TEAM
Yajna Ramphal
CERI Team

Yajna
Ramphal

CLIMADE Project Manager

Yajna is a Research Project Manager with a background in bioinformatics and computational biology, working at the intersection of genomics, epidemiology, and public health. Her work focuses on analysing genomic data to respond to climate-sensitive diseases and outbreak preparedness in Africa. At CERI, she supports the coordination and delivery of interdisciplinary research projects within the Climate Amplified Diseases and Epidemics in Africa (CLIMADE-Africa) consortium. Her research interests include infectious disease genomics, host genetics, and phylodynamics, with a focus on translating complex data into actionable insights for public health decision-making. Outside of work, Yajna explores her creative side and is passionate about personal growth and building an inclusive, impactful scientific community.

Linkedin

// Research Output

Publications

2026
Chikungunya virus

Ramphal Y, de Oliveira T

Nature Ecology & Evolution
10:610-610
2026
Chikungunya virus

Ramphal Y, de Oliveira T

Nature Ecology & Evolution
10:610-610
2025
Identifying genomic surveillance gaps in Africa for the global public health response to West Nile virus: a systematic review

Moir M, Sitharam N, Hofstra L, Dor G, Mwanyika G, Ramphal Y, Reichmuth M, San J, Gifford R, Wilkinson E, Tshiabuila D, Preiser W, Konou A, Bitew M, Onoja A, Paganotti G, Abera A, Maror J, Kayiwa J, Abuelmaali S, Lusamaki E, de Oliveira T, Alcantara L, Holmes E, Padane A, Musa A, Abera A, Campbell A, Ssemaganda A, Ahouidi A, Muianga A, Samson A, Onoja A, Alemu B, Foka C, Baxter C, van Zyl D, de Castro Silva D, Martin D, Wilkinson E, Kouma E, Simo F, Mwanyika G, Godebo G, D’or G, Tegally H, Omara I, Maror J, Poonagavan J, Juma J, Oludele J, Xavier J, Lourenco J, Fokam J, Maeka K, Singh L, Chabuka L, Issaka M, Hofstra M, Giovanetti M, Faye M, Koffi M, Owusu M, Dikongo M, Alimohamed M, Bitew M, Moir M, Kraemer M, Sitharam N, Jerome N, Mbhele N, Miantsatian Andry N, Tomori O, Magalutcheemee R, Guimaraes R, Oyola S, Abuelmaali S, Golubchik T, Fonseca V, Preiser W, Ramphal Y, Venter M, Burt F, Baxter C, Lessells R, de Oliveira T, Tegally H

The Lancet Microbe
6:101176
2025
Tracing the spatial origins and spread of SARS-CoV-2 Omicron lineages in South Africa

Dor G, Wilkinson E, Martin DP, Moir M, Tshiabuila D, Kekana D, Ntozini B, Joseph R, Iranzadeh A, Nyaga MM, Goedhals D, Maponga T, Maritz J, Laguda-Akingba O, Ramphal Y, MacIntyre C, Chabuka L, Pillay S, Giandhari J, Baxter C, Hsiao NY, Preiser W, Bhiman JN, Davies MA, Venter M, Treurnicht FK, Wolter N, Williamson C, von Gottberg A, Lessells R, Tegally H, de Oliveira T

Nature Communications
28;16(1):4937. doi: 10.1038/s41467-025-60081-0
2025
Identifying genomic surveillance gaps in Africa for the global public health response to West Nile Virus

Moir M, Sitharam N, Hofstra M, Dor G, Mwanyika G, Ramphal Y, Reichmuth M, James S, Gifford R, Wilkinson E, Tshiabuila D, Preiser W, Konou A, Bitew M, Onoja B, Paganotti G, Abera A, Maror J, Kayiwa J, Abuelmaali S, Lusamaki E, , Venter M, Burt F, Baxter C, Lessells R, de Oliveira T, Tegally H

doi: 10.1101/2024.12.18.629123.
2024
Dengue virus importation risks in Africa: a modelling study

Poongavanan J, Lourenço J, Tsui J, Colizza V, Ramphal Y, Baxter C, Kraemer M, Dunaiski M, de Oliveira T, Tegally H

The Lancet Planetary Health
8(12):e1043-e1054. doi: 10.1016/s2542-5196(24)00272-9.
2024
Understanding the Transmission Dynamics of the Chikungunya Virus in Africa

Ramphal Y, Tegally H, San JE, Reichmuth ML, Hofstra M, Wilkinson E, Baxter C, Climade Consortium, de Oliveira T, Moir M

Pathogens
13(7):605. doi: 10.3390/pathogens13070605
2024
Disentangling seasonal introduction and establishment risk of dengue in Africa

Poongavanan J, Lourenço J, Tsui JHL, Colizza V, Ramphal Y, Baxter C, Kraemer MOG, Dunaiski M, de Oliveira T, Tegally H

medRxiv [Preprint]
https://doi.org/10.1101/2024.05.07.24306997
2023
An emerging clade of Chikungunya West African genotype discovered in real-time during 2023 outbreak in Senegal

Padane A, Tegally H, Ramphal Y, Ndiaye S, Sarr M, Diop M, Diedhiou CK, Mboup A, Diouf N, Souare A, Diagne ND, Aza-Gnandji M, Dabo NA, Dia YA, Diaw NA, Leye N, Diaw PA, Ambroise A, Cisse B, Diallo AS, Diop O, Diallo AA, Ndoye S, Sanko TJ, Baxter C, Wilkinson E, James SE, Tshiabuila D, Naidoo Y, Pillay S, Lessells R, Cisse K, Leye A, Mbaye A, Kania D, Traore I, Kagone ST, Tinto B, Ouedraogo A, Lourenco J, Giovanetti M, Giandhari J, de Oliveira T, Mboup S

medrxiv
MEDRXIV-2023-298527v1
2023
Molecular Epidemiology of SARS-CoV-2 during Five COVID-19 Waves and the Significance of Low-Frequency Lineages

Subramoney K, Mtileni N, Giandhari J, Naidoo Y, Ramphal Y, Pillay S, Ramphal U, Maharaj A, Tshiabuila D, Tegally H, Wilkinson E, de Oliveira T, Fielding BC, Treurnicht FK

Viruses
15(5):1194. doi: 10.3390/v15051194
2023
SARS-CoV-2 spike protein diversity at an intra-host level, among SARS-CoV-2 infected individuals in South Africa, 2020 to 2022

Subramoney K, Mtileni N, Davis A, Giandhari J, Tegally H, Wilkinson E, Naidoo Y, Ramphal Y, Pillay S, Ramphal U, Simane A, Reddy B, Mashishi B, Mbenenge N, de Oliveira T, Fielding BC, Treurnicht FK

PLoS One
18(5):e0286373. doi: 10.1371/journal.pone.0286373
2023
Genomic epidemiology of SARS-CoV-2 during the first four waves in Mozambique

Ismael N, van Wyk S, Tegally H, Giandhari J, San JE, Moir M, Pillay S, Utpatel C, Singh L, Naidoo Y, Ramphal U, Mabunda N, Abílio N, Arnaldo P, Xavier J, Amoako DG, Everatt J, Ramphal Y, Maharaj A, de Araujo L, Anyaneji UJ, Tshiabuila D, Viegas S, Lessells R, Engelbrecht S, Gudo E, Jani I, Niemann S, Wilkinson E, de Oliveira T

PLOS Glob Public Health
6;3(3):e0001593. doi: 10.1371/journal.pgph.0001593
2023
Molecular Epidemiology and Diversity of SARS-CoV-2 in Ethiopia 2020-2022

Sisay A, Tshiabuila D, van Wyk S, Tesfaye A, Mboowa G, Oyola SO, Tesema SK, Baxter C, Martin D, Lessells R, Tegally H, Moir M, Giandhari J, Pillay S, Singh L, Ramphal Y, Maharaj A, Pillay Y, Maharaj A, Naidoo Y, Ramphal U, Chabuka L, Wilkinson E, de Oliveira T, Desta AF, San JE

Genes
13;14(3):705. doi: 10.3390/genes14030705
2022
The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

Tegally H, San JE, Cotten M, Moir M, Tegomoh B, Mboowa G, Martin DP, Baxter C, Lambisia AW, Diallo A, Amoako DG, Diagne MM, Sisay A, Zekri AN, Gueye AS, Sangare AK, Ouedraogo AS, Sow A, Musa AO, Sesay AK, Abias AG, Elzagheid AI, Lagare A, Kemi AS, Abar AE, Johnson AA, Fowotade A, Oluwapelumi AO, Amuri AA, Juru A, Kandeil A, Mostafa A, Rebai A, Sayed A, Kazeem A, Balde A, Christoffels A, Trotter AJ, Campbell A, Keita AK, Kone A, Bouzid A, Souissi A, Agweyu A, Naguib A, Gutierrez AV, Nkeshimana A, Page AJ, Yadouleton A, Vinze A, Happi AN, Chouikha A, Iranzadeh A, Maharaj A, Batchi-Bouyou AL, Ismail A, Sylverken AA, Goba A, Femi A, Sijuwola AE, Marycelin B, Salako BL, Oderinde BS, Bolajoko B, Diarra B, Herring BL, Tsofa B, Lekana-Douki B, Mvula B, Njanpop-Lafourcade BM, Marondera BT, Khaireh BA, Kouriba B, Adu B, Pool B, McInnis B, Brook C, Williamson C, Nduwimana C, Anscombe C, Pratt CB, Scheepers C, Akoua-Koffi CG, Agoti CN, Mapanguy CM, Loucoubar C, Onwuamah CK, Ihekweazu C, Malaka CN, Peyrefitte C, Grace C, Omoruyi CE, Rafaï CD, Morang'a CM, Erameh C, Lule DB, Bridges DJ, Mukadi-Bamuleka D, Park D, Rasmussen DA, Baker D, Nokes DJ, Ssemwanga D, Tshiabuila D, Amuzu DSY, Goedhals D, Grant DS, Omuoyo DO, Maruapula D, Wanjohi DW, Foster-Nyarko E, Lusamaki EK, Simulundu E, Ong'era EM, Ngabana EN, Abworo EO, Otieno E, Shumba E, Barasa E, Ahmed EB, Ahmed EA, Lokilo E, Mukantwari E, Philomena E, Belarbi E, Simon-Loriere E, Anoh EA, Manuel E, Leendertz F, Taweh FM, Wasfi F, Abdelmoula F, Takawira FT, Derrar F, Ajogbasile FV, Treurnicht F, Onikepe F, Ntoumi F, Muyembe FM, Ragomzingba FEZ, Dratibi FA, Iyanu FA, Mbunsu GK, Thilliez G, Kay GL, Akpede GO, van Zyl GU, Awandare GA, Kpeli GS, Schubert G, Maphalala GP, Ranaivoson HC, Omunakwe HE, Onywera H, Abe H, Karray H, Nansumba H, Triki H, Kadjo HAA, Elgahzaly H, Gumbo H, Mathieu H, Kavunga-Membo H, Smeti I, Olawoye IB, Adetifa IMO, Odia I, Ben Boubaker IB, Mohammad IA, Ssewanyana I, Wurie I, Konstantinus IS, Halatoko JWA, Ayei J, Sonoo J, Makangara JC, Tamfum JM, Heraud JM, Shaffer JG, Giandhari J, Musyoki J, Nkurunziza J, Uwanibe JN, Bhiman JN, Yasuda J, Morais J, Kiconco J, Sandi JD, Huddleston J, Odoom JK, Morobe JM, Gyapong JO, Kayiwa JT, Okolie JC, Xavier JS, Gyamfi J, Wamala JF, Bonney JHK, Nyandwi J, Everatt J, Nakaseegu J, Ngoi JM, Namulondo J, Oguzie JU, Andeko JC, Lutwama JJ, Mogga JJH, O'Grady J, Siddle KJ, Victoir K, Adeyemi KT, Tumedi KA, Carvalho KS, Mohammed KS, Dellagi K, Musonda KG, Duedu KO, Fki-Berrajah L, Singh L, Kepler LM, Biscornet L, de Oliveira Martins L, Chabuka L, Olubayo L, Ojok LD, Deng LL, Ochola-Oyier LI, Tyers L, Mine M, Ramuth M, Mastouri M, ElHefnawi M, Mbanne M, Matsheka MI, Kebabonye M, Diop M, Momoh M, Lima Mendonça MDL, Venter M, Paye MF, Faye M, Nyaga MM, Mareka M, Damaris MM, Mburu MW, Mpina MG, Owusu M, Wiley MR, Tatfeng MY, Ayekaba MO, Abouelhoda M, Beloufa MA, Seadawy MG, Khalifa MK, Matobo MM, Kane M, Salou M, Mbulawa MB, Mwenda M, Allam M, Phan MVT, Abid N, Rujeni N, Abuzaid N, Ismael N, Elguindy N, Top NM, Dia N, Mabunda N, Hsiao NY, Silochi NB, Francisco NM, Saasa N, Bbosa N, Murunga N, Gumede N, Wolter N, Sitharam N, Ndodo N, Ajayi NA, Tordo N, Mbhele N, Razanajatovo NH, Iguosadolo N, Mba N, Kingsley OC, Sylvanus O, Femi O, Adewumi OM, Testimony O, Ogunsanya OA, Fakayode O, Ogah OE, Oludayo OE, Faye O, Smith-Lawrence P, Ondoa P, Combe P, Nabisubi P, Semanda P, Oluniyi PE, Arnaldo P, Quashie PK, Okokhere PO, Bejon P, Dussart P, Bester PA, Mbala PK, Kaleebu P, Abechi P, El-Shesheny R, Joseph R, Aziz RK, Essomba RG, Ayivor-Djanie R, Njouom R, Phillips RO, Gorman R, Kingsley RA, Neto Rodrigues RMDESA, Audu RA, Carr RAA, Gargouri S, Masmoudi S, Bootsma S, Sankhe S, Mohamed SI, Femi S, Mhalla S, Hosch S, Kassim SK, Metha S, Trabelsi S, Agwa SH, Mwangi SW, Doumbia S, Makiala-Mandanda S, Aryeetey S, Ahmed SS, Ahmed SM, Elhamoumi S, Moyo S, Lutucuta S, Gaseitsiwe S, Jalloh S, Andriamandimby SF, Oguntope S, Grayo S, Lekana-Douki S, Prosolek S, Ouangraoua S, van Wyk S, Schaffner SF, Kanyerezi S, Ahuka-Mundeke S, Rudder S, Pillay S, Nabadda S, Behillil S, Budiaki SL, van der Werf S, Mashe T, Mohale T, Le-Viet T, Velavan TP, Schindler T, Maponga TG, Bedford T, Anyaneji UJ, Chinedu U, Ramphal U, George UE, Enouf V, Nene V, Gorova V, Roshdy WH, Karim WA, Ampofo WK, Preiser W, Choga WT, Ahmed YA, Ramphal Y, Bediako Y, Naidoo Y, Butera Y, de Laurent ZR; Africa Pathogen Genomics Initiative (Africa PGI), Ouma AEO, von Gottberg A, Githinji G, Moeti M, Tomori O, Sabeti PC, Sall AA, Oyola SO, Tebeje YK, Tessema SK, de Oliveira T, Happi C, Lessells R, Nkengasong J, Wilkinson E

Science
eabq5358. doi: 10.1126/science.abq5358
2022
Impact of intra-host immune adaptations on the evolution of SARS-CoV-2 S protein among individuals with SARS-CoV-2 infections in South Africa, 2020 to 2022.

Subramoney K, Mtileni N, Davis A, Giandhari J, Naidoo Y, Ramphal Y, Pillay S, Ramphal U, Tegally H, Wilkinson E, Simane A, Reddy B, Mashishi B, Mbenenge N, de Oliveira T, Fielding B, Treurnicht F

Authorea Preprints
DOI: 10.22541/au.166305249.90395426/v1
2022
Identification of SARS-CoV-2 Omicron variant using spike gene target failure and genotyping assays, Gauteng, South Africa, 2021

Subramoney K, Mtileni N, Bharuthram A, Davis A, Kalenga B, Rikhotso M, Maphahlele M, Giandhari J, Naidoo Y, Pillay S, Ramphal U, Ramphal Y, Tegally H, Wilkinson E, Mohale T, Ismail A, Mashishi B, Mbenenge N, de Oliveira T, Makatini Z, Fielding BC, Treurnicht FK

J Med Virol.
4(8):3676-3684. doi: 10.1002/jmv.27797
2022
Omicron infection enhances Delta antibody immunity in vaccinated persons

Khan K, Karim F, Cele S, Reedoy K, San EJ, Lustig G, Tegally H, Rosenberg Y, Bernstein M, Jule Z, Ganga Y, Ngcobo N, Mazibuko M, Mthabela N, Mhlane Z, Mbatha N, Miya Y, Giandhari J, Ramphal Y, Naidoo T, Sivro A, Samsunder N, Kharsany A, Amoako D, Bhiman J, Manickchund N, Karim Q, Magula N, Abdool Karim SS, Gray G, Hanekom W, von Gottberg A, Milo R, Gosnell B, Lessells R, Moore P, de Olveira T, Moosa M-Y S, Sigal A

Nature
https://doi.org/10.1038/s41586-022-04830-x
2022
Rapid Replacement of SARS-CoV-2 Variants by Delta and Subsequent Arrival of Omicron, Uganda, 2021

Bbosa N, Ssemwanga D, Namagembe H, Kiiza R, Kiconco J, Kayiwa J, Lutalo T, Lutwama J, Ssekagiri A, Ssewanyana I, Nabadda S, Kyobe-Bbosa H, Giandhari J, Pillay S, Ramphal U, Ramphal Y, Naidoo Y, Tshiabuila D, Tegally H, San EJ, Wilkinson E, de Oliveira T, Kaleebu P

Emerg Infect Dis
doi: 10.3201/eid2805.220121
2022
Comparison of SARS-CoV-2 sequencing using the ONT GridION and the Illumina MiSeq

Tshiabuila D, Giandhari J, Pillay S, Ramphal U, Ramphal Y, Maharaj A, Anyaneji UJ, Naidoo Y, Tegally H, San EJ, Wilkinson E, Lessells R, de Oliveira T

Research Square
https://doi.org/10.21203/rs.3.rs-1249711/v1
2022
Omicron infection of vaccinated individuals enhances neutralizing immunity against the Delta variant.

Khan K, Karim F, Cele S, San JE, Lustig G, Tegally H, Rosenberg Y, Bernstein M, Ganga Y, Jule Z, Reedoy K, Ngcobo N, Miya Y, Mazibuko M, Mthabela N, Mhlane Z, Mbatha N, Giandhari J, Ramphal Y, Naidoo T, Manickchund N, Magula N, Karim SA, Gray G, Hanekom W, von Gottberg A, Milo R, Gosnell B, Lessells R, de Oliveira T, Moore P, Moosa YS, Sigal A.

medRxiv
2021.12.27.21268439. doi: 10.1101/2021.12.27.21268439
2022
Rapid epidemic expansion of the SARS-CoV-2 Omicron variant in southern Africa

Viana R, Moyo S, Amoako DG, Tegally H, Scheepers C, Althaus CL, Anyaneji UJ, Bester PA, Boni MF, Chand M, Choga WT, Colquhoun R, Davids M, Deforche K, Doolabh D, du Plessis L, Engelbrecht S, Everatt J, Giandhari J, Giovanetti M, Hardie D, Hill V, Hsiao NY, Iranzadeh A, Ismail A, Joseph C, Joseph R, Koopile L, Kosakovsky Pond SL, Kraemer MUG, Kuate-Lere L, Laguda-Akingba O, Lesetedi-Mafoko O, Lessells RJ, Lockman S, Lucaci AG, Maharaj A, Mahlangu B, Maponga T, Mahlakwane K, Makatini Z, Marais G, Maruapula D, Masupu K, Matshaba M, Mayaphi S, Mbhele N, Mbulawa MB, Mendes A, Mlisana K, Mnguni A, Mohale T, Moir M, Moruisi K, Mosepele M, Motsatsi G, Motswaledi MS, Mphoyakgosi T, Msomi N, Mwangi PN, Naidoo Y, Ntuli N, Nyaga M, Olubayo L, Pillay S, Radibe B, Ramphal Y, Ramphal U, San JE, Scott L, Shapiro R, Singh L, Smith-Lawrence P, Stevens W, Strydom A, Subramoney K, Tebeila N, Tshiabuila D, Tsui J, van Wyk S, Weaver S, Wibmer CK, Wilkinson E, Wolter N, Zarebski AE, Zuze B, Goedhals D, Preiser W, Treurnicht F, Venter M, Williamson C, Pybus OG, Bhiman J, Glass A, Martin DP, Rambaut A, Gaseitsiwe S, von Gottberg A, de Oliveira T

Nature
doi: 10.1038/s41586-022-04411-y
2021
Rapid replacement of the Beta variant by the Delta variant in South Africa

Tegally H, Wilkinson E, Althaus C, Giovanetti M, San J, Giandhari J, Pillay S, Naidoo Y, Ramphal U, Msomi N, Mlisana K, Amoako D, Everatt J, Mohale T, Nguni A, Mahlangu B, Ntuli N, Khumalo Z, Makatini Z, Wolter N, Scheepers C, Ismail A, Doolabh D, Joseph R, Strydom A, Mendes A, Davids M, Mayaphi S, Ramphal Y, Maharaj A, Karim W, Tshiabuila D, Anyaneji U, Singh L, Engelbrecht S, Fonseca V, Marais K, Korsman S, Hardie D, Hsiao N, Maponga T, van Zyl G, Marais G, Iranzadeh A, Martin D, Alcantara L, Bester P, Nyaga M, Subramoney K, Treurnicht F, Venter M, Goedhals D, Preiser W, Bhiman J, vonGottberg A, Williamson C, Lessells R, de Oliveira T

medRxiv
MEDRXIV-2021-264018v1