Table 2.
Organisms of Interest Found in Core (178 Cases, 178 Controls) and Subset (98 Cases, 98 Controls) Group Stool Specimens
| Agent (Detection Methodology) | No. (%) of Positive Results | Unadjusted OR (95% CI) or P | Adjusteda OR (95% CI) | |
|---|---|---|---|---|
| Cases | Controls | |||
| Viruses (core group) | ||||
| Norovirus GI (PCR) | 4 (2.2) | 0 (0) | 0.13b | NA |
| Norovirus GII (PCR) | 30 (16.9) | 8 (4.5) | 4.7 (1.9–11.3) | 4.7 (2.2–10.1) |
| Norovirus GI and/or GII (PCR) | 33 (18.5) | 8 (4.5) | 5.2 (2.2–12.4) | 5.3 (2.5–11.3) |
| HBoVs 2, 3, and 4 (PCR) | 22 (12.4) | 14 (7.9) | 1.6 (0.8–3.2) | 1.7 (0.8–3.6) |
| Pan-astrovirus (PCR) | 6 (3.3)c | 1 (0.5) | 6.0 (0.7–50.1) | 6.8 (0.9–51.2) |
| Adenovirus (EIA) | 7 (3.9) | 2 (1.1) | 3.5 (0.7–16.9) | 3.5 (0.8–16.1) |
| Rotavirus (EIA) | 73 (41.0) | 1 (0.6) | <0.001b | NA |
| MW and STL PyV (subset group) | ||||
| MW PyV (PCR) | 10 (10.2) | 10 (10.2) | 1 (0.4–2.5) | 1.1 (0.4–3.0) |
| STL PyV (PCR) | 0 (0) | 1 (1.0) | 1.0b | NA |
| Bacterial pathogens (core group) | ||||
| Any bacterial pathogen | 21 (11.8) | NAd | NAd | NAd |
| Campylobacter (culture) | 4 (2.2)e | NAd | NAd | NAd |
| Salmonella (culture) | 8 (4.5)f | NAd | NAd | NAd |
| Shigella (culture) | 2 (1.1)g | NAd | NAd | NAd |
| E coli O157:H7h (culture) | 5 (2.8) | NAd | NAd | NAd |
| Non-O157:H7i STEC (EIA and culture) | 3 (1.7)j,k | NAd | NAd | NAd |
| STEC (EIAl) | 7 (3.9) | 0 (0) | 0.02c | NA |
| EAggEC (PCR) | 7 (3.9) | 2 (1.1) | 3.5 (0.7–16.9) | 4.3 (1.0–18.8) |
| C difficile (cytotoxicity) | 11 (6.2) | 13 (7.3) | 0.8 (0.3–2.0) | 0.7 (0.3–1.8) |
| Parasites (core group) | ||||
| Any parasite (microscopy)m | 1 (0.6) | 7 (4.0) | 0.1 (0.0–1.2) | 0.2 (0.0–1.3) |
Abbreviations: CI, confidence interval; EAggEC, enteroaggregative E coli; EIA, enzyme immunoassay; HBoV, human bocavirus; MW, Malawi; OR, odds ratio; PCR, polymerase chain reaction; PyV, polyomavirus; STEC, Shiga toxin-producing E coli; STL, St Louis.
Adjusted for mean income according to zip code and race/ethnicity.
For organisms for which ≤ 1 subject’s specimen tested positive and OR estimates were unstable, we present P values from an exact version of the McNemar test rather than ORs and CIs.
All astroviruses were classic, except for 1 case stool that contained Virginia 2 clade and Campylobacter. Restricting the analysis to only the classic astroviruses did not alter the calculated OR, adjusted OR, or 95% CIs meaningfully.
Not applicable because controls were not tested for this agent.
Three of these cases were infected with Campylobacter jejuni.
Includes Salmonella enterica subsp enterica serovar Typhimurium (3), S enterica subsp enterica serovar Heidelberg (2), S enterica subsp enterica serovar Brandenburg, S enterica subsp enterica serovar Newport, and Salmonella serotype I 4,5,12:i:- (1 each).
Both Shigella sonnei.
As identified on sorbitol MacConkey agar; the broth culture of 1 subject tested negative for Stx (EIA).
Isolates from broth cultures that tested positive for Stx (EIA).
One case-subject was infected with STEC O111:nonmotile and S enterica subsp enterica serovar Brandenburg.
E coli isolates belonged to serotypes O111:nonmotile, O121:nonmotile, and O177:nonmotile (1 each).
Defined as subjects whose broth cultures tested positive for Shiga toxin (Stx) (EIA) and from which a non-O157:H7 or an O157:H7 STEC was recovered but does not include the additional case subject whose stool contained STEC O157:H7, as identified on sorbitol MacConkey agar, but whose toxin assay result was negative.
Cryptosporidia spp (1 case and 4 control subjects) and Entamoeba coli, Blastocystis hominis, and Endolimax nana (1 control subject each).