Tanzania: Cholera Outbreak - Jul 2023

The Ministry of Health in the United Republic of Tanzania notified the World Health Organization about a cholera outbreak in three regions, namely Arusha, Kigoma, and Mara, in July 2023. On 11 September 2023, Mara region recorded 13 suspected cases, which were subsequently laboratory-confirmed at the Tanzania National Public Health Laboratory (NPHL), followed by five confirmed cholera cases which were reported in Kigoma region on 13 September 2023. During epidemiological week 40 (ending 8 October 2023), 16 new cases were reported, including 14 in Arusha, and two in Mara region with no reported deaths. As of 8 October 2023, a total of 268 cholera cases with nine deaths (CFR= 3.3%) have been reported and Most of the cases (61.0%, n=164) were recorded in the Mara region, followed by Arusha (24.0%, n=66) and Kigoma (14.0%, n=38). (WHO, 20 Oct 2023)

On 3 October 2023, WHO was notified about a Cholera outbreak affecting three regions of Tanzania Mainland: Mara, bordering Kenya, Arusha and Kigoma. As of 28 October 2023, a total of 548 cases including 14 deaths (CFR 2.6%) were reported from eleven districts of Mara, Kigoma, Arusha, Kilimanjaro, and Singida regions. Four cases were admitted in Singida (3) and Arusha (1). Of the 72 samples tested by culture, 53 showed growth of Vibrio cholerae. Women account for 55.5% (304) of cases, and 44.7% (245) of cases are aged between 15 and 44 years. WHO, 9 Nov 2023.

Since September 5th, 2023, a cholera outbreak has been reported in 13 regions of Tanzania Mainland, including Mara, Arusha, Kilimanjaro, Kigoma, Kagera, Singida, Simiyu, Shinyanga, Tabora, Ruvuma, Dodoma, Mwanza, and Geita. A total of 1,521 cases and 34 deaths (a Case Fatality Rate of 2.3%) have been recorded. Out of these regions, the cholera outbreak has been declared over in five: Mara, Kigoma, Arusha, Kilimanjaro, and Dodoma. However, cases in Mwanza, Shinyanga, Simiyu, and Kagera regions have continued to rise, making them the most affected currently. The increasing trend indicates a risk of further spread without necessary interventions. With the upcoming El Niño and the long rains expected from March to May 2024, there is a likelihood of a rise in cases, potentially affecting more regions. This situation is exacerbated by the current outbreaks in eight regions (Kagera, Ruvuma, Simiyu, Tabora, Shinyanga, Singida, Geita, and Mwanza) with 851 active cases reported since December 23rd, 2023. Most cases (46.8%) are female, with the majority (33.8%) aged between 15 and 49 years. (IFRC, 15 Feb 2024)

The cumulative number of cases from the country since 22 January 2023 to 10 March 2024 are 2 769 and 53 deaths with a CFR= 1.9%. In week 10 of 2024, new cases decreased by 26.0% from 281 in week 09 to 208. In week 10 of 2024, new deaths increased by from one death in the previous week to three new deaths. The regions with active cases are Dar es Salaam, Dodoma, Kagera, Katavi, Manyara, Morogoro, Mwanza, Rukwa, Shinyanga, Simiyu, and Singida. (WHO, 11 Mar 2024)

Since 5 September 2023 cholera outbreaks have been reported in 20 regions (Mara, Arusha, Kilimanjaro, Kigoma, Kagera, Singida, Simiyu, Shinyanga, Tabora, Ruvuma, Mwanza, Geita, Rukwa, Dodoma, Manyara, Morogoro, Katavi, Pwani, Tanga and Dar es Salaam) in Tanzania Mainland, where a total of 3 738 cases and 67 deaths (CFR 1.8%) were reported. Out of 20 regions, a Cholera outbreak was declared over in 12 regions (Manyara, Kigoma, Arusha, Kilimanjaro, Morogoro, Dodoma, Geita, Mwanza, Katavi, Rukwa, Dar es Salaam and Tabora). Currently, the outbreak is active in eight regions with a cumulative total of 1 265 cases and 23 deaths (CFR 1.8%) as of 28 May 2024. (WHO, 16 Jun 2024)

From 1 January to 5 August 2024, a total of 3 920 cases and 66 deaths (CFR 1.7%) were reported from 21 regions, namely, Mara, Kigoma, Kagera, Singida, Simiyu, Shinyanga, Tabora, Ruvuma, Mwanza, Geita, Rukwa, Dodoma, Manyara, Morogoro, Katavi, Pwani, Mtwara, Tanga, Lindi, Dar es Salaam and Songwe.
Simiyu region has contributed the highest number of cases, 843 (21.0%), followed by Mwanza, 788 (11.0%) cases, collectively accounting for 42.0% of all cases. Similarly, the majority of deaths (38 deaths; 58%) were recorded in Simiyu (17), Kagera (8), Kigoma (7) and Shinyanga (6).
As of 5 August 2024, the outbreak had been declared over in more than half (12) of the affected regions, including Mtwara, Katavi, Pwani, Geita, Dodoma, Kagera, Ruvuma, Tanga, Rukwa, Shinyanga, Singida and Dar es Salaam.
Songwe region which had not reported cases since the beginning of the outbreak, has started reporting cases in recent weeks (51 cases with no deaths as of 5 August). (WHO, 8 Sep 2024)