On 23 July 2020, the France IHR National Focal Point reported a confirmed autochthonous (locally acquired) case of yellow fever in a 14-year-old male in French Guiana. On 17 July 2020, the case was laboratory confirmed at the French National Reference Centre for arboviruses, Institute Pasteur Cayenne.
The case-patient had severe disability, and developed dengue-like symptoms on 12 July. On 16 July, he was hospitalized in an intensive care unit in Cayenne, French Guiana, with consciousness disorders and acute liver failure, and died on 19 July.
The case-patient’s vaccination history at Mother and Child Welfare Center showed evidence of vaccination for yellow fever at the age of 18 months, however, this was not confirmed by his immunization booklet. In addition, there was no evidence of recommended booster dose as recommended in French Guiana for children between 6 and 10 years of age who were vaccinated before 2 years of age. An initial serology carried out by the Institute Pasteur Cayenne showed absence of detectable antibodies.
The case-patient lived in the village of Cayodé, commune of Maripasoula in French Guiana, with no history of travel outside of the Village. The village of Cayodé is located in the heart of the Amazonian forest, on the riverside, 1-2 hours by pirogue from the town of Maripasoula. According to preliminary results of the epidemiological investigation, the probable place of infection is Maripasoula, Haut-Maroni in French Guiana
A reverse transcription-polymerase chain reaction (RT-PCR) test was conducted at French National Reference Centre for arboviruses, Institute Pasteur Cayenne and was positive for both yellow fever and COVID-19.
Vaccination coverage in the Amerindian country of Upper Maroni is estimated to be between 95 and 100% (estimated at 97.9% in the commune of Maripasoula).1
The epidemiological investigations are nearly complete including an evaluation of the vaccination status of the inhabitants of Cayodé and Haut Maroni, in order to find people who are either not vaccinated or have doubts about their vaccination status.
Aedes aegypti , an urban vector for yellow fever virus, is largely present in French Guiana.
This is the third confirmed case of yellow fever diagnosed since 2017, and the first documented case of co-infection with COVID 19 and yellow fever in French Guiana.
Public health response
- Vector control measures around the risk zone (accommodation and health care facilities);
- Entomological survey is ongoing and anti-vectorial control interventions were launched by the Territorial Collectivity of French Guiana;
- Promote the vaccination of susceptible people, especially in the Amazonia area, migrants and other vulnerable populations. Information dissemination to health care workers to raise awareness about yellow fever and COVID-19;
- Publication of a press release for local awareness on 22 July 2020.
WHO risk assessment
Yellow fever is an acute viral hemorrhagic disease that has the potential to spread rapidly and cause serious public health impact in unimmunized population. Vaccination is the most important means of preventing the infection.
French Guiana is considered at risk for yellow fever transmission. Vaccination coverage in French Guiana is very high and expected to be protective against large-scale yellow fever outbreaks; however, the coverage in some specific populations (especially from the Amazonian area) could be suboptimal and therefore at risk for yellow fever infections.
As several countries and territories in the yellow fever endemic areas are also experiencing an intense transmission of SARS-CoV-2, further cases with co-infection may occur. Similarly, the co-circulation of yellow fever virus and SARS-CoV-2 in areas with higher bed occupancy rates in Intensive Care Units, pose an additional challenge for case management and infection and prevention control activities.
With the global circulation of the virus causing COVID-19, there is a risk of disruption of access to health care due to both COVID-19 related burden on the health system and health care workers. The Pandemic has also led to decreased demand for health care and impacted the routine vaccination activities because of physical distancing requirements. An increase in the number of yellow fever cases or other vaccine preventable diseases (VPD) may result in increased morbidity and mortality predominantly in young infants and other vulnerable groups.
Another aspect in consideration in the light of the current COVID-19 pandemic, is the capacity of the local laboratories and national reference laboratories to process samples due the over demand in processing COVID-19 samples. As of 25 July, French Guiana has reported 7 251 of COVID 19 cases and 41 deaths.
WHO advice
Vaccination coverage should be improved particularly in persons living and working in the forest, who are exposed during the day to sylvatic vectors. It should also be improved in migrants and other vulnerable populations who are more susceptible to being unvaccinated and live in densely populated urban areas (with a risk of urban local transmission), or participate to illegal activities in the forest (with a risk of sporadic cases or clusters in a sylvatic context).
Yellow fever is endemic in French Guiana. This case report illustrates the importance of maintaining awareness of the need for yellow fever vaccination, especially in areas with favorable ecosystem for yellow fever transmission.
WHO recommends vaccination against yellow fever at least 10 days prior to the travel for all international travelers to French Guiana, from nine months of age. French Guiana also requires a yellow fever vaccination certificate for travelers over one year of age.
Yellow fever vaccination is safe, highly effective and provides life-long protection. In accordance with the International Health Regulations (2005), Third edition, the validity of the international certificate of vaccination against yellow fever extends to the life of the person vaccinated. A booster dose of yellow fever vaccine cannot be required of international travelers as a condition of entry.
While countries have different vaccination schedules, the French Guiana Regional Health Agency recommends that children vaccinated before their second birthday require a booster dose between 6 to 10 years of age.
WHO has published guiding principles for immunization activities during the COVID-19 pandemic and is currently developing specific operational guidance for conducting mass vaccination campaigns in the COVID-19 context. When conditions permit, the EYE Strategy will support rapid resumption of preventive yellow fever activities according to WHO guidance .
WHO encourage its Member States to take all actions necessary to keep travelers well informed of risks and preventive measures including vaccination. Travelers should also be made aware of yellow fever symptoms and signs and instructed to rapidly seek medical advice when presenting signs. Travelers returning to French Guiana who may be infected with yellow fever may pose a risk for the establishment of local cycles of yellow fever transmission in areas where the competent vector is present.
WHO does not recommend any restrictions on travel and trade to French Guiana on the basis of the information available.
For more information on yellow fever:
1 Flamand, C., Bailly, S., Fritzell, C., Fernandes Pellerin, S., Toure, A., Chateau, N., Saout, M., Linares, S., Dubois, F., Filleul, L., & Kazanji, M. (2019). Vaccination coverage in the context of the emerging Yellow Fever threat in French Guiana. PLoS neglected tropical diseases, 13(8), e0007661. https://doi.org/10.1371/journal.pntd.0007661
