Table 4. Associations between Corynebacterium diphtheriae carriage and potential risk factors, Vietnam*.
| Risk factor | Carriage, no. (%) |
p value† | |
|---|---|---|---|
| Total | Tested | ||
| Age group, y | |||
| <5 | 12 (4.5) | 257 (95.5) | <0.01 |
| 6‒17 | 10 (3.1) | 314 (96.9) | |
| 18‒40 | 5 (1.0) | 518 (99.0) | |
| 41‒55 |
0 |
102 (100.0) |
|
| Sex | |||
| M | 10 (1.6) | 605 (98.4) | 0.198 |
| F |
17 (2.8) |
584 (97.2) |
|
| DTP1 <10 years | |||
| 0 doses | 5 (4.5) | 107 (95.5) | >0.99 |
|
>1 dose |
16 (4.5) |
336 (95.5) |
|
| DTP3 <10 years | |||
| <3 doses | 5 (4.3) | 111 (95.7) | >0.99 |
|
>3 doses |
16 (4.6) |
332 (95.4) |
|
| Diphtheria antibody, IU/mL | |||
| <0.1 | 11 (1.7) | 630 (98.3) | 0.24 |
|
>0.1 |
16 (2.8) |
559 (97.2) |
|
| School | |||
| Not attended | 17 (1.8) | 906 (98.2) | 0.12 |
| Attended |
6 (2.1) |
283 (97.9) |
|
| Dormitory | |||
| Not staying | 23 (2.2) | 1,035 (97.8) | 0.77 |
| Staying |
4 (2.5) |
154 (97.5) |
|
| Sharing bed | |||
| Yes | 4 (2.7) | 143 (97.3) | 0.56 |
| No |
23 (2.2) |
1,037 (97.8) |
|
| Household size, no, persons | |||
| <4 | 13 (2.2) | 585 (97.8) | >0.99 |
| >4 |
14 (2.3) |
604 (97.7) |
|
| Bathing, times/day | |||
| <1 | 0 | 72 (100.0) | 0.40 |
|
>1 |
27 (2.4) |
1,117 (97.6) |
|
| Handwashing, times/day | |||
| <3 | 4 (1.6) | 247 (98.4) | 0.11 |
|
>3 |
18 (3.9) |
445 (96.1) |
|
| Livestock or pet animal | |||
| No | 24 (2.7) | 866 (97.3) | 0.08 |
| Yes |
3 (0.9) |
323 (99.1) |
|
| Category | Positive | Negative | p value by t-test |
| MUAC, cm, mean (SD) | 15.0 (1.77) | 14.8 (1.33) | 0.16 |
| Age, y, mean (SD) | 7 (9.7) | 20 (14.3) | <0.01 |
| log-transformed IgG level, mean (SD) | ‒1.4 (2.1) | ‒2.2 (1.2) | <0.01 |
*DTP, diphtheria‒tetanus‒pertussis; MUAC, mid-upper arm circumference. †By Fisher exact test except as indicated.