What to know
- In 2020, 602 confirmed malaria cases were reported to the CDC National Malaria Surveillance System, the lowest number since 1972.
- This reduction was likely due to interruption of foreign travel because of the COVID-19 pandemic.
- There were 6 deaths reported in 2020, a case fatality rate of 1.0, the highest during 2007 – 2022.
- Almost all cases reported in 2020 were travel associated (imported).
Key findings
- In 2020, of the 602 confirmed cases, 390 (64.8%) occurred among U.S. civilians, 14 (2.3%) among U.S. military members, 87 (14.5%) among non-U.S. residents, and 111 (18.4%) had an unknown residence status.
- P. falciparum species causes the most severe disease and death, and 389 cases (77.2%) with a species determination in 2020 were P. falciparum, followed by P. vivax (61 cases, 12.1%) and P. ovale (31 cases, 6.2%). Compared to 2019, in 2020 the proportion of P. vivax and P. ovale species was higher, possibly because as global travel was limited, the proportion of illnesses due to relapses was higher.
- Case classification
- Travel associated (imported): 578 (96.0%)
- From a blood exposure (induced) 2 (<1.0%) cases
- The source of malaria could not be determined after an investigation for 1 (<1%) case (cryptic). For this isolated case, the source of malaria could not be determined after an investigation; the patient reported travel to an endemic country more than two years prior to illness onset.
- Lost to follow-up: 21 (3.5%) cases whose classification was unable to be determined
- Among 578 imported cases, the region of travel was reported for 542 cases (93.8%). Of these, Africa was the most common region of travel, reported by 490 cases (90.4%), followed by Asia 35 cases (6.5%) and South America 9 cases (1.6%); less than 1% of cases reported travel in Central America (1 case), the Caribbean (2 cases), Oceania (4 cases), and the Middle East (1 case). Among the 490 cases reporting travel in Africa, 280 (57.1%) traveled in West Africa.
- Despite the decrease in overall cases, six people died from malaria in 2020, resulting in a case fatality rate of 1.0, the highest fatality rate between 2007 – 2022 (Malaria Deaths and Case Fatality Rate, 2007 - 2022). In 2020, half the fatal cases were diagnosed with P. falciparum, and half had an undetermined species. Three people who died were aged 40 to 49 years old, two were 50 to 59 years old, and one was 65 years or older. Three people who died were male and three were female, and five had traveled in Africa, while the travel information for one person who died was unknown. One each had traveled for business, as a missionary, or to visit friends and relatives, and three traveled for unknown reasons. None were reported to have taken medication during travel to prevent malaria.
- Twelve jurisdictions were in the top quartile for having the most malaria cases in 2020.
Results
Number of malaria cases by demographics, region of acquisition, and primary reason for travel, by patient resident status — United States, 2020
| Demographic Table, 2020 | |||||||||||||||||||
| U.S. Military | U.S. Civilian | Non-U.S. | Not recorded | Total | |||||||||||||||
| Demographics | No. | (%)1 | (%)2 | No. | (%)1 | (%)2 | No. | (%)1 | (%)2 | No. | (%)1 | (%)2 | No. | (%)1 | (%)2 | ||||
| Total | 14 | 2.3 | — | 390 | 64.8 | — | 87 | 14.5 | — | 111 | 18.4 | — | 602 | 100 | — | ||||
| Male sex | 12 | 85.7 | — | 247 | 63.3 | — | 56 | 64.4 | — | 73 | 65.8 | — | 388 | 64.5 | — | ||||
| Female sex | 2 | 14.3 | — | 143 | 36.7 | — | 31 | 35.6 | — | 38 | 34.2 | — | 214 | 35.5 | — | ||||
| Age less than 18 years | 0 | 0.0 | — | 29 | 7.4 | — | 30 | 34.5 | — | 12 | 10.8 | 10.8 | 71 | 11.8 | — | ||||
| Age 18 – 64 years | 14 | 100.0 | — | 327 | 83.8 | — | 54 | 62.1 | — | 89 | 80.2 | 80.2 | 484 | 80.4 | — | ||||
| Age 65 years and older | 0 | 0.0 | — | 34 | 8.7 | — | 3 | 3.4 | — | 10 | 9.0 | 9.0 | 47 | 7.8 | — | ||||
| Not Hispanic or Latino | 7 | 50.0 | 100.0 | 302 | 77.4 | 97.7 | 60 | 69.0 | 95.2 | 90 | 81.0 | 100.0 | 459 | 76.2 | 97.9 | ||||
| Hispanic or Latino | 0 | 0.0 | 0.0 | 7 | 1.8 | 2.3 | 3 | 3.4 | 4.8 | 0 | 0.0 | 0.0 | 10 | 1.7 | 2.1 | ||||
| Unknown | 7 | 50.0 | — | 81 | 20.8 | — | 24 | 27.6 | — | 21 | 18.9 | — | 133 | 22.1 | — | ||||
| Race Asian | 1 | 7.1 | 7.7 | 8 | 2.1 | 2.2 | 9 | 10.3 | 11.8 | 5 | 4.5 | 5.3 | 23 | 3.8 | 4.2 | ||||
| Race Black or African American | 3 | 21.4 | 23.1 | 264 | 67.7 | 72.7 | 49 | 56.3 | 64.5 | 70 | 63.1 | 73.7 | 386 | 64.1 | 70.2 | ||||
| Race White | 9 | 64.3 | 69.2 | 61 | 15.6 | 16.8 | 12 | 13.8 | 15.8 | 10 | 9.0 | 10.5 | 92 | 15.3 | 16.7 | ||||
| Race Other | 1 | 0.0 | 0.0 | 27 | 7.7 | 8.3 | 11 | 12.6 | 7.9 | 10 | 9.0 | 10.5 | 49 | 8.1 | 8.9 | ||||
| Race Unknown | 0 | 0.0 | — | 30 | 7.7 | — | 6 | 6.9 | — | 16 | 14.4 | — | 52 | 8.6 | — | ||||
| Region of acquisition3 | No. | (%)1 | (%)2 | No. | (%)1 | (%)2 | No. | (%)1 | (%)2 | No. | (%)1 | (%)2 | No. | (%)1 | (%)2 | ||||
| Total | 14 | 2.4 | — | 383 | 66.3 | — | 86 | 14.9 | — | 95 | 16.4 | — | 578 | 100 | — | ||||
| Africa | 5 | 35.7 | — | 344 | 89.8 | 94.0 | 69 | 80.2 | 82.1 | 72 | 75.8 | 92.3 | 490 | 84.8 | 90.4 | ||||
| Asia | 9 | 64.3 | — | 11 | 2.9 | 3.0 | 11 | 12.8 | 13.1 | 4 | 4.2 | 5.1 | 35 | 6.1 | 6.5 | ||||
| South America | 0 | 0.0 | — | 5 | 1.3 | 1.4 | 3 | 3.5 | 3.6 | 1 | 1.1 | 1.3 | 9 | 1.6 | 1.7 | ||||
| Central America / Caribbean | 0 | 0.0 | — | 2 | 0.5 | 0.5 | 1 | 1.2 | 1.2 | 0 | 0.0 | 0.0 | 3 | 0.5 | 0.6 | ||||
| Oceania | 0 | 0.0 | — | 4 | 1.0 | 1.1 | 0 | 0.0 | 0.0 | 0 | 0.0 | 0.0 | 4 | 0.7 | 0.7 | ||||
| Middle East | 0 | 0.0 | — | 0 | 0.0 | 0.0 | 0 | 0.0 | 0.0 | 1 | 1.1 | 1.3 | 1 | 0.2 | 0.2 | ||||
| Unknown | 0 | 0.0 | — | 17 | 4.4 | — | 2 | 2.3 | — | 17 | 17.9 | — | 36 | 6.2 | — | ||||
| Africa, West | 3 | 21.4 | — | 208 | 54.3 | 56.8 | 26 | 30.2 | 31.0 | 43 | 45.3 | 55.1 | 280 | 48.4 | 51.7 | ||||
| Primary reason for travel3 | No. | (%)1 | (%)2 | No. | (%)1 | (%)2 | No. | (%)1 | (%)2 | No. | (%)1 | (%)2 | No. | (%)1 | (%)2 | ||||
| Total | 14 | 2.4 | — | 383 | 66.3 | 86 | 14.9 | — | 95 | 16.4 | — | 578 | 100 | — | |||||
| Visiting friends and relatives | 0 | 0.0 | — | 211 | 55.1 | 76.2 | 11 | 12.8 | 16.2 | 16 | 16.8 | 80.0 | 238 | 41.2 | 62.8 | ||||
| Tourist | 0 | 0.0 | — | 15 | 3.9 | 5.4 | 1 | 1.2 | 1.5 | 1 | 1.1 | 5.0 | 17 | 2.9 | 4.5 | ||||
| Missionary or dependent | 0 | 0.0 | — | 19 | 5.0 | 6.9 | 1 | 1.2 | 1.5 | 0 | 0.0 | 0.0 | 20 | 3.5 | 5.3 | ||||
| Business | 0 | 0.0 | — | 24 | 6.3 | 8.7 | 0 | 0.0 | 0.0 | 1 | 1.1 | 5.0 | 25 | 4.3 | 6.6 | ||||
| Student or teacher | 0 | 0.0 | — | 3 | 0.8 | 1.1 | 4 | 4.7 | 5.9 | 1 | 1.1 | 5.0 | 8 | 1.4 | 2.1 | ||||
| Airline/ship crew | 0 | 0.0 | — | 1 | 0.3 | 0.4 | 1 | 1.2 | 1.5 | 0 | 0.0 | 0.0 | 2 | 0.3 | 0.5 | ||||
| Peace Corps | 0 | 0.0 | — | 3 | 0.8 | 1.1 | 0 | 0.0 | 0.0 | 0 | 0.0 | 0.0 | 3 | 0.5 | 0.8 | ||||
| Refugee or immigrant | 0 | 0.0 | — | 0 | 0.0 | 0.0 | 49 | 57.0 | 72.1 | 0 | 0.0 | 0.0 | 49 | 8.5 | 12.9 | ||||
| Military deployment | 14 | 100.0 | — | 0 | 0.0 | 0.0 | 0 | 0.0 | 0.0 | 0 | 0.0 | 0.0 | 14 | 2.4 | 3.7 | ||||
| Other | 0 | 0.0 | — | 1 | 0.3 | 0.4 | 1 | 1.2 | 1.5 | 1 | 1.1 | 5.0 | 3 | 0.5 | 0.8 | ||||
| Unknown | 0 | 0.0 | — | 106 | 27.7 | — | 18 | 20.9 | — | 75 | 78.9 | — | 199 | 34.4 | — | ||||
| 1 Percentage calculated among all subjects | |||||||||||||||||||
| 2 Percentage calculated among subjects with known responses | |||||||||||||||||||
| 3 Among imported cases | |||||||||||||||||||
In 2020, most people diagnosed with malaria in the United States were male, 18 – 64 years old, non-Hispanic or Latino ethnicity, and Black/African American race. Case patients predominantly traveled in Africa. More than half of all case patients traveled to or from West Africa. More than half of U.S. civilians with malaria traveled to visit friends and relatives in 2020.
Supplementary data files
Tables with case counts by species, country of acquisition, and diagnostic confirmation method (e.g., blood smear microscopy only, or polymerase chain reaction confirmed [with or without blood smear microscopy]) are available for download for year 2020.