Is PCR the Next Reference Standard for the Diagnosis of Schistosoma in Stool? A Comparison with Microscopy in Senegal and Kenya

Details

• Alternative Title:
  PLoS Negl Trop Dis
• Personal Author:
  Meurs, Lynn ; Brienen, Eric ; Mbow, Moustapha ; Ochola, Elizabeth A. ; Mboup, Souleymane ; Karanja, Diana M. S. ; Secor, W. Evan ; Polman, Katja ; van Lieshout, Lisette
• Description:
  Background
  
  The current reference test for the detection of S. mansoni in endemic areas is stool microscopy based on one or more Kato-Katz stool smears. However, stool microscopy has several shortcomings that greatly affect the efficacy of current schistosomiasis control programs. A highly specific multiplex real-time polymerase chain reaction (PCR) targeting the Schistosoma internal transcriber-spacer-2 sequence (ITS2) was developed by our group a few years ago, but so far this PCR has been applied mostly on urine samples. Here, we performed more in-depth evaluation of the ITS2 PCR as an alternative method to standard microscopy for the detection and quantification of Schistosoma spp. in stool samples.
  
  Methodology/Principal findings
  
  Microscopy and PCR were performed in a Senegalese community (n = 197) in an area with high S. mansoni transmission and co-occurrence of S. haematobium, and in Kenyan schoolchildren (n = 760) from an area with comparatively low S. mansoni transmission. Despite the differences in Schistosoma endemicity the PCR performed very similarly in both areas; 13–15% more infections were detected by PCR when comparing to microscopy of a single stool sample. Even when 2–3 stool samples were used for microscopy, PCR on one stool sample detected more infections, especially in people with light-intensity infections and in children from low-risk schools. The low prevalence of soil-transmitted helminthiasis in both populations was confirmed by an additional multiplex PCR.
  
  Conclusions/Significance
  
  The ITS2-based PCR was more sensitive than standard microscopy in detecting Schistosoma spp. This would be particularly useful for S. mansoni detection in low transmission areas, and post-control settings, and as such improve schistosomiasis control programs, epidemiological research, and quality control of microscopy. Moreover, it can be complemented with other (multiplex real-time) PCRs to detect a wider range of helminths and thus enhance effectiveness of current integrated control and elimination strategies for neglected tropical diseases.
  
  
• Subjects:
  Animals Feces Humans Microscopy Polymerase Chain Reaction Reference Standards Schistosoma Mansoni Schistosomiasis Mansoni
• Source:
  PLoS Negl Trop Dis. 9(7).
• Pubmed ID:
  26217948
• Pubmed Central ID:
  PMC4517772
• Document Type:
  Journal Article
• Place as Subject:
  Kenya ; Senegal
• Volume:
  9
• Issue:
  7
• Collection(s):
  CDC Public Access
• Main Document Checksum:
  urn:sha256:829e0a9f3e1dba8e5c11d3822a2cdf538db7263b619f8d35638bbed34ea88fbb
• Download URL:
  https://stacks.cdc.gov/view/cdc/32719/cdc_32719_DS1.pdf
• File Type:
  [PDF - 651.27 KB ]