The COVID-19 pandemic led countries to implement strict public health measures, including systematic screening of international travelers and vaccination, to curb the spread of SARS-CoV-2. Several vaccines have been developed since the onset of the pandemic: inactivated whole-virus vaccines (Sinopharm), recombinant adenovirus vector vaccines encoding the spike protein (AstraZeneca, Johnson & Johnson, Sputnik-V), and mRNA vaccines (Pfizer and Moderna). This study aimed to determine the prevalence of SARS-CoV-2 infection among travelers tested at the University Hospital Center of FANN (CHNU de FANN) and to assess their vaccination status. It was a retrospective study conducted over an 11-month period, from October 2020 to August 2021. All travelers tested at CHNU de FANN were included. Nasopharyngeal samples were analyzed by RT-PCR using the Hummingbird device and Sansure Biotech reagents. Data were extracted from laboratory registers and patient forms, then analyzed with Epi Info software version 3.5.4. Out of 1,164 tests performed, 79 were positive (6.8%). Among the positive cases, 8 patients were under 14 years of age and 8 were over 60. A male predominance was observed (sex ratio = 1.6). Regarding vaccination, 236 travelers were fully vaccinated: Sinopharm (42), Pfizer (44), Johnson & Johnson (35), Moderna (22), AstraZeneca (46), and Sputnik-V (3). However, it should be noted that only patients vaccinated with Sinopharm, Pfizer, Moderna, and Johnson & Johnson developed breakthrough infections. Among the positive cases, 8 had received the Sinopharm vaccine, 4 the Pfizer, 3 the Moderna, and 1 the Johnson & Johnson. These findings highlight the importance of pre-travel screening to limit viral transmission. Further analysis of SARS-CoV-2 variants would be beneficial for enhanced surveillance of viral circulation.
References
[1]
Gandhi, M., Yokoe, D.S. and Havlir, D.V. (2020) Asymptomatic Transmission, the Achilles’ Heel of Current Strategies to Control COVID-19. NewEnglandJournalofMedicine, 382, 2158-2160. https://doi.org/10.1056/nejme2009758
[2]
World Health Organization (2021) COVID-19 Vaccine: BBIBP-CorV (Sinopharm)—Vaccine Details.
[3]
World Health Organization (2021) COVID-19 Vaccine: AZD1222 Vaxzevria (AstraZeneca)—Vaccine Overview.
[4]
World Health Organization (2021) COVID-19 Vaccine: Janssen Ad26.COV2.S-Vaccine Details.
[5]
World Health Organization (2021) COVID-19 Vaccine: Moderna mRNA-1273 (Spikevax)—Vaccine Details.
[6]
World Health Organization (2021) COVID-19 Vaccine: BNT162b2 (Pfizer-BioNTech)—Vaccine Details.
[7]
Asante, L.A., Lwanga, C.N., Takyi, C., Sekyi-Yorke, A.N., Quarcoo, J.A. and Odikro, M.A. (2022) Detection of SARS-CoV-2 Variants Imported Through Land Borders at the Height of the COVID-19 Pandemic in Ghana. Cureus, 14, e68220.
[8]
Akowuah, K.A., Akuffo, R.A., Boateng, A.T., Asigbee, T.W., Bonney, J.H.K., Lamptey, H., et al. (2022) SARS-CoV-2 Infections among Asymptomatic Individuals Contributed to COVID-19 Cases: A Cross-Sectional Study among Prospective Air Travelers from Ghana. FrontiersinPublicHealth, 10, Article 1035763. https://doi.org/10.3389/fpubh.2022.1035763
[9]
Katchunga, P.B., Murhula, A., Akilimali, P., Zaluka, J.C., Karhikalembu, R., Makombo, M., et al. (2021) Seroprevalence of Anti-SARS-CoV-2 Antibodies among Travelers and Workers Screened at Saint Luc Clinic of Bukavu, in the East of the Democratic Republic of Congo, from May to August 2020. PanAfricanMedicalJournal, 38, 93.
[10]
World Health Organization (2021) Antigen-Detection in the Diagnosis of SARS-CoV-2 Infection: Interim Guidance. World Health Organization.
[11]
Ahmed, S.B. and Dumanski, S.M. (2020) Sex, Gender and COVID-19: A Call to Action. Canadian Journal of Public Health, 111, 980-983. https://doi.org/10.17269/s41997-020-00417-z
[12]
Coutures, A. (2020) COVID-19: Chinese Sinopharm Vaccine Less Effective than Pfizer and Moderna. Le HuffPost. https://www.huffingtonpost.fr/science/article/COVID-19-le-vaccin-du-chinois-sinopharm-moins-efficace-que-pfizer-et-moderna_174866.html
[13]
Canada Communicable Disease Report (2021) Impact of COVID-19 Vaccination Status amongst International Travellers. PublicHealthAgencyofCanada, 47, 473-475.
[14]
Feng, A., Obolski, U., Stone, L. and He, D. (2022) Modelling COVID-19 Vaccine Breakthrough Infections in Highly Vaccinated Israel—The Effects of Waning Immunity and Third Vaccination Dose. PLOS Global Public Health, 2, e0001211. https://doi.org/10.1371/journal.pgph.0001211
[15]
Ssentongo, P., Ssentongo, A.E., Voleti, N., Groff, D., Sun, A., Ba, D.M., et al. (2022) SARS-CoV-2 Vaccine Effectiveness against Infection, Symptomatic and Severe COVID-19: A Systematic Review and Meta-Analysis. BMC Infectious Diseases, 22, Article No. 439. https://doi.org/10.1186/s12879-022-07418-y
[16]
Thompson, M.G., Burgess, J.L., Naleway, A.L., Tyner, H., Yoon, S.K., Meece, J., et al. (2021) Prevention and Attenuation of COVID-19 with the BNT162b2 and mRNA-1273 Vaccines. New England Journal of Medicine, 385, 320-329. https://doi.org/10.1056/nejmoa2107058
[17]
Andrews, N., Stowe, J., Kirsebom, F., Toffa, S., Sachdeva, R., Gower, C., et al. (2022) Effectiveness of COVID-19 Booster Vaccines against COVID-19-Related Symptoms, Hospitalization and Death in England. Nature Medicine, 28, 831-837. https://doi.org/10.1038/s41591-022-01699-1
[18]
Hall, V.J., Foulkes, S., Saei, A., Andrews, N., Oguti, B., Charlett, A., et al. (2021) COVID-19 Vaccine Coverage in Health-Care Workers in England and Effectiveness of BNT162b2 mRNA Vaccine against Infection (SIREN): A Prospective, Multi-Centre, Cohort Study. The Lancet, 397, 1725-1735. https://doi.org/10.1016/s0140-6736(21)00790-x
[19]
Haas, E.J., Angulo, F.J., McLaughlin, J.M., Anis, E., Singer, S.R., Khan, F., et al. (2021) Impact and Effectiveness of mRNA BNT162b2 Vaccine against SARS-CoV-2 Infections and COVID-19 Cases, Hospitalisations, and Deaths Following a Nationwide Vaccination Campaign in Israel: An Observational Study Using National Surveillance Data. The Lancet, 397, 1819-1829. https://doi.org/10.1016/s0140-6736(21)00947-8
[20]
Polack, F.P., Thomas, S.J., Kitchin, N., Absalon, J., Gurtman, A., Lockhart, S., et al. (2020) Safety and Efficacy of the BNT162b2 mRNA COVID-19 Vaccine. New England Journal of Medicine, 383, 2603-2615. https://doi.org/10.1056/nejmoa2034577
[21]
Brooks, J.T. and Butler, J.C. (2021) Effectiveness of Mask Wearing to Control Community Spread of SARS-CoV-2. Journal of the American Medical Association, 325, 998-999. https://doi.org/10.1001/jama.2021.1505
[22]
World Health Organization (2022) Policy Brief: Reaching COVID-19 Vaccination Targets.
