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We are volunteer scientists and healthcare professionals from around the world, working to end this pandemic by contributing our time to address concerns and public health misinformation.

Our #TeamHalo videos bring you accurate, up-to-date facts on the safety & effectiveness of the Covid-19 vaccines and other public health issues.

In response to the COVID-19 pandemic, Team Halo was established as part of the United Nations Verified initiative in partnership with Purpose and the Vaccine Confidence Project at the University of London’s School of Hygiene and Tropical Medicine. Support is provided by Luminate, IKEA Foundation, Rockefeller Foundation and Capgemini.

Featured Guides

These are the many faces, diverse voices, and brilliant minds behind Team Halo.


Dr Natalia Pasternak

Natalia Pasternak is a microbiologist, with a PhD and post-doctorate in Microbiology, in the field of Bacterial Genetics at the University of São Paulo, Brazil. She is the former director in Brazil of the international festival of scientific communication “Pint of Science” (UK), columnist for the Brazilian national newspaper “O Globo”, for The Skeptic magazine (UK), and Medscape (WebMD). She also hosts two weekly radio shows “The hour of Science” at Brazil’s CBN national radio station. She contributes as a visiting professor at the Public Administration School at Fundação Getúlio Vargas, São Paulo, and as a research collaborator at the University of São Paulo.

She is currently the publisher of Question of Science magazine and president of Question of Science Institute, the first Brazilian Institute for the promotion of skepticism and rational thinking. She is the first Brazilian to become a fellow of the Committee for Skeptical Inquiry (CSI) – USA, in recognition of outstanding work in the promotion of science, skepticism and critical thinking. In 2020, and again in 2021, she was chosen Brazilian of the year in Science by IstoE Magazine. She was chosen Personality of the year by the Group of Latin America Daily Newspapers, and received the Ockham Award from The Skeptic magazine, for the promotion of skepticism and rational thinking in Brazil. She has written two books on popularization of science, Science in our daily lives, which won Brazil’s National Literature prize for best science book in 2021 (Prêmio Jabuti), and Against Reality: science denialism, its causes and consequences. She was the only Brazilian listed by BBC as the 100 most influential women of 2021, and she is currently an Adjunct Senior Research Scholar at Columbia University, at the Center for Science and Society, by invitation of Professor Stuart Firestein. Her research focuses on how to improve science communication and combat denialism and misinformation, bringing scientific thinking for future policy makers, and helping to create an international collaboration for science-based global policies.


Dr Nighat Arif

Dr Nighat Arif is a NHS General Practitioner (GP) who has been working on the Covid-19 frontline caring for patients and has contracted Covid-19 herself. Now Dr Nighat’s surgery is administering Covid-19 vaccines. 

Dr Nighat is a family GP specialising in women’s health and family planning.  She is based in Buckinghamshire and is able to consult fluently with patients in Urdu and Punjabi. Nighat is also the resident doctor on BBC Breakfast, ITV’S This Morning and BBC LookEast, updating viewers on the latest medical news. Additionally, Nighat is an ambassador of many charitable causes including Roald Dahl’s Marvellous Children’s Charity, HerSpirit and is heavily involved with supporting NHS Blood and Transplant. 

Dr Nighat remains authentic to her values as a British Pakistani, Muslim woman and mother navigating and uniting the different cultures in a positive way.  She has integrity, substance, humanity and style and approaches life with humour. Nighat is married with three young boys, she loves baking, spin classes with friends, watching movies and reading.


Dr Samir Gupta

Dr Samir Gupta is a Respirologist, Clinician-Scientist and Associate Professor at the University of Toronto. He completed his medical training at McGill University before specializing in Respirology at the University of Toronto. He has a Master’s degree in Clinical Epidemiology and a fellowship in Knowledge Translation Research.

Samir has always had a specific interest in science communication. His academic research further strengthened his resolve that making science accessible and interesting is an urgent need in today’s online world. Samir started his television career at Global with the segment called “On Call With Dr. Gupta,” and is now a medical correspondent across properties on the Canadian Broadcaster, CBC. He appears on multiple networks and communicates about health and science across electronic, print, radio, and television media. As a leading media voice in the COVID-19 pandemic, Samir’s online “explainers” have been viewed over 10 million times. His latest channel is “The Feed With Dr. G.” This work has mostly focused on vaccine safety and the benefits of vaccination, and his research includes work on the behavioral determinants of vaccine hesitancy.

Samir was born and raised in Canada, and like most Canadians, he makes the best out of winter by doing things like sledding and skiing, but his first love has always been dance! As an Indo-Canadian he retains deep ties to India and runs a global health mission in the south of India. He is fluent in English, French, and Hindi, and a big fan of Bollywood!


Dr Kiran Morjaria

Dr Kiran Morjaria is a junior doctor and comedian based in Manchester. He is working on the front line admitting and treating patients with Covid-19. In his spare time he volunteers at a Covid-19 vaccination hub as a vaccinator.

Kiran graduated from Leeds Medical School in 2017, where he was awarded the SPARK scholarship for enterprise, and is currently training to be a GP. He has performed comedy across the national circuit and continues to make medicine accessible and fun online.

Kiran’s big passion outside of medicine is comedy. He also enjoys staying active, he is a keen gym-goer, tennis player and vegetarian foodie.



Follow #TeamHalo Guides for science-backed, shareable videos about COVID-19 vaccines.


Karnyart K Samnuan


Elisa Ramos Sevillano


Prof. Akiko Iwasaki


Dr. Krutika Kuppalli


Jason Kindrachuk


Dr. Angela Rasmussen


Interested in learning more?

If you’re a scientist, healthcare professional, or potential partner who would like to get involved, please get in touch.

Email halo@purpose.com