On 3 March 2020, the Ethiopian Public Health Institute (EPHI) reported three suspected yellow fever cases in Enor Ener Woreda, Gurage zone, SNNPR. The three reported cases were members of the same household (father, mother and son) located in a rural kebele. Two of three samples tested positive at national level by reverse transcriptase-polymerase chain reaction (RT-PCR) and were subsequently confirmed positive by plaque reduction neutralization testing (PRNT) at the regional reference laboratory, Uganda Viral Research Institute (UVRI) on 28 March 2020.
In response to the positive RT-PCR results, the EPHI and Ministry of Health performed an in-depth investigation and response, supported by partners including WHO.
As of 6 April 2020, a total of 85 suspected cases have been notified from 6 kebeles in Enor Ener Woreda, of which 54 were reported from Wedesha kebele. Among the total suspected cases, 6 samples tested positive at EPHI national laboratory and they have been referred to UVRI for confirmation.
Public health response
- Epidemiological and entomological investigation has been conducted in Enor Ener Woreda since 8 March 2020.
- Rapid activation of vaccination response has been put in place. The country has rapidly mounted a reactive campaign from 26 to 31 March 2020 targeting approximately 32,000 persons in the affected and surrounding kebeles (12 kebeles total).
- An International Coordination Group (ICG) request is in process by the country for a larger scale reactive campaign.
WHO risk assessment
The risk at national level is assessed as high. The current outbreak in Gurage Zone, SNNP region shows rapid amplification of a yellow fever outbreak in a rural area. In the context of virtually no population immunity, the high number of suspect cases reported over a short time period is of high concern. The recent confirmation of the outbreak in cases with no history of travel is a concern. This is an indication of the existence of conducive factors for an increased incidence of yellow fever transmission and the spread of the disease beyond the hotspot areas.
Recent entomological studies, in addition to previous entomological studies conducted in 2018, have indicated the presence of competent vectors including Aedes species and the potential for spread to surrounding zones. The onset of the rainy season could increase density of mosquito vectors, thereby further exacerbating risk of spread.
Travellers returning to Ethiopia who may be infected with possible high levels of the virus in the blood may pose a risk for the establishment of local cycles of yellow fever transmission in areas where the competent vector is present.
The last yellow fever outbreak occurred in the SNNP region in August 2018, with a total of 35 cases (30 suspected and 5 confirmed cases) reported from the Wolayita Zone in the SNNP region, Ethiopia. While immunization took place in selected aspects of Wolayita Zone, the communities in Gurage zone remain vulnerable to yellow fever infection.
There is currently a low risk at the regional level due to limited population movement both nationally and internationally because of COVID-19 related controls on borders (air/land).
WHO assesses the overall risk to be low at the global level.
WHO advice
Ethiopia is a high priority country for the Eliminate Yellow Fever Epidemic (EYE) strategy. Introduction of yellow fever vaccination into routine immunization is planned for 2020. Vaccination is the primary means for prevention and control of yellow fever. In urban centres, targeted vector control measures are also helpful to interrupt transmission. WHO and partners will continue to support local authorities to implement these interventions to control the current outbreak.
WHO recommends vaccination against yellow fever for all international travellers 9 months of age or older going to Ethiopia. Ethiopia also requires a yellow fever vaccination certificate for travellers aged 9 months or older arriving from countries with risk of yellow fever transmission and for travellers having transited for more than 12 hours through an airport of a country with risk of yellow fever transmission. WHO does not generally recommend vaccination for travellers whose itineraries are limited to Afar and Somali provinces.
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 travellers as a condition of entry.
WHO encourage its Member States to take all actions necessary to keep travellers well informed of risks and preventive measures including vaccination. Travellers should also be made aware of yellow fever symptoms and signs and instructed to rapidly seek medical advice if experiencing signs and symptoms suggestive of yellow fever infection.
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 YF activities according to WHO guidance.
WHO does not recommend any restrictions on travel and trade to Ethiopia on the basis of the information available on this outbreak.
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