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. 2023 Feb 9;3(2):e0000906.
doi: 10.1371/journal.pgph.0000906. eCollection 2023.

Etiologies of influenza-like illness and severe acute respiratory infections in Tanzania, 2017-2019

Maria Ezekiely Kelly  1 , Radhika Gharpure  2 , Sabrina Shivji  2 , Miriam Matonya  1 , Solomon Moshi  1 , Ambele Mwafulango  1 , Vumilia Mwalongo  1 , Janneth Mghamba  1 , Azma Simba  1 , S Arunmozhi Balajee  2 , Wangeci Gatei  2   3 , Marcelina Mponela  3 , Grace Saguti  4 , Toni Whistler  2 , Nyambura Moremi  1 , Vida Mmbaga  1
Affiliations

Etiologies of influenza-like illness and severe acute respiratory infections in Tanzania, 2017-2019

Maria Ezekiely Kelly et al. PLOS Glob Public Health. .

Abstract

In 2016, Tanzania expanded sentinel surveillance for influenza-like illness (ILI) and severe acute respiratory infection (SARI) to include testing for non-influenza respiratory viruses (NIRVs) and additional respiratory pathogens at 9 sentinel sites. During 2017-2019, respiratory specimens from 2730 cases underwent expanded testing: 2475 specimens (90.7%) were tested using a U.S. Centers for Disease Control and Prevention (CDC)-developed assay covering 7 NIRVs (respiratory syncytial virus [RSV], rhinovirus, adenovirus, human metapneumovirus, parainfluenza virus 1, 2, and 3) and influenza A and B viruses. Additionally, 255 specimens (9.3%) were tested using the Fast-Track Diagnostics Respiratory Pathogens 33 (FTD-33) kit which covered the mentioned viruses and additional viral, bacterial, and fungal pathogens. Influenza viruses were identified in 7.5% of all specimens; however, use of the CDC assay and FTD-33 kit increased the number of specimens with a pathogen identified to 61.8% and 91.5%, respectively. Among the 9 common viruses between the CDC assay and FTD-33 kit, the most identified pathogens were RSV (22.9%), rhinovirus (21.8%), and adenovirus (14.0%); multi-pathogen co-detections were common. Odds of hospitalization (SARI vs. ILI) varied by sex, age, geographic zone, year of diagnosis, and pathogen identified; hospitalized illnesses were most common among children under the age of 5 years. The greatest number of specimens were submitted for testing during December-April, coinciding with rainy seasons in Tanzania, and several viral pathogens demonstrated seasonal variation (RSV, human metapneumovirus, influenza A and B, and parainfluenza viruses). This study demonstrates that expanding an existing influenza platform to include additional respiratory pathogens can provide valuable insight into the etiology, incidence, severity, and geographic/temporal patterns of respiratory illness. Continued respiratory surveillance in Tanzania, and globally, can provide valuable data, particularly in the context of emerging respiratory pathogens such as SARS-CoV-2, and guide public health interventions to reduce the burden of respiratory illnesses.

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Conflict of interest statement

The authors declare that no competing interests exist.

Figures

Fig 1
Fig 1. Influenza -like illness (ILI) and severe acute respiratory infection (SARI) sentinel surveillance sites in Tanzania, by region and geographic zone.
The map shows the 21 regions (official administrative areas) and 7 geographic zones of mainland Tanzania. The 9 sentinel sites for ILI/SARI surveillance are shown in their respective regions: Kigoma: Kibondo District Hospital (KHD); Mwanza: Mwanza Regional Hospital (MRH); Arusha: Arusha Regional Hospital (ARH) and Meru District Hospital (MDH); Manyara: Haydom Lutheran Hospital (HLH); Dodoma: Dodoma Regional Hospital (DRH); Dar es Salaam: Mwananyamala Municipal Hospital (MMH) and International School of Tanganyika Clinic (IST)*; Mtwara: St. Benedict Referral Hospital (SBH). Map created with MapChart (openly available source): https://www.mapchart.net/. Republished from MapChart under a CC BY license with permission (S1 Text), original copyright 2022. *IST only collected ILI data.
Fig 2
Fig 2. Respiratory virus detection, in total and by ILI/SARI surveillance site—Tanzania, 2017–2019.
Abbreviations: ILI, influenza-like illness; SARI, severe acute respiratory infection; MMH, Mwananyamala Municipal Hospital (Dar es Salaam); KDH, Kibondo District Hospital (Kigoma); ARH, Arusha Regional Hospital (Arusha); SBH, St. Benedict Referral Hospital (Mtwara); MRH, Mwanza Regional Hospital (Mwanza); HLH; Haydom Lutheran Hospital (Manyara); MDH, Meru District Hospital (Arusha); DRH, Dodoma Regional Hospital (Dodoma); IST, International School of Tanganyika Clinic* (Dar es Salaam); n, number of specimens tested; RSV, respiratory syncytial virus; hMPV, human metapneumovirus; PIV, parainfluenza virus (1, 2, and 3). *IST only collected ILI data.
Fig 3
Fig 3. Number of specimens tested for viral respiratory pathogens by month, Tanzania 2017–2019.
Fig 4
Fig 4. Monthly mean percent positivity of viral respiratory pathogens, Tanzania 2017–2019.
Percent positivity by month for respiratory syncytial virus (A), rhinovirus (B), adenovirus (C), human metapneumovirus (hMPV) (D), influenza A and B viruses (E), and parainfluenza viruses (PIV1, PIV2, and PIV3) (F).
See this image and copyright information in PMC

References

    1. Mmbaga VM, Mwasekaga MJ, Mmbuji P, Matonya M, Mwafulango A, Moshi S, et al.. Results from the first 30 months of national sentinel surveillance for influenza in Tanzania, 2008–2010. J Infect Dis. 2012;206 Suppl 1:S80–6. doi: 10.1093/infdis/jis540 - DOI - PubMed
    1. Kishamawe C, Rumisha SF, Mremi IR, Bwana VM, Chiduo MG, Massawe IS, et al.. Trends, patterns and causes of respiratory disease mortality among inpatients in Tanzania, 2006–2015. Trop Med Int Health. 2019;24(1):91–100. doi: 10.1111/tmi.13165 - DOI - PubMed
    1. Radin JM, Katz MA, Tempia S, Talla Nzussouo N, Davis R, Duque J, et al.. Influenza surveillance in 15 countries in Africa, 2006–2010. J Infect Dis. 2012;206 Suppl 1:S14–21. doi: 10.1093/infdis/jis606 - DOI - PubMed
    1. Tadesse M, Mengesha M, Tayachew A, Belay D, Hassen A, Woyessa AB, et al.. Burden and seasonality of medically attended influenza like illness (ILI) in Ethiopia, 2012 to 2017. BMC Infect Dis. 2020;20(1):148. doi: 10.1186/s12879-020-4827-0 - DOI - PMC - PubMed
    1. Yazidi R, Aissi W, Bouguerra H, Nouira M, Kharroubi G, Maazaoui L, et al.. Evaluation of the influenza-like illness surveillance system in Tunisia, 2012–2015. BMC Public Health. 2019;19(1):694. doi: 10.1186/s12889-019-7035-3 - DOI - PMC - PubMed

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