Limits...
Comparison of individual and pooled stool samples for the assessment of intensity of Schistosoma mansoni and soil-transmitted helminth infections using the Kato-Katz technique.

Kure A, Mekonnen Z, Dana D, Bajiro M, Ayana M, Vercruysse J, Levecke B - Parasit Vectors (2015)

Bottom Line: A cross-sectional survey was conducted in 360 children aged 5-18 years from six schools in Jimma Zone (southwest Ethiopia).For this STH, pools of 10 resulted in a significant underestimation of infection intensity.In this setting, the time in the laboratory was reduced by 70 % when pools of 5 instead of individual stool samples were screened.

View Article: PubMed Central - PubMed

Affiliation: Public Health Laboratory, Southern Nations Nationalities and People's Regional State Health Bureau, Hawassa, Ethiopia. ashenafikure@gmail.com.

ABSTRACT

Background: Our group has recently provided a proof-of-principle for the examination of pooled stool samples using McMaster technique as a strategy for the rapid assessment of intensity of soil-transmitted helminth infections (STH, Ascaris lumbricoides, Trichuris trichiura and hookworm). In the present study we evaluated this pooling strategy for the assessment of intensity of both STH and Schistosoma mansoni infections using the Kato-Katz technique.

Methods: A cross-sectional survey was conducted in 360 children aged 5-18 years from six schools in Jimma Zone (southwest Ethiopia). We performed faecal egg counts (FECs) in both individual and pooled samples (pools sizes of 5, 10 and 20) to estimate the number of eggs per gram of stool (EPG) using the Kato-Katz technique. We also assessed the time to screen both individual and pooled samples.

Results: Except for hookworms, there was a significant correlation (correlation coefficient = 0.53-0.95) between the mean of individual FECs and the FECs of pooled samples for A. lumbricoides, T. trichiura and S. mansoni, regardless of the pool size. Mean FEC were 2,596 EPG, 125 EPG, 47 EPG, and 41 EPG for A. lumbricoides, T. trichiura, S. mansoni and hookworm, respectively. There was no significant difference in FECs between the examination of individual and pooled stool samples, except for hookworms. For this STH, pools of 10 resulted in a significant underestimation of infection intensity. The total time to obtain individual FECs was 65 h 5 min. For pooled FECs, this was 19 h 12 min for pools of 5, 14 h 39 min for pools of 10 and 12 h 42 min for pools of 20.

Conclusions: The results indicate that pooling of stool sample holds also promise as a rapid assessment of infections intensity for STH and S. mansoni using the Kato-Katz technique. In this setting, the time in the laboratory was reduced by 70 % when pools of 5 instead of individual stool samples were screened.

No MeSH data available.


Related in: MedlinePlus

Number of schools and stool samples for assessing infection intensity of soil-transmitted helminths and Schistosoma mansoni
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License 1 - License 2
getmorefigures.php?uid=PMC4581403&req=5

Fig1: Number of schools and stool samples for assessing infection intensity of soil-transmitted helminths and Schistosoma mansoni

Mentions: In each school, we stratified subjects according to three age groups (age 5–9 years, age 10–14 years and age 15–18 years). For each age group at least 20 subjects were randomly selected, resulting in a total of at least 60 subjects per school. The subjects were asked to provide at least 3 g of stool to examine the samples individually and to pool individual stool samples. All stool samples were individually processed by the Kato-Katz technique. Figure 1 illustrates the number of primary schools eligible, recruited, and included in the statistical analysis.Fig. 1


Comparison of individual and pooled stool samples for the assessment of intensity of Schistosoma mansoni and soil-transmitted helminth infections using the Kato-Katz technique.

Kure A, Mekonnen Z, Dana D, Bajiro M, Ayana M, Vercruysse J, Levecke B - Parasit Vectors (2015)

Number of schools and stool samples for assessing infection intensity of soil-transmitted helminths and Schistosoma mansoni
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4581403&req=5

Fig1: Number of schools and stool samples for assessing infection intensity of soil-transmitted helminths and Schistosoma mansoni
Mentions: In each school, we stratified subjects according to three age groups (age 5–9 years, age 10–14 years and age 15–18 years). For each age group at least 20 subjects were randomly selected, resulting in a total of at least 60 subjects per school. The subjects were asked to provide at least 3 g of stool to examine the samples individually and to pool individual stool samples. All stool samples were individually processed by the Kato-Katz technique. Figure 1 illustrates the number of primary schools eligible, recruited, and included in the statistical analysis.Fig. 1

Bottom Line: A cross-sectional survey was conducted in 360 children aged 5-18 years from six schools in Jimma Zone (southwest Ethiopia).For this STH, pools of 10 resulted in a significant underestimation of infection intensity.In this setting, the time in the laboratory was reduced by 70 % when pools of 5 instead of individual stool samples were screened.

View Article: PubMed Central - PubMed

Affiliation: Public Health Laboratory, Southern Nations Nationalities and People's Regional State Health Bureau, Hawassa, Ethiopia. ashenafikure@gmail.com.

ABSTRACT

Background: Our group has recently provided a proof-of-principle for the examination of pooled stool samples using McMaster technique as a strategy for the rapid assessment of intensity of soil-transmitted helminth infections (STH, Ascaris lumbricoides, Trichuris trichiura and hookworm). In the present study we evaluated this pooling strategy for the assessment of intensity of both STH and Schistosoma mansoni infections using the Kato-Katz technique.

Methods: A cross-sectional survey was conducted in 360 children aged 5-18 years from six schools in Jimma Zone (southwest Ethiopia). We performed faecal egg counts (FECs) in both individual and pooled samples (pools sizes of 5, 10 and 20) to estimate the number of eggs per gram of stool (EPG) using the Kato-Katz technique. We also assessed the time to screen both individual and pooled samples.

Results: Except for hookworms, there was a significant correlation (correlation coefficient = 0.53-0.95) between the mean of individual FECs and the FECs of pooled samples for A. lumbricoides, T. trichiura and S. mansoni, regardless of the pool size. Mean FEC were 2,596 EPG, 125 EPG, 47 EPG, and 41 EPG for A. lumbricoides, T. trichiura, S. mansoni and hookworm, respectively. There was no significant difference in FECs between the examination of individual and pooled stool samples, except for hookworms. For this STH, pools of 10 resulted in a significant underestimation of infection intensity. The total time to obtain individual FECs was 65 h 5 min. For pooled FECs, this was 19 h 12 min for pools of 5, 14 h 39 min for pools of 10 and 12 h 42 min for pools of 20.

Conclusions: The results indicate that pooling of stool sample holds also promise as a rapid assessment of infections intensity for STH and S. mansoni using the Kato-Katz technique. In this setting, the time in the laboratory was reduced by 70 % when pools of 5 instead of individual stool samples were screened.

No MeSH data available.


Related in: MedlinePlus