At a glance
In 2020, health departments reported 226 cases of botulism to ÐÇ¿ÕÓéÀÖ¹ÙÍø. Of those, 202 cases were laboratory-confirmed and 24 were probable. The cases were of the following types: 159 (70%) infant, 55 (24%) wound, 9 (4%) foodborne, and 3 (1%) other.
Infant botulism cases
Health departments reported 159 laboratory-confirmed cases of infant botulism (Table 1). Cases were reported from 32 states, with California (42 cases, 26%) and Pennsylvania (23, 14%) reporting the most. The toxin types were A (64, 40%), B (93, 58%), Bf (1, <1%), and F (1, <1%).
Type Bf infant botulism is very uncommon; only 18 U.S. cases have been previously reported (7 from California, 7 Texas, 1 Maryland, 1 New Jersey, 1 New Mexico, 1 New York). The type Bf case in 2020 was identified in Texas. Toxin type Bf indicates a bivalent strain, which means one strain can produce two types of toxin (in this case Type B and Type F). The capital letter indicates the most abundant toxin type.
The median age of infants was 4 months; 79 (50%) were male and 80 (50%) were female. No deaths were reported.
Wound botulism cases
Health departments reported 55 cases of wound botulism, including 32 laboratory-confirmed and 23 probable (Table 1).
The 32 cases of laboratory-confirmed wound botulism were reported from 7 states: California (23 cases, 72%), Texas (5, 16%), Arizona (1, 3%), New Jersey (1, 3%), New Mexico (1, 3%), and Pennsylvania (1, 3%) (Table 1).
Among the 24 cases with exposure information available, 22 (92%) cases reported injection drug use, and of those, 12 (55%) reported using black tar heroin. Two (6%) cases were linked to injuries; one from a motor vehicle accident and one from a fall at a construction site.
The median age of patients was 47 years (range: 28–63); 26 (81%) were male. Four (4, 13%) deaths were reported. The toxin types were A (22, 69%), B (8, 25%), and type AB (2, 6%). Toxin type AB indicates that both toxin types A and B were detected in the patients' clinical samples.
The 23 cases of probable wound botulism were reported from California (18, 78%), Texas (4, 17%), and Oklahoma (1, 4%). All occurred in persons who injected drugs; 11 (79%) reported black tar heroin use. The median age of cases was 43 years (range: 27–67); 19 (83%) were male and 4 (17%) were female. No deaths were reported.
Seven (7) cases (2 lab-confirmed, 5 probable) were part of an outbreak reported in Texas in December 2020. All 7 patients injected black tar heroin.
Foodborne botulism cases
Health departments reported 9 cases of foodborne botulism, all of which were laboratory-confirmed (Table 1). Six (67%) were type A, 2 (22%) type B, and 1 (11%) type F.
The 9 cases of laboratory-confirmed foodborne botulism were reported from 6 states; Colorado reported the most (3 cases, 33%). Confirmed or suspected foods linked to cases are described in Table 2. Four confirmed cases were associated with outbreaks:
- Idaho reported a type A outbreak of two cases linked to home-canned asparagus.
- Colorado and Arizona each reported one type A case linked to home-canned green chili peppers and onions. Both cases first became ill in Colorado.
The median age of patients with laboratory-confirmed foodborne botulism was 62 years (range: 41–73); 4 (44%) were male and 5 (56%) were female. One death was reported.
Other cases of botulism
Health departments reported 3 cases of laboratory-confirmed botulism of unknown or other etiology from 3 states. The median age of cases was 40 years (range: 33–55); 1 case (33%) was male and the remainder (2, 67%) were female. Toxin types were type A (1, 33%), B (1, 33%), and F (1, 33%). No deaths were reported.
One case reported from Minnesota was suspected to be due to adult intestinal colonization, a rare form of botulism thought to have a similar mechanism to infant botulism. No definitive route of transmission was identified for the other two cases, who did not report consuming a suspect food, have any wounds, recent history of botulinum toxin injections, or have any known risk factors for adult intestinal colonization.
Tables
| Transmission Category | Cases | Median Age (range) |
Deaths | Sex, n (%) | Toxin Type, n (%) | Outbreaks* |
|---|---|---|---|---|---|---|
| Infant | 159 | 4 months (9 days – 12 months) | 0 | Male: 79 (50); Female: 80 (50) |
A: 64 (40), B: 93 (58), Bf: 1 (<1), F: 1 (<1) |
0 |
| Wound | 32 | 47 (28–63) years | 4 | Male: 26 (81); Female: 6 (19) |
A: 22 (69), B: 8 (25), AB: 2 (6) |
1 |
| Foodborne | 9 | 62 (41–73) years | 1 | Male: 4 (44); Female: 5 (56) |
A: 6 (67), B: 2 (22), F: 1 (11) |
2 |
| Other |
3 | 40 (33–55) years | 0 | Male: 1 (33); Female: 2 (67) |
A: 1 (33), B: 1 (33), F: 1 (33) |
0 |
| Transmission Category | Cases | Median Age (range) |
Deaths | Sex, n (%) | Toxin Type, n (%) | Outbreaks* |
|---|---|---|---|---|---|---|
| Wound¶ | 23 | 43 (27–67) years | 0 | Male: 19 (83); Female: 4 (17) |
Not applicable | 1 |
*Outbreak defined as two or more cases resulting from a common exposure.
¶Probable wound botulism is defined as a clinically compatible case with no suspected exposure to contaminated food and with a history in the 2 weeks before illness began of either a fresh contaminated wound or injection drug use.
| Month | State | Confirmed or Suspected Food | Toxin Type | Cases |
|---|---|---|---|---|
| April | Arkansas | Expired canned food, unspecified | A | 1 |
| May | Idaho | Home-canned asparagus | A | 2 |
| July | Virginia | Home-canned food, unspecified | B | 1 |
| August | Colorado | Unknown | A | 1 |
| August | Iowa | Home-canned peaches | F | 1 |
| September | Colorado | Unknown | B | 1 |
| October | Arizona | Home-canned green chili peppers with onions* | A | 1 |
| October | Colorado | Home-canned green chili peppers with onions* | A | 1 |
*Foods followed by an asterisk were confirmed as the source by detection of toxin in food. In foods without an asterisk, toxin was not detected, or food item was not available for testing; food vehicle was suspected based on clinical history, epidemiologic evidence, or reported method of preparation or storage.