The Use of Moore Swabs for Isolation of Salmonella typhi from Irrigation Water in Santiago, Chile

Abstract

In Chile, a country with an exceedingly high incidence of typhoid, untreated sewage is applied directly to fields where salad vegetables are cultivated. Water used for irrigation was examined for the presence of Salmonella typhi, by making use of the sewer-swab technique. S typhi was isolated in 8 (11%) of 76 irrigation samples examined from nonindustrial, polluted water. This supports the hypothesis that crops grown with water contaminated with feces are important vehicles in the transmission of S typhi in this endemic area. Since sewage treatment plants will not be available in Santiago in the near future, emphasis is being placed on devising alternative methods of irrigation and on growing vegetables that are cooked before being eaten.

Detection of Salmonella spp. from large volumes of water by modified Moore swabs and tangential flow filtration

“…Moore swabs have previously been used to isolate Salmonella from surface (Spino 1966;Sears et al 1984) and fountain water (Escartin et al 2002), E. coli O157 from soil and field water (Ogden 2001), Campylobacter from river water (Fernandez et al 2003) and V. cholerae from sewage (Barrett et al 1980). In these cases, MS was secured in the body of water for a set duration of time, rather than pumping a specified volume of water through the swab.…”

“…Alternative filtration methods include TFF where water flows across a filter membrane; Moore swabs (MS) where rolled cotton gauze is tied and allowed to sit in a body of water for at least 24 h; and modified Moore swabs (MMS) where pieces of pipe are filled with rolled cotton gauze, which traps bacteria as water is pushed through the pipe. Previously, up to 100 l of surface water has been concentrated using TFF (Mull and Hill 2009;Gibson and Schwab 2011), and MS has been used to isolate Salmonella (Spino 1966;Sears et al 1984;Escartin et al 2002), E. coli O157 (Ogden 2001), Campylobacter (Fernandez et al 2003) and Vibrio cholerae (Barrett et al 1980). MMS has been used to isolate E. coli O157 and Salmonella (Bisha et al 2011).…”

Safety, Immunogenicity, and Transmissibility of Single-Dose Live Oral Cholera Vaccine Strain CVD l03-HgR in 24- to 59-Month-Old Indonesian Children

“…Although the US Food and Drug Administration does not regulate genetically engineered vaccines any differently than it does live vaccines prepared by nonrecombinant means such as chemical mutagenesis, there are advantages to using a live recombinant vaccine such as CVD 103-HgR that is not heavily excreted and that does not readily enter or persist in the environment. The sensitivity and utility of Moore swab environmental sampling to isolate Salmonella typhi [30,53,54] and V. choferae 0 I [29] from fecally contaminated surface waters is well-established. Moore swabs did not recover CVD 103-HgR from the environment around any of the 97 North Jakarta households sampled.…”

Prevalence ofSalmonellaExcretion in Stool: A Community Survey in 2 Sites, Guinea-Bissau and Senegal

“…Additionally, up to 25% of chronic carriers of S. Typhi report no history of disease [9]. In many developing countries, open defecation can lead to contamination of water systems, resulting in an increased risk of Salmonella transmission through the ingestion of bacteria in water used for drinking, washing, or irrigating produce [10][11][12]. Factors related to water source and storage, sanitation practices, and street food consumption have also been associated with increased risk of infection [13].…”