinical signs were diverse. Co-infections with other viruses, bacteria or fungal pathogens were common and might have influenced the clinical signs. Sequence analyses, including partial VP1 sequences of the 40 virus strains, and full genome sequences of selected strains revealed a high genetic heterogeneity among virus subgroups of Serinus canaria polyomavirus 1 and Pyrrhula pyrrhula polyomavirus 1, indicating the existence of two virus variants for both virus species. For Pyrrhula pyrrhula polyomavirus 1, two genotypes were found that associated with the family of the finches, Estrildidae or Fringillidae.

Outbreak of Avian Tuberculosis in Commercial Domestic Pekin Ducks ( Anas platyrhynchos domestica).

Avian tuberculosis is a contagious disease affecting various domestic and wild bird species, and is caused by Mycobacterium avium . It is reported extremely rarely in commercial poultry flocks and has not been reported in commercial domestic ducks to date, with domestic ducks reported to be moderately resistant to M. avium infection. Here, we report the outbreak of avian tuberculosis in commercial Pekin duck ( Anas platyrhynchos domestica) flocks. Postmortem and histopathologic findings included nodules presenting in the visceral organs of ducks, and granulomas with central caseous necrosis surrounded by infiltrating lymphocytes. The M. avium pathogen was isolated and further identified by Ziehl-Neelsen staining and PCR based on insert sequence IS901 and the 16S rRNA gene. We highlight that avian tuberculosis not only has economic significance for the duck industry, but also presents a potential zoonotic hazard to humans.

Mycobacterium avium subsp. avium found in raptors exposed to infected domestic fowl.

We report a case of a falcon breeding facility, where raptors (both diurnal and nocturnal) were raised in contact with domestic fowl (Gallus gallus f. domesticus) infected by Mycobacterium avium subsp. avium. Fecal and environmental samples from 20 raptors and four common ravens (Corvus corax) were collected. Mycobacterium a. avium DNA was detected in feces of four raptors (bald eagle [Haliaeetus leucocephalus], eagle owl [Bubo bubo], barn owl [Tyto alba], and little owl [Athene noctua]) using triplex quantitative real-time PCR. As both the flock of domestic fowl and one of the infected raptors had the same origin (zoological collection), they might have had a common source of colonization/infection. However, the detection of M. a. avium in feces of three other raptors may point at transmission of the agent between the birds in the facility. Contact of raptors with domestic fowl infected by M. a. avium may pose a risk for transmission of the infection for them; however, raptors from the falcon breeding facility seemed to be relatively resistant to the infection.

Outbreak of Mycobacterium avium subsp. avium infection in one flock of domestic pigeons.

An outbreak of Mycobacterium avium subsp. avium infection was diagnosed in one breed of domestic pigeons (Columba livia f. domestica) in the Czech Republic. Nodular granulomatous lesions were found in 42 (9.7%) pigeons of the 435 examined; histopathologic examination of livers with gross lesions of mycobacteriosis from 15 randomly selected pigeons revealed granulomatous inflammation typical for avian mycobacteriosis in all samples. Direct Ziehl-Neelsen (ZN) microscopy and conventional culture were performed for a total of 117 liver samples (42 pigeons with nodular lesions, 55 randomly selected pigeons without nodular lesions, and 20 randomly selected squabs). Acid-fast bacilli were observed in 19 (16.2%), and conventional culture yielded growth of M. a. avium in 40 (34.2%) liver samples. A triplex quantitative real-time PCR assay based on the IS901 detection system was performed successfully in 115 liver samples and revealed M. a. avium in 63 (54.8%) of them. Mycobacterium a. avium was also detected in two squabs. Eight domestic rabbits (Oryctolagus cuniculus f. domestica) living in the breeding facility were also examined. Pyogranulomatous lesions were only found in one adult male rabbit. At necropsy, both direct ZN microscopy and culture gave negative results for mycobacteria in all examined rabbit tissues. Mycobacterium a. avium was diagnosed in a liver sample of one juvenile rabbit using triplex qPCR, suggesting that M. a. avium infection can occur as early as juvenile animals.

Mycobacterium avium Subsp. avium and Salmonella enterica serotype Typhimurium var. Copenhagen phage type DT2 in pigeons.

We report on a coinfection of Mycobacterium avium subsp. avium and Salmonella enterica serotype Typhimurium var. Copenhagen phage type DT2 in pigeons from one flock, from which squabs were occasionally consumed by humans. Triplex quantitative real-time PCR and culture methods were used for M. a. avium detection in livers and culture method was used for the detection of Salmonella sp. in samples of liver and caecum of 33 examined birds. M. a. avium was detected in a total of 31 (93.9%) and Salmonella Typhimurium in a total of 11 (33.3%) pigeons. Coinfection with both pathogens was found in 10 (30.3%), infection with Salmonella Typhimurium alone in 1 (3.0%), and infection with M. a. avium alone in 21 (63.7%) pigeons. Neither pathogen was detected in one pigeon. There was no difference in clinical symptoms exhibited by pigeons infected by M. a. avium and/or Salmonella Typhimurium. All Salmonella Typhimurium isolates were sensitive to all 15 antimicrobials tested. According to these results we emphasize good heat treatment of consumed squabs.

Avian mycobacteriosis in free-living raptors in Majorca Island, Spain.

Avian mycobacteriosis is a chronic, infectious disease caused by different species of mycobacteria, usually belonging to the Mycobacterium avium complex. From 2004 to 2007, 589 raptors brought dead or sick to a wildlife rehabilitation centre in Majorca (Balearic Islands, Spain) were necropsied. The birds belonged to 12 different species, chiefly common kestrel (Falco tinnunculus) (n=297), scops owl (Otus scops) (n=109), barn owl (Tyto alba) (n=75), long-eared owl (Asio otus) (n=58), peregrine falcon (Falco peregrinus) (n=27), and booted eagle (Hieraaetus pennatus) (n=13). Gross lesions compatible with mycobacteriosis were observed in 14 birds (2.4%) found in several locations in Majorca. They were 12 kestrels (prevalence in this species, 4.0%), one long-eared owl (1.7%) and one scops owl (0.9%), all the birds presenting white-yellowish nodules from pinpoint size to 1 cm in diameter in diverse organs, mainly in the liver, spleen and intestine. Affected organs were subjected to bacteriology and molecular identification by polymerase chain reaction and, in all cases, infection with M. avium subspecies avium was confirmed. The observed prevalences are similar to those previously observed in Holland, although the actual prevalence detected in this study is likely to be higher than reported because only birds with gross lesions were subjected to culture. Further molecular characterization with a set of six mycobacterial interspersed repetitive unit-variable number tandem repeat loci was used to sub-type the isolates in order to show the existence of possible epidemiological links. Six different genotypes were found, which points to infection from multiple foci. No temporal or geographical aggregation of the cases was observed to be associated with the presence of positive birds or with the different variable number tandem repeat allelic profiles. The most feasible origin might be water or food sources, although the reservoir of mycobacteria remains unknown.

Avian tuberculosis of zoonotic importance at a zoo on the Bogotá Andean plateau (Sabana), Colombia.

Given that exposure to captive wild animals at circuses or zoos can be a source of zoonotic infection, a case and control study was carried out with a collection of exotic fowl at a zoo in Bogotá, Colombia. The presence of Mycobacterium avium-II was directly related to the death of birds kept in the original enclosure, and of 50% of a group of sentinel birds. Failure to detect the organism in a control group of birds outside the enclosure indicated that the infection was limited to the original enclosed area. We demonstrated that M. gordonae-IV was disseminated in all organs from 1 bird with macroscopic granulomatous lesion, a finding which has not been reported previously. We emphasize the importance of establishing handling norms to reduce the risk of zoonotic transmission.

Mycobacteriosis in wild birds: the potential risk of disseminating a little-known infectious disease.

Avian mycobacteriosis is important for animal and human health; wild birds play an important role in mycobacterial species' ecology and movement. This review was aimed at reporting the role of birds in the spread of avian mycobacteriosis in human and animal populations at risk and thus a systematic review was made of PubMed, Science Direct, Scielo and Scirus databases. Mycobacteria are classified into the Mycobacterium tuberculosis complex and non-tuberculous mycobacteria; the Mycobacterium avium complex represents the most important part of the latter because it is primarily responsible for mycobacterial infection in wild birds and is a potential pathogen for mammals, especially for immunocompromised patients. The clinical signs in birds are variable as it is a chronic and debilitating disease, involving emaciated carcasses, white nodules in different organs and microscopically it presents granulomatosous multifocal inflammation. Diagnosis begins by suspicion based on clinical signs and finishes with microbiological confirmation. New diagnostic techniques include testing with DNA-RNA probes. No effective treatment is currently available and chemoprophylaxis on suspicion of infection is not recommended at the start; these factors increase the potential risk of mycobacteriosis becoming one of the most frequently documented zoonotic diseases which is difficult to treat in birds and humans. Recent concern regarding mycobacterial infection lies in the increased frequency of these opportunistic infections occurring in immunocompromised individuals and these infections' potential impact on bird conservation, this being increased by greater contact between humans and wild and captive birds.

Mycobacteriosis in wild birds: the potential risk of disseminating a little-known infectious disease / Micobacteriosis en aves silvestres: riesgo potencial de diseminación de una infección poco conocida en el mundo

Avian mycobacteriosis is important for animal and human health; wild birds play an important role in mycobacterial species' ecology and movement. This review was aimed at reporting the role of birds in the spread of avian mycobacteriosis in human and animal populations at risk and thus a systematic review was made of PubMed, Science Direct, Scielo and Scirus databases. Mycobacteria are classified into the Mycobacterium tuberculosis complex and non-tuberculous mycobacteria; the Mycobacterium avium complex represents the most important part of the latter because it is primarily responsible for mycobacterial infection in wild birds and is a potential pathogen for mammals, especially for immunocompromised patients. The clinical signs in birds are variable as it is a chronic and debilitating disease, involving emaciated carcasses, white nodules in different organs and microscopically it presents granulomatosous multifocal inflammation. Diagnosis begins by suspicion based on clinical signs and finishes with microbiological confirmation. New diagnostic techniques include testing with DNA-RNA probes. No effective treatment is currently available and chemoprophylaxis on suspicion of infection is not recommended at the start; these factors increase the potential risk of mycobacteriosis becoming one of the most frequently documented zoonotic diseases which is difficult to treat in birds and humans. Recent concern regarding mycobacterial infection lies in the increased frequency of these opportunistic infections occurring in immunocompromised individuals and these infections' potential impact on bird conservation, this being increased by greater contact between humans and wild and captive birds.

La micobacteriosis aviar es de importancia para la salud animal y humana. El objetivo de esta revisión fue reportar el papel de las aves en la diseminación de la micobacteriosis aviar en poblaciones vulnerables. Se realizó una revisión sistemática en las bases de datos PubMed, Science Direct, Scielo and Scirus. Las aves silvestres juegan un papel importante en la ecología y movimiento de micobacterias. Estas se clasifican en el Complejo Mycobacterium tuberculosis y las micobacterias no tuberculosas, dentro de este último grupo se destaca el Complejo Mycobacterium avium , principal responsable de micobacteriosis en aves silvestres y patógeno potencial para los mamíferos principalmente pacientes inmunosuprimidos. Los signos clínicos son variables, siendo una enfermedad debilitante y crónica, e involucra carcasas emaciadas, nódulos blanquecinos en diferentes órganos, microscópicamente presenta inflamaciones granulomatosas multifocales. El diagnóstico inicia por la sospecha basada en los síntomas clínicos y termina con la confirmación microbiológica. Adicionalmente, las nuevas técnicas diagnósticas incluyen pruebas con sondas de ADN-ARN. Actualmente, no existe un tratamiento efectivo y no se recomienda iniciar quimioprofilaxis; estos factores incrementan el riesgo potencial para convertir la micobacteriosis aviar en una enfermedad zoonótica más frecuente de lo documentado y de difícil tratamiento en aves y humanos. La reciente preocupación de las infecciones micobacterianas, radica en el aumento de la frecuencia de estas infecciones oportunistas en personas inmunocomprometidas y el impacto potencial de estas infecciones sobre la conservación de las especies de aves, favorecido por el mayor contacto entre humanos y aves tanto silvestres como cautivas.

An outbreak of avian mycobacteriosis caused by Mycobacterium intracellulare in little blue penguins (Eudyptula minor).

Mycobacterium intracellulare (MIT) was diagnosed postmortem by culture and supporting histopathology in seven birds from a flock of little blue penguins (Eudyptula minor) at the Henry Doorly Zoo (HDZ). These birds represented 20% of the deaths in the population over a 4 yr period. Clinical signs in affected birds included severe respiratory distress characterized by open-mouth breathing with chronic debilitation. On exam, plaques were noted in the larynx, trachea, and soft tissue of the caudal oropharynx. Index cases were identified on necropsy in two birds on loan to another institution in 2003. Following a case confirmed antemortem at the HDZ, a three-drug protocol of rifampin (15 mg/kg p.o. s.i.d.), ethambutol (15 mg/kg p.o. s.i.d.), and clarithromycin (10 mg/kg p.o. s.i.d.) was started on this bird in 2004 and extended to the entire flock in 2005. Gastric wash, fecal samples, and throat plaques were obtained antemortem on five birds within the flock, selected because of the presence of oral plaques, and tested by culture followed by a polymerase chain reaction assay. MIT was detected in gastric washes from four birds and in throat plaques from all five. Three more birds died during treatment. After the seventh bird died, antimicrobial susceptibility testing performed in July 2007 indicated that the MIT was now resistant to most antibiotics tested, including rifampin and ethambutol. The treatment regimen was changed to minocycline (10 mg/kg p.o. b.i.d.) and clarithromycin (10 mg/kg p.o. s.i.d.). Oral plaques were not seen on monthly rechecks of the flock through November 2008. The proposed mechanism of transmission is exposure to wild birds but the source has not been determined. These cases of avian mycobacteriosis caused by MIT are the first known cases reported in little blue penguins.

Investigation of characteristics and factors associated with avian mycobacteriosis in zoo birds.

The objective of the current study was to identify factors associated with avian mycobacteriosis in zoo birds. Inventory data, population health records, and necropsy data from eligible birds in the Zoological Society of San Diego's (ZSSD) collection from 1991-2005 (n = 13,976) were used to describe disease incidence, prevalence, and postmortem findings. A matched case-control study was then conducted to identify factors describing demographic, temporal, and enclosure characteristics, along with move and exposure histories. Cases (disease-positive birds; n = 167) were matched in a 17 ratio with controls (disease-negative birds; n = 1169) of similar age and taxonomic grouping. Potential risk factors were evaluated using univariate and multivariable conditional logistic regression. Disease prevalence and incidence were estimated for the study period at 1.2% and 3 cases/(1,000 bird-years at risk), respectively. Lesion characteristics and order prevalence are described. In the multivariable model, case birds were more likely to have been previously housed with a bird with mycobacterial disease involving the intestinal tract (odds ratio [OR] = 5.6, P < 0.01) or involving only nonintestinal sites (OR = 2.0, P < 0.01). Cases were more likely to have been imported into the collection than hatched at the ZSSD (OR = 4.2, P < 0.01). Cases were moved among ZSSD enclosures more than controls (OR = 1.1 for each additional move, P < 0.01). Findings will help guide future management of this disease for zoo bird populations.

Mycobacteriosis in companion psittacine birds: a review.

Mycobacteriosis has long been recognized as a disease of companion psittacine birds. In this review, the signalment, clinical signs of disease, and diagnosis of mycobacteriosis in psittacine birds are presented. Although treatment of birds with mycobacteriosis is controversial, therapeutic protocols for use in psittacine birds have been developed based on protocols used in humans. Results of recent studies indicate that mycobacteriosis in psittacine birds is unlikely to represent a significant health risk for humans. However, the potential for zoonotic disease must be considered, especially if persons who are immunocompromised are in contact with an infected bird.

Concurrent West Nile virus and mycobacterium avium infection in a black-necked swan (Cygnus melanocoryphus).

An adult male black-necked swan (Cygnus melanocoryphus) was evaluated for a routine physical examination and West Nile virus vaccination. Nine days later, the swan was hospitalized for weakness, dehydration, tremors, and leukocytosis. Gradual clinical improvement was seen over a 2-wk course of supportive care. However, the animal became acutely weak and was found dead. Histopathology revealed severe granulomatous pneumonia and air sacculitis with dissemination to the liver, spleen, intestine, and coelom. Mycobacterial infection was confirmed by identification of acid-fast bacilli within tissue sections and by polymerase chain reaction. Concurrent West Nile virus infection was identified in sections of brain by using immunohistochemistry.

Bird flu, influenza and 1918: the case for mutant Avian tuberculosis.

Influenza is Italian for "influence", Latin: influentia. It used to be thought that the disease was caused by a bad influence from the heavens. Influenza was called a virus long, long before it was proven to be one. In 2005, an article in the New England Journal of Medicine estimated that a recurrence of the 1918 influenza epidemic could kill between 180 million and 360 million people worldwide. A large part of the current bird-flu hysteria is fostered by a distrust among the lay and scientific community regarding the actual state of our knowledge regarding the bird flu or H5N1 and the killer "Influenza" Pandemic of 1918 that it is compared to. And this distrust is not completely unfounded. Traditionally, "flu" does not kill. Experts, including Peter Palese of the Mount School of Medicine in Manhattan, remind us that even in 1992, millions in China already had antibodies to H5N1, meaning that they had contracted it and that their immune system had little trouble fending it off. Dr. Andrew Noymer and Michel Garenne, UC Berkely demographers, reported in 2000 convincing statistics showing that undetected tuberculosis may have been the real killer in the 1918 flu epidemic. Aware of recent attempts to isolate the "Influenza virus" on human cadavers and their specimens, Noymer and Garenne summed that: "Frustratingly, these findings have not answered the question why the 1918 virus was so virulent, nor do they offer an explanation for the unusual age profile of deaths". Bird flu would certainly be diagnosed in the hospital today as Acute Respiratory Distress Syndrome (ARDS). Roger and others favor suspecting tuberculosis in all cases of acute respiratory failure of unknown origin. By 1918, it could be said, in so far as tuberculosis was concerned, that the world was a supersaturated sponge ready to ignite and that among its most vulnerable parts was the very Midwest where the 1918 unknown pandemic began. It is theorized that the lethal pig epidemic that began in Kansas just prior to the first human outbreaks was a disease of avian and human tuberculosis genetically combined through mycobacteriophage interchange, with the pig, susceptible to both, as its involuntary living culture medium. What are the implications of mistaking a virus such as Influenza A for what mycobacterial disease is actually causing? They would be disastrous, with useless treatment and preventative stockpiles. The obvious need for further investigation is presently imminent and pressing.

Outbreak of avian mycobacteriosis in a flock of two-year-old domestic pigeons (Columba livia f. domestica).

This report describes an outbreak of avian mycobacteriosis in a flock of 100 two-yr-old pigeons. Over a 6-mo period, the sick pigeons showed cachexia followed by death. In Columbiformes classic tubercles rarely develop, but in these affected pigeons granulomatous nodular lesions of various sizes, containing numerous acid-fast bacilli, were found in the internal organs. The lesions were observed in the liver, spleen, intestine, bone marrow, ovary, and oviduct. Despite their breeding age, atrophy was also found in the ovary and oviduct. Microorganisms belonging to Mycobacterium avium complex were identified in the affected tissues by polymerase chain reaction.

T-cell responses to Mycobacterium avium PPD antigens in gastro-intestinal helminth co-infected chickens in Central Ethiopia.

A cross-sectional study was conducted on extensively reared chickens of three selected agro-climatic zones in Central Ethiopia to examine the predisposing effect of gastro-intestinal helminthes to intestinal Mycobacterium avium when it occurs as co-infection. This was done through a Lymphocyte Stimulation Test (LST) using avian PPD on peripheral blood mononuclear cells obtained from the blood of chickens and gross examination of digestive tract for the presence of helminth parasites. Data were analyzed using the statistical softwares SAS (1994) and Intercooled STATA version 6. Fourteen (14.7%) out of the 95 examined chickens were positive in in vitro LST showing stimulation index (SI) > or = 2. There was a significant (chi2 = 9.93, P < 0.01) difference in prevalence of M. avium by altitude: highest in chickens from lowland (27.8%) areas, followed by 13.3% in chickens from mid altitude and none was reacted to LST from highland region. A significant relationship (chi2 = 9.58, P < 0.01) in cestode co-infection with M. avium was found. There was no significant (chi2 = 1.66, P > 0.05) relationship in nematode co-infection with M. avium.